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Background: Severe burn injury initiates a feedback cycle of inflammation, fibrosis, oxidative stress and cardiac mitochondrial damage via the PDE5A-cGMP-PKG pathway. Aim: To test if the PDE5A-cGMP-PKG pathway may contribute to burn-induced heart dysfunction. Methods: Sprague-Dawley rats were divided four groups: sham; sham/sildenafil; 24 h post burn (60% total body surface area scald burn, harvested at 24 h post burn); and 24 h post burn/sildenafil. We monitored heart function and oxidative adducts, as well as cardiac inflammatory, cardiac fibrosis and cardiac remodeling responses in vivo. Results: Sildenafil inhibited the burn-induced PDE5A mRNA level and increased the cGMP level and PKG activity, leading to the normalization of PKG down-regulated genes (IRAG, PLB, RGS2, RhoA and MYTP), a decreased ROS level (H 2 O 2 ), decreased oxidatively modified adducts (malonyldialdehyde [MDA], carbonyls), attenuated fibrogenesis as well as fibrosis gene expression (ANP, BNP, COL1A2, COL3A2, αSMA and αsk-Actin), and reduced inflammation and related gene expression (RELA, IL-18 and TGF-β) after the burn. Additionally, sildenafil treatment preserved left ventricular heart function (CO, EF, SV, LVvol at systolic, LVPW at diastolic and FS) and recovered the oxidant/antioxidant balance (total antioxidant, total SOD activity and Cu,ZnSOD activity). Conclusions: The PDE5A-cGMP-PKG pathway mediates burn-induced heart dysfunction. Sildenafil treatment recovers burn-induced cardiac dysfunction.

Background: Mental stress (MS) is related to endothelial dysfunction in overweight/obese men. It is believed that the pro-oxidant profile, associated with an imbalance in the vascular remodeling process, may contribute to deleterious effects of MS on endothelial function. However, it is unknown whether administration of ascorbic acid (AA), a potent antioxidant, can prevent oxidative and remodeling dysfunction during MS in these subjects., Methods: Fourteen overweight/obese grade I men (27 ± 7 years; 29.7 ± 2.6 kg·m -2 ) underwent the Stroop Color Word Test for 5 min to induce MS after AA (3 g) or placebo (PL, 0.9% NaCl) intravenous infusions. Venous blood samples were collected at baseline and the last minute of MS to measure nitrite concentration (chemiluminescence), protein carbonylation, thiobarbituric acid reactive substances (TBARS) and catalase activity (colorimetric assays), superoxide dismutase (SOD; immunoenzymatic assay), activities of active/inactive (pro) forms of metalloproteinases-9 and -2 (MMP; zymography) and its respective tissue inhibitors concentration (TIMP-1 and TIMP-2; immunoenzymatic assays)., Results: At baseline, MMP-9 activity (p < 0.01), the MMP-9/proMMP-9 ratio (p = 0.02) and TIMP-1 concentration (p = 0.05) were reduced, whereas proMPP-9 activity was increased (p = 0.02) after AA compared to PL infusion. After PL infusion, MS increased protein carbonylation (p < 0.01), catalase (p < 0.01), and the MMP-9/proMMP-9 ratio (p = 0.04) when compared to baseline. AA infusion reduced protein carbonylation (p = 0.02), MMP-9 activity (p < 0.01), and MMP-9/pro-MMP-9 ratio (p < 0.01), while SOD (p = 0.04 vs baseline), proMPP-9 (p < 0.01 vs PL), MMP-2 (p < 0.01 vs PL) and TIMP-2 (p = 0.02 vs baseline) remained elevated during MS., Conclusions: AA appears to minimize the oxidative imbalance and vascular remodeling induced by MS., Competing Interests: Declaration of competing interest There is no conflict of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Multiple sclerosis (MS) is a devastating autoimmune disorder characterized by oligodendrocytes (OLGs) loss and demyelination. In this study, we have examined the effects of metformin (MET) on the oligodendrogenesis, redox signaling, apoptosis, and glial responses during a self-repairing period (1-week) in the animal model of MS., Methods: For induction of demyelination, C57BL/6 J mice were fed a 0.2% cuprizone (CPZ) for 5 weeks. Thereafter, CPZ was removed for 1-week and molecular and behavioral changes were monitored in the presence or absence of MET (50 mg/kg body weight/day)., Results: MET remarkably increased the localization of precursor OLGs (NG2 + /O4 + cells) and subsequently the renewal of mature OLGs (MOG + cells) in the corpus callosum via AMPK/mammalian target of rapamycin (mTOR) pathway. Moreover, we observed a significant elevation in the antioxidant responses, especially in mature OLGs (MOG + /nuclear factor erythroid 2-related factor 2 (Nrf2 + ) cells) after MET intervention. MET also reduced brain apoptosis markers and lessened motor dysfunction in the open-field test. While MET was unable to decrease active astrogliosis (GFAP mRNA), it reduced microgliosis by down-regulation of Mac-3 mRNA a marker of pro-inflammatory microglia/macrophages. Molecular modeling studies, likewise, confirmed that MET exerts its effects via direct interaction with AMPK., Conclusions: Altogether, our study reveals that MET effectively induces lesion reduction and elevated molecular processes that support myelin recovery via direct activation of AMPK and indirect regulation of AMPK/Nrf2/mTOR pathway in OLGs. These findings facilitate the development of new therapeutic strategies based on AMPK activation for MS in the near future.

Pulmonary emphysema is a major manifestation of chronic obstructive pulmonary disease and is associated with chronic pulmonary inflammation caused by cigarette smoking, with contributions from immune cells such as neutrophils, macrophages, and lymphocytes. Although matrix metalloproteinases are well known to contribute to emphysema progression, the role of a disintegrin and metalloproteinase (ADAM) family proteins, other major metalloproteinases, in disease pathogenesis is largely unknown. ADAM17 is a major sheddase that cleaves various cell surface proteins, including CD62L, an adhesion molecule that plays a critical role in promoting the migration of immune cells to the site of inflammation. In the present study, we aimed to investigate the potential role of ADAM17 and CD62L in the development of elastase-induced emphysema. Control and Adam17 flox/flox /Mx1-Cre ( Adam17 ΔMx1 ) mice (8-10 wk old) were intratracheally injected with 5 units of porcine pancreas elastase and monitored for 35 days after injection. Lung alveolar destruction was evaluated by analyzing the mean linear intercepts of lung tissue specimens and by histopathological examination. Mean linear intercepts data indicated that the degree of elastase-induced emphysema was significantly more severe in Adam17 ΔMx1 mice. Furthermore, flow cytometry showed that CD62L + neutrophil, CD62L + macrophage, and CD62L + B lymphocyte numbers were significantly increased in Adam17 ΔMx1 mice. Moreover, the pharmacological depletion of CD62L + cells with a CD62L-neutralizing antibody ameliorated the extent of emphysema in Adam17 ΔMx1 mice. Collectively, these results suggest that ADAM17 possibly suppresses the progression of emphysema by proteolytically processing CD62L in immune cells and that ADAM17 and CD62L could be novel therapeutic targets for treating pulmonary emphysema.

Aim of the present study was to evaluate the potential beneficial and/or adverse effects of Capsicum annuum L. (cv. Fiesta) extracts at two stage of ripening (immature and mature), and at two dosages (low and high) by evaluation of biochemical profile and oxidative status in CD-1 mice. The extracts were daily administered to mice by oral gavage for 20 days. At the end of the trial, the animals were euthanatized and blood was collected. Evidence of liver damage (increase of AST, ALT and bilirubin) in the group receiving the higher dosage of immature peppers extract were observed. Even if no adverse effects were seen at the lower doses, also no signs of beneficial effects in term of health status, biochemical profile and oxidative status were detected. These results are in contrast with in vitro findings and raise doubts about the possible use of Capsicum annuum L. (cv. Fiesta) as a nutritional supplement.

Reactive oxygen and nitrogen species have been implicated in many biological processes and diseases, including immune responses, cardiovascular dysfunction, neurodegeneration, and cancer. These chemical species are short-lived in biological settings, and detecting them in these conditions and diseases requires the use of molecular probes that form stable, easily detectable, products. The chemical mechanisms and limitations of many of the currently used probes are not well-understood, hampering their effective applications. Boronates have emerged as a class of probes for the detection of nucleophilic two-electron oxidants. Here, we report the results of an oxygen-18-labeling MS study to identify the origin of oxygen atoms in the oxidation products of phenylboronate targeted to mitochondria. We demonstrate that boronate oxidation by hydrogen peroxide, peroxymonocarbonate, hypochlorite, or peroxynitrite involves the incorporation of oxygen atoms from these oxidants. We therefore conclude that boronates can be used as probes to track isotopically labeled oxidants. This suggests that the detection of specific products formed from these redox probes could enable precise identification of oxidants formed in biological systems. We discuss the implications of these results for understanding the mechanism of conversion of the boronate-based redox probes to oxidant-specific products., (© 2020 Rios et al.)

Implications of the role of antioxidant buffering in reactive oxygen species (ROS)-antioxidant interactions and associated redox regulation during adventitious root formation (ARF) were assessed in redox-manipulated salicylic acid (SA)-treated hypocotyl explants of mung bean [Vigna radiata (L.) R. Wilczek]. Application of pro-oxidant H 2 O 2 (500 μM) followed by SA (600 μM) was shown to stimulate ARF, whereas treatments combining 600 μM SA and 10 × 10 -4 M DPI (diphenyleneiodonium, an inhibitor of NADPH-oxidase) and 600 μM and SA 10 × 10 -4 M (dimethylthiourea, a free radical scavenger) were found to prevent ARF. The redox status of the experimental explants monitored under such treatment conditions (in terms of accumulation of pro-oxidants, in situ localization of O 2 - and H 2 O 2 , radical scavenging property and total thiol content) revealed significant changes in ROS-antioxidant interactions at the metabolic interface, causing alterations in the pattern of ARF. Further, the assessment of activities and transcript abundance of the enzymes of the H 2 O 2 turnover pathway (mainly the ascorbate-glutathione system) supported the transcriptional regulation of genes such as vrrboh, vrAPX, vrGR, vrSOD, and vrCAT and the activities of the relevant enzymes necessary for the generation of endogenous redox cues during ARF. The present work provides an inventory in support of the importance of antioxidant buffering associated with redox regulation for the origin of the metabolic redox cue (redox signal) necessary for SA-induced ARF in mung bean., Competing Interests: Declaration of Competing Interest The authors declare that they has no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier GmbH. All rights reserved.)

Cisplatin is an effective anticancer used widely in treatment of solid and germ cell tumors, however, the immense toxicity on healthy tissues discourages cisplatin use in prolonged treatment protocols. Testicular toxicity is amongst its undesired adverse effects. Nilotinib is a second generation multityrosine kinase inhibitor which is used as an anticancer agent with anti-inflammatory and antioxidant activities. In the present study, a single dose of cisplatin (7 mg/kg, I.P) to rats induced a significant testicular injury. Daily administration of nilotinib (20 mg/kg, orally) 24 h post cisplatin injection for 10 days ameliorated testicular damage. Nilotinib significantly increased serum testosterone and sperm concentration outside frame of oligospermia with simultaneous full recovery of sperm viability. Nevertheless, biomarkers of apoptosis such as JNKs and Caspase -3, were significantly reduced. Moreover, improved antioxidant status of the testes was inferred by significant elevation of GSR, SOD and TAC alongside with reduction in lipid peroxidation biomarkers; MDA and 4-HNE. Flow Cytometry analysis of the cell cycle confirmed a significant increase in the percentage of testicular cells present in G2/M phase and a significant decrease in the percentage of apoptotic testicular cells after nilotinib administration. Histopathologically, nilotinib preserved testicular architecture showing significant numbers of sperm and spermatids within lumens of seminiferous tubule. Furthermore, nilotinib enhanced testicular expression of Ki67 significantly, providing evidence of testicular regeneration. In conclusion, nilotinib refinement of cisplatin induced testicular toxicity is attributed to enhancing antioxidant capabilities, decreasing apoptotic signals and restoring regenerative capacity of testes suggesting nilotinib to be used in conjunction with cisplatin in treatment protocols to avoid cisplatin induced long term testicular toxicity., Competing Interests: Declaration of Competing Interest Authors declare no conflict of interest, (Copyright © 2020 Elsevier B.V. All rights reserved.)

Oxidative stress (OS) is detrimental to sperm functions, and the oxidation reduction potential (ORP) is a good measure of OS as it considers the balance between oxidants and reductants. Total motile sperm count (TMSC) is viewed as the single most important semen analysis parameter that can predict male infertility severity, and its correlation with ORP has never been undertaken. The objectives of this study were to assess the correlation between ORP and TMSC, to identify the ORP cutoff value based on the TMSC result, and to compare this cutoff value with previously reported ORP cutoff values in literature. One thousand one hundred and sixty-eight infertile patients and 100 fertile controls were enrolled. Demographic and semen data of the participants were retrieved and analyzed. Wilcoxon's rank-sum test compared variables between infertile men and fertile controls; Spearman's correlation assessed the static ORP (sORP)-TMSC relationship for the whole sample and among each group individually. Using a 20×10 6 TMSC threshold, receiver operator characteristic (ROC) analysis determined the sORP cutoff associated with the highest predictive values. TMSC was significantly negatively correlated with sORP across all participants (r = 0.86, P < 0.001), among infertile patients (r = 0.729, P < 0.001), and among fertile controls (r = 0.53, P < 0.001). A 20-million TMSC threshold determined an sORP cutoff value of 2.34 mV/10 6 sperm/ml to be associated with 82.9% sensitivity, 82.8% specificity, 91.5% positive predictive value (PPV), 68.5% negative predictive value (NPV), and 82.9% overall accuracy. Compared with previously reported cutoff values in searched literature, the 2.34 mV/10 6 sperm/ml cutoff value identified in our study yielded the highest overall diagnostic accuracy in the evaluation of infertile men., Competing Interests: None

Free radicals are chemical species (atoms, molecules, or ions) containing one or more unpaired electrons in their external orbitals and generally display a remarkable reactivity. The evidence of their existence was obtained only at the beginning of the 20th century. Chemists gradually ascertained the involvement of free radicals in organic reactions and, in the middle of the 20th century, their production in biological systems. For several decades, free radicals were thought to cause exclusively damaging effects . This idea was mainly supported by the finding that oxygen free radicals readily react with all biological macromolecules inducing their oxidative modification and loss of function. Moreover, evidence was obtained that when, in the living organism, free radicals are not neutralized by systems of biochemical defences, many pathological conditions develop. However, after some time, it became clear that the living systems not only had adapted to the coexistence with free radicals but also developed methods to turn these toxic substances to their advantage by using them in critical physiological processes. Therefore, free radicals play a dual role in living systems: they are toxic by-products of aerobic metabolism, causing oxidative damage and tissue dysfunction, and serve as molecular signals activating beneficial stress responses. This discovery also changed the way we consider antioxidants. Their use is usually regarded as helpful to counteract the damaging effects of free radicals but sometimes is harmful as it can block adaptive responses induced by low levels of radicals., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 Sergio Di Meo and Paola Venditti.)

Ethnopharmacological Relevance: Seahorses (Hippocampus erectus), belonging to syngnathidae of syngnathiformes, are a traditional Chinese medicine for increasing and balancing vital energy within the body and brain, as well as calming mood and improving sleep., Aim of the Study: Based on the hypothesis of monoamine neurotransmitter deficiency, current antidepressant treatments, with many side effects, are ineffective. Thus, novel hypotheses, inflammation, oxidative stress and neurotrophin dysfunction were proposed. Since seahorses can modulate immune function, reduce oxidants and nourish brain function, it may effectively treat depression. Therefore, this study aimed to detect the predominant chemical characterization of seahorses and investigate the mechanism by which seahorses exert antidepressant effects by using a chronic unpredictable mild stress (CUMS)-induced model of depression., Methods: Control and CUMS-exposed mice were fed normal or seahorse diet (0.018 g seahorses power) for 8-weeks. After behavioral tests, serum corticosterone, hippocampal expression of CD11b, glial fibrillary acidic protein (GFAP), and brain derived neurotrophic factor (BDNF), and the concentration of interleukin (IL)-1β and monoamine neurotransmitters were measured, while amygdala IL-1β and IL-10, anti-oxidative and oxidative enzyme were also studied. Then main phytoconstituents of seahorses was analyzed using liquid chromatography-mass spectrometry (LC-MS) methods., Results: Compared to controls, sucrose preference, exploration in open field, social interaction, entry numbers into and times spent on the open arms of elevated plus maze were significantly decreased, while immobility times in forced-swimming was increased in CUMS mice. These changes were associated with significantly reduced levels of serotonin, noradrenaline and dopamine, also expressions of GFAP and BDNF. Moreover, CUMS elevated IL-1β concentrations and reactive oxygen species (ROS), while decreased IL-10 concentration and anti-oxidative super oxide dismutase and glutathione peroxidase. Seahorse diet significantly reversed anxiety- and depression-like behaviors, which were correlated with reducing IL-1β and ROS, but increasing neurotransmitter concentrations and BDNF expression. Several compounds were found in seahorses, including docosahexaenoic acid, eicosapentaenoic acid, bis(2-ethylheptyl) phthalate, chrysophanol, and hypoxanthine., Conclusion: Seahorses could attenuate the CUMS-induced anxiety- and depression-like behaviors by reducing oxidative stress and inflammation, and normalizing neurotransmitter and neurotrophin function, which are possibly due to the activities of one or more or mixture of these identified compounds., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Patients with the Loeys-Dietz syndrome (LDS) have mutations in the TGF- β R1, TGF- β R2, and SMAD3 genes. However, little is known about the redox homeostasis in the thoracic aortic aneurysms (TAA) they develop. Here, we evaluate the oxidant/antioxidant profile in the TAA tissue from LDS patients and compare it with that in nondamaged aortic tissue from control (C) subjects. We evaluate the enzymatic activities of glutathione peroxidase (GPx), glutathione S-transferase (GST), glutathione reductase (GR), catalase (CAT), superoxide dismutase (SOD) isoforms, and thioredoxin reductase (TrxR). We also analyze some antioxidants from a nonenzymatic system such as selenium (Se), glutathione (GSH), and total antioxidant capacity (TAC). Oxidative stress markers such as lipid peroxidation and carbonylation, as well as xanthine oxidase (ORX) and nuclear factor erythroid 2-related factor 2 (Nrf2) expressions, were also evaluated. TAA from LDS patients showed a decrease in GSH, Se, TAC, GPx, GST, CAT, and TrxR. The SOD activity and ORX expressions were increased, but the Nrf2 expression was decreased. The results suggest that the redox homeostasis is altered in the TAA from LDS patients, favoring ROS overproduction that contributes to the decrease in GSH and TAC and leads to LPO and carbonylation. The decrease in Se and Nrf2 alters the activity and/or expression of some antioxidant enzymes, thus favoring a positive feedback oxidative background that contributes to the TAA formation., Competing Interests: All the authors declare that there are no competing interests regarding the publication of this paper., (Copyright © 2020 Maria Elena Soto et al.)

Besides their primary involvement in the recycling and degradation of proteins in endo-lysosomal compartments and also in specialized biological functions, cysteine cathepsins are pivotal proteolytic contributors of various deleterious diseases. While the molecular mechanisms of regulation via their natural inhibitors have been exhaustively studied, less is currently known about how their enzymatic activity is modulated during the redox imbalance associated with oxidative stress and their exposure resistance to oxidants. More specifically, there is only patchy information on the regulation of lung cysteine cathepsins, while the respiratory system is directly exposed to countless exogenous oxidants contained in dust, tobacco, combustion fumes, and industrial or domestic particles. Papain-like enzymes (clan CA, family C1, subfamily C1A) encompass a conserved catalytic thiolate-imidazolium pair (Cys25-His159) in their active site. Although the sulfhydryl group (with a low acidic pKa) is a potent nucleophile highly susceptible to chemical modifications, some cysteine cathepsins reveal an unanticipated resistance to oxidative stress. Besides an introductory chapter and peculiar attention to lung cysteine cathepsins, the purpose of this review is to afford a concise update of the current knowledge on molecular mechanisms associated with the regulation of cysteine cathepsins by redox balance and by oxidants (e.g., Michael acceptors, reactive oxygen, and nitrogen species)., Competing Interests: The authors declare no conflict of interest.

Oxidative stress has been reported to increase with aging, and although several age-related changes in redox parameters have been described, none of them have been verified as markers of the rate of aging and life span. Therefore, antioxidant (catalase, glutathione peroxidase, reductase activities, and reduced glutathione) and oxidant (oxidized glutathione, basal superoxide anion, and malondialdehyde concentrations) parameters were studied in whole blood cells from humans divided into different age groups (adult, mature, older adult, nonagenarian, and centenarian) in a cross-sectional study. Moreover, the same parameters were investigated in peritoneal leukocytes of mice at the analogous human ages (adult, mature, old, very old, and long-lived) in a longitudinal study as well as in adult prematurely aging mice. The results reveal that the age-related alterations of these markers are similar in humans and mice, with decreased antioxidants and increased oxidants in old participants, whereas long-lived individuals show similar values to those in adults. In addition, adult prematurely aging mice showed similar values to those in chronologically old mice and had a shorter life span than nonprematurely aging mice. Thus, these parameters could be proposed as markers of the rate of aging and used to ascertain biological age in humans., (© The Author(s) 2019. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Hydrogen peroxide (H 2 O 2 ) is a key redox intermediate generated within cells. Existing probes for H 2 O 2 have not solved the problem of detection of the ultra-low concentrations of the oxidant: these reporters are not sensitive enough, or pH-dependent, or insufficiently bright, or not functional in mammalian cells, or have poor dynamic range. Here we present HyPer7, the first bright, pH-stable, ultrafast, and ultrasensitive ratiometric H 2 O 2 probe. HyPer7 is fully functional in mammalian cells and in other higher eukaryotes. The probe consists of a circularly permuted GFP integrated into the ultrasensitive OxyR domain from Neisseria meningitidis. Using HyPer7, we were able to uncover the details of H 2 O 2 diffusion from the mitochondrial matrix, to find a functional output of H 2 O 2 gradients in polarized cells, and to prove the existence of H 2 O 2 gradients in wounded tissue in vivo. Overall, HyPer7 is a probe of choice for real-time H 2 O 2 imaging in various biological contexts., Competing Interests: Declaration of Interests The authors declare no competing financial interests., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Alpha-amanitin (α-AMA), the primary toxin of Amanita phalloides , is known to cause nephrotoxicity and hepatotoxicity. Resveratrol is an antioxidant that has shown efficacy in many nephrotoxicity models. The aim of this study was to investigate the effects of resveratrol against the early and late stages of α-AMA-induced nephrotoxicity, compared to those of silibinin, a well-known antidote for poisoning by α-AMA-containing mushrooms. Mice kidney tissues were obtained from five groups: (1) α-AMA + NS (simultaneous administration of α-AMA and normal saline), (2) α-AMA + SR (simultaneous administration of α-AMA and resveratrol), (3) α-AMA + 12R (resveratrol administration 12 h after α-AMA administration), (4) α-AMA + 24R (resveratrol administration 24 h after α-AMA administration), and (5) α-AMA + Sil (simultaneous administration of α-AMA and silibinin). Histomorphological and biochemical analyses were performed to evaluate kidney damage and oxidant-antioxidant status in the kidney. Scores of renal histomorphological damage decreased significantly in the early resveratrol treatment groups (α-AMA + SR and α-AMA + 12R), compared to those in the α-AMA + NS group ( p < 0.05). Catalase levels increased significantly in the α-AMA + SR group, compared to those in the α-AMA + NS group ( p < 0.001). Early resveratrol administration within 12 h after α-AMA ingestion may reverse the effects of α-AMA-induced nephrotoxicity, partly through its antioxidant action, thereby suggesting its potential as a treatment for poisoning by α-AMA-containing mushrooms.

The human gut pathogen, Salmonella Typhimurium (S. Typhimurium) not only survives but also replicates inside the phagocytic cells. Bacterial proteins are the primary targets of phagocyte generated oxidants. Because of the different amino acid composition, some proteins are more prone to oxidation than others. Many oxidant induced modifications to amino acids have been described. Introduction of carbonyl group is one of such modifications, which takes place quite early following exposure of proteins to oxidants and is quite stable. Therefore, carbonyl groups can be exploited to identify oxidant susceptible proteins. Hypochlorous acid (HOCl) is one of the most potent oxidants produced by phagocytes. Incubation of S. Typhimurium with 3 mM HOCl resulted in more than 150 folds loss of bacterial viability. Proteins extracted from HOCl exposed S. Typhimurium cells showed about 60 folds (p < 0.001) more carbonyl levels as compared to unexposed cells. Similarly, 2, 4-Dinitrophenylhydrazine (2, 4-DNPH) derivatized proteins of HOCl treated S. Typhimurium cultures reacted strongly with anti-DNP antibodies as compared to buffer treated counterpart. Next, we have derivatized carbonyl groups on the proteins with biotin hydrazide. The derivatized proteins were then isolated by avidin affinity chromatography. Mass spectrometry based analysis revealed the presence of 204 proteins.

Background: Lead (Pb) is ubiquitous in the environment and is an environmental genotoxic metal. Pb accumulation in the body could cause the oxidative stress., Objective: This meta-analysis aimed to perform a systematic evaluation of the extent of oxidative damage in rats/mice induced by lead., Methods: All relevant articles in English or Chinese were retrieved from Embase, PubMed, Web of Science, Medline, China National Knowledge Infrastructure, and Chinese Biological Medicine databases from their inception date until July 22, 2018., Results: A total of 108 eligible articles were included in this study. The indicators of oxidative stress included malondialdehyde (MDA), glutathione disulfide (GSSG), reactive oxygen species (ROS), hydrogen peroxide (H 2 O 2 ), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), reduced glutathione (GSH), superoxide dismutase (SOD), and glutathione-s-transferase (GST). The meta-analysis showed that lead significantly increased oxidants levels, such as MDA, GSSG, ROS, and H 2 O 2 (P < 0.05), and significantly reduced the level of antioxidants, such as CAT, GPx, GR, GSH, SOD, and GST (P < 0.05). The intraperitoneal mode was more effective than water drinking mode in reducing the levels of CAT, GPx, GSH, and SOD (P < 0.05). Other factors that influenced the overall oxidative stress, including species of animals, type of tissues, and intervention dosage and time, were comprehensively evaluated., Conclusion: The results of meta-analysis indicated that mice were more sensitive to lead than rats, and intraperitoneal mode was an effective intervention mean. High doses and long periods of lead treatment can cause serious oxidative damage. Moreover, testicular was more vulnerable to lead than other tissues. These results provided scientific evidence for preventing and treating lead toxicity., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 Elsevier GmbH. All rights reserved.)

The nuclear transcription factor p53, discovered in 1979, has a broad range of biological functions, primarily the regulation of apoptosis, the cell cycle, and DNA repair. In addition to these canonical functions, a growing body of evidence suggests that p53 plays an important role in regulating intracellular redox homeostasis through transcriptional and nontranscriptional mechanisms. Oxidative stress induction and p53 activation are common responses to chemical exposure and are suggested to play critical roles in chemical-induced toxicity. The activation of p53 can exert either prooxidant or antioxidant activity, depending on the context. In this review, we discuss the functional role of p53 in regulating chemical-induced oxidative stress, summarize the potential signaling pathways involved in p53's regulation of chemically mediated oxidative stress, and propose issues that should be addressed in future studies to improve understanding of the relationship between p53 and chemical-induced oxidative stress., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 Xiaoyi Liu et al.)

Felids have a high incidence of chronic kidney disease (CKD), for which the most common renal lesion is chronic interstitial nephritis (CIN). CIN can be induced by tissue oxidative stress, which is determined by the cellular balance of pro- and anti-oxidant metabolites. Fish-flavoured foods are more often fed to cats than dogs, and such foods tend to have higher arsenic content. Arsenic is a pro-oxidant metallic element. We propose that renal accumulation of pro-oxidant elements such as arsenic and depletion of anti-oxidant elements such as zinc, underpin the high incidence of CIN in domestic cats. Total arsenic and other redox-reactive metal elements were measured in kidneys (after acid-digestion) and urine (both by inductively-coupled plasma-mass spectrometry) of domestic cats (kidneys, n = 56; urine, n = 21), domestic dogs (kidneys, n = 54; urine, n = 28) and non-domesticated Scottish Wildcats (kidneys, n = 17). Renal lesions were graded by severity of CIN. In our randomly sampled population, CIN was more prevalent in domestic cat versus domestic dog (51%, n = 32 of 62 cats; 15%, 11 of 70 dogs were positive for CIN, respectively). CIN was absent from all Scottish wildcats. Tissue and urinary (corrected for creatinine) arsenic content was higher in domestic cats, relative to domestic dogs and wildcats. Urine arsenic was higher in domestic cats and dogs with CIN. Arsenobetaine, an organic and relatively harmless species of arsenic, was the primary form of arsenic found in pet foods. In summary, the kidneys of domestic cats appear to have greater levels of pro-oxidant trace elements, as compared to dogs and wildcats. Since there was no difference in renal arsenic levels in cats with or without CIN, renal arsenic accumulation does not appear a primary driver of excess CIN in cats. Given clear differences in renal handling of pro vs. anti-oxidant minerals between cats and dogs, further in vivo balance studies are warranted. These may then inform species-specific guidelines for trace element incorporation into commercial diets.

Background: Paraoxonase 1 (PON1) is a calcium-dependent multifunctional enzyme that binds to high-density lipoproteins. The physiological function of PON1 is related to its lactonase activity. However, this activity has not been analyzed in women with gestational diabetes mellitus (GDM). The present study investigated the lactonase activities and status of PON1 and their association with PON1 genetic variants and oxidative stress indices in Chinese women with GDM., Methods: This is a case-control study of 347 women with GDM and 288 women with uncomplicated pregnancies. PON1 levels and lactonase activities were analyzed using 7-O-diethylphosphoryl-3-cyano-4-methyl-7-hydroxycoumarin (DEPCyMC) and 5-thiobutyl butyrolactone (TBBL), respectively. A normalized lactonase activity (NLA) was estimated based on the ratio of TBBLase to DEPCyMCase activity. Serum malondialdehyde (MDA), total oxidant status (TOS), total antioxidant capacity (TAC) levels, and PON1 genetic variants and oxidative stress indices in Chinese women with GDM., Results: PON1 lactonase activity and levels of TOS, TAC, and MDA were higher in the GDM women compared with the control women. The PON1 -108C→T genetic variation decreased the levels and lactonase activities of PON1 in a genotype-dependent manner in the patient and control groups. GDM patients with the PON1 -108TT genotype displayed lower NLA than those with the -108CC or -108CT genotype. GDM patients with the RR genotype of PON1 192Q/R polymorphism had significantly lower PON1 lactonase activities and NLA and tended to have decreased PON1 levels compared with those with the QQ or QR genotype. Multivariable regression analysis revealed that the PON1 -108C/T or 192Q/R variations, apolipoprotein (apo) A1, apoB, TAC, MDA, or age was significant predictors of the levels, lactonase activities, or NLA of PON1., Conclusions: The lactonase activities of PON1 are increased in women with GDM. PON1 genetic variants, increased oxidative stress, and abnormalities in lipoproteins may be associated with these changes. PON1 genetic variants and oxidative stress indices in Chinese women with GDM., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this article., (Copyright © 2020 Mi Zhou et al.)

Carnosine is a natural endogenous dipeptide widely distributed in mammalian tissues, existing at particularly high concentrations in the muscles and brain and possesses well-characterized antioxidant and anti-inflammatory activities. In an in vitro model of macrophage activation, induced by lipopolysaccharide + interferon-gamma (LPS + IFN-γ), we here report the ability of carnosine to modulate pro-oxidant and pro-inflammatory activities of macrophages, representing the primary cell type that is activated as a part of the immune response. An ample set of parameters aimed to evaluate cytotoxicity (MTT assay), energy metabolism (HPLC), gene expressions (high-throughput real-time PCR (qRT-PCR)), protein expressions (western blot) and nitric oxide production (qRT-PCR and HPLC), was used to assess the effects of carnosine on activated macrophages challenged with a non cytotoxic LPS (100 ng/mL) + IFN-γ (600 U/mL) concentration. In our experimental model, main carnosine beneficial effects were: (1) the modulation of nitric oxide production and metabolism; (2) the amelioration of the macrophage energy state; (3) the decrease of the expressions of pro-oxidant enzymes (Nox-2, Cox-2) and of the lipid peroxidation product malondialdehyde; (4) the restoration and/or increase of the expressions of antioxidant enzymes (Gpx1, SOD-2 and Cat); (5) the increase of the transforming growth factor-β1 (TGF-β1) and the down-regulation of the expressions of interleukins 1β and 6 (IL-1β and IL-6) and 6) the increase of the expressions of Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and heme oxygenase-1 (HO-1). According to these results carnosine is worth being tested in the treatment of diseases characterized by elevated levels of oxidative stress and inflammation (atherosclerosis, cancer, depression, metabolic syndrome, and neurodegenerative diseases).

Our objective was to evaluate the effects of diet starch concentration and starch fermentability on inflammatory response markers and oxidant status during the early postpartum (PP) period and its carryover effects. Fifty-two multiparous Holstein cows were used in a completely randomized block design experiment with a 2 × 2 factorial arrangement of treatments. Treatments were starch concentration and starch fermentability of diets; diets were formulated to 22% (low starch, LS) or 28% (high starch, HS) starch with dry-ground corn (DGC) or high-moisture corn (HMC) as the primary starch source. Treatments were fed from 1 to 23 d PP and then switched to a common diet until 72 d PP to measure carryover (CO) effects. Treatment period (TP) diets were formulated to 22% forage neutral detergent fiber and 17% crude protein. The diet for the CO period was formulated to 20% forage neutral detergent fiber, 17% crude protein, and 29% starch. Coccygeal blood was collected once a week during the TP and every second week during the CO period. Liver and adipose tissue biopsies were performed within 2 d PP and at 20 ± 3 d PP. Blood plasma was analyzed for concentrations of albumin, haptoglobin, reactive oxygen and nitrogen species (RONS), and antioxidant potential (AOP), with lipopolysaccharide-binding protein (LBP) and TNFα evaluated during the TP only. Oxidative stress index (OSi) was calculated as RONS/AOP. Abundance of mRNA from genes involved in inflammation and glucose metabolism in liver and genes involved in lipogenesis in adipose tissue were determined. Data were analyzed separately for the TP and CO periods. During the TP, treatments interacted to affect concentrations of TNFα, haptoglobin, and LBP, with HMC increasing their concentrations for HS (9.38 vs. 7.45 pg/mL, 0.45 vs. 0.37 mg/mL, and 5.94 vs. 4.48 μg/mL, respectively) and decreasing their concentrations for LS (4.76 vs. 12.9 pg/mL, 0.27 vs. 0.41 mg/mL, and 4.30 vs. 5.87 μg/mL, respectively) compared with DGC. Effects of treatments diminished over time for LBP and haptoglobin with no differences by the end of the TP and no main CO effects of treatment for haptoglobin. The opposite treatment interaction was observed for albumin, with HMC tending to decrease its concentration for HS (3.24 vs. 3.34 g/dL) and increase its concentration for LS (3.35 vs. 3.29 g/dL) compared with DGC, with no carryover effect. Feeding DGC increased the OSi during the first week of the TP compared with HMC, with this effect diminishing over time; during the CO period HMC increased OSi for HS and decreased it for LS compared with DGC, with this effect diminishing toward the end of CO. Feeding HMC increased the abundance of genes associated with inflammation and gluconeogenesis in liver for HS and decreased it for LS compared with DGC. Feeding HS increased the mRNA abundance of genes associated with adipose tissue lipogenesis compared with LS. Results during the TP suggest that feeding LS-DGC and HS-HMC elicited a more pronounced inflammatory response and induced an upregulation of genes associated with inflammation and gluconeogenesis in liver, without effects on OSi, but effects on plasma markers of inflammation diminished during the CO period., (Copyright © 2020 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

Background: Mechanical ventilation (MV) is identified as an independent contributor to diaphragmatic atrophy and contractile dysfunction. Appropriate sedation is also essential during MV, and anesthetics may have direct adverse effects on the diaphragm. However, there is a lack of research into the effects of different anesthetics on diaphragm function during MV., Objectives: In the present study, we aim to examine the effect of midazolam, dexmedetomidine, and propofol on diaphragm function during MV., Design: Animal study., Setting: University research laboratory., Subjects: Male Wistar rats., Interventions: Animals were experienced 12 h of MV or spontaneous breathing (SB) with continuous anesthetics infusion. Diaphragm contractile properties, cross-sectional areas, microcirculation, oxidative stress, and proteolysis were examined., Measurements and Main Results: Diaphragmatic specific force was markedly reduced in the midazolam group compared with the dexmedetomidine (-60.4 ± 3.01%, p < 0.001) and propofol group (-58.3 ± 2.60%, p < 0.001) after MV. MV sedated with midazolam induced more atrophy of type II fibers compared with dexmedetomidine (-21.8 ± 2.11%, p = 0.0001) and propofol (-8.2 ± 1.53%, p = 0.003). No significant differences of these indices were found in the midazolam, dexmedetomidine, and propofol groups under SB condition (all p > 0.05, respectively). Twelve hours of MV resulted in a time dependent reduction in diaphragmatic functional capillary density (PB -25.1%, p = 0.0001; MZ -21.6%, p = 0.0003; DD -15.2%, p = 0.022; PP -24.8%, p = 0.0001, respectively), which did not occur in the gastrocnemius muscle. The diaphragmatic lipid peroxidation adducts 4-HNE and HIF-1α levels were significantly lower in dexmedetomidine group and propofol group compared to midazolam group (p < 0.05, respectively). Meanwhile, the catalase and SOD levels were also relatively lower (p < 0.05, respectively) in midazolam group compared to dexmedetomidine group and propofol group., Conclusions: Twelve hours of mechanical ventilation during midazolam sedation led to a more severe diaphragm dysfunction than dexmedetomidine and propofol, possibly caused by its relative weaker antioxidant capacity., (Copyright © 2019 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Introduction and Objectives: Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) co-infection generates sustained inflammation with increased reactive oxygen species production. The pathogenic impact of systemic oxidative stress is known to influence drug treatment and follow-up. The aim of this case-control study was to compare the redox status in HCV-HIV co-infected with respect to HIV-infected individuals and to explore the relation between redox and HIV follow-up variables., Patients or Materials and Methods: Blood samples were drawn from 330 individuals divided into three groups: HIV, HCV-HIV and presumable healthy subjects. Redox, hematological, hemochemical, immunologic and virological indexes were determined., Results: Both HIV groups had significant differences in global indexes of damage and antioxidant status (p<0.05) with respect to the supposedly healthy individual group. HCV-HIV group showed a significantly higher damage (total hydroperoxide and advanced oxidation protein products) compared to the control and HIV groups (p<0.05). The overall modification of the redox indexes showed that 72% of individuals with simultaneous detrimental differences were related to HCV-HIV condition., Conclusions: These results corroborate that oxidative stress occurs in the HIV condition and also during HCV-HIV co-infection, with different molecular changes of follow-up indexes. Redox indexes diagnosis should be considered in early diagnosis and treatment of HCV-HIV co-infection., (Copyright © 2019 Fundación Clínica Médica Sur, A.C. Published by Elsevier España, S.L.U. All rights reserved.)

The aim of the study was to evaluate the potential protective role of sildenafil and tadalafil in contrast-induced nephropathy (CIN) by modulating oxidative stress. Thirty Wistar male rats were equally assigned into five groups: sham, CIN, CIN + sildenafil (10 mg/kg bw/day), CIN + tadalafil (5 mg/kg bw/day) and CIN + N-Acetyl Cysteine (NAC) (100 mg/kg bw/day) as a positive control. CIN was induced by 12 h dehydration and administration of indomethacin (10 mg/kg bw), N-ω- nitro-L-arginine methyl ester (10 mg/kg bw), and iopromide (3 g/kg bw iodine). Blood was drawn prior to and 24 h after CIN induction for evaluating renal function and oxidative stress. In the CIN group, total antioxidant capacity (TAC), reduced glutathione (GSH) and catalase (CAT) levels were significantly decreased; and protein carbonyl (PROTC) and thiobarbituric reactive species (TBARS) were significantly increased compared to the sham group. Pre- Sildenafil and tadalafil pre-treatment reduced CIN risk and reversed oxidative stress almost to the sham group levels. These results suggest that PDE5Is can be good candidates for preventing CIN based on their ability to modulate the oxidant/antioxidant balance., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The aim of this study was to evaluate changes in the antioxidant status and oxidative stress parameters in plasma and saliva in order to investigate the physiological conditions of dairy cows. Blood and saliva were collected from clinically healthy female calves (n = 18), sexually mature, non-pregnant cows (n = 19), and pregnant dairy cows (n = 15). Spectrophotometric and spectroflurimetric analyses were carried out in the body fluids of these animals. The level of total antioxidant capacity (TAC) in plasma reached the lowest (p < 0.05) value in the group of sexually mature, non-pregnant cows (2.375 ± 0.500 μmol/g). A significant negative correlation (tau b = - 0.248, p < 0.05) was found between TAC values detected in plasma and saliva of examined animals. The highest (p < 0.05) mean values of thiol groups were detected in both plasma (0.007 ± 0.0015 mmol/g) and saliva (0.276 ± 0,116 mmol/g) of mature, non‑pregnant cows. Conversely, the highest (p < 0.05) levels of formylokinurenine concentration were detected in saliva (11.535 ± 3.785 μg/mg) and plasma (0.133 ± 0.0237 μg/mg) of pregnant dairy cows. A significant positive correlation (tau b = 0.255, p < 0.05) was also found between the bityrosine content detected in plasma and saliva of the examined cows. In conclusion, although with regards to antioxidant/oxidative parameters saliva reflects the content of plasma only in part, however it shows age-related differences that can be used in the description of the physiological status of cows.

The toxicity of oxygen and nitrogen reactive species appears to be merely the tip of the iceberg in the world of redox homeostasis. Now, oxidative stress can be seen as a two-sided process; at high concentrations, it causes damage to biomolecules, and thus, trypanosomes have evolved a strong antioxidant defense system to cope with these stressors. At low concentrations, oxidants are essential for cell signaling, and in fact, the oxidants/antioxidants balance may be able to trigger different cell fates. In this comprehensive review, we discuss the current knowledge of the oxidant environment experienced by T. cruzi along the different phases of its life cycle, and the molecular tools exploited by this pathogen to deal with oxidative stress, for better or worse. Further, we discuss the possible redox-regulated processes that could be governed by this oxidative context. Most of the current research has addressed the importance of the trypanosomes' antioxidant network based on its detox activity of harmful species; however, new efforts are necessary to highlight other functions of this network and the mechanisms underlying the fine regulation of the defense machinery, as this represents a master key to hinder crucial pathogen functions. Understanding the relevance of this balance keeper program in parasite biology will give us new perspectives to delineate improved treatment strategies., (Copyright © 2019 Mesías, Garg and Zago.)

In this study, we have investigated the effects of different doses of thymol (T) and carvacrol (C) on sperm quality oxidative stress and antioxidant system. For this purpose, 49 rats were divided into seven groups (7 rats in each group): 1st Group (control); 2nd Group T-10 (thymol 10 mg/kg), 3rd Group T-20 (thymol 20 mg/kg), 4th Group C-10 (carvacrol 10 mg/kg), 5th Group C-20 (carvacrol 20 mg/kg), 6th Group T + C-10 (thymol 10 mg/kg + carvacrol 10 mg/kg) and 7th Group T + C-20 (thymol 20 mg/kg + carvacrol 20 mg/kg). The duration of the experiment was 10 weeks for all animals. During the study, sperm quality parameters (motility, concentration, abnormal spermatozoa and live-dead sperm ratio), biochemical parameters [malondialdehyde (MDA), reduced glutathione(GSH), glutathione peroxidase (GSH-Px), catalase (CAT), AST, ALT, GGT, urea and creatinine] were analysed, and histopathological examination was performed. The study results showed that monotherapies of thymol and carvacrol significantly decreased MDA levels in testicles, liver and kidney tissues compared to the control group ( p  < .001). GSH levels increased only with the thymol administration and GSH-Px and catalase activity increased only with the carvacrol administration compared to the control group ( p  < .05). The combined administration of these two agents did not cause any significant change in any parameter. Regarding the sperm quality parameters, only the spermatozoa concentration and motility increased significantly in the thymol and carvacrol groups compared to the control group ( p  < .01). However, these parameters decreased in the 7th Group (T + C-20) compared to the control group ( p  < .001). Considering the dead sperm ratio decreased significantly in the 2nd (T-10), 3rd (T-20), 4th (C-10), 5th (C-20) and 6th Group (T + C-10) compared to the control group ( p  < .001). In respect of spermatozoon anomaly, there was a significant decrease in thymol and carvacrol monotherapy groups. The histopathological analysis of the testicle, liver and kidney tissues of the animals showed no difference between the groups. In conclusion, we have determined that thymol and carvacrol administration decreased the oxidative damage and increased the antioxidant levels and improved the sperm quality parameters. However, the combined use of these two active ingredients had a limited therapeutic effect on the mentioned parameters.

Several evidences from the literature showed that the coexistence of nickel and zinc in polluted waters is related to the similarity in their geogenic and anthropogenic factors. Although most environmental exposures to metals do not occur singly, there is a paucity of scientific knowledge on the effects of zinc and nickel co-exposure on mammalian reproductive health. The present study investigated the influence of co-exposure to nickel and zinc on male reproductive function in rats. Experimental rats were co-exposed to environmentally relevant concentrations of waterborne nickel (75 and 150 μg NiCl 2 L -1 ) and zinc (100 and 200 μg ZnCl 2 L -1 ) for 45 successive days. Subsequently, reproductive hormones were assayed whereas the hypothalamus, epididymis and testes of the rats were processed for the assessment of oxidative stress and inflammation indices, caspase-3 activity and histology. Results indicated that co-exposure to nickel and zinc significantly (p < 0.05) abolished nickel-mediated diminution of antioxidant defense mechanisms while diminishing levels of reactive oxygen and nitrogen species and lipid peroxidation in the hypothalamus, epididymis and testes of the exposed rats. Additionally, co-exposure to zinc abated nickel-mediated diminutions in luteinizing hormone, follicle-stimulating hormone, serum and intra-testicular testosterone with concomitant enhancement of sperm production and quality. Further, zinc abrogated nickel-mediated elevation in inflammatory biomarkers including nitric oxide, tumor necrosis factor alpha, interleukin-1 beta as well as caspase-3 activity. The protective influence of zinc on nicked-induced reproductive toxicity was well supported by histological data. Overall, zinc ameliorated nickel-induced reproductive dysfunction via its anti-oxidant, anti-inflammatory, anti-apoptotic and spermato-protective activities in rats., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Cerium oxide nanoparticles (CeO 2 NPs) possess powerful antioxidant properties, thus emerging as a potential therapeutic tool in non-alcoholic fatty liver disease (NAFLD) progression, which is characterized by a high presence of reactive oxygen species (ROS). The aim of this study was to elucidate whether CeO 2 NPs can prevent or attenuate oxidant injury in the hepatic human cell line HepG2 and to investigate the mechanisms involved in this phenomenon. The effect of CeO 2 NPs on cell viability and ROS scavenging was determined, the differential expression of pro-inflammatory and oxidative stress-related genes was analyzed, and a proteomic analysis was performed to assess the impact of CeO 2 NPs on cell phosphorylation in human hepatic cells under oxidative stress conditions. CeO 2 NPs did not modify HepG2 cell viability in basal conditions but reduced H 2 O 2 - and lipopolysaccharide (LPS)-induced cell death and prevented H 2 O 2 -induced overexpression of MPO, PTGS1 and iNOS. Phosphoproteomic analysis showed that CeO 2 NPs reverted the H 2 O 2 -mediated increase in the phosphorylation of peptides related to cellular proliferation, stress response, and gene transcription regulation, and interfered with H 2 O 2 effects on mTOR, MAPK/ERK, CK2A1 and PKACA signaling pathways. In conclusion, CeO 2 NPs protect HepG2 cells from cell-induced oxidative damage, reducing ROS generation and inflammatory gene expression as well as regulation of kinase-driven cell survival pathways.

Significance: Idiopathic pulmonary fibrosis (IPF) is a progressive age-related lung disease with a median survival of only 3 years after diagnosis. The pathogenic mechanisms behind IPF are not clearly understood, and current therapeutic approaches have not been successful in improving disease outcomes. Recent Advances: IPF is characterized by increased production of reactive oxygen species (ROS), primarily by NADPH oxidases (NOXes) and mitochondria, as well as altered antioxidant defenses. Recent studies have identified the NOX isoform NOX4 as a key player in various important aspects of IPF pathology. In addition, mitochondrial dysfunction is thought to enhance pathological features of IPF, in part by increasing mitochondrial ROS (mtROS) production and altering cellular metabolism. Recent findings indicate reciprocal interactions between NOX enzymes and mitochondria, which affect regulation of NOX activity as well as mitochondrial function and mtROS production, and collectively promote epithelial injury and profibrotic signaling. Critical Issues and Future Directions: The precise molecular mechanisms by which ROS from NOX or mitochondria contribute to IPF pathology are not known. This review summarizes the current knowledge with respect to the various aspects of ROS imbalance in the context of IPF and its proposed roles in disease development, with specific emphasis on the importance of inappropriate NOX activation, mitochondrial dysfunction, and the emerging evidence of NOX-mitochondria cross-talk as important drivers in IPF pathobiology.

Pyruvate kinase M2 is a critical enzyme that regulates cell metabolism and growth under different physiological conditions. In its metabolic role, pyruvate kinase M2 catalyzes the last glycolytic step which converts phosphoenolpyruvate to pyruvate with the generation of ATP. Beyond this metabolic role in glycolysis, PKM2 regulates gene expression in the nucleus, phosphorylates several essential proteins that regulate major cell signaling pathways, and contribute to the redox homeostasis of cancer cells. The expression of PKM2 has been demonstrated to be significantly elevated in several types of cancer, and the overall inflammatory response. The unusual pattern of PKM2 expression inspired scientists to investigate the unrevealed functions of PKM2 and the therapeutic potential of targeting PKM2 in cancer and other disorders. Therefore, the purpose of this review is to discuss the mechanistic and therapeutic potential of targeting PKM2 with the focus on cancer metabolism, redox homeostasis, inflammation, and metabolic disorders. This review highlights and provides insight into the metabolic and non-metabolic functions of PKM2 and its relevant association with health and disease., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background/aim: Oxidative stress plays an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). Smoking is the leading source of oxidants in lungs. However, it is currently unknown why some individuals are more resistant to the detrimental effects of smoking and do not develop COPD. The aim in this study is to measure and compare the oxidant/antioxidant balance between in non-COPD individuals who smoke and COPD patients who smoke., Materials and Methods: Included in the study were 137 patients with COPD and 102 healthy individuals. Participants were divided into groups as COPD patients (former and current smokers), non-COPD individuals who smoke and non-smokers healthy persons. In the following stage, the total antioxidant status (TAS), total oxidant status (TOS) and oxidative stress index (OSI) levels were measured in serum for all participants., Results: In the current-smoker COPD group, the level of oxidant status were significantly higher than the former-smoker COPD group (p < 0.001). Similarly, oxidant levels were significantly high in current-smoker healthy group than never smoker healthy group. According to these results TOS was associated with especially smoking status rather than COPD. Antioxidant status were similar between former-smoker COPD group and current-smoker COPD group. The antioxidant levels were found significantly low in current-smoker COPD patients, compared to the current-smoker non-COPD individuals (p = 0.007). Nevertheless, no significant difference was found in OSI levels between two groups. Briefly, high TOS and OSI values were correlated with only smoking, independently from COPD., Conclusion: It was concluded that there are complex pathogenetic mechanisms, including genetic and individual variations other than oxidant/antioxidant balance, involved in the development of smoking-related COPD. TOS and OSI values are not predictive parameters for the development of COPD, but high level of TAS in non-COPD smokers is promising for future studies., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Excessive oxidative stress and inflammation are the key early events in the development of intervertebral disc degeneration (IVDD). The NACHT, LRR, and PYD domain-containing protein 3 (NLRP3) inflammasome has been identified as the major source of oxidative stress and the inflammatory responses and thus is an attractive therapeutic target for IVDD. However, currently, there are no reports on the use of mesenchymal stem cell (MSC)-derived exosomes to reduce NLRP3 inflammasome expression for IVDD treatment. The present study aimed to investigate the therapeutic effect of exosomes for use as IVDD therapeutics. We first manufactured and evaluated the characteristics of exosomes. Then, we investigated the effects of exosomes on H 2 O 2 -induced nucleus pulposus (NP) cell inflammation. Third, we tested the function of exosomes with respect to H 2 O 2 -induced ROS production and mitochondrial dysfunction. Finally, the therapeutic effect of exosomes on IVDD was investigated using a rabbit IVDD model. Results showed that exosomes play an anti-inflammatory role in pathological NP cells by suppressing inflammatory mediators and NLRP3 inflammasome activation. Moreover, it was suggested that exosomes might supply mitochondrial proteins to NP cells, and that the damaged mitochondria could be restored with this supplement. Further, in the rabbit IVDD model, exosomes significantly prevented the progression of degenerative changes. Our results confirmed that the NLRP3 inflammasome is an effective target for IVDD treatment and that the injection of exosomes could be a promising therapeutic strategy., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Peroxiredoxins (Prxs) detoxify hydrogen peroxide (H 2 O 2 ), peroxynitrite, and various organic hydroperoxides. However, the differential oxidative status of Prxs reacted with each peroxide remains unclear. In the present study, we focused on the oxidative alteration of Prxs and demonstrated that, in human red blood cells (RBCs), peroxiredoxin 2 (Prx2) is readily reactive with H 2 O 2 , forming disulfide dimers, but was not easily hyperoxidized. In contrast, Prx2 was highly sensitive to the relatively hydrophobic oxidants, such as tert-butyl hydroperoxide (t-BHP) and cumene hydroperoxide. These peroxides hyperoxidized Prx2 into oxidatively damaged forms in RBCs. The t-BHP treatment formed hyperoxidized Prx2 in a dose-dependent manner. When organic hydroperoxide-treated RBC lysates were subjected to reverse-phase high performance liquid chromatography, two peaks derived from hyperoxidized Prx2 appeared along with the decrease of that corresponding to native Prx2. Liquid chromatography-tandem mass spectrometry analysis clearly showed that hyperoxidation to sulfonic acid (-SO 3 H) at Cys-51 residue was more advanced in a newfound hyperoxidized Prx2 compared to another hydrophobic hyperoxidized form previously identified. These results indicate that irreversible hyperoxidation of the Prx2 monomer in RBCs was easily caused by organic hydroperoxide but not H 2 O 2 . Thus, it is important to detect the hyperoxidation of Prx2 into sulfinic or sulfonic acid derivates of Cys-51 because hyperoxidized Prx2 is a potential marker of oxidative injury caused by organic hydroperoxides in human RBCs., (Copyright © 2019 Elsevier Inc. All rights reserved.)

To determine the role of denervation and motor unit turnover in the age-related increase in skeletal muscle oxidative stress, the hydrogen peroxide (H 2 O 2 ) specific, genetically-encoded, fluorescent cyto-HyPer2 probe was expressed in mouse anterior tibialis (AT) muscle and compared with ex vivo measurements of mitochondrial oxidant generation. Crush of the peroneal nerve induced increased mitochondrial peroxide generation, measured in permeabilised AT fibers ex vivo and intra vital confocal microscopy of cyto-HyPer2 fluorescence showed increased cytosolic H 2 O 2 in a sub-set (~24%) of individual fibers associated with onset of fiber atrophy. In comparison, mitochondrial peroxide generation was also increased in resting muscle from old (26 month) mice compared with adult (6-8 month) mice, but no age effect on fiber cytosolic H 2 O 2 in vivo was seen. Thus ageing is associated with an increased ability of muscle fibers to maintain cytosolic redox homeostasis in the presence of denervation-induced increase in mitochondrial peroxide generation.

Motile cilia on airway cells are necessary for clearance of mucus-trapped particles out of the lung. Ciliated airway epithelial cells are uniquely exposed to oxidants through trapping of particles, debris and pathogens in mucus and the direct exposure to inhaled oxidant gases. Dynein ATPases, the motors driving ciliary motility, are sensitive to the local redox environment within each cilium. Several redox-sensitive cilia-localized proteins modulate dynein activity and include Protein Kinase A, Protein Kinase C, and Protein Phosphatase 1. Moreover, cilia are rich in known redox regulatory proteins and thioredoxin domain-containing proteins that are critical in maintaining a balanced redox environment. Importantly, a nonsense mutation in TXNDC3, which contains a thioredoxin motif, has recently been identified as disease-causing in Primary Ciliary Dyskinesia, a hereditary motile cilia disease resulting in impaired mucociliary clearance. Here we review current understanding of the role(s) oxidant species play in modifying airway ciliary function. We focus on oxidants generated in the airways, cilia redox targets that modulate ciliary beating and imbalances in redox state that impact health and disease. Finally, we review disease models such as smoking, asthma, alcohol drinking, and infections as well as the direct application of oxidants that implicate redox balance as a modulator of cilia motility., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Transient receptor potential melastatin channel subfamily member 2 (TRPM2) has an essential role in protecting cell viability through modulation of oxidative stress. TRPM2 is highly expressed in cancer. When TRPM2 is inhibited, mitochondria are dysfunctional, ROS levels are increased, and cell viability is reduced. Here, the importance of NF-E2-related factor (Nrf2) in TRPM2-mediated suppression of oxidant stress was explored. In TRPM2 depleted cells, antioxidant cofactors glutathione, NADPH, and NADH were significantly reduced. Cytoplasmic and nuclear expression of Nrf2 and of IQGAP1, a modulator of Nrf2 stability regulated by intracellular calcium, were decreased. Antioxidant enzymes transcriptionally regulated by Nrf2 and involved in GSH, NADPH, and NADH generation were significantly lower including PRX1 and PRX3, GPX4, GSTP1, GCLC, and MTHFD2. The glutamine pathway leading to GSH production was suppressed, and ATP and GTP levels were impaired. Reconstitution with wild type TRPM2 or Nrf2, but not TRPM2 pore mutant E960D, rescued expression of enzymes downstream of Nrf2 and restored GSH and GTP. Cell viability, ROS, NADPH, NADH, and ATP levels were fully rescued by TRPM2 and partially by Nrf2. These data show that TRPM2 maintains cell survival following oxidative stress through modulation of antioxidant pathways and cofactors regulated by Nrf2.

The phagocyte NADPH oxidase possesses a transmembrane electron transferase comprised of gp91phox (aka NOX2) and p22phox and two multicomponent cytosolic complexes, which in stimulated phagocytes translocate to assemble a functional enzyme complex at plasma or phagosomal membranes. The NOX2-centered NADPH oxidase shuttles electrons from cytoplasmic NADPH to molecular oxygen in phagosomes or the extracellular space to produce oxidants that support optimal antimicrobial activity by phagocytes. Additionally, NOX2-generated oxidants have been implicated in both autocrine and paracrine signaling in a variety of biological contexts. However, when interpreting experimental results, investigators must recognize the complexity inherent in the biochemistry of oxidant-mediated attack of microbial targets and the technical limitations of the probes currently used to detect intracellular oxidants., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Thioredoxin (Trx) is a conserved, cytosolic reductase in all known organisms. The enzyme receives two electrons from NADPH via thioredoxin reductase (TrxR) and passes them on to multiple cellular reductases via disulfide exchange. Despite the ubiquity of thioredoxins in all taxa, little is known about the functions of resurrected ancestral thioredoxins in the context of a modern mesophilic organism. Here, we report on functional in vitro and in vivo analyses of seven resurrected Precambrian thioredoxins, dating back 1-4 billion years, in the Escherichia coli cytoplasm. Using synthetic gene constructs for recombinant expression of the ancestral enzymes, along with thermodynamic and kinetic assays, we show that all ancestral thioredoxins, as today's thioredoxins, exhibit strongly reducing redox potentials, suggesting that thioredoxins served as catalysts of cellular reduction reactions from the beginning of evolution, even before the oxygen catastrophe. A detailed, quantitative characterization of their interactions with the electron donor TrxR from Escherichia coli and the electron acceptor methionine sulfoxide reductase, also from E. coli , strongly hinted that thioredoxins and thioredoxin reductases co-evolved and that the promiscuity of thioredoxins toward downstream electron acceptors was maintained during evolution. In summary, our findings suggest that thioredoxins evolved high specificity for their sole electron donor TrxR while maintaining promiscuity to their multiple electron acceptors., (© 2019 Napolitano et al.)

Aims: Doxorubicin, an anticancer drug, has a toxic effect on many tissues such as heart, pancreas, liver, kidney, and testis. The aim of current study is to investigate whether melatonin would be protective in doxorubicin-induced beta (β) cell toxicity via HMGB1/TLR2/TLR4/MAPK/NF-қB signaling pathway., Main Methods: Human pancreatic β cell (1.1B4) was used in the present study. Four experimental groups were created as control, melatonin (10 μM), doxorubicin (2 μM) and the combination of melatonin with doxorubicin. Following 24-h treatment, Mitogen-activated protein kinase (MAPKs), Toll like receptors (TLRs) including TLR2 and TLR4, pro-and anti-apoptotic protein expression levels were determined by western blotting. Total antioxidant (TAS), oxidant status (TOS) and oxidative stress index (OSI) of the cells as well as superoxide dismutase (SOD) levels were determined. Active caspase-8 activity was measured and TUNEL staining was performed to study apoptotic pathways. Mitochondrial membrane potential (MMP), some protein expressions and F-actin distribution were analyzed., Key Findings: Doxorubicin caused to depolarize MMP, resulting in enhancing apoptosis by activation of caspase-8 via MAPKs/NF-кB pathway via elevation of TOS and decreasing TAS. Also, doxorubicin destroyed F-actin distribution and elevated TLR2 and some apoptotic proteins, including Bax. However, co-treatment of melatonin with doxorubicin could reverse depolarization of MMP and inhibition of apoptosis through MAPK/NF-кB signaling by decreasing TOS and increasing TAS. The co-treatment reversed the alternations of TLR2, TLR4, MAPKs and apoptotic protein expressions induced by doxorubicin., Significance: Melatonin could be a good candidate against pancreatic β cell toxicity-induced by doxorubicin through TLR2/TLR4/MAPK/NF-кB pathways., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Parkinson's disease (PD) is defined as a chronic neurodegenerative disorder which is diagnosed mostly by its clinical manifestations. Reactive oxygen species (ROS) are considered as key modulators in the development of PD. Despite the intensive investigations, antioxidant-dependent molecular mechanisms of initiation and development of PD are controversial. Free radicals cause serious damage and death of dopamine producing cells when antioxidant capacity of the cells is reduced against oxidative stress (OxS). Many intracellular reactions create ROS, including activation of NADPH oxidase (NOX), mitochondrial dysfunction, and hydrogen peroxide (H₂O₂) decomposition. On the contrary, natural antioxidants, vitamins, proteins, and antioxidant signaling pathways are major factors to neutralize ROS and its destructive effects. The functional role of nuclear factor E2-related factor 2, Heme oxygenase-1, and selenium against ROS-dependent initiation and progression of PD is elucidated. In this review, we collected multiple factors that play the main role in the initiation, development, and pathogenesis of PD and we discussed their function in the PD., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: Acute paracetamol (PCM) toxicity is a clinical problem; can result in a serious liver injury that finally may progress to acute liver failure. Curcumin (CUR) is a prevalent natural compound that can maintain prooxidant/antioxidant balance and thus can help in liver protection; also, Silymarin (SL) is a traditional antioxidant herb, used to treat liver disorders through scavenging free radicals. This study aimed to illustrate the histological, biochemical and molecular changes induced by acute PCM overdose on rats' liver to elucidate the effectiveness of CUR compared to SL in alleviating such changes., Materials and Methods: Male Wister Albino rats were divided into 6 groups each comprising 23 rats: control group, curcumin (CUR) treated group received (100 mg CUR/ kg), silymarin treated group received (100 mg SL/kg) for 7 successive days. Paracetamol (PCM) exposed group administered a single dose of PCM (200 mg/kg orally on 8th day). PCM + CUR group and PCM + SL group pretreated with CUR and SL respectively for 7 days then received single PCM dose (200 mg/kg) on the 8th day. Blood and liver tissues were collected for biochemical, histopathological and immunohistochemical analyses using anti-p53 antibody. In addition, real time polymerase chain reaction (RT- PCR) was used to measure Bax, bcl2 and Peroxisome proliferator-activated receptor-gamma (PPAR γ) mRNA expression levels., Results: In the paracetamol overdose group, the liver architecture showed necrotic changes, hydropic degeneration, congestion and dilatation of central veins. This hepatocellular damage was confirmed by a significant increase of AST, ALT levels and by an apparent increase in the number of p53 stained cells. PCM toxicity showed significant elevation of total oxidant status (TOS), oxidant status index (OSI) and decreased total antioxidant capacity (TAC) compared to controls (p < 0.001). Gene expression analysis showed that PCM caused an elevation of bcl2 and a reduction of both Bax and PPARγ mRNA expression. The histological alternation in the liver architecture was markedly improved in (PCM + CUR) group compared to (PCM+ SL) group, with an obvious decrease in the number of P53 stained cells. CUR pretreatment inhibited the elevation of TOS and OSI as well as the reduction of TAC caused by PCM toxicity compared to (PCM + SL) group., Conclusion: Both SL and CUR pretreatment prevented the toxic effects of PCM, but CUR is more effective than SL in ameliorating acute PCM induced hepatotoxicity., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background Modulatory effects of soy extract and estradiol on the central nervous system (CNS) have been reported. The effect of soy on scopolamine-induced spatial learning and memory in comparison to the effect of estradiol was investigated. Materials and methods Ovariectomized rats were divided into the following groups: (1) control, (2) scopolamine (Sco), (3) scopolamine-soy 20 (Sco-S 20), (4) scopolamine-soy 60 (Sco-S 60), (5) scopolamine-estradiol 20 (Sco-E 20) and (6) scopolamine-estradiol 60 (Sco-E 60). Soy extract, estradiol and vehicle were administered daily for 6 weeks before training in the Morris water maze (MWM) test. Scopolamine (2 mg/kg) was injected 30 min before training in the MWM test. Results In the MWM, the escape latency and traveled path to find the platform in the Sco group was prolonged compared to the control group (p < 0.001). Treatment by higher doses of soy improved performances of the rats in the MWM (p < 0.05 - p < 0.001). However, treatment with both doses of estradiol (20 and 60 μg/kg) resulted in a statistically significant improvement in the MWM (p < 0.01 - p < 0.001). Cortical, hippocampal and serum levels of malondialdehyde (MDA), as an index of lipid peroxidation, were increased which was prevented by soy extract and estradiol (p < 0.001). Cortical, hippocampal as well as serum levels of the total thiol, superoxide dismutase (SOD) and catalase (CAT) in Sco group were lower than the control group (p < 0.001) while they were enhanced when the animals were treated by soy extract and estradiol (p < 0.01 - p < 0.001). Conclusions It was observed that both soy extract and estradiol prevented learning and memory impairments induced by scopolamine in ovariectomized rats. These effects can be attributed to their protective effects on oxidative damage of the brain tissue.

Enzymatic cycling system (coupled dehydrogenase-catalyzed biosystem being composed of two elementary enzymatic reactions mediated by NAD(P)H + NAD(P) + ) is industrially attractive for reducing prochiral carbonyl compounds to the corresponding chiral hydroxyl compounds. The reaction rate equation of the batch-wise biosystem was generally derived by ordered Bi Bi mechanism of two-substrate enzyme reaction on several reasonable assumptions. The rate equations of the batch-wise biosystem was generalized by transforming them into the dimensionless forms. The dimensionless forms were solved numerically. It was revealed that the batch-wise biosystem was generally made up of unique 3 phases, i.e., phases I, II and III. Phase I was very short transient so that the biosystem entered rapidly phase II. In phase II the consumption rate dynamically balanced with its formation rate so that the concentration of NAD(P)H was invariable with time (and hence NAD(P) + concentration was, too). Phase III was substrate-exhausting phase, and the coenzyme concentration became finally only [NAD(P) + ] or only [NAD(P)H] depending on the initial molar ratio of the prochiral carbonyl compound to the substrate of the coenzyme regeneration reaction ( [Formula: see text] ) > or <1.0. In phases I and II the numerically calculated values of state variables were very close to the analytical but approximate ones. Preferable initial conditions of the batch-wise enzymatic cycling system, i.e., the initial coenzyme species = NAD(P) + and [Formula: see text] , were proposed. As the main assumption irreversibility of the two elemental enzymatic reactions was discussed. Validity of the proposed rate equations was mentioned., (Copyright © 2019 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Objective: Critical illnesses are a significant public health issue because of their high rate of mortality, the increasing use of the Intensive Care Units and the resulting healthcare cost that is about 80 billion of dollars per year. Their mortality is about 12% whereas sepsis mortality reaches 30-40%. The only instruments currently used against sepsis are early diagnosis and antibiotic therapies, but the mortality rate can also be decreased through an improvement of the patient's nutrition. The aim of this paper is to summarize the effects of vitamins A, B, C and E on the balance between pro-oxidants and anti-oxidants in the critical care setting to confirm "a beneficial care enhancing"., Materials and Methods: The peer-reviewed articles analyzed were selected from PubMed databases using the keywords "critical care", "intensive care", "critical illness", "sepsis", "nutritional deficiency", "vitamins", "oxidative stress", "infection", and "surgery". Among the 654 papers identified, 160 articles were selected after title and abstract examination, removal of duplicates and of the studies on pediatric population. Finally, only the 92 articles relating to vitamins A, C, E and the B complex were analyzed., Results: The use of vitamins decreased morbidity and mortality in perioperative period and critically ill patients, especially in ICU. Among the most encouraging results, we found that the use of vitamins, both as monotherapy and in vitamins combinations, play a crucial role in the redox balance. Vitamins, especially vitamins A, C, E and the B complex, could help prevent oxidative damage through the breakdown of the oxidizing chemical chain reaction., Conclusions: Even if the results of the studies are sometimes discordant or inconclusive, the current opinion is that the supplementation of one or more of these vitamins in critically ill patients may improve their clinical outcome, positively affecting the morbidity and the mortality. Further, randomized studies are required to deeply understand the potentiality of a vitamin supplementation therapy and develop homogeneous and standardized protocols to be adopted in every critical care scenario.

Organisms have evolved two different classes of the ubiquitous enzyme fumarase: the [4Fe-4S] cluster-containing class I enzymes are oxidant-sensitive, whereas the class II enzymes are iron-free and therefore oxidant-resistant. When hydrogen peroxide (H 2 O 2 ) attacks the most-studied [4Fe-4S] fumarases, only the cluster is damaged, and thus the cell can rapidly repair the enzyme. However, this study shows that when elevated levels of H 2 O 2 oxidized the class I fumarase of the obligate anaerobe Bacteroides thetaiotaomicron (Bt-Fum), a hydroxyl-like radical species was produced that caused irreversible covalent damage to the polypeptide. Unlike the fumarase of oxygen-tolerant bacteria, Bt-Fum lacks a key cysteine residue in the typical "CX n CX 2 C″ motif that ligands [4Fe-4S] clusters. Consequently H 2 O 2 can access and oxidize an iron atom other than the catalytic one in its cluster. Phylogenetic analysis showed that certain clades of bacteria may have evolved the full "CX n CX 2 C″ motif to shield the [4Fe-4S] cluster of fumarase. This effect was reproduced by the construction of a chimeric enzyme. These data demonstrate the irreversible oxidation of Fe-S cluster enzymes and may recapitulate evolutionary steps that occurred when microorganisms originally confronted oxidizing environments. It is also suggested that, if H 2 O 2 is generated within the colon as a consequence of inflammation or the action of lactic acid bacteria, the inactivation of fumarase could potentially impair the central fermentation pathway of Bacteroides species and contribute to gut dysbiosis., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)