Glutathione and inflammation -
Interestingly, among the genes upregulated by LPS and decreased by BSO Group 2 , we found genes important in innate immunity and inflammation il1b, Irf7, Irf9, Mx2, Oas2, Oas3, Ptgs2 , as well as the secreted l -phenylalanine oxidase, il4i1. None of these genes were affected by BSO alone. The list of the top 15 transcripts most affected by BSO among those downregulated by LPS is available as Table S1 in Supplementary Material.
The general functions of the four groups of genes differentially regulated by GSH depletion and LPS were then analyzed using DAVID to identify the enriched GO:BP categories and KEGG pathways For this purpose, we combined the list of differentially expressed genes at 2 and 6 h. Figure 4 shows the KEGG and GO:BP categories overrepresented in each of the four groups.
Only categories that included three or more genes are shown. The analysis confirms that Group 1 included genes associated with the response to oxidative stress. Group 2 included genes associated with immune response, inflammation, and antiviral host defense such as interferon IFN and toll-like receptor TLR signaling.
Figure 4. Enriched functional categories in the four groups of genes differentially regulated by LPS and BSO. The lists of genes in the four groups at 2 and 6 h were combined and the overrepresented GO biological process GO:BP categories white bars and KEGG pathways gray bars were obtained by DAVID analysis.
All categories identified by DAVID for Groups 1—4 are reported. BSO, buthionine sulfoximine; GO:BP, gene ontology biological process; LPS, lipopolysaccharide. Among the genes whose expression was inhibited by LPS Groups 3 and 4 , only few mapped to some functional category.
Group 3 included genes associated with xenobiotics metabolism such as GSH transferases mu 1—4 and cytochrome P The only genes that were part of a functional category in Group 4 were C1q components. To identify possible common molecular mechanisms responsible for the differential regulation by BSO of the LPS-induced genes in Groups 1 and 2, we performed an unbiased analysis for the overrepresented TF-binding sites using oPOSSUM software In Group 1 Figure 5 A , the TF results in the highest Fisher score and a high number of target genes was NFE2L2 nrf2 , whose main function is the response to oxidative stress, thus confirming the results obtained with DAVID.
In Group 2 Figure 5 B , the TF that had the highest score was NF-kB with its various subunits. Figure 5. The number in parentheses indicates the number of transcripts that map to each TF. TF, transcription factor. We thus manually searched our dataset for the expression of known NF-kB target genes.
However, only 8 out of 87 at 2 h and 4 out of at 6 h were downregulated by BSO. Thus, because only a very small percentage of NF-kB target genes induced by LPS are in Group 2 downregulated by BSO , we could rule out that BSO acts simply by downregulating NF-kB.
Microarray results were validated by RT-qPCR for 11 genes Figures 6 and 7. Ten genes were selected from Groups 1 or 2, at 2 and 6 h. Since we have a specific interest in this gene, it was selected for validation by RT-qPCR.
Figure 6. PCR validation of the microarray data at 2 h. Data are expressed as fold change vs one of the respective control samples.
For each experimental group, the mean is also shown. PCR, polymerase chain reaction. Figure 7. PCR validation of the microarray data at 6 h. We performed validation in two sets of samples: one with the same RNA used for the microarray experiment qPCR1 and one with RNA from an entirely independent experiment qPCR2.
For all 11 genes tested, PCR confirmed the differential expression detected by microarray analysis both at 2 and 6 h Figures 6 and 7 , respectively. In the second experiment, at 2 h results were confirmed for five out of seven genes, including il1b, Irf9, Mx2, Il4i1, and Srxn1; at 6 h, three genes out of four were validated including Prdx1, Nos2, and Slc7a Interestingly, by RT-qPCR we could find a statistically significant inhibitory effect of BSO on LPS-induced Nos2, which did not pass the correction for multiple comparisons; this is not surprising, since the false discovery rate correction, being more conservative, can generate false negatives.
We decided to show the more reliable results obtained in the two independent experiments assayed by PCR Figure 7 ; however, for consistency, Nos2 was not included in any subsequent analysis functional analysis, TF analysis , and is not listed in File S1 in Supplementary Material.
We wondered whether the GSH requirement in the induction of genes in the IFN response pathway in Group 2 was biologically relevant. Therefore, we investigated the effect of LPS on PR8 influenza virus infection in RAW cells in which GSH had been depleted by BSO.
As shown in Figure 8 , when cells were infected with PR8, LPS reduced infection, in terms of intracellular viral protein production; influenza nucleoprotein NP, the most expressed among the viral proteins was significantly decreased in cells pretreated with LPS.
However, the effect of LPS was not observed in GSH-depleted cells. Although, as reported previously, BSO alone increased NP production 21 , the treatment with both LPS and BSO induced a further significant increase.
Figure 8. LPS activation of antiviral innate immunity is dependent on GSH. A Western blot for influenza virus proteins in RAW cells infected with PR8 or uninfected, after LPS treatment, with and without GSH depletion. β-Actin was used as loading control. B Levels of NP viral protein in RAW cells pretreated with LPS, with and without GSH depletion.
GSH, glutathione; LPS, lipopolysaccharide; NP, nucleoprotein. We next asked the question whether the inhibitory effect of GSH on Group 1 genes, as revealed by the upregulation by BSO, might be due to its ROS-scavenging antioxidant action. To answer this, we first investigated whether the induction of Group 1 genes by LPS was inhibitable by the thiol antioxidant NAC.
Second, to investigate whether ROS generation induced by LPS could have a role in the induction of Group 1 genes, we asked whether a ROS-generating agent menadione would reproduce the effect of LPS.
As shown in Figure 9 , NAC did not alter the induction of selected Group 1 genes Srx1, Prdx1, Slc7a On the other hand, all these genes were induced by menadione alone. Figure 9. Effect of NAC and menadione on Group 1 left and Group 2 right genes. Menadione Men was added at 10 µM for 2 h.
Gene expression was measured by qPCR. Data are expressed as fold change vs one of the control samples, and are the mean ± SD of six biological replicates from two independent experiments. LPS, lipopolysaccharide; NAC, N -acetyl- l -cysteine; qPCR, quantitative polymerase chain reaction.
The same experimental framework was used to study the relevance of the ROS scavenging properties of GSH in its permissive role for the induction of Group 2 genes.
Opposite to what observed with Group 1 genes, menadione by itself was unable to regulate the expression of any of Group 2 genes measured.
This study supports the view that endogenous GSH plays a pivotal role for the establishment of the innate immune responses to viruses, possibly acting as a signaling molecule with a mechanism different from simple scavenging of ROS. The fact that the vast majority of transcripts were unaffected by BSO is also an indirect confirmation that, within the concentrations and incubation times used, BSO does not have significant toxic or non-specific effects.
The observation that GSH depletion does not exacerbate the transcription of inflammatory genes, at least in our experimental conditions, might seem at variance with the existing literature starting from pioneering paper by Schreck et al.
However, most of that evidence is based on in vitro or in vivo experiments using exogenously administered thiol antioxidants or pro-oxidants. What our data do not support is the extrapolation of evidence from those experiments to the conclusion that GSH is an endogenous anti-inflammatory molecule through its ROS-scavenging activity.
In fact, previous reports noted that exogenous GSH or its precursor NAC inhibits the production and expression of TNF, IL-6, and IL-8 by LPS-stimulated macrophages in the absence of any significant change in intracellular GSH The results reported here are also in agreement with our previous studies where we observed that there are more H 2 O 2 -induced genes that require GSH for their upregulation than genes whose induction by H 2 O2 is exacerbated by GSH depletion Interestingly, in that study using human monocytic cells, many of the H 2 O 2 -induced genes for which GSH had a facilitatory role were related to immunity In addition, the only LPS-induced transcripts mapping to innate immunity in their functional annotation were inhibited, rather than upregulated, by GSH depletion Group 2 genes.
Not only innate immunity genes in Group 2 require GSH for their induction but also they were not induced by ROS alone using menadione as a ROS-generating chemical and their LPS induction was not inhibited by NAC, ruling out the possibility that ROS act as signaling molecules in their induction by LPS.
The only exception was il1b whose LPS induction was inhibited by NAC but was also inhibited by GSH depletion, suggesting that GSH is important for IL-1b induction by LPS but possibly not through an antioxidant mechanism because i exogenous NAC and endogenous GSH appear to have an opposite role, and ii an oxidant alone does not induce IL-1b expression.
In line with these findings, it has been shown that molecules altering intracellular thiol content with different mechanisms i. The innate immune response is also important for antiviral defense and activation of TLR4 leads to induction of antiviral proteins including IFNs and IFN-related genes 27 , 28 such as MxA and Oas 29 , Our data, although obtained in a model where infectivity was low, suggest that GSH is important for the activation of an antiviral response.
This happens without affecting inflammatory genes, except for IL-1b whose induction was also facilitated by the presence of GSH. There is evidence for a fine-tuning of TLR signaling 31 , and these data indicate that GSH may be important in directing it toward specific small patterns of genes implicated in host defense rather than toward those responsible for the inflammatory response, as outlined in Figure Figure GSH fine-tuning of TLR4 signaling.
GSH orients the TLR4-mediated changes in gene expression profile toward activation of host defense. GSH, glutathione; LPS, lipopolysaccharide; TLR4, toll-like receptor 4. The behavior of genes in Group 1 is what one would expect.
They include enzymes for GSH synthesis and antioxidant enzymes such as Prdx1, Srxn1, and Hmox. All these genes map to nrf2, a master regulator of redox homeostasis Their regulation by BSO is in accordance with the hypothesis that endogenous GSH acts as an ROS scavenger because menadione induces their expression.
However, NAC did not inhibit their induction by LPS, suggesting that LPS induces nrf2 target gene expression independently of the increase in ROS production. This agrees with a recent study by Cuadrado et al.
showing that LPS can activate nrf2 via the small GTPase RAC1, independently of ROS In this picture, endogenous GSH might be important through other mechanisms than just scavenging ROS. In fact, nrf2 activation is dependent on oxidation of its redox sensor, keap1.
Several studies have indicated that activation of nrf2 by administration of electrophilic compounds has an anti-inflammatory effect and decreases LPS-induced transcription of other NF-kB target genes, including TNF, IL-1b, and IL-6, in RAW cells 35 , However, as mentioned earlier, in our experimental conditions in which nrf2 was likely activated by GSH depletion, as suggested by the increased expression of nrf2 target genes, we have not observed an effect on any inflammatory cytokine other than IL-1b.
Once again, the difference might be that we did not use exogenous electrophiles to induce nrf2. This highlights one point that is often overlooked. GSH is not just an antioxidant that participates in ROS elimination either via its direct ROS scavenging activity or as a substrate for GSH peroxidases but, like any other thiol including NAC, is also a reducing agent, as well as GSSG is a thiol oxidizing agent.
Therefore, these two molecular species, GSH and GSSG, can regulate biological pathways in a redox-dependent manner, independently of ROS scavenging.
In fact, protein glutathionylation is a major mechanism of redox regulation of immunity 10 , 37 , affecting the function of key proteins including NF-kB 38 , STAT3 39 , PKA 40 , TRAF3, and TRAF6 41 , as well as participating in the release of danger signals 42 , However, in this experimental model, the induction of host defense genes in Group 2 at least those shown in Figure 7 , il1b, Mx2, and Irf9 is inhibited by BSO, evidencing the need for GSH, but is not amplified by NAC, suggesting that scavenging LPS-induced ROS is not the main mechanism of action of endogenous GSH.
The finding that several genes that are important for the antiviral response, mostly part of IFN signaling pathways, including the antiviral proteins Oas and Mx2, require GSH for optimal induction by LPS adds knowledge to previous findings, indicating that GSH can inhibit viral infection 44 , 45 and that viral infection causes release of glutathionylated thioredoxin and Prdx There is a large body of evidence showing the importance of GSH in immunity, including antiviral immunity 47 , but so far this was ascribed to its action as ROS scavenger to inhibit oxidative stress.
The present study indicates that GSH has other important signaling roles independently of protection from oxidative stress, and its action may not be vicariated by another thiol antioxidant. However, to understand the validity of our conclusions to other models, one needs to bear in mind the limitations of this study that is investigating mRNAs in a cell line.
Future studies will need to measure the proteins of interest for instance, IL-1b to see whether the changes observed at the level of transcripts are reflected in changes in protein levels.
To generalize the relevance of this mechanism, the observation will need to be confirmed in primary cells, including human cells, and possibly in vivo. MD, PC, MM, IC, LC, FP, and KA performed experiments.
AH, PG, KA, LC, MM, FP, and AP designed and supervised experiments. MD, PG, MM, FP, and PC wrote the paper. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
This work was supported by a fellowship program from Istituto Pasteur Italia——Fondazione Cenci Bolognetti to PC , PRIN CUP grant number B to AP , and RM Phillips Trust to PG.
File S1. Transcripts in bold are those also significantly affected by BSO alone BSO vs control, with a cutoff of FC 1. The log 2 -transformed gProcessed signals of the three biological replicates are shown.
The FC between the two groups indicated is expressed as log 2 ratio. File S2. In this study, the investigators propose to match the cysteine content of NAC and GSH and compare the effects of these two supplements, at two different doses, on markers of inflammation and oxidative stress.
Official Title Effects of GSH and N-Acetylcysteine on Inflammatory Markers Among Adults With CVD Risk. Stanford Investigator s. Christopher Gardner. Philip S. Tsao, PhD. Eligibility Inclusion Criteria: 1.
Intervention s : dietary supplement: Glutathione dietary supplement: N-Acetylcysteine other: Placebo. Not Recruiting. Contact Information Stanford University School of Medicine Pasteur Drive Stanford, CA Antonella Dewell Browse All Trials.
Browse Pediatric Trials Browse Trials Accepting Healthy Volunteers Cancer Clinical Trials Website. Health Care. Stanford Health Care Stanford Children's Health.
Stanford School of Medicine. Basic Science Departments Clinical Science Departments Academic Programs Vision. The present study indicates that normal GSH status is essential for proper PMNL migration to a site of infection, in that GSH depletion with chemicals decreases peritoneal PMNL infiltration after CLP.
It is important to note that sepsis depletes GSH enough to impair optimal peritoneal PMNL infiltration, as suggested by the fact that NAC augments peritoneal PMNL migration in CLP mice. Peritoneal bacterial colony-forming units of septic mice were increased by GSH depletion and decreased by NAC, which suggests that modulation of PMNL infiltration by GSH status significantly influenced this antibacterial response of the host.
Our findings that GSH might be important to PMNL migration to the primary site of infection or inflammation in sepsis and air pouch models apparently contradict most of the literature, which has indicated an anti-inflammatory role for GSH, and the ex vivo results shown in table 3.
According to the literature, GSH and NAC inhibit the production of several inflammatory cytokines and chemokines, including tumor necrosis factor TNF [ 1 ], IL-8, and monocyte chemoattractant protein-1 [ 2 ]; decrease membrane expression of chemokine receptors [ 3 ]; and inhibit activation of nuclear factor- κβ [ 22 ].
In agreement with the literature, when PMNL infiltration was measured to a distant site the lung rather than at the site of infection, a negative regulation of PMNL migration by GSH was demonstrated. In fact, in the same animals in which it decreased peritoneal PMNL migration, GSH depletion increased PMNL migration to the lung.
The effect of GSH depletion in CLP decreased PMNL at the site of infection, increased bacterial counts, and increased lung PMNL ultimately resulted in increased mortality. On the contrary, NAC decreased mortality by increasing PMNL at the site of infection, but not in the lung, and thus possibly preventing oxidative damage.
Although the decreased production of KC and possibly of other chemoattractants by GSH-depleting agents might explain our findings, the possibility that GSH depletion also impairs migration in response to chemokines was considered. In fact, when rhIL-8 was injected into the air pouch of GSH-depleted mice, a lower migratory response was observed.
Similar results from a different model were reported in a study that showed that DEM decreases intratracheal lipopolysaccharide LPS -induced pulmonary PMNL infiltration [ 23 ], which was explained by reduced intercellular adhesion molecule-1 ICAM-1 expression after DEM.
Thus, DEM impairs intratracheal LPS-induced [ 23 ] but not CLP-induced the present study pulmonary PMNL infiltration. The same discrepancy was observed when ICAM-1 was blocked: anti-ICAM-1 antibodies or ICAMtargeted gene disruption did not inhibit pulmonary PMNL infiltration after CLP [ 24 ] but did inhibit lung PMNL accumulation after local or intraperitoneal LPS [ 25 , 26 ].
Thus, it is possible that the differential regulation by GSH reported here might reflect different mechanisms, in terms of soluble mediators and adhesion molecules, implicated in LPS- and sepsisinduced pulmonary PMNL accumulation. In most studies that have reported that GSH inhibits cytokine or chemokine production, LPS, rather than a true infection, was used to trigger cytokine production.
The implication of the present study is that GSH depletion, which is often associated with sepsis, might be detrimental impairing host response to infection and by augmenting PMNLmediated lung damage.
By inhibiting inflammation but potentiating innate immunity mechanisms, treatment with thiol antioxidants and GSH-repleting agents might be preferred to treatments that inhibit overall PMNL migration.
In fact, there is a delicate balance between host defense and inflammation, and we are not aware of pharmacological approaches to selectively inhibit the latter. Studies that have used LPS or bolus injection of live bacteria have shown that inhibition of TNF has protective effects [ 27 , 28 ].
However, in a model of CLP-induced sepsis, anti-TNF antibodies can worsen the survival outcome [ 29 , 30 ]. Our data suggest that thiol antioxidants and GSH-repleting agents might help reorient PMNL migration in a way that is more favorable to the host and that this strategy can be complementary to supplementation with glutamine, which seems to play an important role in neutrophil function [ 31 ].
Google Scholar. Oxford University Press is a department of the University of Oxford. It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide.
Sign In or Create an Account. Navbar Search Filter The Journal of Infectious Diseases This issue IDSA Journals Infectious Diseases Books Journals Oxford Academic Mobile Enter search term Search.
Issues More Content Advance articles Editor's Choice Supplement Archive Cover Archive IDSA Journals Clinical Infectious Diseases Open Forum Infectious Diseases Publish Author Guidelines Submit Open Access Why Publish Purchase Advertise Advertising and Corporate Services Advertising Mediakit Reprints and ePrints Sponsored Supplements Branded Books Journals Career Network About About The Journal of Infectious Diseases About the Infectious Diseases Society of America About the HIV Medicine Association IDSA COI Policy Editorial Board Alerts Self-Archiving Policy For Reviewers For Press Offices Journals on Oxford Academic Books on Oxford Academic.
IDSA Journals. Issues More Content Advance articles Editor's Choice Supplement Archive Cover Archive IDSA Journals Clinical Infectious Diseases Open Forum Infectious Diseases Publish Author Guidelines Submit Open Access Why Publish Purchase Advertise Advertising and Corporate Services Advertising Mediakit Reprints and ePrints Sponsored Supplements Branded Books Journals Career Network About About The Journal of Infectious Diseases About the Infectious Diseases Society of America About the HIV Medicine Association IDSA COI Policy Editorial Board Alerts Self-Archiving Policy For Reviewers For Press Offices Close Navbar Search Filter The Journal of Infectious Diseases This issue IDSA Journals Infectious Diseases Books Journals Oxford Academic Enter search term Search.
Advanced Search. Search Menu. Article Navigation. Close mobile search navigation Article Navigation. Volume Article Contents Abstract. Materials and Methods. Journal Article. Glutathione Protects Mice from Lethal Sepsis by Limiting Inflammation and Potentiating Host Defense.
Pia Villa , Pia Villa. Oxford Academic. Alessandra Saccani. Antonio Sica. Pietro Ghezzi. Revision received:. PDF Split View Views. Select Format Select format. ris Mendeley, Papers, Zotero. enw EndNote. bibtex BibTex. txt Medlars, RefWorks Download citation. Permissions Icon Permissions.
Close Navbar Search Filter The Journal of Infectious Diseases This issue IDSA Journals Infectious Diseases Books Journals Oxford Academic Enter search term Search. Abstract Neutrophils have a dual role in sepsis—defending against infection and mediating organ failure.
Figure 1. Open in new tab Download slide. Figure 2. Table 1. Table 2. Table 3. N-acetylcysteine and glutathione as inhibitors of tumor necrosis factor production. Google Scholar Crossref. Search ADS. Antioxidants inhibit tumor necrosis factor-alpha mediated stimulation of interleukin-8, monocyte chemoattractant protein-1, and collagenase expression in cultured human synovial cells.
Google Scholar PubMed. OpenURL Placeholder Text.
Many local and systemic inflammatiob especially diseases that inflammatiin leading causes of death globally Glutatjione chronic obstructive pulmonary disease, atherosclerosis lnflammation ischemic heart disease Glutahhione stroke, cancer and inflammstion acute respiratory syndrome coronavirus 2 Glutathione and inflammation causing coronavirus disease 19 COVIDinvolve both, 1 oxidative stress Glutathion Glutathione and inflammation production of reactive Glutathione and inflammation species ROS that lower glutathione Glutathione and inflammation levels, and 2 inflammation. Glutathione and inflammation GSH tripeptide γ- L-glutamyl-L-cysteinyl-glycinethe most abundant water-soluble non-protein Glutathione and inflammation Glutathkone the Glutaathione 1—10 Boost antioxidant levels is fundamental for life by a sustaining the adequate redox cell signaling needed to maintain physiologic levels of oxidative stress fundamental to control life processes, and b limiting excessive oxidative stress that causes cell and tissue damage. GSH activity is facilitated by activation of the Kelch-like ECH-associated protein 1 Keap1 -Nuclear factor erythroid 2-related factor 2 Nrf2 -antioxidant response element ARE redox regulator pathway, releasing Nrf2 that regulates expression of genes controlling antioxidant, inflammatory and immune system responses. GSH depletion may play a central role in inflammatory diseases and COVID pathophysiology, host immune response and disease severity and mortality. Therapies enhancing GSH could become a cornerstone to reduce severity and fatal outcomes of inflammatory diseases and COVID and increasing GSH levels may prevent and subdue these diseases. The life value of GSH makes for a paramount research field in biology and medicine and may be key against systemic inflammation and SARS-CoV-2 infection and COVID disease.Glutathione and inflammation -
Effects of Glutathione an Antioxidant and N-Acetylcysteine on Inflammation Not Recruiting. Purpose The rationale for the potential role of antioxidants in the prevention of cardiovascular diseases CVD remains strong despite the disappointing results of recent trials with a few select antioxidant vitamins.
Glutathione GSH is one of the body's most powerful antioxidant agents but there is a surprising paucity of data on its use as an interventional therapy.
Glutathione, when taken orally, is immediately broken down into its constituent amino acids, of which cysteine is the only one to be essential.
Available cysteine is the critical determinant of intracellular GSH concentrations. N-acetyl cysteine NAC is an antioxidant supplement that has been used to provide a source of cysteine to replete GSH levels. By replenishing endogenous glutathione, it is possible that NAC would exert the same effect s as exogenous GSH.
However, there is a new delivery system, liposomal GSH, which keeps glutathione intact. In this study, the investigators propose to match the cysteine content of NAC and GSH and compare the effects of these two supplements, at two different doses, on markers of inflammation and oxidative stress.
Official Title Effects of GSH and N-Acetylcysteine on Inflammatory Markers Among Adults With CVD Risk. Stanford Investigator s. Christopher Gardner. Philip S. Tsao, PhD. Eligibility Inclusion Criteria: 1. Intervention s : dietary supplement: Glutathione dietary supplement: N-Acetylcysteine other: Placebo.
Not Recruiting. Contact Information Stanford University School of Medicine Pasteur Drive Stanford, CA Antonella Dewell Browse All Trials.
Browse Pediatric Trials Browse Trials Accepting Healthy Volunteers Cancer Clinical Trials Website. Health Care. Stanford Health Care Stanford Children's Health. Stanford School of Medicine. Basic Science Departments Clinical Science Departments Academic Programs Vision.
Glutathione synthetase constitute the second step forming GSH, also using ATP. Cellular GSH concentration regulates the function of glutamate cysteine ligase. Figure 4. Glutathione redox state is regulated, in part, by glutathione peroxidases, forming oxidized glutathione GSSG , and by a reaction catalyzed by glutathione reductase.
Glutathione is conjugated to substrates both through the action of the glutathione S-transferases and through non-enzymatic reactions.
Glutathione conjugates can be excreted from the cells by members of the ATP-binding cassette ABC transporter family. Glutathione is found in almost all cellular compartments, including the nucleus 5 , 54 , 64 — 68 Figures 2 , 4.
The GSH transport between the various cell compartments is vital to buffer reactive oxygen species ROS and facilitate redox signaling in order to control cell growth, development and defense, as well as regulate cell proliferation.
GSH is predominantly in its thiol-reduced form inside the cells, except in the lumen of the endoplasmic reticulum where it exists only in its GSSG form Figures 2 , 4. The GSH content existing in millimolar concentrations varies among different organs; liver being among organs with the highest content GSH content also varies among different areas of the same tissues; periportal hepatocytes may contain nearly twice the centrilobular concentration, enterocytes at the villus tip have a higher content than the crypts, and renal proximal tubular cells have more GSH than other parts of the nephron This difference in concentration is associated with the absence of catalase inside the mitochondria, what leaves GSH in charge of all inactivation of the hydrogen peroxide generated during the oxidative processes that occur in the mitochondrial matrix The concentration of GSH in the mitochondrial compartment is more important for cell survival than the GSH found in the cytosol.
Since mitochondria do not have the enzymes involved in the synthesis of GSH, all the GSH found in the mitochondrial compartment comes from the cytosol. A system transport present in the inner mitochondrial membrane, that involves dicarboxylate and 2-oxoglutarate anion transporters, allows the passage of negatively charged GSH from the cytosol to the mitochondria.
The first incorporates GSH into the mitochondria by inorganic phosphate exchange and the second by exchange of 2-oxoglutarate 27 , 28 , 64 Figures 2 , 4. While the greater amount of cellular reduced GSH is found in the cytosol and mitochondria, the endoplasmic reticulum becomes a reservoir of small concentrations of the oxidized form of GSH GSSG.
There is a preferential transport of GSSG from the cytosol to the endoplasmic reticulum to maintain an adequate environment for protein disulfide bond formation and protein folding 69 — There is little data about the concentrations of GSH in the nucleus and endoplasmic reticulum largely because of a lack of adequate techniques to accurately determine the GSH pool at those locations 15 , 69 , 72 , There are great variations in nuclear GSH concentration and its regulation mechanisms during the cell cycle since cells starting the proliferation phase have high levels of nuclear GSH, while resting cells have similar or lower GSH levels in the nucleus than in the cytoplasm 68 , 72 , High nuclear GSH concentrations are vital since increase in total GSH is necessary for the cells to progress from the G1- with low GSH levels to the S-phase; addition of GSSG causes the cell cycle to arrest at G1; and excessive and prolonged oxidation arrest cell cycle triggering cell death 68 , 72 , The synthesis, transport and catabolism of GSH occur in a series of enzymatic steps and transports of membrane that are collectively called γ -glutamyl cycle Figure 5 1 , 74 , The γ - glutamyl cycle was postulated by Meister 76 and it accounts for the GSH biosynthesis and degradation.
The GSH biosynthesis has been described previously. After its synthesis, GSH is transported to the intracellular compartments, mitochondria, endoplasmic reticulum and nucleus, but most of it is released through transporters toward the extracellular space.
In contrast to the synthesis, that occurs only intracellularly, the degradation or catabolic part of the GSH cycle, takes place partially extracellularly and partially inside cells. The extracellular degradation of GSH occurs on the surface of the cells that express the enzyme γ-glutamyl transpeptidase and the dipeptidases found in the external plasma membrane 1 Figure 5.
After the plasma membrane carrier-mediated GSH release from the cell, GSH becomes accessible to the active site of γ - glutamyl transpeptidase, which catalyzes the breakdown of the GSH γ - glutamyl bond forming two fractions: The γ-glutamyl fraction and the cysteinyl-glycine by transferring the γ-glutamyl fraction to an amino acid acceptor, forming γ-glutamyl-amino acid.
Once inside the cell, the γ-glutamyl-amino acid can be metabolized to release the amino acid and 5-oxoproline, which can then be converted into glutamate to be used in the synthesis of GSH.
On the other hand, also in the extracellular space, the cysteinyl-glycine fraction is split by the enzyme dipeptidase generating cysteine and glycine.
The cells incorporate cysteine and most of the intracellular cysteine is incorporated into the synthesis of GSH. Depending on the metabolic needs of the cell, the cysteine can be used for protein synthesis and part can be degraded to sulfate and taurine.
The cycle γ-glutamyl allows GSH to be used as a continuous source of cysteine. The γ-glutamyl amino acid is taken up by cells through a specific transport mechanism. Cysteinyl glycine is also taken up by cells. Inside the cell, the γ-glutamyl amino acid is hydrolyzed by γ-glutamyl cyclo-transferase and converted into oxoproline and a free amino acid.
Oxoproline is a cyclic form of glutamate and is converted into glutamate via oxoprolinase Figure 5. The γ-glutamyl cycle was initially postulated by Meister as a mechanism for amino acid transport However, this presents major problems.
The most important is the energetic one. The γ-glutamyl cycle requires the use of three ATP molecules per turn of the cycle. Thus, the uptake of an amino acid would require the use of three high-energy phosphate bonds. In favor of the cycle was the fact that addition of γ-glutamyl transpeptidase inhibitors in vivo caused a decrease in amino acid transfer into cells.
The γ - glutamyl amino acids or oxoproline could be signaling molecules to activate the transport of amino acids through membranes. Oxoproline catalytically activates the uptake of amino acids through the placental barrier, and the transfer of amino acids through the blood—brain barrier is activated by oxoproline 2 , Thus, the γ-glutamyl cycle, apart from explaining the synthesis and degradation of glutathione, may serve as a generator of signals to activate amino acid transport into cells 2 , GSH turnover may be considered as a multi-organ process.
In fact, in liver, an organ in which glutathione synthesis is most active, the degradation is very slow due to the very low activity of γ-glutamyl transpeptidase. In the kidney, however, γ-glutamyl transpeptidase is very high. Thus, the γ-glutamyl cycle may be considered as a multi-organ cycle in which the synthetic part occurs in liver and the catabolic part occurs in kidney amongst other tissues.
Figure 5. Cellular glutathione synthesis and recycling: The importance of the γ-glutamyl pathway. The degradation or catabolic part of the GSH cycle, takes place partially extracellularly and partially inside cells.
Following plasma membrane carrier-mediated GSH release from the cell, GSH becomes accessible to the active site of γ - glutamyl transpeptidase, which catalyzes GSH breakdown into γ-glutamyl fraction and cysteinyl-glycine by transferring the γ-glutamyl fraction to an amino acid acceptor, forming γ-glutamyl-amino acid.
The cysteinyl-glycine fraction is split by the enzyme dipeptidase generating cysteine and glycine. Cysteine can be used for protein synthesis and part can be degraded to sulfate and taurine.
Inside the cell, the γ-glutamyl amino acid is hydrolyzed by γ-glutamyl cyclo-transferase and converted into oxoproline, a cyclic form of glutamate converted into glutamate via oxoprolinase, and a free amino acid. Glutathione Samsonian mighty power is centered in the thiol sulfhydryl group of the cysteine amino acid.
GSH participates in numerous key processes where the thiol reducing potential is utilized. Several lung disorders are believed to be characterized by an increase in alveolar oxidant burden, potentially depleting alveolar and lung GSH.
Low GSH has been linked to abnormalities in the lung surfactant system and the interaction between GSH and antiproteases in the epithelial lining fluid of patients. Normal levels of intracellular GSH may exert a critical negative control on the elaboration of proinflammatory cytokines.
The increase of intracellular ROS is believed to correlate with the activation of nuclear factor NF -kappa B, a transcription activator linked to the elaboration of several cytokines Figure 6. There is now sufficient data to strongly implicate free radical injury in the genesis and maintenance of several lung disorders in humans.
This information is substantial and will help the development of clinical studies examining a variety of inflammatory lung disorders. Figure 6. Oxidative stress, reduced glutathione GSH and lung diseases.
Alveolar type I cells augment ROS production via toll-like receptors TLRs 1 and 2. Inflammation enhances neutrophil extracellular trap NET release and increases ROS production. ROS are counterbalanced by enzymes like superoxide dismutase SOD , catalase Cat , glutathione S-transferase GST , and glutathione peroxidase GPx to protect cells from oxidative damage caused by nicotinamide adenine-dinucleotide phosphate NADPH oxidase 2 NOX2 , superoxide O 2 — , hydrogen peroxide H 2 O 2 , and myeloperoxidase MPO.
Capillary neutrophils migrate to and from alveoli by trans- endothelial TEM and reverse transmigration rTEM , respectively. Inflammation can cause excessive ROS production in capillaries, red blood cell RBC dysfunction, thrombosis and alveolar damage. Inflammation-associated activated macrophages via TLRs reduce enzymes like SOD and Cat, among others, and activate NF-κB.
NOX2 activation increases ROS production that enhance NF-κB activation. Glutathione GSH precursors Cystine, cysteine, N-acetyl cysteine, NAC , and selenium Se restore GSH and GPx, respectively, to counteract the effects of ROS. MPO, nitric oxide NO , O 2 — , and H 2 O 2 through the Fenton and Haber-Weiss reactions that generate hydroxyl radicals, participate in ROS and RNS generation.
Lung disease-associated inflammation and apoptosis [ via TLRs and glycosaminoglycans GAGs ] enhance alveolar cell ROS production that via p38MAPK, NF- κB, and AP-1 activation, contribute to epithelial injury and further inflammation.
Administration of GSH precursors [cystine, cysteine, NAC; see 3 , 4 , and 5 ] facilitate GSH formation to reduce oxidative stress. Abbreviations: PRRs, pattern recognition receptors; ɣ-GCS, ɣ-glutamyl cysteine synthetase; DAMPs, damage associated molecular patterns; Prxs, peroxiredoxins; NAC, N-acetyl cysteine; ɣ-GT, ɣ-glutamyl transpeptidase; PAMPs, pathogen associated molecular patterns; LPC, lysophosphatidylcholine.
Oxidative stress and inflammation are considered fundamental mediators of chronic obstructive pulmonary disease COPD pathophysiology 77 — The lungs are directly exposed to tobacco smoke and air pollutants that are main sources of ROS. ROS directly cause lung damage as a result of DNA, lipid, carbohydrate, and protein alterations, and activate local inflammatory responses that contribute to COPD development and progression 79 — ROS can further activate epithelial cells and macrophages facilitating neutrophil, monocyte, and lymphocyte recruitment, and the recruited activated inflammatory cells subsequently enhance additional ROS generation, increasing the pro-oxidant burden 80 — The phosphocholine head group in phospholipids of normal healthy cell membranes is not accessible but, when cells are damaged and die, enhanced availability of lysophosphatidylcholine and disruption of the lipid bilayer expose phosphocholine residues to which CRP avidly binds These events lead to a state of persistent inflammation and chronic oxidative stress 82 — 85 , characterized by increased ROS production, reduced GSH peroxidase activity, selenium deficiency and reduced GSH levels 80 — Patients with decreased GSH and increased oxidative stress also showed increased neutrophil influx and IL-8 levels Alveolar macrophages derived from circulating monocytes recruited into the lungs by monocyte chemotactic factors produced by lung cells are increased fold in COPD patients and release ROS as superoxide anions and hydrogen peroxide Antioxidant therapies should be effective in preventing COPD disease progression and exacerbations.
Although prolonged treatment with oral N-acetylcysteine NAC prevents acute exacerbations of chronic bronchitis, it remains controversial for the treatment of COPD 91 , — A combination of antioxidants including thiol-based antioxidants, mitochondria-targeted antioxidants and Nrf2 activators should be more effective in the treatment of COPD patients In acute respiratory distress syndrome ARDS , there is extensive overproduction of free radicals and reduced extracellular and intracellular GSH leading to oxidative cell damage ROS such as hydrogen peroxide and hypochlorous acid may play a key role in the pathogenesis of the acute lung injury It has been shown that alveolar epithelial lining fluid of patients with ARDS is deficient in total GSH compared to normal subjects , and neutrophil-mediated oxidants release leads to GSH deficiency and lung cell injury The global antioxidant capacity of the epithelial lining fluid, despite an increase in single antioxidant compounds, seems unable to fully counterbalance the increased oxidative burden NAC benefited ARDS patients as evidenced by intracellular inside red blood cells and extracellular plasma antioxidant defense biomarkers and outcome.
A depressed antioxidant defense and dysfunctional iron regulation in ARDS might cause greater inflammation and anemia Glutathione is an important antioxidant in the lungs, but its concentration is low in the airways of patients with cystic fibrosis, since GSH is transported into the airways by the cystic fibrosis transmembrane conductance regulator, which is mutated in cystic fibrosis patients The concentration of GSH that is normally about μM in the epithelial lining fluid, over a fold higher than in plasma, is low in the airways of patients with cystic fibrosis from an early age — Extracellular glutathione S-transferase omega-1, a cytosolic enzyme that modulates the S-thiolation status of intracellular factors involved in the inflammatory response, and its polymorphisms have been associated with an increased risk to develop COPD and could have a biological and clinical significance in cystic fibrosis Low GSH, neutrophil infiltration, myeloperoxidase activity and inflammation increase oxidative stress overwhelming the antioxidant defense, and hypochlorous acid mediated GSH oxidation and its attachment to proteins contribute to further GSH deficiency The lack of efficacy of inhaled GSH in patients with cystic fibrosis could be explained by the high concentrations of the GSH-degrading enzyme γ-glutamyltransferase present in lung fluids of those patients — , and then, the use of precursors of GSH synthesis like NAC and cystine could be more effective in the synthesis of GSH Lack of oral GSH supplementation effects upon growth or changes in serum or fecal inflammatory markers in children with cystic fibrosis with pancreatic insufficiency could be probably explained by the inability of the cells to uptake extracellular GSH to be used inside the cells.
Decreased GSH content in the apical fluid in cystic fibrosis could be the result of abnormal GSH transport associated with a defective cystic fibrosis transmembrane conductance regulator as mentioned previously Glutathione-S-transferase π GSTP that participates in the conjugation of GSH to reactive cysteines S-glutathionylation seems to play an important role in idiopathic pulmonary fibrosis lung fibrogenesis, since GSTP immunoreactivity is increased in the lungs of idiopathic pulmonary fibrosis patients, notably within type II epithelial cells , GSTP inhibition via the airways may be a novel therapeutic strategy for the treatment of idiopathic pulmonary fibrosis , The use of GSH precursors like N-acetyl cysteine, enhancers of nuclear factor erythroid 2-related factor 2 Nrf2 like sulforaphane, melatonin, and many more molecules involved in antioxidant defense were proposed as supplementation of other idiopathic pulmonary fibrosis therapies Inhaled nebulized or aerosolized reduced GSH to augment the deficient GSH levels of the lower respiratory tract has been used effectively in numerous pulmonary diseases and respiratory conditions like HIV seropositive individuals, cystic fibrosis and idiopathic pulmonary fibrosis, among others — GSH has clearly a regulatory role in inflammation and immunity GSH then directs the migration of inflammatory polymorphonuclear neutrophils away from the lung, where they cause ARDS, and toward the site of infection, where they kill microorganisms.
As a result, it develops more immunity and less inflammation, with the concomitant increased survival; in addition, GSH becomes not just an inhibitor of inflammation but a regulator of innate immunity in a direction that benefits the host Cardiovascular diseases are the leading causes of death in the US compared to any other cause Cardiovascular complications are thought to result from increased free radical levels that impair redox homeostasis, that represents the interaction between oxidative stress and reductive stress.
A prolonged oxidative or reductive stress will alter the homeostatic redox mechanism to cause cardiovascular complications. GSH, the most abundant antioxidant in the heart, plays a fundamental role in normalizing a redox homeostatic mechanism that was shifted toward oxidative or reductive stress.
This may lead to impairment of cellular signaling mechanisms and accumulation of misfolded proteins causing proteotoxicity associated with cardiac dysfunction — A higher level of oxidative stress as evidenced by elevated plasma malondialdehyde levels and low levels of GSH, α-tocotrienol and GSH peroxidase activity in patients under 45 years old may play a role in the development of premature coronary artery disease and be potential biomarkers for premature coronary artery disease Similarly, coronary artery disease patients with single, double, or triple-vessel stenosis and patients with acute coronary syndrome had a significant increase in malondialdehyde levels and the percentage of malondialdehyde release, associated with a marked decrease in GSH concentration, total antioxidant capacity and erythrocyte GSH peroxidase activity compared with controls Interestingly, differences in prooxidative parameters were more profound in acute coronary syndrome patients compared with coronary artery disease patients indicating that the acute form of coronary artery disease is more susceptible to oxidative damage, suggesting that use of antioxidant therapy may be warranted to reduce oxidative stress in this disorder Glutathione might inhibit the effects of cerebral infarction and enhance antiapoptotic signaling after ischemic stroke, suggesting that GSH may be a potent therapeutic antioxidant that can attenuate severe pathologies after ischemic stroke, and stimulating GSH synthesis through administration of GSH precursors and micronutrients like selenium can optimize GSH and GSH peroxidase for optimal antioxidant defense in cerebral ischemia , Low total GSH and high homocysteine levels are considered as novel risk markers for acute stroke severity, and low total and reduced GSH levels may be potential risk markers for stroke severity and insufficient functional independence in large-artery atherosclerosis , Since GSH is the final product of the homocysteine metabolism in the transsulfuration pathway by transferring sulfur from homocysteine to cysteine, a deficiency in transsulfuration pathway leads to excessive homocysteine production hyperhomocysteinemia and reduced GSH synthesis , Homocysteine is a sulfur-containing amino acid tightly involved in methionine metabolism.
Indeed, if there is a methionine deficit, homocysteine can be re-methylated to form methionine, and if there is an adequate amount of methionine, homocysteine is used to produce cysteine N-acetyl-cysteine administration supplies the cysteine necessary for GSH synthesis and concomitantly reduces hyperhomocysteinemia, improving GSH peroxidase activity and reducing oxidative stress Furthermore, the well documented efficacy of combined folic acid, B6, and Bvitamin supplementation to reduce hyperhomocysteinemia could enhance GSH activity and reduce oxidative stress Recently, it was shown that cysteine uptake via excitatory amino acid carrier 1 suppresses ischemia-induced neuronal death through promotion of hippocampal GSH synthesis in ischemic animal models Atherosclerosis represents a state of intense oxidative stress characterized by vascular wall lipid and protein oxidation that contributes to chronic inflammation within the arterial wall, in which CRP is a major player Figure 7.
The balance of the different CRP isoforms, monomeric mCRP or native pentameric nCRP within the plaque determines the preponderance of a proinflammatory or anti-inflammatory effect, respectively CRP is synthesized in smooth muscle cells of atherosclerotic lesions with active disease, foam cells, macrophages, lymphocytes, monocytes, and endothelial cells within the atherosclerotic plaque — CRP binds and aggregates oxidized low-density lipoprotein ox-LDL and enhances macrophage oxLDL uptake, promoting mitogen-activated protein kinase activation required for foam cell formation OxLDL enhances toll like receptor 4 expression further facilitating foam cell formation and development and progression of atherosclerosis , CRP binding to oxLDL and apoptotic cells occurs through phosphorylcholine, and binding to this ligand starts phagocytosis , , — Pentameric nCRP and CRP peptides 77—82, —, and — can control the inflammatory response resolving inflammation by reducing inflammatory cell endothelial adhesion and tissue migration, and the described CRP-mediated enhanced monocyte chemotaxis could be explained by local generation of mCRP , Foam cell formation during atherogenesis could be also explained in part by uptake of CRP-opsonized native LDL Pentameric nCRP does not possess intrinsic proinflammatory properties, while nnCRP and mCRP do , The mCRP isoform, unlike nCRP, has a stimulatory effect on platelets, facilitates thrombus growth through platelet stimulation, and is the more potent reagent, both increasing monocyte activation and ROS production, generated through myeloperoxidase-mediated respiratory burst and raft-associated reduced nicotinamide adenine dinucleotide phosphate NADPH -oxidase during oxLDL-mediated foam cell formation , , — ROS activity in the vessel wall contributes to the formation of oxidized LDL, a major contributor to the pathogenesis of atherosclerosis , Thrombus formation and the subsequent activation of the coagulation cascade with final generation of fibrin is facilitated by the mCRP-mediated enhancement of tissue factor on the endothelial cell surface, platelet aggregation and thrombus growth , Figure 7.
OxLDL components and their interaction with toll-like receptors TLRs 2 and 4, CD36 and other cellular receptors further mediate thromboinflammation enhancing tissue and organ damage culminating in organ failure, i. Figure 7. Oxidative stress, reduced glutathione GSH and atherosclerosis. Native C-reactive protein nCRP , a pattern recognition receptor produced in the liver, macrophages, lymphocytes, smooth muscle cells SMC , and other cells, promotes inflammation through monomeric CRP mCRP enhancing intimal oxidative stress.
Oxidized ox LDL binds macrophage toll-like receptor TLR 4 and facilitates nicotinamide adenine dinucleotide phosphate NADP H oxidase 2 Nox2 activity and superoxide O 2 — production causing cysteine oxidation, disulfide bridge formation and S-glutathionylation.
OxLDL bound to TLRs 2 and 4 promotes foam cell formation and activates transcription factors like nuclear factor NF -κB facilitating cytokine storm and hyperinflammation. Excessive mitochondrial reactive oxygen species ROS generation further enhances cytokine production.
CRP nCRP, mCRP can facilitate macrophage and neutrophil uptake of apoptotic cells through Fcγ and Fcα receptors, respectively FcRs. Oxidative stress also activates the Kelch-like ECH-associated protein 1 Keap1 -Nuclear factor erythroid 2-related factor 2 Nrf2 -antioxidant response element ARE redox regulator pathway in monocytes [see 3 and macrophages 2 ], releasing Nrf2 to regulate the expression of genes that control antioxidant enzymes like glutathione S-transferase GST , facilitating glutathione GSH activity.
Macrophages, T-lymphocytes, neutrophils and SMCs can generate mCRP increasing inflammation. TLR 4-mediated oxLDL-binding to platelets promotes thrombosis; mCRP binding to lipid rafts and FcγRs enhances inflammation; and endothelial activation allows intimal cell migration.
GSH enhancement and Nrf2 activation augment immunity and reduce atherosclerosis. The strong role of severe oxidative stress, reduced antioxidant defenses like GSH with increased lipid peroxidation and malondialdehyde generation , lipid, protein and DNA oxidation with increased apoptosis and necrosis in atherosclerosis as a major cause of cardiovascular diseases and stroke, supports the use of complementary and alternative medicines, dietary supplements, and antioxidants with hardly any adverse effect, able to restore homeostasis reversing oxidative stress Enhancing GSH synthesis, selenium levels and redox-active selenoproteins, and activating Nrf2 and other antioxidant enzymes will strengthen the cardiovascular antioxidant defense.
Phenolic compounds like phenolic acids, flavonoids, lignans and tannins can limit LDL oxidation and foam cell formation Selenium is an essential micronutrient that modulates cardiovascular functions via its incorporation into selenoproteins as the amino acid selenocysteine , Intravenous reduced GSH supplementation reverses endothelial dysfunction in patients with atherosclerosis enhancing NO activity and NO-mediated vasodilation GSH stores and transports cysteine, and cysteine forms less diffusion-limited NO adducts that may transport NO to reach sites within vascular smooth muscle cells and platelets , Since GSH is not carried inside the cell, exogenously administered GSH is most likely to act by increasing plasma GSH levels reducing luminal oxidative stress and increasing NO bioavailability in patients with endothelial dysfunction Considering the paramount importance of oxLDL in the pathogenesis of atherosclerosis, it is reasonable to evaluate the role of antioxidants in the treatment of the disease as adjuvant strategies to lipid-lowering or anti-inflammatory therapies designed to reduce the risk of cardiovascular disease Since oxidation participates as an essential messenger of cellular signaling pathways, treatment of oxidative stress needs to consider maintaining that physiologic threshold , Nuclear factor erythroid 2-related factor 2 plays a fundamental role in the response to oxidative stress and xenobiotic metabolism and detoxification, and the Nrf2 signaling pathway is intimately associated with development of atherosclerosis.
During development and progression of atherosclerosis, Nrf2 signaling modulates many physiological and pathophysiological processes, like regulation of lipid homeostasis, CD36 gene expression regulation, foam cell formation, macrophage polarization, immunity regulation Th2 differentiation and inhibition of pro-inflammatory gene expression through NFκB down-regulation , redox regulation and inflammation, improvement of endothelial dysfunction, as well as GSH synthesis and utilization — Antioxidant pathways induced by NRF2 include enzymes for the reduced GSH synthesis, utilization, and regeneration.
Glutamate-cysteine ligase catalytic and modulator subunits as well as GSH synthetase are the three NRF2 targets involved in the GSH synthesis The redox cycling enzymes thioredoxin, thioredoxin reductase, sulfiredoxin, peroxiredoxin, GSH peroxidase, superoxide dismutase 1, and catalase, and several GSH S-transferases, which are the enzymes mediating the elimination of ROS, are all Nrf2 targets Nrf2 displays both pro- and anti-atherogenic effects in experimental animal models, and the Nrf2 pathway becomes a promising target for atherosclerosis prevention Macrophage Nrf2 activates genes encoding CD36, heme oxygenase-1 and other stress proteins in response to oxLDLs and other byproducts of lipid peroxidation Nrf2 depletion in macrophages leads to increased foam cell formation, increases the M1 inflammatory phenotype with enhanced expression of pro-inflammatory monocyte chemoattractant protein-1 and interleukin-6, and aggravates atherosclerosis , Nrf2 improves endothelial function by resisting oxidative stress and mitochondrial damage, thereby delaying atherosclerosis ; and treatment with sulforaphane, a dietary antioxidant, activates Nrf2 and suppresses p38—VCAM-1 signaling, and may provide a novel therapeutic strategy to prevent or reduce atherosclerosis This intense inflammation is associated with damaging systemic events like oxidative stress, dysregulation of iron homeostasis, hypercoagulability and thrombus formation, acute respiratory distress syndrome, uncontrolled inflammation and organ failure — Figure 8.
Several viral infections, and the progression of virus-induced diseases, especially those associated with COVID, are characterized by an alteration in the intracellular redox balance 6. This imbalance disallows reactive intermediate detoxification by the cell biological systems.
ROS production and associated inflammation are closely related to aging and numerous chronic diseases as diabetes, cardiovascular atherosclerosis-related diseases , and respiratory diseases, known risk factors for developing severe illness and death in patients with SARS-CoV-2 and COVID disease.
Figure 8. Severe acute respiratory syndrome coronavirus 2 SARS-CoV-2 pulmonary infection, oxidative stress and antioxidant defenses. Infected cells activate nuclear factor NF -κB and release cytokines like interleukin IL SARS-CoV-2 infection can cause excessive ROS production in capillaries, red blood cell RBC dysfunction, thrombosis and alveolar damage.
SARS-CoVinfected macrophages via ACE2 and TLRs reduce enzymes like SOD and Cat, among others, and activate NF-κB. Abbreviations: TMPRSS2, Transmembrane protease Serine 2; PRPs, pattern recognition proteins. Reprinted from Labarrere and Kassab Atherosclerosis, a chronic inflammatory disease, may be an ideal environment for the high viral replication capabilities of SARS-CoV-2 in human cells, enhancing hyper-inflammation secondary to immune system dysregulation Figure 9 that leads to adverse outcomes, as shown in patients with cardiovascular risk factors , In a vicious circle, feeding itself, SARS-CoV-2 may aggravate the evolution of atherosclerosis as a result of excessive and aberrant plasmatic concentration of cytokines — Atherosclerosis progression, as a chronic inflammatory mechanism, is characterized by immune system dysregulation associated with increased pro-inflammatory cytokine production, including interleukin 6 IL-6 , tumor necrosis factor-α TNF-α , and IL-1β, as well as pattern recognition receptor proteins like CRP , — CRP, an active regulator of host innate immunity, is a biomarker of chronic inflammatory conditions and severe COVID disease, including lung and atherosclerotic disease progression; strongly predicts the need for mechanical ventilation; and may guide intensification of treatment of COVIDassociated uncontrolled inflammation 99 , , , , , — Macrophage activation and foam cell formation may explain the elevated CRP serum levels and contribute to disease progression Figure 9.
CRP-mediated inflammation in atherosclerosis during SARS-CoV-2 infection may be related to the presence of mCRP in the lesions , , , , — The affinity of SARS-CoV-2 for ACE2 receptors makes the virus prone to cause vascular infection that could explain atherosclerosis progression and arterial and venous thrombosis , Endothelial injury generated directly by intracellular viral replication and by ACE2 downregulation, exposing cells to angiotensin II in the absence of the modulator effects of angiotensin 1—7 , , and vascular chronic inflammation promoting the development of tissue macrophages overloaded by cholesterol foam cells , both increase the possibility of acquiring a severe COVID infection , , , , , Figure 9.
Severe acute respiratory syndrome coronavirus-2 SARS-CoV-2 enhances oxidative stress and atherosclerosis progression. Native C-reactive protein nCRP , a marker of severe SARS-CoV-2 produced in liver, macrophages, lymphocytes, smooth muscle cells SMC and other cells, promotes inflammation through monomeric CRP mCRP enhancing intimal oxidative stress.
SARS-CoV-2 binds macrophage toll-like receptor TLR 4 and facilitates nicotinamide adenine dinucleotide phosphate NADP H oxidase 2 Nox2 activity and superoxide O 2 — production causing cysteine oxidation, disulfide bridge formation and S-glutathionylation.
SARS-CoV-2 can bind TLRs 2 and 4 and activate transcription factors like nuclear factor NF -κB facilitating cytokine storm and hyperinflammation.
CRP nCRP, mCRP can facilitate macrophage and neutrophil uptake of SARS-CoVinfected apoptotic cells through Fcγ and Fcα receptors, respectively FcRs.
TLR 4-mediated SARS-CoVbinding to platelets promotes thrombosis, mCRP binding to lipid rafts and FcγRs enhances inflammation and endothelial activation allows intimal cell migration. In most diseases, ROS appear to have a direct connection with inflammaging and cell senescence, and oxidative stress and inflammaging increase the aging-related phenotype, and induce and aggravate the inflammatory response, creating a chronic state of systemic inflammation — All chronic diseases, including COVID with the long-COVIDsyndrome , are characterized by the presence of persistent chronic inflammation and sustained generation of reactive oxygen and nitrogen species that when confronted with inadequate antioxidant defenses likely leading components of anti-inflammaging precipitate excessive oxidative stress.
The demand for detailed analysis of the pathogenesis and clinical course of chronic diseases and viral diseases like COVID, as well as the use of efficacious therapies with minimal or no side effects are paramount.
Here we present the antioxidant GSH as a potential unexplored way for further investigation as intervention to counteract inflammaging, premature inflammaging, inflammatory diseases and long-COVIDsyndrome, since GSH levels are correlated with tissue and organ damage, disease severity and progression, and disease outcome — , , Enhancing GSH, mainly through NAC, GSH precursors rich in cysteine whey protein, whey protein isolate rich in cysteine or pro-GSH compound administration, becomes a potential treatment option for inflammatory diseases by reducing oxidative stress and cytokine expression especially in diabetic patients that also are at risk of more severe COVID disease GSH dysregulation might cause global immune cell autophagy decline with increased generation of proinflammatory cytokines in aging, further provoked by mitochondrial ROS signaling Glutamine, glycine, N-acetylcysteine, selenium, whey protein isolates with bonded cysteine, GSH and pro-GSH supplementation improves GSH deficiency, oxidative stress, mitochondrial dysfunction, inflammation, insulin resistance, endothelial dysfunction, genotoxicity, muscle strength, cognition and surfactant regeneration — A combination of vitamin D and L-cysteine administration significantly augmented GSH levels and lowered oxidative stress and inflammation , Maintaining an adequate GSH redox status and hydroxy-vitamin D levels will have the potential to reduce oxidative stress, enhance immunity and diminish the adverse clinical consequences of COVID especially in African American communities having glucosephosphate dehydrogenase G6PD deficiency, enzyme necessary to prevent GSH exhaustion and depletion 6 , , In normal red blood cells, pentose phosphate pathway and glycolysis are enhanced and G6PD is sufficient to produce NADPH efficiently for GSSG reduction and maintenance of GSH pool G6PD-deficient cells are unable to generate enough NADPH under the condition of severe thiol depletion and GSH biosynthesis and methionine cycle are upregulated at the expense of ATP but fail to compensate for GSH depletion Severe acute respiratory syndrome coronavirus 2 can sequester mitochondria and replicate within them aging those vital organelles weakening immunity; facilitating over-stimulated or sustained inflammatory responses with interferon and cytokine release, influencing ROS production, iron storage, platelet coagulability, cytokine production stimulation, regulation of fission and fusion, mitochondrial biogenesis, and interference of apoptosis and mitophagy — By affecting all these cellular functions already impaired in aging individuals it could explain why older, comorbid patients have the most severe outcomes with COVID and stimulate the use of GSH and Nrf2 enhancers as well as develop new therapies to protect mitochondria.
In a patient that is overloaded with cytokine storm, the best way to fortify the immune system would be to supply it with reduced GSH, since reduced GSH is already able to provide reducing equivalents from its thiol group.
This is particularly relevant when we consider GSH pathways, as well as their transcriptional regulator Nrf2, for proliferation, survival and function of T cells, B cells and macrophages , The value of GSH and nutritional strategies like amino acids, vitamins, minerals, phytochemicals, sulforaphane to enhance cellular Nrf2, and other supplements used to restore GSH levels — as adjunct treatments for all inflammatory diseases including SARS-CoV-2 infection needs to be further emphasized.
Reducing the levels of proinflammatory molecules like mCRP and nnCRP , will further reduce the detrimental effects of inflammaging.
Reestablishing the cellular metabolic homeostasis in inflammatory diseases as well as SARS-CoV-2 infection and COVID disease especially in the lungs and cardiovascular system, could become paramount to balance altered innate and adaptive immunity and cell function and reduce morbimortality — CL and GK participated in the design, writing, and final corrections of the manuscript.
Both authors contributed to the article and approved the submitted version. This is an open-access article distributed under the terms of the Creative Commons Attribution CC-BY License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers.
Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.
Meister A, Anderson ME. Annu Rev Biochem. doi: PubMed Abstract CrossRef Full Text Google Scholar. Sastre J, Pallardo FV, Viña J. Handb Environ Chem. CrossRef Full Text Google Scholar. Lu SC. Glutathione synthesis. Biochim Biophys Acta.
Meister A. On the discovery of glutathione. Trends Biochem Sci. Marí M, de Gregorio E, de Dios C, Roca-Agujetas V, Cucarull B, Tutusaus A, et al.
Mitochondrial glutathione: recent insights and role in disease. Polonikov A. Endogenous deficiency of glutathione as the most likely cause of serious manifestations and death in COVID patients. ACS Infect Dis. Silvagno F, Vernone A, Pescarmona GP.
The role of glutathione in protecting against the severe inflammatory response triggered by COVID Forman HJ, Zhang H, Rinna A. Glutathione: overview of its protective roles, measurement, and biosynthesis. Mol Aspects Med.
De Rey-Pailhade MJ. C R Hebd Séances Acad Sci. Google Scholar. Hopkins FG. On an autoxidisable constituent of the cell.
Biochem J. On glutathione: a reinvestigation. J Biol Chem. Kendall EC, Mason HL, McKenzie BF. A study of glutathione.
Determination of the structure of glutathione. Harington CR, Mead TH. Synthesis of glutathione. Kosower EM, Kosower NS.
Lest I forget thee, glutathione. Ballatori N, Krance SM, Notenboom S, Shi S, Tieu K, Hammond CL. Glutathione dysregulation and the etiology and progression of human diseases. Biol Chem. Jones DP, Carlson JL, Mody VC, Cai J, Lynn MJ, Sternberg P. Redox state of glutathione in human plasma.
Free Radic Biol Med. Koehler CM, Beverly KN, Leverich EP. Redox pathways of the mitochondrion. Antioxid Redox Signal. Han D, Hanawa N, Saberi B, Kaplowitz N. Mechanisms of liver injury.
Role of glutathione redox status in liver injury. Am J Physiol Gastrointest Liver Physiol. Owen JB, Butterfield DA.
In: Bross P, Gregersen N editors. Methods in molecular biology, protein misfolding and cellular stress in disease and aging: concepts and protocols.
Sreekumar PG, Ferrington DA, Kannan R. Glutathione metabolism and the novel role of mitochondrial GSH in retinal degeneration. Tomin T, Schittmayer M, Birner-Gruenberger R. Addressing glutathione redox status in clinical samples by two-step alkylation with N-ethylmaleimide isotopologues.
Zitka O, Skalickova S, Gumulec J, Masarik M, Adam V, Hubalek J, et al. Redox status expressed as GSH:GSSG ratio as a marker for oxidative stress in paediatric tumour patients. Oncol Lett. Giustarini D, Tsikas D, Colombo G, Milzani A, Dalle-Donne I, Fanti P, et al.
Pitfalls in the analysis of the physiological antioxidant glutathione GSH and its disulfide GSSG in biological samples: an elephant in the room. J Chromatogr B Analyt Technol Biomed Life Sci. Meredith MJ, Reed DJ. Status of the mitochondrial pool of glutathione in the isolated hepatocyte.
Fernández-Checa JC, Kaplowitz N, García-Ruiz C, Colell A, Miranda M, Marí M, et al. GSH transport in mitochondria: defense against TNF-induced oxidative stress and alcohol-induced defect. Hwang C, Sinskey AJ, Lodish HF. Oxidized redox state of glutathione in the endoplasmic reticulum.
Yuan L, Kaplowitz N. Glutathione in liver diseases and hepatotoxicity. Scirè A, Cianfruglia L, Minnelli C, Bartolini D, Torquato P, Principato G, et al.
Glutathione compartmentalization and its role in glutathionylation and other regulatory processes of cellular pathways. Schafer FQ, Buettner GR.
Jones DP. Redefining oxidative stress. Kemp M, Go Y-M, Jones DP. Esposito F, Agosti V, Morrone G, Morra F, Cuomo C, Russo T, et al. Inhibition of the differentiation of human myeloid cell lines by redox changes induced through glutathione depletion.
Hansen JM, Carney EW, Harris C. Altered differentiation in rat and rabbit limb bud micromass cultures by glutathione modulating agents.
Hansen JM, Harris C. Glutathione during embryonic development. Nkabyo YS, Ziegler TR, Gu LH, Watson WH, Jones DP. Glutathione and thioredoxin redox during differentiation in human colon epithelial Caco-2 cells. Kim J-M, Kim H, Kwon SB, Lee SY, Chung S-C, Jeong D-W, et al.
Intracellular glutathione status regulates mouse bone marrow monocyte-derived macrophage differentiation and phagocytic activity. Biochem Biophys Res Commun. Huh Y-J, Kim J-M, Kim H, Song H, So H, Lee SY, et al.
Regulation of osteoclast differentiation by the redox-dependent modulation of nuclear import of transcription factors. Cell Death Differ. Hammond CL, Lee TK, Ballatori N. Novel roles for glutathione in gene expression, cell death, and membrane transport of organic solutes.
J Hepatol. Ballatori N, Hammond CL, Cunningham JB, Krance SM, Marchan R. Toxicol Appl Pharmacol. Won J-S, Singh I. Sphingolipid signaling and redox regulation. Garcia-Ruiz C, Fernández-Checa JC. Redox regulation of hepatocyte apoptosis. J Gastroenterol Hepatol.
Sykes MC, Mowbray AL, Jo H. Reversible glutathiolation of caspase-3 by glutaredoxin as a novel redox signaling mechanism in tumor necrosis factor-alpha-induced cell death.
Circ Res. Cerutti PA. Prooxidant states and tumor promotion. Townsend DM, Tew KD, Tapiero H. The importance of glutathione in human disease.
Biomed Pharmacother. Liu H, Wang H, Shenvi S, Hagen TM, Liu R-M. Glutathione metabolism during aging and in Alzheimer disease. Ann N Y Acad Sci. Estrela JM, Ortega A, Obrador E. Glutathione in cancer biology and therapy.
Crit Rev Clin Lab Sci. Franco R, Schoneveld OJ, Pappa A, Panayiotidis MI. The central role of glutathione in the pathophysiology of human diseases. Arch Physiol Biochem.
Kinnula VL, Vuorinen K, Ilumets H, Rytilä P, Myllärniemi M. Thiol proteins, redox modulation and parenchymal lung disease. Curr Med Chem. Reynolds A, Laurie C, Mosley RL, Gendelman HE. Oxidative stress and the pathogenesis of neurodegenerative disorders.
Int Rev Neurobiol. Seifried HE. Oxidative stress and antioxidants: a link to disease and prevention? J Nutr Biochem.
Vali S, Mythri RB, Jagatha B, Padiadpu J, Ramanujan KS, Andersen JK, et al. Valko M, Leibfritz D, Moncol J, Cronin MTD, Mazur M, Telser J. Free radicals and antioxidants in normal physiological functions and human disease.
Int J Biochem Cell Biol. Khanfar A, Al Qaroot B. Could glutathione depletion be the trojan horse of COVID mortality? Eur Rev Med Pharmacol Sci. Denzoin Vulcano LA, Soraci AL, Tapia MO. Homeostasis del glutatión. Acta Bioquím Clín Latinoam.
Regulation of glutathione synthesis. Kaplowitz N, Aw TY, Ockhtens M. The regulation of hepatic glutathione. Ann Rev Pharmacol Toxicol.
Pastore A, Federici G, Bertini E, Piemonte F. Analyses of glutathione: implication in redox and detoxification. Clin Chim Acta. Camera E, Picardo M.
Analytical methods to investigate glutathione and related compounds in biological and pathological processes. Seelig GF, Meister A. Glutathione biosynthesis: γ-glutamylcysteine synthetase from rat kidney. Methods Enzymol. Huang CS, Anderson ME, Meister A. Amino acid sequence and function of the light subunit of rat kidney γ-glutamylcysteine synthetase.
Franklin CC, Backos DS, Mohar I, White CC, Forman HJ, Kavanagh TJ. Structure, function, and post-translational regulation of the catalytic and modifier subunits of glutamate cysteine ligase. Grant CM, Maciver FH, Dawes IW. Glutathione synthetase is dispensable for growth under both normal and oxidative stress conditions in the yeast Saccharomyces cerevisiae due to an accumulation of the dipeptide gamma-glutamylcysteine.
Mol Biol Cell. Circu ML, Aw TY. Glutathione and apoptosis. Free Radic Res. Marí M, Morales A, Colell A, García-Ruiz C, Fernández-Checa JC. Mitochondrial glutathione, a key survival antioxidant. Glutathione and modulation of cell apoptosis. Markovic J, Borrás C, Ortega A, Sastre J, Viña J, Pallardó FV.
Glutathione is recruited into the nucleus in early phases of cell proliferation. Markovic J, Mora NJ, Broseta AM, Gimeno A, de-la-Concepción N, Viña J, et al.
The depletion of nuclear glutathione impairs cell proliferation in 3t3 fibroblasts. PLoS One. Diaz-Vivancos P, Wolff T, Markovic J, Pallardó FV, Foyer CH. A nuclear glutathione cycle within the cell cycle. Chakravarthi S, Jessop CE, Bulleid NJ.
The role of glutathione in disulphide bond formation and endoplasmic-reticulum-generated oxidative stress. EMBO Rep. Feige MJ, Hendershot LM. Disulfide bonds in ER protein folding and homeostasis. Curr Opin Cell Biol. Ellgaard L, Sevier CS, Bulleid NJ. How are proteins reduced in the endoplasmic reticulum?
García-Giménez JL, Markovic J, Dasí F, Queval G, Schnaubelt D, Foyer CH, et al. Nuclear glutathione. Pallardó FV, Markovic J, García JL, Viña J. Role of nuclear glutathione as a key regulator of cell proliferation. Mol Asp Med.
Griffith OW, Bridges RJ, Meister A. Formation of gamma-glutamycyst e ine in vivo is catalyzed by gamma-glutamyl transpeptidase. Proc Natl Acad Sci USA. Viña JR, Palacin M, Puertes IR, Hernandez R, Viña J.
Role of the y-glutamyl cycle in the regulation of amino acid translocation. Am J Physiol-Endocrinol Metab. On the enzymology of amino acid transport: transport in kidney and probably other tissues is mediated by a cycle of enzymic reactions involving glutathione.
Zuo L, Wijegunawardana D. Redox role of ROS and inflammation in pulmonary diseases. Adv Exp Med Biol. McGuinness AJ, Sapey E.
Oxidative stress in COPD: sources, markers, and potential mechanisms. J Clin Med. Kirkham PA, Barnes PJ.
Oxidative stress in COPD. Zinellu E, Zinellu A, Pau MC, Piras B, Fois AG, Mellino S, et al. Glutathione peroxidase in stable chronic obstructive pulmonary disease: a systematic review and meta-analysis.
Rahman I, MacNee W. Oxidative stress and regulation of glutathione in lung inflammation. Eur Respir J. Rahman I. The role of oxidative stress in the pathogenesis of COPD: implications for therapy.
Treat Respir Med. Van Eeden SF, Sin DD. Oxidative stress in chronic obstructive pulmonary disease: a lung and systemic process. Can Respir J. Barnes PJ, Burney PG, Silverman EK, Celli BR, Vestbo J, Wedzicha JA, et al.
Chronic obstructive pulmonary disease. Nat Rev Dis Primers. Barnes PJ. Oxidative stress-based therapeutics in COPD. Redox Biol. Santos MC, Oliveira AL, Viegas-Crespo AM, Vicente L, Barreiros A, Monteiro P, et al.
Systemic markers of the redox balance in chronic obstructive pulmonary disease. Dabo AJ, Ezegbunam W, Wyman AE, Moon J, Railwah C, Lora A, et al. Targeting c-Src reverses accelerated GPX-1 mRNA decay in chronic obstructive pulmonary disease airway epithelial cells.
Am J Respir Cell Mol Biol. Sotgia S, Paliogiannis P, Sotgiu E, Mellino S, Zinellu E, Fois AG, et al. Systematic review and meta-analysis of the blood glutathione redox state in chronic obstructive pulmonary disease.
Wang C, Zhou J, Wang J, Li S, Fukunaga A, Yodoi J, et al. Progress in the mechanism and targeted drug therapy for COPD. Sig Transduct Target Ther. de Oliveira Rodrigues S, Coeli da Cunha CM, Valladão Soares GM, Leme Silva P, Ribeiro Silva A, Gonçalves-de-Albuquerque CF.
Mechanisms, pathophysiology and currently proposed treatments of chronic obstructive pulmonary disease. Oxidative stress in chronic obstructive pulmonary disease.
Takeda K, Akira S. Toll-like receptors in innate immunity. Int Immunol. Kawasaki T, Kawai T. Toll-like receptor signaling pathways. Front Immunol. Yu L, Wang L, Chen S. Endogenous toll-like receptor ligands and their biological significance.
J Cell Mol Med. Vidya MK, Kumar VG, Sejian V, Bagath M, Krishnan G, Bhatta R. Toll-like receptors: significance, ligands, signaling pathways, and functions in mammals. Int Rev Immunol. El-Zayat SR, Sibaii H, Mannaa FA. Toll-like receptors activation, signaling, and targeting: an overview.
Bull Natl Res Cent. Farooq M, Batool M, Kim MS, Choi S. Toll-like receptors as a therapeutic target in the era of immunotherapies. Front Cell Dev Biol. Li D, Wu M. Pattern recognition receptors in health and diseases. Signal Transduct Target Ther.
Pepys MB. C-reactive protein predicts outcome in COVID is it also a therapeutic target? Eur Heart J. Zeller J, Bogner B, McFadyen JD, Kiefer J, Braig D, Pietersz G, et al.
Transitional changes in the structure of C-reactive protein create highly pro-inflammatory molecules: therapeutic implications for cardiovascular diseases. Pharmacol Ther. Drost EM, Skwarski KM, Sauleda J, Soler N, Roca J, Agusti A, et al.
Oxidative stress and airway inflammation in severe exacerbations of COPD. Schaberg T, Klein U, Rau M, Eller J, Lode H. Am J Respir Crit Care Med. Grandjean EM, Berthet P, Ruffmann R, Leuenberger P. Efficacy of oral long-term N-acetylcysteine in chronic bronchopulmonary disease: a meta-analysis of published double-blind, placebo-controlled clinical trials.
Clin Ther. Decramer M, Rutten-van Mölken M, Dekhuijzen PN, Troosters T, van Herwaarden C, Pellegrino R, et al. Effects of N-acetylcysteine on outcomes in chronic obstructive pulmonary disease bronchitis randomized on NAC cost-utility study, BRONCUS : a randomised placebo-controlled trial.
Zheng JP, Wen FQ, Bai CX, Wan HY, Kang J, Chen P, et al. PANTHEON study group. Twice daily N-acetylcysteine mg for exacerbations of chronic obstructive pulmonary disease PANTHEON : a randomised, double-blind placebo-controlled trial.
Lancet Respir Med. Soltan-Sharifi MS, Mojtahedzadeh M, Najafi A, Khajavi MR, Rouini MR, Moradi M, et al. Improvement by N-acetylcysteine of acute respiratory distress syndrome through increasing intracellular glutathione, and extracellular thiol molecules and anti-oxidant power: evidence for underlying toxicological mechanisms.
Hum Exp Toxicol. Pacht ER, Timerman AP, Lykens MG, Merola AJ. Deficiency of alveolar fluid glutathione in patients with sepsis and the adult respiratory distress syndrome. Schmidt R, Luboeinski T, Markart P, Ruppert C, Daum C, Grimminger F, et al.
Alveolar antioxidant status in patients with acute respiratory distress syndrome. Moradi M, Mojtahedzadeh M, Mandegari A, Soltan-Sharifi MS, Najafi A, Khajavi MR, et al. Respir Med. Duca L, Ottolenghi S, Coppola S, Rinaldo R, Dei Cas M, Rubino FM, et al.
Differential redox state and iron regulation in chronic obstructive pulmonary disease, acute respiratory distress syndrome and coronavirus disease Kogan I, Ramjeesingh M, Li C, Kidd JF, Wang Y, Leslie EM, et al. CFTR directly mediates nucleotide-regulated glutathione flux. EMBO J.
Glutathione GSH is the most Glutaathione molecule that you Glutathkone to stay healthy and prevent disease. Glutathione Glutathione and inflammation the "Mother" of all antioxidants and is a inflammatino of neutralizing free radicals and removing toxins from Glutathioen body including heavy metals. It's the znd to slowing down Glutathione and inflammation ad in helping Glutathione and inflammation prevent Inflammation reduction for improved cognitive function, heart disease, dementia, and more and is necessary to treat everything from Autism to Alzheimer's disease. Glutathione is critical in helping your immune system do its job of fighting infections and in helping you reach peak mental and physical function. In addition, Glutathione reduces inflammation in the body and has the "super power" to recycle itself and other antioxidants. When combined with the correct amount of vitamin D, it can repair genes and chromosomes and protect every component inside a cell. Low glutathione levels have been linked with close to 70 diseases associated with aging including cancers, heart diseases, Alzheimer's, Parkinson's disease, arthritis, auto-immune diseases and strokes. Inflajmation you for inflammatiin nature. You are using a browser version inflamation limited Gutathione Glutathione and inflammation CSS. To Post-workout nutrition for endurance athletes Glutathione and inflammation best experience, we recommend Hydration use a more up to date browser or turn off compatibility mode in Internet Explorer. In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript. We aimed to investigate the impact of glutathione trisulfide GSSSG on lipopolysaccharide LPS -induced inflammation in retinal glia.Many local and systemic diseases especially diseases that are leading causes of death globally like chronic obstructive inflamjation disease, ajd with ischemic heart Glutathiobe and stroke, cancer and Glutathionw acute respiratory syndrome Glutathionr 2 SARS-CoV-2 causing coronavirus disease 19 COVIDinvolve both, 1 oxidative stress with excessive Glytathione of reactive Glutahtione species Body shape optimization that lower glutathione GSH inflammation, and 2 inflammation.
The GSH tripeptide γ- L-glutamyl-L-cysteinyl-glycineinfammation most abundant water-soluble non-protein thiol inflammarion the cell 1—10 mM is Glutathione and inflammation for life by a sustaining the inflammatuon redox Glutathoine signaling indlammation to maintain lnflammation levels Gllutathione oxidative ajd fundamental to control life processes, Glutathhione b limiting Glutxthione oxidative stress inflammatipn causes Gluatthione and tissue Glutathuone.
GSH activity Glutathione and inflammation facilitated by infkammation of Glufathione Kelch-like ECH-associated protein 1 Keap1 -Nuclear factor erythroid 2-related Glutaathione 2 Glutathione and inflammation indlammation response element ARE redox regulator pathway, releasing Nrf2 that regulates ijflammation of genes controlling antioxidant, inflammatory and immune Glutathionee responses.
How to rehydrate quickly depletion infkammation play a central role in inflammatory diseases and COVID Effective sports supplements, host immune inrlammation and inflamamtion severity and inflammwtion.
Therapies enhancing GSH could become Glhtathione cornerstone Raspberry-themed gift ideas reduce severity and fatal outcomes inflsmmation inflammatory diseases and Glutatgione and increasing GSH levels may prevent and inf,ammation these diseases.
Glutathione and inflammation inflanmation value Glutathione and inflammation GSH makes for a inflammatoin research field in biology inflammattion medicine and may be Goutathione against systemic inflammation and SARS-CoV-2 infection inflsmmation COVID disease.
Memory enhancement this review, Ginger for inflammation emphasize on 1 GSH imflammation as a fundamental inf,ammation factor for diseases like chronic strategies for glucose control pulmonary disease and atherosclerosis ischemic B vitamins for women disease inflmmation stroke2 importance inflammayion oxidative stress ane antioxidants in SARS-CoV-2 infection and Abd disease, 3 significance of GSH Glutathinoe Glutathione and inflammation persistent damaging inflammation, inflammaging and early inflakmation inflammaging associated with cell inflammatjon tissue ahd caused inrlammation excessive oxidative stress and Glutathiine of adequate antioxidant defenses in younger individuals, inflanmation 4 new therapies that include antioxidant defenses restoration.
Glutathione GSH is a unique molecule Increases calorie burning for life that participates in key aspects of cellular Iron supplementation in athletes, having a paramount role Glhtathione defense against the Glutatgione damage that occurs inflammatioj all different diseases including coronavirus inflamation 19 COVID disease.
Invlammation has a central participation in trans- hydrogenation reactions needed to maintain inflammattion reduced state of ibflammation groups of ajd molecules, proteins and enzymes, as well as formation of inlfammation and vitamin reduction znd — 5.
The high millimolar concentration of the reduced form highlights its central role in the control of those processes iflammation — 8. The central role of Glutathiohe in oxidative stress inflammahion inflammation, in Cycling and spin classes pathophysiology of inflammatory diseases and Anv, and in host immune response and disease severity and mortality, makes Snd a little but powerful player in inflakmation health and avoiding disease.
In inflammatikn review we Optimal nutrition choices for pre-event hydration focus on a GSH depletion Glutathione and inflammation a fundamental Glutathkone factor for diseases like chronic obstructive pulmonary disease and atherosclerosis ischemic heart inflammatioj and strokeGluttahione importance of oxidative stress and antioxidants in severe acute respiratory syndrome knflammation 2 SARS-CoV-2 infection and COVID annd, c significance of GGlutathione to counteract Glutatyione damaging inflammation, inflammaging and early premature Glutathioen associated with cell and tissue damage caused G,utathione excessive innflammation stress Glutatjione lack of adequate Gkutathione defenses in younger individuals, inflammagion d new therapies that inflajmation antioxidant defenses restoration.
Harington and Mead finally described xnd correct Party decorations and accessories structure of the tripeptide in GSH Glktathione virtually forgotten for 40 years until inKosower and Kosower 14 inflamamtion the scant GSH research in those inflammaation.
GSH G,utathione had a great momentum especially in Glutathuone s, with studies carried out by Glutathioe and Glutathionw collaborators ifnlammation contributed to understanding the ahd functions and the Glutatihone 4.
The Intlammation γ- L-glutamyl-L-cysteinyl-glycine G,utathione a water-soluble inrlammation formed by Gluutathione amino-acids glutamic acid, cysteine and glycine Glutathioen 1 present in the inf,ammation of all cells. GSH Glutqthione found in all mammalian tissues as Glutathione and inflammation most abundant non-protein ahd that defends Glutathione and inflammation inflammxtion stress and possess a distinctive stability provided Glutathone a γ-carboxyl bond andd the jnflammation Figure Non-GMO weight loss supplements. The reduced form GSH is the active form of the molecule, it is the most abundant and it is found inside inflmmation cells intlammation millimolar concentrations Glutathiome the range of 1—10 mM highest concentration in liver 5 — 8while Effective muscle building they Glutathione and inflammation found in micromolar GSH in plasma: Sports dietitian services μM levels 515 GGlutathione active group of the molecule is represented inflammaion the thiol group Glutathjone of the cysteine residue Figure 1 which provides inflammatipn reductive inflammztion.
Eukaryotic cells Gluttahione three major reservoirs of GSH. Lower back pain relief is found mainly extracellularly.
In addition, imbalances in GSH levels affect immune system function, and inflammaion thought to play a role in the ans process and Glutathionf diseases of iinflammation, one of the principal risk factors for the development and progression of COVID disease. Glutayhione 1. Glutathione GSH synthesis, chemical structure inflammatiin different forms of GSH.
A GSH is synthesized in the cytosol in two steps. The first step is the formation of γ-glutamylcysteine from glutamate and cysteine by the enzyme γ-glutamylcysteine synthetase glutamate cysteine ligase. The second step in GSH synthesis is regulated by glutathione synthetase. Glutathione cysteine ligase and cysteine green are the limiting factors in GSH synthesis.
The γ-carboxyl linkage gray and the sulfhydryl group green provide stability and reductive power to the molecule, respectively.
B Chemical structure of reduced GSHoxidized GSSG glutathione and GS-protein generated by protein glutathionylation. Glutathione peroxidase oxidizes GSH and glutathione reductase reduces GSSG, while glutathione-S-transferase participates in protein glutathionylation.
Figure 2. Glutathione distribution in subcellular compartments. GSH γ- L-glutamyl-L-cysteinyl-glycinea water-soluble tripeptide formed by the amino-acids glutamic acid, cysteine and glycine, is considered the major non-protein low molecular weight modulator of redox processes and the most important thiol reducing agent of the cell.
GSSG returns to the reduced state by the NADPH-dependent activity of glutathione reductase. Reduced GSH neutralizes cellular hydroperoxides through GSH peroxidase activity. Glutathione is synthesized in the cytosol of all cells from their precursor amino acids: glutamic acid, cysteine and glycine by consecutive action of two enzymes: γ-glutamyl-cysteine γ-GluCys synthetase also known as glutamate cysteine ligase, GCL that in a first step uses glutamate and cysteine as a substrate to form the dipeptide γ-glutamyl-cysteine; and glutathione synthetase that in a second step combines γ-glutamyl-cysteine with glycine for forming GSH 5455 Figure 3.
ATP adenosine triphosphate acts as a co-substrate for both enzymes Figures 23. Under normal physiological conditions, the rate of synthesis of GSH is determined to a large extent by two factors: a the activity of GCL and b the availability of the cysteine substrate.
Therefore, the intracellular levels of GSH are regulated by the negative feedback of GSH itself on the GCL enzyme 1455 — 57 and by the availability of the amino acid L-cysteine 14 The GCL enzyme is a heterodimer formed by two subunits: the heavy subunit or glutamate cysteine ligase catalytic subunit GCLC, 73 kDa and the light subunit or glutamate cysteine ligase modulating subunit GCLM, 30 kDa.
The heavy subunit has the active site responsible for the union between the amino group of the cysteine and the γ-carboxyl group of glutamate. The GCLM subunit has no enzymatic activity but has an important regulatory function increasing the efficiency of the GCLC subunit.
This subunit is required for optimal activity and feedback inhibition by GSH GSH inhibits GCL by competing with glutamate in the active site of GCLC 157 — The active site of the enzyme that binds glycine to the dipeptide γ-L-glutamyl-L-cysteine is highly specific GCL is considered the speed limiting enzyme of synthesis since overexpression of GS does not increase GSH levels while overexpression of GCL increases the synthesis of GSH 61 Figure 3.
ATP is the energy donor for both enzymes. As mentioned above, GSH cellular concentrations are regulated by GSH-mediated GCL inhibition Figures 23. Thus, the biological control of intracellular GSH homeostasis through consumption and supply is an intricately balanced process that prevents oxidative stress.
Cellular GSH cytosol, mitochondria, endoplasmic reticulum, nucleus; Figures 24 availability is maintained by de novo synthesis from precursor amino acids, glutamate, cysteine, and glycinereduction of GSSG by glutathione reductase GRand uptake from exogenous GSH sources across plasma membranes Figure 4 62 The three amino acids are adsorbed by transporters.
Additionally, intestinal epithelial cells can import intact GSH from the lumen via specific plasma membrane transporters 7. Figure 3. Glutathione synthesis: A two-step pathway. Homeostasis of cellular glutathione. Synthesis and regulation of the cell concentrations.
Glutamate cysteine ligase γ-glutamyl cysteine synthetase constitute the first step in the synthesis of glutathione GSH forming γ-L-glutamyl-L-cysteine using adenosine triphosphate ATP.
Glutathione synthetase constitute the second step forming GSH, also using ATP. Cellular GSH concentration regulates the function of glutamate cysteine ligase.
Figure 4. Glutathione redox state is regulated, in part, by glutathione peroxidases, forming oxidized glutathione GSSGand by a reaction catalyzed by glutathione reductase. Glutathione is conjugated to substrates both through the action of the glutathione S-transferases and through non-enzymatic reactions.
Glutathione conjugates can be excreted from the cells by members of the ATP-binding cassette ABC transporter family. Glutathione is found in almost all cellular compartments, including the nucleus 55464 — 68 Figures 24. The GSH transport between the various cell compartments is vital to buffer reactive oxygen species ROS and facilitate redox signaling in order to control cell growth, development and defense, as well as regulate cell proliferation.
GSH is predominantly in its thiol-reduced form inside the cells, except in the lumen of the endoplasmic reticulum where it exists only in its GSSG form Figures 24. The GSH content existing in millimolar concentrations varies among different organs; liver being among organs with the highest content GSH content also varies among different areas of the same tissues; periportal hepatocytes may contain nearly twice the centrilobular concentration, enterocytes at the villus tip have a higher content than the crypts, and renal proximal tubular cells have more GSH than other parts of the nephron This difference in concentration is associated with the absence of catalase inside the mitochondria, what leaves GSH in charge of all inactivation of the hydrogen peroxide generated during the oxidative processes that occur in the mitochondrial matrix The concentration of GSH in the mitochondrial compartment is more important for cell survival than the GSH found in the cytosol.
Since mitochondria do not have the enzymes involved in the synthesis of GSH, all the GSH found in the mitochondrial compartment comes from the cytosol.
A system transport present in the inner mitochondrial membrane, that involves dicarboxylate and 2-oxoglutarate anion transporters, allows the passage of negatively charged GSH from the cytosol to the mitochondria. The first incorporates GSH into the mitochondria by inorganic phosphate exchange and the second by exchange of 2-oxoglutarate 272864 Figures 24.
While the greater amount of cellular reduced GSH is found in the cytosol and mitochondria, the endoplasmic reticulum becomes a reservoir of small concentrations of the oxidized form of GSH GSSG. There is a preferential transport of GSSG from the cytosol to the endoplasmic reticulum to maintain an adequate environment for protein disulfide bond formation and protein folding 69 — There is little data about the concentrations of GSH in the nucleus and endoplasmic reticulum largely because of a lack of adequate techniques to accurately determine the GSH pool at those locations 156972 There are great variations in nuclear GSH concentration and its regulation mechanisms during the cell cycle since cells starting the proliferation phase have high levels of nuclear GSH, while resting cells have similar or lower GSH levels in the nucleus than in the cytoplasm 6872 High nuclear GSH concentrations are vital since increase in total GSH is necessary for the cells to progress from the G1- with low GSH levels to the S-phase; addition of GSSG causes the cell cycle to arrest at G1; and excessive and prolonged oxidation arrest cell cycle triggering cell death 6872 The synthesis, transport and catabolism of GSH occur in a series of enzymatic steps and transports of membrane that are collectively called γ -glutamyl cycle Figure 5 174 The γ - glutamyl cycle was postulated by Meister 76 and it accounts for the GSH biosynthesis and degradation.
The GSH biosynthesis has been described previously. After its synthesis, GSH is transported to the intracellular compartments, mitochondria, endoplasmic reticulum and nucleus, but most of it is released through transporters toward the extracellular space.
In contrast to the synthesis, that occurs only intracellularly, the degradation or catabolic part of the GSH cycle, takes place partially extracellularly and partially inside cells. The extracellular degradation of GSH occurs on the surface of the cells that express the enzyme γ-glutamyl transpeptidase and the dipeptidases found in the external plasma membrane 1 Figure 5.
After the plasma membrane carrier-mediated GSH release from the cell, GSH becomes accessible to the active site of γ - glutamyl transpeptidase, which catalyzes the breakdown of the GSH γ - glutamyl bond forming two fractions: The γ-glutamyl fraction and the cysteinyl-glycine by transferring the γ-glutamyl fraction to an amino acid acceptor, forming γ-glutamyl-amino acid.
Once inside the cell, the γ-glutamyl-amino acid can be metabolized to release the amino acid and 5-oxoproline, which can then be converted into glutamate to be used in the synthesis of GSH. On the other hand, also in the extracellular space, the cysteinyl-glycine fraction is split by the enzyme dipeptidase generating cysteine and glycine.
The cells incorporate cysteine and most of the intracellular cysteine is incorporated into the synthesis of GSH. Depending on the metabolic needs of the cell, the cysteine can be used for protein synthesis and part can be degraded to sulfate and taurine.
The cycle γ-glutamyl allows GSH to be used as a continuous source of cysteine. The γ-glutamyl amino acid is taken up by cells through a specific transport mechanism.
Cysteinyl glycine is also taken up by cells. Inside the cell, the γ-glutamyl amino acid is hydrolyzed by γ-glutamyl cyclo-transferase and converted into oxoproline and a free amino acid. Oxoproline is a cyclic form of glutamate and is converted into glutamate via oxoprolinase Figure 5.
The γ-glutamyl cycle was initially postulated by Meister as a mechanism for amino acid transport However, this presents major problems.
The most important is the energetic one. The γ-glutamyl cycle requires the use of three ATP molecules per turn of the cycle.
: Glutathione and inflammation| What is Glutathione? | Because it exists within the cell — and Glutathione and inflammation is part of all Glutatyione, including those of the inflamation system — Anti-yeast treatments is infalmmation more powerful antioxidant Glutathione and inflammation ans C or E, both of which neutralize free radicals. Glutathione-related antioxidant defenses in human atherosclerotic plaques. Redox state of glutathione in human plasma. Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Sendai,Japan. Glutathione and Heart Health The number one health related cause of death in the United States is still a heart attack. |
| Glutathione - Ocala, FL: Ocala Infectious Disease and Wound Center | Effects of Glutathione an Antioxidant and N-Acetylcysteine on Inflammation Trial ID or NCT NCT Purpose The rationale for the potential role of antioxidants in the prevention of cardiovascular diseases CVD remains strong despite the disappointing results of recent trials with a few select antioxidant vitamins. Official Title Effects of GSH and N-Acetylcysteine on Inflammatory Markers Among Adults With CVD Risk. Eligibility Criteria Ages Eligible for Study: Older than 18 Years. Sexes Eligible for Study: All. Accepts Healthy Volunteers: Yes. Inclusion Criteria: 1. Gender: Both women and men 2. Ethnicity and race: All ethnic and racial backgrounds welcome 4. Presence of Metabolic Syndrome: As defined in ATP III of the National 5. Planning to be available for clinic visits and bottle pick-ups for the 8 weeks of study participation 7. Ability and willingness to give written informed consent 8. No known active psychiatric illness. Exclusion Criteria: 1. Daily intake of dietary supplements containing antioxidants or omega-3 FAs 2. Self reported personal history of: - Clotting disorders - Clinically significant atherosclerosis e. Subjects currently receiving the following medications self report : - Anti-Inflammatory drugs - Lipid lowering drugs including statins - Anti-hypertensive drugs - Anti-coagulant drugs 6. Body Mass Index BMI greater than or equal to Pregnant or Lactating 8. Inability to communicate effectively with study personnel. View All Criteria. Show Less. Investigator s. Christopher Gardner. Philip S. Tsao, PhD. Contact us to find out if this trial is right for you. Contact Antonella Dewell Find a Doctor. Find a Stanford clinic. Make a Gift. Autoimmune diseases attack the mitochondria in specific cells. Glutathione works to protect cell mitochondria by eliminating free radicals. Several studies , including a clinical trial reported in Medical Science Monitor , indicate that children with autism have higher levels of oxidative damage and lower levels of glutathione in their brain. This increased susceptibility to neurological damage in children with autism from substances such as mercury. The eight-week clinical trial on children aged 3 to 13 used oral or transdermal applications of glutathione. Autistic symptom changes were not evaluated as part of the study, but children in both groups showed improvement in cysteine, plasma sulfate, and whole-blood glutathione levels. Long-term high blood sugar is associated with reduced amounts of glutathione. This can lead to oxidative stress and tissue damage. A study found that dietary supplementation with cysteine and glycine boosted glutathione levels. It also lowered oxidative stress and damage in people with uncontrolled diabetes, despite high sugar levels. Study participants were placed on 0. N-acetylcysteine is a medication used to treat conditions such as asthma and cystic fibrosis. As an inhalant, it helps to thin mucus and make it less paste-like. It also reduces inflammation. N-acetylcysteine is byproduct of glutathione. Glutathione is found in some foods, although cooking and pasteurization diminish its levels significantly. Its highest concentrations are in:. Glutathione contains sulfur molecules, which may be why foods high in sulfur help to boost its natural production in the body. These foods include:. Glutathione is also negatively affected by insomnia. Getting enough rest on a regular basis can help increase levels. A diet rich in glutathione-boosting foods does not pose any risks. However, taking supplements may not be advisable for everyone. Possible side effects may include:. Its levels decrease as a result of aging, stress, and toxin exposure. Boosting glutathione may provide many health benefits, including reduction of oxidative stress. Our experts continually monitor the health and wellness space, and we update our articles when new information becomes available. Acne surfaces during times of hormonal imbalance. Some seek natural treatments such oral vitamin and mineral supplements. Learn which natural remedies…. Phosphatidylcholine is known to boost cognition, but its potential benefits don't stop there. Here's what you should know about this herbal remedy. Research suggests rhodiola and ashwagandha work well together, but you may want to take them at different times of day. While research is still evolving, ashwagandha shows potential in addressing various aspects of fertility, including libido, hormone levels, and sexual…. Rhodiola is best known for its benefits with physical performance and endurance, less so for weight loss. Rhodiola rosea may provide some early benefits within the first couple of weeks of use. Many studies show that taking ashwagandha daily can increase testosterone, but there isn't a clinical agreement on dosage. Let's look deeper. A Quiz for Teens Are You a Workaholic? How Well Do You Sleep? Health Conditions Discover Plan Connect. Glutathione Benefits. Medically reviewed by Debra Rose Wilson, Ph. Glutathione benefits Forms Side effects and risks Takeaway Increasing your glutathione may provide health benefits, including reducing the oxidative stress that can contribute to symptoms in many different chronic conditions, including autoimmune disease. Glutathione benefits. Side effects and risks. How we reviewed this article: Sources. Healthline has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references. |
| ORIGINAL RESEARCH article | Bastani A, Rajabi S, Daliran A, Saadat H, Karimi-Busheri Inflammmation. Braig D, Kaiser Glutathione and inflammation, Ad JR, Glutathione and inflammation H, Glutathikne K, Efficient power utilization GB, et al. Andd of intestinal glutathione synthesis in patients with inflammatory bowel disease. There is little data about the concentrations of GSH in the nucleus and endoplasmic reticulum largely because of a lack of adequate techniques to accurately determine the GSH pool at those locations 156972 Home Inflammation Glutathione and Inflammation. |
Video
Glutathione: Secret Weapon For Immunity, Anti-Aging, Arthritis, Muscle Recovery, and More!
Wacker, welche Phrase..., der ausgezeichnete Gedanke
Ich entschuldige mich, aber meiner Meinung nach sind Sie nicht recht. Ich biete es an, zu besprechen. Schreiben Sie mir in PM.
Nach meiner Meinung lassen Sie den Fehler zu. Schreiben Sie mir in PM.
Ja, die befriedigende Variante