Nitro-oxidative Stress Research Articles

Melatonin attenuates LPS-induced ovarian toxicity via modulation of SIRT-1, PI3K/pAkt, pErk1/2 and NFĸB/COX-2 expressions

The association between inflammation and metabolic disturbances leads to various female pathophysiological conditions. Bacterial lipopolysaccharide (LPS), found in the outer membrane of gram-negative bacteria, elicits an oxidative and inflammatory response that profoundly interferes with female reproductive health. We investigated the ameliorative action of melatonin on LPS-induced ovarian pathophysiology in golden hamsters, Mesocricetus auratus. Hamsters were administered with exogenous melatonin (5 mg/kg BW) and LPS (100 μg/kg BW) intraperitoneally for 7 days. LPS treatment impaired ovarian folliculogenesis as evident by histoarchitecture (elevated number of atretic follicles, reduced number of growing follicles and corpus luteum) and steroidogenesis (decreased aromatase/ERα, estradiol and progesterone). On the other hand, LPS administration also perturbed thyroid hormone (T3 and T4) homeostasis, ovarian melatonin receptor (MT-1) expression, antioxidant potential (SOD and catalase) and concomitantly elevated nitro-oxidative stress (decreased SOD, catalase and elevated CRP, TNFα and nitrate/nitrite level) and inflammatory load (NFĸB and COX-2) which culminated into ovarian follicular apoptosis (elevated caspase-3). LPS also disrupted metabolic homeostasis as indicated by hyperinsulinemia with a simultaneous decrease in ovarian IR/GLUT-4 and glucose content. Moreover, LPS treatment decreased expressions of key markers of ovarian physiology (SIRT-1, pErk1/2, PI3K and pAkt). Melatonin co-treatment with LPS improve these detrimental changes proposing melatonin as a potent therapeutic candidate against ovarian dysfunction induced by endotoxin.

Understanding the Role of Nitronate Monooxygenases in Virulence of the Human Fungal Pathogen Aspergillus fumigatus.

Aspergillus fumigatus is the leading cause of the fungal invasive disease called aspergillosis, which is associated with a high mortality rate that can reach 50% in some groups of immunocompromised individuals. The increasing prevalence of azole-resistant A. fumigatus isolates, both in clinical settings and the environment, highlights the importance of discovering new fungal virulence factors that can potentially become targets for novel antifungals. Nitronate monooxygenases (Nmos) represent potential targets for antifungal compounds as no orthologs of those enzymes are present in humans. Nmos catalyse the denitrification of nitroalkanes, thereby detoxifying these mediators of nitro-oxidative stress, and therefore we tested whether Nmos provide protection for A. fumigatus against host-imposed stresses at sites of infection. The results of inhibition zone assays indicated that Nmo2 and Nmo5 are not essential for the oxidative stress resistance of A. fumigatus in vitro. In addition, the resazurin-based metabolic activity assay revealed that the growth of mutants lacking the nmo2 or nmo5 genes was only slightly reduced in the presence of 0.05 mM peroxynitrite. Nevertheless, both Nmo2 and Nmo5 were shown to contribute to defense against murine bone marrow-derived macrophages, and this was no longer observed when NADPH oxidase, the main generator of reactive oxygen species during infection, was inhibited in macrophages. Furthermore, we revealed that Nnmos promote the virulence of the fungus in the Galleria mellonella model of infection. Both nmo2 and nmo5 knock-out strains were less virulent than the wild-type control as recorded 72 h post-infection. Our results indicate that Nmos play a role in the virulence of A. fumigatus.

Effect of the Human Amniotic Membrane on the Umbilical Vein Endothelial Cells of Gestational Diabetic Mothers: New Insight on Inflammation and Angiogenesis.

One of the most relevant diabetes complications is impaired wound healing, mainly characterized by reduced peripheral blood flow and diminished neovascularization together with increased inflammation and oxidative stress. Unfortunately, effective therapies are currently lacking. Recently, the amniotic membrane (AM) has shown promising results in wound management. Here, the potential role of AM on endothelial cells isolated from the umbilical cord vein of gestational diabetes-affected women (GD-HUVECs), has been investigated. Indeed, GD-HUVECs in vivo exposed to chronic hyperglycemia during pregnancy compared to control cells (C-HUVECs) have shown molecular modifications of cellular homeostasis ultimately impacting oxidative and nitro-oxidative stress, inflammatory phenotype, nitric oxide (NO) synthesis, and bioavailability, thus representing a useful model for studying the mechanisms potentially supporting the role of AM in chronic non-healing wounds. In this study, the anti-inflammatory properties of AM have been assessed using a monocyte–endothelium interaction assay in cells pre-stimulated with tumor necrosis factor-α (TNF-α) and through vascular adhesion molecule expression and membrane exposure, together with the AM impact on the nuclear factor kappa-light-chain-enhancer of activated B cell (NF-kB) pathway and NO bioavailability. Moreover, GD-HUVEC migration and tube formation ability were evaluated in the presence of AM. The results showed that AM significantly reduced TNF-α-stimulated monocyte–endothelium interaction and the membrane exposure of the endothelial vascular and intracellular adhesion molecules (VCAM-1 and ICAM-1, respectively) in both C- and GD-HUVECs. Strikingly, AM treatment significantly improved vessel formation in GD-HUVECs and cell migration in both C- and GD-HUVECs. These collective results suggest that AM positively affects various critical pathways in inflammation and angiogenesis, thus providing further validation for ongoing clinical trials in diabetic foot ulcers.

Sirtuin1 inhibitor attenuates hypertension in spontaneously hypertensive rats: role of Giα proteins and nitroxidative stress.

We recently showed that vascular smooth muscle cells (VSMCs) from spontaneously hypertensive rats (SHR) exhibit overexpression of Sirtuin1 (Sirt1) that contributes to the enhanced expression of Giα proteins implicated in the development of hypertension in SHR. The present study investigated if the inhibition of Sirt1 could also ameliorate hypertension in SHR and explore the underlying molecular mechanisms. For this study, a selective inhibitor of Sirt1, EX-527 (5 mg/kg of body weight), was injected intraperitoneally into 8-week-old SHR and age-matched Wistar Kyoto (WKY) rats twice per week for 3 weeks. The blood pressure (BP) and heart rate was measured twice a week by the CODA noninvasive tail cuff method. The high BP and augmented heart rate in SHR was significantly attenuated by EX-527 treatment, which was associated with the suppression of the overexpression of Sirt1 and Giα proteins in heart, VSMC and aorta. In addition, the enhanced levels of superoxide anion, NADPH oxidase activity, overexpression of NADPH oxidase subunits and FOXO1 were attenuated and the decreased levels of endothelial nitric oxide synthase (eNOS), nitric oxide and increased levels of peroxynitrite (ONOO-) and tyrosine nitration in VSMC from SHR were restored to control levels by EX-527 treatment. Furthermore, knockdown of FOXO1 by siRNA also attenuated the overexpression of Giα-2 and NADPH oxidase subunit proteins and restored the decreased expression of eNOS in VSMC from SHR. These results suggest that the inhibition of overexpressed Sirt1 and its target FOXO1 through decreasing the enhanced levels of Giα proteins and nitro-oxidative stress attenuates the high BP in SHR.

O-185 Cryopreservation of Human Spermatozoa: Utilization of L-Proline as a Novel Additive to Improve Sperm Quality Following Freezing-Thawing Process

Abstract Study question Does supplementation of human sperm freezing media with L-Proline improve sperm quality and DNA Integrity following the freezing-thawing process? Summary answer The inclusion of L-proline as a novel additive to human sperm cryopreservation media improves sperm parameters and DNA integrity via mitigating oxidative stress. What is known already Sperm cryopreservation is an essential aspect of assisted reproductive technique (ART) and male fertility preservation. Although frozen-thawed semen has great practical benefits for reproduction, it is widely reported that the cryopreservation process induces physical and chemical detrimental changes in sperm functions. Indeed, freezing induces nitro-oxidative stress, lipid peroxidation, DNA fragmentation, and apoptosis. L-proline plays versatile roles in osmotic protection and oxidative stress, cell signaling, programmed cell death, and nutrient adaptation. This multifunctional amino acid is a natural osmoprotectant and the protective effect of L-proline against freezing-thawing-induced damages in stallion and donkey spermatozoa have been reported. Study design, size, duration Thirty normozoospermic semen samples were collected by masturbation after 3–5 days of sexual abstinence from men who were referred to the IVF clinic of Kermanshah Motazedi Hospital from December 2020 to June 2021. Each prepared semen sample was aliquoted to 4. In aliquots 1 to 4, experimental concentrations of L-proline (0, 1, 2, and 4 mmol/L), were included in the freezing medium. Participants/materials, setting, methods 30 normozoospermic, healthy, non-smoker men were enrolled. Sperm parameters (progressive motility, viability, and morphology) were assessed. Sperm chromatin quality was measured by Aniline blue (AB), Toluidine blue (TB), and Chromomycin A3 (CMA3) staining. DNA integrity was evaluated by the Sperm chromatin dispersion (SCD) test. Furthermore, the levels of reactive oxygen species (ROS), lipid peroxidation (LPO), and total antioxidant capacity (TAC) were determined in sperm freezing media. All assessments were conducted before cryopreservation and after thawing. Main results and the role of chance Our findings showed that sperm progressive motility and viability were significantly higher in the 4 mmol/L L-proline treated groups compared to the control groups (p = 0.003, p = 0.0200) respectively. The percentage of normal morphology was improved in L-Proline-treated groups. However, this improvement was not considerable (p > 0.5). Moreover, the level of ROS production significantly diminished in the 4 mmol/L L-proline group compared to the control group (p < 0.001). Besides, the level of TAC was significantly enhanced in the 4 mmol/L L-proline group by comparison to the control group (p < 0.001). Furthermore, the results of AB and TB tests demonstrated that chromatin packaging after supplementation with 4 mmol/L L-proline significantly improved compared to the control group (p < .0001). In this regard, there was a significant improvement between the 4 mmol/L L-proline group and the control group in terms of CMA3 evaluation (p < .0001). Also, there was a difference between the 4 mmol/L L-proline group and the control group in reducing the level of fragmented DNA. Although 4 mmol/L of Praline could diminish the SCD level compared to the control group, this amelioration was not statically significant (p = 0.053). Limitations, reasons for caution We were not able to perform further studies to verify the effects of L-proline on mitochondrial activity and membrane potential, and sperm apoptosis as well as to confirm the efficiency and safety of L-proline in terms of more indicators such as the in vitro embryonic development and live birth rate. Wider implications of the findings These findings can draw attention to the potential role of L-proline as a novel additive and antioxidant to human freezing medium in preserving sperm quality and protecting spermatozoa against ROS attack during sperm cryopreservation in infertility clinics. Trial registration number N/A

P-303 Supplementing IVM medium with mesenchymal stem cell-conditioned medium, L-carnitine, and Repaglinide to improve maturation and developmental competence of oocytes derived from normal and endometriosis mice

Abstract Study question Does supplementing in vitro maturation (IVM) medium with bone marrow mesenchymal stem cell-conditioned medium (BMSC-CM), L-carnitine (LC), and Repaglinide (RG) enhance the developmental competence of oocytes derived from endometriosis-induced mice? Summary answer L-carnitine and BMSC-CM supplementation improved maturation and fertilization, and developmental competence of oocytes following IVF by modulating nitro-oxidative stress and accelerating nuclear maturation of oocytes. What is known already Endometriosis (EMS) is a detrimental condition of the female reproductive system affecting up to 15% of women of reproductive age. Oocytes retrieved from EMS-affected ovaries are more likely to fail IVM and to show altered morphology and lower cytoplasmic mitochondrial content. Mesenchymal stem cells (MSCs) secrete various types of cytokines, growth factors, bioactive factors, and tissue regenerative components into mesenchymal stem cell-conditioned medium. L-carnitine is an antioxidant playing an important role in cell metabolism and is crucial for fatty acid metabolism. Repaglinide (RG) is an anti-hyperglycemic medication that induces insulin secretion by attaching to β cells of the pancreas. Study design, size, duration To induce EMS, two groups of mice were used. The first group, as donor mice, were intraperitoneally injected with estradiol-17β depot for one week. Then, they were sacrificed on day 14, and their uterine horns were removed. The suspension including tissue fragments from uterine horns was injected intraperitoneally to the recipient mice group. To ensure the induction of EMS, ovaries of some mice in both normal and EMS groups were analyzed by histological examination. Participants/materials, setting, methods Adult female NMRI mice (6-8 weeks old) were divided into two normal and EMS-induced mice. Oocytes obtained from normal and EMS-induced mice were cultured in the IVM medium supplemented with RG, LC, and BMSC-CM for 24 hours. Subsequently, IVM, IVF, embryo development rates, blastocyst cell numbers were assessed. Moreover, the levels of reactive oxygen species (ROS), nitric oxide (NO), and total antioxidant capacity (TAC) of the IVM medium were evaluated. Main results and the role of chance Microscopic studies of ovarian tissue samples showed that folliculogenesis, quality of follicles, and oocyte quality reduced in the EMS-induced group. The IVM results represent that 0.3 mg/ml and 0.6 mg/ml of LC, and 25% and 50% of BMSC-CM enhanced the percentage of MII oocytes significantly. Indeed, the highest IVM rate in both the normal and EMS-induced mice was observed in the BMSC-CM 50% group. More importantly, 0.3 and 0.6 mg/ml of LC, and 25% and 50% of BMSC-CM treatments showed a dramatic decrease in ROS and NO levels and a significant enhancement in TAC levels compared to the control group. Our results also indicated that there was a substantial improvement in terms of IVF, cleavage, and blastocyst rates in all treatment groups compared to the control group. The highest blastocyst formation rate was obtained in 50% of the BMSC-CM group. In normal groups, there was a dramatic increase in the mean of total cell number and TE cells in 1µM RG, 0.3 and 0.6 mg/ml LC, 25% and 50% BMSC-CM. In EMS-induced groups, except for the 1M RG group, all treatment groups exhibited a significant difference in the mean total cell population and TE cells compared to the control group. Limitations, reasons for caution Due to limited laboratory facilities, the levels of growth factors, pro-inflammatory cytokines, anti-apoptotic, and antioxidants were not measured in the IVM medium. We, therefore, do not know which of the constituents of the BMSC-CM, in particular, had promoter effects on the oocyte maturation, fertilization, and developmental competence of IVF embryos. Wider implications of the findings These approaches may outline the clinical applications of LC and BMSC-CM in the assisted reproductive technology (ART) setting and pave the way to improve the maturation culture. Also, these findings can advance the efficiency of fertility outcomes in endometriosis-related infertile couples. Trial registration number N/A

The Role of Alternative Oxidase in the Interplay between Nitric Oxide, Reactive Oxygen Species, and Ethylene in Tobacco (Nicotiana tabacum L.) Plants Incubated under Normoxic and Hypoxic Conditions.

The transgenic tobacco (Nicotiana tabacum L.) plants with the modified levels of alternative oxidase (AOX) were used to evaluate the physiological roles of AOX in regulating nitro-oxidative stress and metabolic changes after exposing plants to hypoxia for 6 h. Under normoxia, AOX expression resulted in the decrease of nitric oxide (NO) levels and of the rate of protein S-nitrosylation, while under hypoxia, AOX overexpressors exhibited higher NO and S-nitrosylation levels than knockdowns. AOX expression was essential in avoiding hypoxia-induced superoxide and H2O2 levels, and this was achieved via higher activities of catalase and glutathione reductase and the reduced expression of respiratory burst oxidase homolog (Rboh) in overexpressors as compared to knockdowns. The AOX overexpressing lines accumulated less pyruvate and exhibited the increased transcript and activity levels of pyruvate decarboxylase and alcohol dehydrogenase under hypoxia. This suggests that AOX contributes to the energy state of hypoxic tissues by stimulating the increase of pyruvate flow into fermentation pathways. Ethylene biosynthesis genes encoding 1-aminocyclopropane-1-carboxylic acid (ACC) synthase, ACC oxidase, and ethylene-responsive factors (ERFs) were induced during hypoxia and correlated with AOX and NO levels. We conclude that AOX controls the interaction of NO, reactive oxygen species, and ethylene, triggering a coordinated downstream defensive response against hypoxia.

Experimental Models of Ischemic Lung Damage for the Study of Therapeutic Reconditioning During Ex Vivo Lung Perfusion.

Background.Ex vivo lung perfusion (EVLP) may allow therapeutic reconditioning of damaged lung grafts before transplantation. This study aimed to develop relevant rat models of lung damage to study EVLP therapeutic reconditioning for possible translational applications.Methods.Lungs from 31 rats were exposed to cold ischemia (CI) or warm ischemia (WI), inflated at various oxygen fractions (FiO2), followed by 3 h EVLP. Five groups were studied as follow: (1) C21 (control): 3 h CI (FiO2 0.21); (2) C50: 3 h CI (FiO2 0.5); (3) W21: 1 h WI, followed by 2 h CI (FiO2 0.21); (4) W50: 1 h WI, followed by 2 h CI (FiO2 0.5); and (5) W2h: 2 h WI, followed by 1 h CI (FiO2 0.21). Following 3 h EVLP, we measured static pulmonary compliance (SPC), pulmonary vascular resistance, lung weight gain (edema), oxygenation capacity (differential partial pressure of oxygen), and protein carbonyls in lung tissue (oxidative stress), as well as lactate dehydrogenase (LDH, lung injury), nitrotyrosine (nitro-oxidative stress), interleukin-6 (IL-6, inflammation), and proteins (permeability edema) in bronchoalveolar lavage (BAL). Perivascular edema was quantified by histology.Results.No significant alterations were noted in C21 and C50 groups. W21 and W50 groups had reduced SPC and disclosed increased weight gain, BAL proteins, nitrotyrosine, and LDH. These changes were more severe in the W50 group, which also displayed greater oxidative stress. In contrast, both W21 and W50 showed comparable perivascular edema and BAL IL-6. In comparison with the other WI groups, W2h showed major weight gain, perivascular edema, SPC reduction, drop of differential partial pressure of oxygen, and massive increases of BAL LDH and proteins but comparable increase of IL-6 and biomarkers of oxidative stress.Conclusions.These models of lung damage of increasing severity might be helpful to evaluate new strategies for EVLP therapeutic reconditioning. A model combining 1 h WI and inflation at FiO2 of 0.5 seems best suited for this purpose by reproducing major alterations of clinical lung ischemia-reperfusion injury.

Candesartan Effectively Preserves Cognition in Senescence Accelerated Mouse Prone 8 (SAMP8) mice.

Background:Alzheimer’s disease (AD) has become a worldwide crisis with no effective therapeutic options. The medications currently available for AD are only palliative; their effect is temporary, and they are associated with unfavorable side effects. Even the newest medication aducanumab, granted accelerated FDA approval in 2021, failed to show cognitive benefits in clinical trials and continued approval requires verification in subsequent clinical trials. There is an urgent need for safe and effective therapies to preserve cognition and effectively manage AD. Generally, a new drug product takes several years for FDA approval and exceeds 2.5 billion dollars in research and development, with most new drug products never even reaching the market. This has led to a recent shift for repurposing/repositioning existing FDA-approved medications, to new therapeutic indications.Objective:To investigate the effects of long-term treatment with candesartan, an FDA-approved angiotensin-II type-1 receptor blocker (ARB), on the development of cognitive impairment associated with premature aging.Methods:Candesartan was given at a dose of 1 mg/kg/d in an AD model of senescence-accelerated mouse prone-8 (SAMP8) and senescence-accelerated mouse resistant (SAMR1) mice. Oral treatment with candesartan or vehicle was started, in 2-month-old mice and administered continuously for 4-months.Results:Low-dose candesartan prevented the development of cognitive impairment, otherwise associated with accelerated aging, in SAMP8 mice, by reducing inflammation and nitro-oxidative stress. Candesartan did not affect the cognitive function of control SAMR1 mice.Conclusion:Early ARB treatment might be beneficial in preventing age-related cognitive deficits in AD-prone individuals.

Arterial graft preservation with an endothelial damage inhibitor reduces vascular dysfunction in a rat model of in vitro ischemia/reperfusion injury

Coronary artery bypass grafting (CABG) with autologous conduits is a common surgical operation to redirect blood flow to the ischemic myocardium. Vascular ischemia/reperfusion injury (IR) occurs during graft harvest and implantation, and can lead to endothelial dysfunction. DuraGraft®, a novel one-time intraoperative vascular graft treatment, has been shown to protect integrity and function in saphenous vein grafts against IRI. We compared the effect of DuraGraft® to saline solution on arterial grafts submitted to IRI. Rat thoracic aorta was harvested, prepared, and immediately mounted in organ bath chambers (control, n = 7 rats) or underwent 24-hour cold ischemic preservation (4 °C) either in physiological saline (IR, n = 9 rats) or DuraGraft® (IR + Dura, n = 9 rats). Reperfusion-associated endothelial injury was simulated by hypochlorite. Vascular function was measured ex vivo and immunohistochemistry was performed. Impaired maximal vasorelaxation (Rmax) to acetylcholine (ACh) in the IR-group compared to controls was ameliorated by DuraGraft®, indicating an improvement in endothelial function (Rmax to ACh (%): IR + Dura 73 ± 2 vs. IR 48 ± 3, P < 0.05). Additionally, decreased aortic ring sensitivity to ACh (pD2-value: -log 50% maximum response) seen after IR in the saline group was increased by DuraGraft® (pD2 to ACh: IR + Dura 7.1 ± 0.1 vs. IR 6.3 ± 0.2, P < 0.05). Impaired maximum contractile response to phenylephrine and high K+-induced depolarization in the IR-group compared to controls was improved by DuraGraft®. Immunohistochemical analysis for ICAM-1 showed positivity confined to the endothelial layer in the IR group compared to controls, which was decreased by the preservation of aortic rings with DuraGraft®. Furthermore, DuraGraft® decreased nitrotyrosine immunoreactivity in the IR + DuraGraft® compared to both control and IR groups. Also, endothelial PECAM-1 immunoreactivity was significantly reduced in the IR rings compared to controls, whereas a similar pattern was observed between control and IR + Duragraft® groups. DuraGraft® alleviates vascular dysfunction following in vitro IR injury, in part, by reducing nitro-oxidative stress and by lowering inflammatory response through ICAM-1.

False dogmas in mood disorders research: Towards a nomothetic network approach.

The current understanding of major depressive disorder (MDD) and bipolar disorder (BD) is plagued by a cacophony of controversies as evidenced by competing schools to understand MDD/BD. The DSM/ICD taxonomies have cemented their status as the gold standard for diagnosing MDD/BD. The aim of this review is to discuss the false dogmas that reign in current MDD/BD research with respect to the new, data-driven, machine learning method to model psychiatric illness, namely nomothetic network psychiatry (NNP). This review discusses many false dogmas including: MDD/BD are mind-brain disorders that are best conceptualized using a bio-psycho-social model or mind-brain interactions; mood disorders due to medical disease are attributable to psychosocial stress or chemical imbalances; DSM/ICD are the gold standards to make the MDD/BD diagnosis; severity of illness should be measured using rating scales; clinical remission should be defined using threshold values on rating scale scores; existing diagnostic BD boundaries are too restrictive; and mood disorder spectra are the rule. In contrast, our NNP models show that MDD/BD are not mind-brain or psycho-social but systemic medical disorders; the DSM/ICD taxonomies are counterproductive; a shared core, namely the reoccurrence of illness (ROI), underpins the intertwined recurrence of depressive and manic episodes and suicidal behaviors; mood disorders should be ROI-defined; ROI mediates the effects of nitro-oxidative stress pathways and early lifetime trauma on the phenome of mood disorders; severity of illness and treatment response should be delineated using the NNP-derived causome, pathway, ROI and integrated phenome scores; and MDD and BD are the same illness.

Inflammation and Nitro-oxidative Stress as Drivers of Endocannabinoid System Aberrations in Mood Disorders and Schizophrenia.

The endocannabinoid system (ECS) is composed of the endocannabinoid ligands anandamide (AEA) and 2-arachidonoylgycerol (2-AG), their target cannabinoid receptors (CB1 and CB2) and the enzymes involved in their synthesis and metabolism (N-acyltransferase and fatty acid amide hydrolase (FAAH) in the case of AEA and diacylglycerol lipase (DAGL) and monoacylglycerol lipase (MAGL) in the case of 2-AG). The origins of ECS dysfunction in major neuropsychiatric disorders remain to be determined, and this paper explores the possibility that they may be associated with chronically increased nitro-oxidative stress and activated immune-inflammatory pathways, and it examines the mechanisms which might be involved. Inflammation and nitro-oxidative stress are associated with both increased CB1 expression, via increased activity of the NADPH oxidases NOX4 and NOX1, and increased CNR1 expression and DNA methylation; and CB2 upregulation via increased pro-inflammatory cytokine levels, binding of the transcription factor Nrf2 to an antioxidant response element in the CNR2 promoter region and the action of miR-139. CB1 and CB2 have antagonistic effects on redox signalling, which may result from a miRNA-enabled negative feedback loop. The effects of inflammation and oxidative stress are detailed in respect of AEA and 2-AG levels, via effects on calcium homeostasis and phospholipase A2 activity; on FAAH activity, via nitrosylation/nitration of functional cysteine and/or tyrosine residues; and on 2-AG activity via effects on MGLL expression and MAGL. Finally, based on these detailed molecular neurobiological mechanisms, it is suggested that cannabidiol and dimethyl fumarate may have therapeutic potential for major depressive disorder, bipolar disorder and schizophrenia.

S-nitrosoglutathione alleviates hyperglycemia-induced neurobehavioral deficits involving nitro-oxidative stress and aberrant monaminergic system

The present study evaluated the protective role of S-nitrosoglutathione (GSNO) in preventing hyperglycemia-induced nitro-oxidative stress and alterations in monoaminergic system associated with neurobehavioral deficits in mice. Mice were subjected to diabetes by intraperitoneal injection of streptozotocin (40 mg/kg body weight) for 5 days, whereas GSNO (100 μg/kg body weight) was administered daily via oral route for 8 weeks. Diabetic mice showed deficits in neurobehavioral functions associated with memory, learning, anxiety and motor coordination. These neurobehavioral deficits observed in diabetic mice may be attributed to decrease in norepinephrine (NE), dopamine (DA), serotonin (5-HT) and increased monoamine oxidase (MAO) activity in cortex and hippocampus. Further, a significant increase in reactive oxygen species (ROS), protein carbonyls, nitrotyrosine (NT) and lipid peroxidation were observed in brain regions of diabetic animals suggesting increased nitro-oxidative stress. Hyperglycemia induced nitro-oxidative stress appears to involve reduction in redox ratio (GSH/GSSG) and enzymatic antioxidants; catalase (CAT) and superoxide dismutase (SOD) in cortex and hippocampus. However, GSNO supplementation was able to ameliorate alterations in monoaminergic system and nitro-oxidative stress in the brain regions thereby restoring neurobehavioural functions. These findings suggest GSNO as potential therapeutic molecule to prevent diabetic encephalopathy.

Alternative oxidase plays a role in minimizing ROS and RNS produced under salinity stress in Arabidopsis thaliana.

Under stress conditions, the overproduction of different reactive oxygen species (ROS) and reactive nitrogen species (RNS) causes imbalance in the redox homeostasis of the cell leading to nitro-oxidative stress in plants. Alternative oxidase (AOX) is a conserving terminal oxidase of the mitochondrial electron transport chain, which can minimize the ROS. Still, the role of AOX in the regulation of RNS during nitro-oxidative stress imposed by salinity stress is not known. Here, we investigated the role of AOX in minimizing ROS and RNS induced by 150 mM NaCl in Arabidopsis using transgenic plants overexpressing (AOX OE) and antisense lines (AOX AS) of AOX. Imposing NaCl treatment leads to a 4-fold enhanced expression of AOX accompanied by enhanced AOX capacity in WT Col-0. Further AOX-OE seedlings displayed enhanced growth compared with the AOX-AS line under stress. Examination of NO levels by DAF-FM fluorescence and chemiluminescence revealed that AOX overexpression leads to reduced levels of NO. The total NR activity was elevated under NaCl, but no significant change was observed in wild-type (WT), AOX OE, and AS lines. The total ROS, superoxide, H2 O2 levels, and lipid peroxidation were higher in the AOX-AS line than in WT and AOX-OE lines. The peroxynitrite levels were also higher in the AOX-AS line than in WT and AOX-OE lines; further, the expression of antioxidant genes was elevated in AOX-AS. Taken together, our results suggest that AOX plays an important role in the mitigation of ROS and RNS levels and enhances plant growth, thus providing tolerance against nitro-oxidative stress exerted by NaCl.

Protective Effect of Liposomal Epigallocatechin-Gallate in Experimental Gentamicin-Induced Hepatotoxicity.

Our study aimed to assess the effect of liposomal epigallocatechin-gallate (LEGCG) compared with epigallocatechin-gallate (EGCG) solution on hepatic toxicity induced by gentamicin (G) administration in rats. Five groups were evaluated, a control group (no G administration) and four groups that received G (1 mL, i.p, 80 mg/kg b.w. (body weight/day), for 7 days) to which we associated daily administration 30 min before G of EGCG (G-EGCG, 2.5 mg/0.1 kg b.w.), LEGCG (G-LEGCG, 2.5 mg/0.1 kg b.w.) or silymarin (100 mg/kg b.w./day). The nitro-oxidative stress (NOx), catalase (CAT), TNF-α, transaminases, creatinine, urea, metalloproteinase (MMP) 2 and 9, and liver histopathological changes were evaluated. LEGCG exhibited better efficacy than EGCG, improving the oxidant/antioxidant balance (p = 0.0125 for NOx and 0.0032 for CAT), TNF-α (p < 0.0001), MMP-2 (p < 0.0001), aminotransferases (p = 0.0001 for AST and 0.0136 for ALT), creatinine (p < 0.0001), urea (p = 0.0006) and histopathologic liver changes induced by gentamicin. Our study demonstrated the beneficial effect of EGCG with superior results of the liposomal formulation for hepatoprotection in experimental hepatic toxicity induced by gentamicin.

Markers of Carotid Plaque Destabilization in Patients With Sleep-Disordered Breathing.

Sleep-disordered breathing (SDB) is a nightly respiratory condition characterized by intermittent hypoxia, leading to oxidative stress, inflammation, and atherosclerosis. However, most cellular markers of human carotid plaques in SDB have not yet been assessed. We aimed at characterizing the cellular, inflammatory, and nitro-oxidative stress markers in carotid plaques obtained from 25 patients undergoing endarterectomy and screened for SDB. Sleep studies were performed during their preoperative hospitalization night using the Watch-PAT 100 device. Oxygen desaturation index (ODI) was used for dividing patients into two groups. Fourteen patients with ODI >5 were designated as SDB and 11 patients with ODI ≤ 5 as non-SDB. Demographics, comorbidities, cardiovascular risk factors, and medications were recorded. Cellular markers in plaques were analyzed by immunofluorescence using confocal microscopy. The expression of neutrophils was identified by CD66b+ and neutrophil elastase, macrophage-foam cells were identified by CD163+, and scavenger receptors by CD68+ and CD36+ expression. Additional markers included 3-nitrotyrosine, endothelial CD31, and smooth muscle cell-actin (SMC-actin). Plaques' lipids were determined by immunohistochemistry with Oil Red O staining. Notably, significantly higher values were found for SDB as compared to patients with non-SDB for 3-nitrotyrosine (p <0.004) and intracellular lipids' content (p <0.02), whereas SMC-actin was lower (p <0.006). There were no significant differences between patients with carotid-associated symptoms (symptomatic) and patients without carotid-associated symptoms (asymptomatic). However, a sub-group of symptomatic patients with co-existent SDB expressed the highest 3-nitrotyrosin, and intracellular lipids levels, and the lowest SMC-actin levels, whereas non-SDB/asymptomatic patients expressed the lowest 3-nitrotyrosin and lipids levels and the highest SMS-actin levels among all patients. Accordingly, ODI was lowest in non-SDB/asymptomatic patients and highest in SDB/symptomatic. In conclusion, plaques of patients with SDB were characterized by markedly increased levels of 3-nitrotyrosine and intracellular lipids content. Conversely, SMC-actin levels were significantly lower. These three markers, such as increased 3-nitrotyrosine and intracellular lipids and decreased SMC-actin are associated with plaque vulnerability and instability. These findings are in line with earlier reports demonstrating increased intima-media thickness in large cohorts of sleep apnea and patients with SDB, and thus, may indicate a higher susceptibility to plaque vulnerability and rapture in patients with SDB.

Aspirin Reduces Ischemia-Reperfusion Injury Induced Endothelial Cell Damage of Arterial Grafts in a Rodent Model.

Long-term graft patency determines the prognosis of revascularization after coronary artery bypass grafting (CABG). Ischemia-reperfusion (I/R) injury of the graft suffered during harvesting and after implantation might influence graft patency. Aspirin, a nonsteroidal anti-inflammatory drug improves the long-term patency of vein grafts. Whether aspirin has the same effect on arterial grafts is questionable. We aimed to characterize the beneficial effects of aspirin on arterial bypass grafts in a rodent revascularization model. We gave Lewis rats oral pretreatment of either aspirin (n = 8) or saline (n = 8) for 5 days, then aortic arches were explanted and stored in cold preservation solution. The third group (n = 8) was a non-ischemia-reperfusion control. Afterwards the aortic arches were implanted into the abdominal aorta of recipient rats followed by 2 h of reperfusion. Endothelium-dependent vasorelaxation was examined with organ bath experiments. Immunohistochemical staining were carried out. Endothelium-dependent maximal vasorelaxation improved, nitro-oxidative stress and cell apoptosis decreased, and significant endothelial protection was shown in the aspirin preconditioned group, compared to the transplanted control group. Significantly improved endothelial function and reduced I/R injury induced structural damage were observed in free arterial grafts after oral administration of aspirin. Aspirin preconditioning before elective CABG might be beneficial on free arterial graft patency.

Indium induces nitro-oxidative stress in roots of wheat (Triticum aestivum)

The entrance of indium, an emerging contaminant from electronics, into the agroecosystem inevitably causes its accumulation in crops and raises exposure risk of humans via food chain. This study investigated indium uptake and toxicological effects in wheat plants under a worst-case scenario. Inhibition of root growth is a primary manifestation of indium toxicity and most absorbed indium accumulated in wheat roots with only a tiny portion reaching the leaves. The enhancement of reactive oxygen species (ROS), lipid peroxidation and protein oxidation in roots suggest that indium caused oxidative stress. Additionally, we found the levels of nitric oxide and peroxyinitrite, two major reactive nitrogen species (RNS), also increased in wheat roots under indium stress. These changes were accompanied by a raise in protein tyrosine nitration, thereby provoking nitrosative stress. The increase in peroxyinitrite and S-nitrosoglutathione content, S-nitrosoglutathione reductase activity as well as a concomitant reduction in glutathione concentrations suggest a rigorous metabolic interplay between ROS and RNS. Moreover, indium simultaneously triggered alteration in protein carbonylation and nitration. Overall, our results suggest that indium induced nitro-oxidative stress which probably contributes to toxicological effects in wheat plants, which are helpful in reducing the potential risk from emerging contaminants analogous to indium to humans.

Inflammation and nitro-oxidative stress in current suicidal attempts and current suicidal ideation: a systematic review and meta-analysis.

A meta-analysis showed a significant association between activated immune-inflammatory and nitro-oxidative (IO&NS) pathways and suicide attempts (SA). There is no data on whether recent suicidal ideation (SI) is accompanied by activated IO&NS pathways and whether there are differences between recent SA and SI. The current study searched PubMed, Google Scholar, and Web of Science, for articles published from inception until May 10, 2021, and systematically reviewed and meta-analysed the association between recent SA/SI (<3 months) and IO&NS biomarkers. We included studies which compared psychiatric patients with and without SA and SI and controls (either healthy controls or patients without SA/SI) and used meta-analysis (random-effect model with restricted maximum-likelihood) to delineate effect sizes with 95% confidence intervals (CI). Our search included 59 studies comprising 4.034 SA/SI cases and 12.377 controls. Patients with SA/SI showed activated IO&NS pathways (SMD: 0.299; CI: 0.200; 0.397) when compared to controls. The immune profiles were more strongly associated with SA than with SI, particularly when compared to healthy controls, as evidenced by activated IO&NS (SMD: 0.796; CI: 0.503; 1.089), immune (SMD: 1.409; CI: 0.637; 1.462), inflammatory (SMD: 1.200; CI: 0.584; 1.816), and neurotoxic (SMD: 0.904; CI: 0.431; 1.378) pathways. The effects sizes of the IO&NS, immune and inflammatory profiles were significantly greater in SA than in SI. In conclusion: activated IO&NS pathways are associated with recent SA and SI, and inflammation, T helper-1 activation, nitro-oxidative stress, lowered neuroprotection, and increased neurotoxicity explain at least in part why psychiatric patients show increased suicidal behaviours, especially SA.

BIOFLAVONOIDS AS AGENTS FOR CORRECTING NITRO-OXIDATIVE STRESS AND SALIVARY GLAND FUNCTIONS IN RATS EXPOSED TO ALCOHOL DURING MODELED LIPOPOLYSACCHARIDE-INDUCED SYSTEMIC INFLAMMATORY RESPONSE

The aim: To investigate the effects of bioflavonoids (curcumin, epigallocatechin-3-gallate and quercetin) on nitro-oxidative stress and the functions of submandibular SGs in rats under alcohol exposure during SIR. Materials and methods: The studies were conducted on 35 rats of the Wistar line weighing 205-220 g, divided into 5 groups of seven animals in each: the 1st group, control group I, included animals receiving isotonic sodium chloride solution intragastrically twice a day; the 2nd group, control group II, included rats exposed to alcohol (in a dose of 24 mg/kg intragastrically through gavage a twice a day) for last 2 weeks during lipopolysaccharide (LPS)-induced SIR; the rats of the 3rd, 4th and 5th groups exposed to alcohol during LPS-induced SIR, which also received bioflavonoids. The bioflavonoids (“Sigma-Aldrich, Inc.”, USA) were as following: curcumin (in a daily dose of 200 mg/kg), epigallocatechin-3-gallate (in a daily dose of 40 mg/kg), and quercetin (in a daily dose of 200 mg/kg), respectively. SIR was induced by intraperitoneal administration of Salmonella typhi LPS (during the first week a dose of 0.4 μg/kg of body weight was administered 3 times a week; during the next 7 weeks of the experiment rats received 0.4 μg/kg of body weight once a week. The formation of superoxide anion radical (О2 -), activity of NO-synthase – total (NOS), its constitutive and inducible isoforms (cNOS, iNOS), and concentration of peroxynitrites and S-nitrosothiols were evaluated spectrophotometrically. To assess the functional status of submandibular SGs in their homogenate we determined α-amylase activity (spectrophotometrically) and the aquaporin-5 concentration (by enzyme-linked immunosorbent assay). through gav-age with orogastric cannul. Results: When applying bioflavonoids under the conditions of alcohol administration during SIR, NADH-induced .О2 - production decreased and yielded to the result in the control group II by 36.8% under administering curcumin, by 34.5% under administering epigallocatechin-3-gallate, and by 41.3% under administering quercetin. The total NOS activity in SGs tissues was inferior by 42.8% to the relevant data in the control group II (under curcumin administration), by 33.7% (under epigallocatechin-3-gallate administration) and by 46.6% (under quercetin administration); and the iNOS activity decreased by 47.0, 38.3 and 52.0%, respectively. Under the administration of bioflavonoids peroxynitrites concentration in the submandibular SGs tissues was inferior to the control group II by 35.6% (under curcumin administration), by 37.4% (under epigallocatechin-3-gallate administration), and by 39.3% (under quercetin administration); the content of S-nitrosothiols was lower by 34.5, 31.1 and 35.3%, respectively. The administration of bioflavonoids led to the changes in α-amylase activity in the submandibular SGs tissues: its values exceeded the relevant data in the control group II by 40.4% (under curcumin administration), by 38.2% (under epigallocatechin-3-gallate administration), and by 34.1% (under quercetin administration); under those conditions aquaporin-5 concentration grew in 2.66, 2.61 and 2.55 times, respectively. Conclusions: The use of bioflavonoids (curcumin, epigallocatechin-3-gallate, and quercetin) under the combined administration of 40% ethanol solution and LPS considerably limits the development of nitro-oxidative stress in the tissues of the submandibular SGs. The administration of the bioflavonoids increases the level of cNOS coupling, and improves the functional status of the submandibular SGs under the combined administration of alcohol and LPS enhancing the activity of α-amylase and concentration of aquaporin-5.