Differential Responses of Methionine Sulfoxide Reductases A and B to Anoxia and Oxidative Stress in the Freshwater Turtle Trachemys scripta

Oxidative stress has been acknowledged as a major factor in aging, senescence and neurodegenerative conditions. Mammalian models are susceptible to these stresses following the restoration of oxygen after anoxia; however, some organisms including the freshwater turtle Trachemys scripta can withstand repeated anoxia and reoxygenation without apparent pathology. T. scripta thus provides us with an alternate vertebrate model to investigate physiological mechanisms of neuroprotection. The objective of this study was to investigate the antioxidant methionine sulfoxide reductase system (Msr) in turtle neuronal tissue. We examined brain transcript and protein levels of MsrA and MsrB and examined the potential for the transcription factor FOXO3a to regulate the oxygen-responsive changes in Msr in vitro. We found that Msr mRNA and protein levels are differentially upregulated during anoxia and reoxygenation, and when cells were exposed to chemical oxidative stress. However, while MsrA and MsrB3 levels increased when cell cultures were exposed to chemical oxidative stress, this induction was not enhanced by treatment with epigallocatechin gallate (EGCG), which has previously been shown to enhance FOXO3a levels in the turtle. These results suggest that FOXO3a and Msr protect the cells from oxidative stress through different molecular pathways, and that both the Msr pathway and EGCG may be therapeutic targets to treat diseases related to oxidative damage.

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Methionine sulfoxide reductase 2 reversibly regulates Mge1, a cochaperone of mitochondrial Hsp70, during oxidative stress

Molecular Biology of the Cell ◽

10.1091/mbc.e14-09-1371 ◽

2015 ◽

Vol 26 (3) ◽

pp. 406-419 ◽

Cited By ~ 17

Author(s):

Praveen Kumar Allu ◽

Adinarayana Marada ◽

Yerranna Boggula ◽

Srinivasu Karri ◽

Thanuja Krishnamoorthy ◽

...

Keyword(s):

Oxidative Stress ◽

Methionine Sulfoxide ◽

Methionine Sulfoxide Reductase ◽

Yeast Cells ◽

Nucleotide Exchange ◽

New Paradigm ◽

Methionine Sulfoxide Reductases ◽

Mitochondrial Hsp70

Peptide methionine sulfoxide reductases are conserved enzymes that reduce oxidized methionines in protein(s). Although these reductases have been implicated in several human diseases, there is a dearth of information on the identity of their physiological substrates. By using Saccharomyces cerevisiae as a model, we show that of the two methionine sulfoxide reductases (MXR1, MXR2), deletion of mitochondrial MXR2 renders yeast cells more sensitive to oxidative stress than the cytosolic MXR1. Our earlier studies showed that Mge1, an evolutionarily conserved nucleotide exchange factor of Hsp70, acts as an oxidative sensor to regulate mitochondrial Hsp70. In the present study, we show that Mxr2 regulates Mge1 by selectively reducing MetO at position 155 and restores the activity of Mge1 both in vitro and in vivo. Mge1 M155L mutant rescues the slow-growth phenotype and aggregation of proteins of mxr2Δ strain during oxidative stress. By identifying the first mitochondrial substrate for Mxrs, we add a new paradigm to the regulation of the oxidative stress response pathway.

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An unusual thioredoxin system in the facultative parasite Acanthamoeba castellanii

Cellular and Molecular Life Sciences ◽

10.1007/s00018-021-03786-x ◽

2021 ◽

Vol 78 (7) ◽

pp. 3673-3689

Author(s):

David Leitsch ◽

Alvie Loufouma Mbouaka ◽

Martina Köhsler ◽

Norbert Müller ◽

Julia Walochnik

Keyword(s):

Oxidative Stress ◽

Stop Codon ◽

Acanthamoeba Castellanii ◽

Methionine Sulfoxide ◽

Redox System ◽

Methionine Sulfoxide Reductase ◽

Methionine Sulfoxide Reductase A ◽

Protein Levels ◽

Thioredoxin System ◽

Facultative Parasite

AbstractThe free-living amoeba Acanthamoeba castellanii occurs worldwide in soil and water and feeds on bacteria and other microorganisms. It is, however, also a facultative parasite and can cause serious infections in humans. The annotated genome of A. castellanii (strain Neff) suggests the presence of two different thioredoxin reductases (TrxR), of which one is of the small bacterial type and the other of the large vertebrate type. This combination is highly unusual. Similar to vertebrate TrxRases, the gene coding for the large TrxR in A. castellanii contains a UGA stop codon at the C-terminal active site, suggesting the presence of selenocysteine. We characterized the thioredoxin system in A. castellanii in conjunction with glutathione reductase (GR), to obtain a more complete understanding of the redox system in A. castellanii and the roles of its components in the response to oxidative stress. Both TrxRases localize to the cytoplasm, whereas GR localizes to the cytoplasm and the large organelle fraction. We could only identify one thioredoxin (Trx-1) to be indeed reduced by one of the TrxRases, i.e., by the small TrxR. This thioredoxin, in turn, could reduce one of the two peroxiredoxins tested and also methionine sulfoxide reductase A (MsrA). Upon exposure to hydrogen peroxide and diamide, only the small TrxR was upregulated in expression at the mRNA and protein levels, but not the large TrxR. Our results show that the small TrxR is involved in the A. castellanii’s response to oxidative stress. The role of the large TrxR, however, remains elusive.

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The Oxidized Protein Repair Enzymes Methionine Sulfoxide Reductases and Their Roles in Protecting against Oxidative Stress, in Ageing and in Regulating Protein Function

Antioxidants ◽

10.3390/antiox7120191 ◽

2018 ◽

Vol 7 (12) ◽

pp. 191 ◽

Cited By ~ 9

Author(s):

Sofia Lourenço dos Santos ◽

Isabelle Petropoulos ◽

Bertrand Friguet

Keyword(s):

Oxidative Stress ◽

Reactive Oxygen Species ◽

Protein Function ◽

Methionine Sulfoxide ◽

Methionine Sulfoxide Reductase ◽

Methionine Oxidation ◽

Oxygen Species ◽

Sulfenic Acid ◽

Protein Repair ◽

Methionine Sulfoxide Reductases

Cysteine and methionine residues are the amino acids most sensitive to oxidation by reactive oxygen species. However, in contrast to other amino acids, certain cysteine and methionine oxidation products can be reduced within proteins by dedicated enzymatic repair systems. Oxidation of cysteine first results in either the formation of a disulfide bridge or a sulfenic acid. Sulfenic acid can be converted to disulfide or sulfenamide or further oxidized to sulfinic acid. Disulfide can be easily reversed by different enzymatic systems such as the thioredoxin/thioredoxin reductase and the glutaredoxin/glutathione/glutathione reductase systems. Methionine side chains can also be oxidized by reactive oxygen species. Methionine oxidation, by the addition of an extra oxygen atom, leads to the generation of methionine sulfoxide. Enzymatically catalyzed reduction of methionine sulfoxide is achieved by either methionine sulfoxide reductase A or methionine sulfoxide reductase B, also referred as to the methionine sulfoxide reductases system. This oxidized protein repair system is further described in this review article in terms of its discovery and biologically relevant characteristics, and its important physiological roles in protecting against oxidative stress, in ageing and in regulating protein function.

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L-Methionine Protects against Oxidative Stress and Mitochondrial Dysfunction in an In Vitro Model of Parkinson’s Disease

Antioxidants ◽

10.3390/antiox10091467 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1467

Author(s):

Mariano Catanesi ◽

Laura Brandolini ◽

Michele d’Angelo ◽

Elisabetta Benedetti ◽

Maria Grazia Tupone ◽

...

Keyword(s):

Oxidative Stress ◽

Parkinson’S Disease ◽

Parkinson's Disease ◽

Amino Acid ◽

Mitochondrial Dysfunction ◽

In Vitro Model ◽

Methionine Sulfoxide ◽

Methionine Sulfoxide Reductase ◽

Vitro Model

Methionine is an aliphatic, sulfur-containing, essential amino acid that has been demonstrated to have crucial roles in metabolism, innate immunity, and activation of endogenous antioxidant enzymes, including methionine sulfoxide reductase A/B and the biosynthesis of glutathione to counteract oxidative stress. Still, methionine restriction avoids altered methionine/transmethylation metabolism, thus reducing DNA damage and possibly avoiding neurodegenerative processes. In this study, we wanted to study the preventive effects of methionine in counteracting 6-hydroxydopamine (6-OHDA)-induced injury. In particular, we analyzed the protective effects of the amino acid L-methionine in an in vitro model of Parkinson’s disease and dissected the underlying mechanisms compared to the known antioxidant taurine to gain insights into the potential of methionine treatment in slowing the progression of the disease by maintaining mitochondrial functionality. In addition, to ascribe the effects of methionine on mitochondria and oxidative stress, methionine sulfoxide was used in place of methionine. The data obtained suggested that an L-methionine-enriched diet could be beneficial during aging to protect neurons from oxidative imbalance and mitochondrial dysfunction, thus preventing the progression of neurodegenerative processes.

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Oxidative Stress Mediates the Fetal Programming of Hypertension by Glucocorticoids

Antioxidants ◽

10.3390/antiox10040531 ◽

2021 ◽

Vol 10 (4) ◽

pp. 531

Author(s):

Jeremy Lamothe ◽

Sandhya Khurana ◽

Sujeenthar Tharmalingam ◽

Chad Williamson ◽

Collin J. Byrne ◽

...

Keyword(s):

Oxidative Stress ◽

Blood Pressure ◽

Superoxide Dismutase ◽

Fetal Programming ◽

Cardiovascular Health ◽

Phenylalanine Hydroxylase ◽

Epigallocatechin Gallate ◽

Female Offspring ◽

Glutathione Peroxidase 1 ◽

Protein Levels

The field of cardiovascular fetal programming has emphasized the importance of the uterine environment on postnatal cardiovascular health. Studies have linked increased fetal glucocorticoid exposure, either from exogenous sources (such as dexamethasone (Dex) injections), or from maternal stress, to the development of adult cardiovascular pathologies. Although the mechanisms are not fully understood, alterations in gene expression driven by altered oxidative stress and epigenetic pathways are implicated in glucocorticoid-mediated cardiovascular programming. Antioxidants, such as the naturally occurring polyphenol epigallocatechin gallate (EGCG), or the superoxide dismutase (SOD) 4-hydroxy-TEMPO (TEMPOL), have shown promise in the prevention of cardiovascular dysfunction and programming. This study investigated maternal antioxidant administration with EGCG or TEMPOL and their ability to attenuate the fetal programming of hypertension via Dex injections in WKY rats. Results from this study indicate that, while Dex-programming increased blood pressure in male and female adult offspring, administration of EGCG or TEMPOL via maternal drinking water attenuated Dex-programmed increases in blood pressure, as well as changes in adrenal mRNA and protein levels of catecholamine biosynthetic enzymes phenylalanine hydroxylase (PAH), tyrosine hydroxylase (TH), dopamine beta hydroxylase (DBH), and phenylethanolamine N-methyltransferase (PNMT), in a sex-specific manner. Furthermore, programmed male offspring displayed reduced antioxidant glutathione peroxidase 1 (Gpx1) expression, increased superoxide dismutase 1 (SOD1) and catalase (CAT) expression, and increased pro-oxidant NADPH oxidase activator 1 (Noxa1) expression in the adrenal glands. In addition, prenatal Dex exposure alters expression of epigenetic regulators histone deacetylase (HDAC) 1, 5, 6, 7, 11, in male and HDAC7 in female offspring. These results suggest that glucocorticoids may mediate the fetal programming of hypertension via alteration of epigenetic machinery and oxidative stress pathways.

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The Role of Prophage for Genome Diversification within a Clonal Lineage of Lactobacillus johnsonii: Characterization of the Defective Prophage LJ771

Journal of Bacteriology ◽

10.1128/jb.01802-07 ◽

2008 ◽

Vol 190 (17) ◽

pp. 5806-5813 ◽

Cited By ~ 16

Author(s):

Emmanuel Denou ◽

Raymond David Pridmore ◽

Marco Ventura ◽

Anne-Cécile Pittet ◽

Marie-Camille Zwahlen ◽

...

Keyword(s):

Methionine Sulfoxide ◽

Gene Cassette ◽

Methionine Sulfoxide Reductase ◽

Toxin Gene ◽

Clonal Lineage ◽

Lactobacillus Johnsonii ◽

Reductase Gene ◽

Phage Dna

ABSTRACT Two independent isolates of the gut commensal Lactobacillus johnsonii were sequenced. These isolates belonged to the same clonal lineage and differed mainly by a 40.8-kb prophage, LJ771, belonging to the Sfi11 phage lineage. LJ771 shares close DNA sequence identity with Lactobacillus gasseri prophages. LJ771 coexists as an integrated prophage and excised circular phage DNA, but phage DNA packaged into extracellular phage particles was not detected. Between the phage lysin gene and attR a likely mazE (“antitoxin”)/pemK (“toxin”) gene cassette was detected in LJ771 but not in the L. gasseri prophages. Expressed pemK could be cloned in Escherichia coli only together with the mazE gene. LJ771 was shown to be highly stable and could be cured only by coexpression of mazE from a plasmid. The prophage was integrated into the methionine sulfoxide reductase gene (msrA) and complemented the 5′ end of this gene, creating a protein with a slightly altered N-terminal sequence. The two L. johnsonii strains had identical in vitro growth and in vivo gut persistence phenotypes. Also, in an isogenic background, the presence of the prophage resulted in no growth disadvantage.

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The Role of the FOXO1/β2-AR/p-NF-κB p65 Pathway in the Development of Endometrial Stromal Cells in Pregnant Mice under Restraint Stress

International Journal of Molecular Sciences ◽

10.3390/ijms22031478 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1478

Author(s):

Jiayin Lu ◽

Yaoxing Chen ◽

Zixu Wang ◽

Jing Cao ◽

Yulan Dong

Keyword(s):

Oxidative Stress ◽

Stromal Cells ◽

Restraint Stress ◽

Target Genes ◽

Mrna Levels ◽

Endometrial Stromal Cells ◽

Protein Levels ◽

Pregnant Mice

Restraint stress causes various maternal diseases during pregnancy. β2-Adrenergic receptor (β2-AR) and Forkhead transcription factor class O 1 (FOXO1) are critical factors not only in stress, but also in reproduction. However, the role of FOXO1 in restraint stress, causing changes in the β2-AR pathway in pregnant mice, has been unclear. The aim of this research was to investigate the β2-AR pathway of restraint stress and its impact on the oxidative stress of the maternal uterus. In the study, maternal mice were treated with restraint stress by being restrained in a transparent and ventilated device before sacrifice on Pregnancy Day 5 (P5), Pregnancy Day 10 (P10), Pregnancy Day 15 (P15), and Pregnancy Day 20 (P20) as well as on Non-Pregnancy Day 5 (NP5). Restraint stress augmented blood corticosterone (CORT), norepinephrine (NE), and blood glucose levels, while oestradiol (E2) levels decreased. Moreover, restraint stress increased the mRNA levels of the FOXO family, β2-AR, and even the protein levels of FOXO1 and β2-AR in the uterus and ovaries. Furthermore, restraint stress increased uterine oxidative stress level. In vitro, the protein levels of FOXO1 were also obviously increased when β2-AR was activated in endometrial stromal cells (ESCs). In addition, phosphorylated-nuclear factor kappa-B p65 (p-NF-κB p65) and its target genes decreased significantly when FOXO1 was inhibited. Overall, it can be said that the β2-AR/FOXO1/p-NF-κB p65 pathway was activated when pregnant mice were under restraint stress. This study provides a scientific basis for the origin of psychological stress in pregnant women.

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Mn Inhibits GSH Synthesis via Downregulation of Neuronal EAAC1 and Astrocytic xCT to Cause Oxidative Damage in the Striatum of Mice

Oxidative Medicine and Cellular Longevity ◽

10.1155/2018/4235695 ◽

2018 ◽

Vol 2018 ◽

pp. 1-15 ◽

Cited By ~ 7

Author(s):

Xinxin Yang ◽

Haibo Yang ◽

Fengdi Wu ◽

Zhipeng Qi ◽

Jiashuo Li ◽

...

Keyword(s):

Oxidative Stress ◽

Oxidative Damage ◽

Dependent Manner ◽

Protein Levels ◽

Key Factor ◽

Protein Sulfhydryl ◽

Mrna And Protein Expression ◽

The Brain

Excessive manganese (Mn) can accumulate in the striatum of the brain following overexposure. Oxidative stress is a well-recognized mechanism in Mn-induced neurotoxicity. It has been proven that glutathione (GSH) depletion is a key factor in oxidative damage during Mn exposure. However, no study has focused on the dysfunction of GSH synthesis-induced oxidative stress in the brain during Mn exposure. The objective of the present study was to explore the mechanism of Mn disruption of GSH synthesis via EAAC1 and xCT in vitro and in vivo. Primary neurons and astrocytes were cultured and treated with different doses of Mn to observe the state of cells and levels of GSH and reactive oxygen species (ROS) and measure mRNA and protein expression of EAAC1 and xCT. Mice were randomly divided into seven groups, which received saline, 12.5, 25, and 50 mg/kg MnCl2, 500 mg/kg AAH (EAAC1 inhibitor) + 50 mg/kg MnCl2, 75 mg/kg SSZ (xCT inhibitor) + 50 mg/kg MnCl2, and 100 mg/kg NAC (GSH rescuer) + 50 mg/kg MnCl2 once daily for two weeks. Then, levels of EAAC1, xCT, ROS, GSH, malondialdehyde (MDA), protein sulfhydryl, carbonyl, 8-hydroxy-2-deoxyguanosine (8-OHdG), and morphological and ultrastructural features in the striatum of mice were measured. Mn reduced protein levels, mRNA expression, and immunofluorescence intensity of EAAC1 and xCT. Mn also decreased the level of GSH, sulfhydryl, and increased ROS, MDA, 8-OHdG, and carbonyl in a dose-dependent manner. Injury-related pathological and ultrastructure changes in the striatum of mice were significantly present. In conclusion, excessive exposure to Mn disrupts GSH synthesis through inhibition of EAAC1 and xCT to trigger oxidative damage in the striatum.

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Staphylococcus aureus peptide methionine sulfoxide reductases protect from human whole blood killing.

Infection and Immunity ◽

10.1128/iai.00146-21 ◽

2021 ◽

Author(s):

William N. Beavers ◽

Ashley L. DuMont ◽

Andrew J. Monteith ◽

K. Nichole Maloney ◽

Keri A. Tallman ◽

...

Keyword(s):

Oxidative Stress ◽

Staphylococcus Aureus ◽

Protein Oxidation ◽

Whole Blood ◽

Methionine Sulfoxide ◽

Methionine Sulfoxide Reductase ◽

Human Whole Blood ◽

Infection Models ◽

Intraperitoneal Infection ◽

Peptide Methionine Sulfoxide Reductase

The generation of oxidative stress is a host strategy used to control Staphylococcus aureus infections. Sulfur containing amino acids, cysteine and methionine, are particularly susceptible to oxidation because of the inherent reactivity of sulfur. Due to the constant threat of protein oxidation, many systems evolved to protect S. aureus from protein oxidation or to repair protein oxidation after it occurs. The S. aureus peptide methionine sulfoxide reductase (Msr) system reduces methionine sulfoxide to methionine. Staphylococci have four Msr enzymes, which all perform this reaction. Deleting all four msr genes in USA300 LAC (Δmsr) sensitizes S. aureus to hypochlorous acid (HOCl) killing, however, Δmsr does not exhibit increased sensitivity to H2O2 stress or superoxide anion stress generated by paraquat or pyocyanin. Consistent with increased susceptibility to HOCl killing, Δmsr is slower to recover following co-culture with both murine and human neutrophils than USA300 wildtype. Δmsr is attenuated for dissemination to the spleen following murine intraperitoneal infection and exhibits reduced bacterial burdens in a murine skin infection model. Notably, no differences in bacterial burdens were observed in any organ following murine intravenous infection. Consistent with these observations, USA300 wildtype and Δmsr have similar survival phenotypes when incubated with murine whole blood. However, Δmsr is killed more efficiently by human whole blood. These findings indicate that species-specific immune cell composition of the blood may influence the importance of Msr enzymes during S. aureus infection of the human host. IMPORTANCE Oxidative stress is a host defense strategy to control bacterial infections, and bacteria have evolved systems to counteract this innate immune defense. Here we investigate the peptide methionine sulfoxide reductase system in Staphylococcus aureus that repairs oxidized methionine residues in proteins, preventing the need to resynthesize damaged proteins de novo. Most organisms have an Msr system, and in S. aureus these enzymes are protective against HOCl killing, the major oxidant produced by neutrophils. The S. aureus Msr system does not have a significant contribution to pathogenesis in bacteremia murine infection models but does protect S. aureus in both skin and intraperitoneal infection models. Strains lacking Msr activity are killed equivalently to wildtype by murine whole blood, and Δmsr is more sensitive to killing by human whole blood than the wildtype strain. These data identify the Msr enzymes as important and potentially specific factors for S. aureus pathogenesis in the human host.

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Combination of Epigallocatechin Gallate and Sulforaphane Counteracts In Vitro Oxidative Stress and Delays Stemness Loss of Amniotic Fluid Stem Cells

Oxidative Medicine and Cellular Longevity ◽

10.1155/2018/5263985 ◽

2018 ◽

Vol 2018 ◽

pp. 1-13 ◽

Cited By ~ 10

Author(s):

Pasquale Marrazzo ◽

Cristina Angeloni ◽

Michela Freschi ◽

Antonello Lorenzini ◽

Cecilia Prata ◽

...

Keyword(s):

Oxidative Stress ◽

Stem Cells ◽

Stem Cell ◽

Amniotic Fluid ◽

Osteogenic Differentiation ◽

Epigallocatechin Gallate ◽

The Body ◽

Gene Markers ◽

Amniotic Fluid Stem Cells

Amniotic fluid stem cells (AFSCs) are characterized in vivo by a unique niche guarantying their homeostatic role in the body. Maintaining the functionality of stem cells ex vivo for clinical applications requires a continuous improvement of cell culture conditions. Cellular redox status plays an important role in stem cell biology as long as reactive oxygen species (ROS) concentration is finely regulated and their adverse effects are excluded. The aim of this study was to investigate the protective effect of two antioxidants, sulforaphane (SF) and epigallocatechin gallate (EGCG), against in vitro oxidative stress due to hyperoxia and freeze-thawing cycles in AFSCs. Human AFSCs were isolated and characterized from healthy subjects. Assays of metabolic function and antioxidant activity were performed to investigate the effect of SF and EGCG cotreatment on AFSCs. Real-time PCR was used to investigate the effect of the cotreatment on pluripotency, senescence, osteogenic and adipogenic markers, and antioxidant enzymes. Alkaline phosphatase assays and Alizarin Red staining were used to confirm osteogenic differentiation. The cotreatment with SF and EGCG was effective in reducing ROS production, increasing GSH levels, and enhancing the endogenous antioxidant defences through the upregulation of glutathione reductase, NAD(P)H:quinone oxidoreductase-1, and thioredoxin reductase. Intriguingly, the cotreatment sustained the stemness state by upregulating pluripotency markers such as OCT4 and NANOG. Moreover, the cotreatment influenced senescence-associated gene markers in respect to untreated cells. The cotreatment upregulated osteogenic gene markers and promoted osteogenic differentiation in vitro. SF and EGCG can be used in combination in AFSC culture as a strategy to preserve stem cell functionality.

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