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Eosinophilic esophagitis (EoE) and gastroesophageal reflux disease (GERD) share many histopathological features; therefore, markers for differentiation are of diagnostic interest and may add to the understanding of the underlying mechanisms. The nitrergic system is upregulated in GERD and probably also in EoE. Esophageal biopsies of patients with EoE (n  = 20), GERD (n  = 20), and healthy volunteers (HVs) (n  = 15) were exposed to antibodies against inducible nitric oxide synthase (iNOS), nitrotyrosine, eosinophilic peroxidase, eotaxin-3, and galectin-3. The stained object glasses were randomized, digitized, and blindly analyzed regarding the expression of DAB (3,3′-diaminobenzidine) by a protocol developed in QuPath software. A statistically significant overexpression of iNOS was observed in patients with any of the two inflammatory diseases compared with that in HVs. Eotaxin-3 could differentiate HVs versus inflammatory states. Gastroesophageal reflux patients displayed the highest levels of nitrotyrosine. Neither iNOS nor nitrotyrosine alone were able to differentiate between the two diseases. For that purpose, eosinophil peroxidase was a better candidate, as the mean levels increased stepwise from HVs via GERD to EoE. iNOS and nitrotyrosine are significantly overexpressed in patients with EoE and GERD compared with healthy controls, but only eosinophil peroxidase could differentiate the two types of esophagitis. The implications of the finding of the highest levels of nitrotyrosine among gastroesophageal reflux patients are discussed. [ABSTRACT FROM AUTHOR]

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The aim of the research is to determine the clinical-pathogenetic and prognostic value of nitrotyrosine levels in the blood serum of patients with COVID-19 with pneumonia in the development of oxygen dependence and the risk of fatal outcome. Materials and methods. 123 patients with COVID-19 with pneumonia were examined, who were examined and treated according to the Order of the Ministry of Health of Ukraine dated March 28, 2020 No. 722. Patients were divided into groups: I group – 32 patients with a moderate course without oxygen dependence; II group – 91 patients with a severe course with the presence of oxygen dependence. Patients in the II group were additionally divided into subgroups: II-A subgroup – 45 patients who recovered; II-B subgroup – 46 patients who died. The content of nitrotyrosine (Hycult Biotech, the Netherlands) was determined in the blood serum by the immunoenzymatic method. Statistical data processing was carried out in the program Statistica for Windows 13 (StatSoft Inc., No. JPZ804I382130ARCN10-J). Results. The content of nitrotyrosine in the blood serum of patients with COVID-19 with pneumonia in a severe course with the development of oxygen dependence is higher (p < 0.001) than in patients with a moderate course of the disease without signs of oxygen dependence. The level of its increase has an inverse correlation with the oxygen saturation index (r = -0.53, р < 0.05). When hospitalized for 9.0 [7.0; 12.0] day of the disease, under the condition of nitrotyrosine level >481.97 nmol/ml (AUC = 0.909, p < 0.001), the probability of developing oxygen dependence is significant. And under the conditions of nitrotyrosine level >521.96 nmol/ml during this observation period, the probability of a fatal outcome of the disease is significant (AUC = 0.842, p < 0.001). The established correlations confirm the clinical-pathogenetic role of nitrotyrosative stress in the development of the “cytokine storm” and multiorgan failure. The content of nitrotyrosine correlates with the level of C-reactive protein (r = +0.25, p < 0.05), the ratio of absolute neutrophil count to absolute lymphocyte count (r = +0.26, p < 0.05), alanine aminotransferase activity (r = +0.26, p < 0.05) and glomerular filtration rate (r = -0.27, p < 0.05). The diagnostic value of determining the level of nitrotyrosine in predicting the course of COVID-19 with pneumonia against the background of treatment after 7 days lies in the possibility of predicting the probability of a fatal outcome of the disease. Namely, the preservation of the level of nitrotyrosine >507.98 nmol/ml (AUC = 0.681, p < 0.001) during the specified period of observation indicates a high probability of a fatal outcome of the disease. Conclusions. In patients with COVID-19 with pneumonia, the level of nitrotyrosine elevation in the blood serum depends on the appearance of oxygen dependence and the outcome of the disease. The highest level of nitrotyrosine is in patients with COVID-19 with pneumonia with a severe course, and the degree of increase of this indicator has diagnostic value in predicting the probability of an unfavorable disease course.

Background: Paracoccidioidomycosis (PCM) is a systemic endemic fungal disease prevalent in Latin America. Previous studies revealed that host immunity against PCM is tightly regulated by several suppressive mechanisms mediated by tolerogenic plasmacytoid dendritic cells, the enzyme 2,3 indoleamine dioxygenase (IDO-1), regulatory T-cells (Tregs), and through the recruitment and activation of myeloid-derived suppressor cells (MDSCs). We have recently shown that Dectin-1, TLR2, and TLR4 signaling influence the IDO-1-mediated suppression caused by MDSCs. However, the contribution of these receptors in the production of important immunosuppressive molecules used by MDSCs has not yet been explored in pulmonary PCM. Methods: We evaluated the expression of PD-L1, IL-10, as well as nitrotyrosine by MDSCs after anti-Dectin-1, anti-TLR2, and anti-TLR4 antibody treatment followed by P. brasiliensis yeasts challenge in vitro. We also investigated the influence of PD-L1, IL-10, and nitrotyrosine in the suppressive activity of lung-infiltrating MDSCs of C57BL/6-WT, Dectin-1KO, TLR2KO, and TLR4KO mice after in vivo fungal infection. The suppressive activity of MDSCs was evaluated in cocultures of isolated MDSCs with activated T-cells. Results: A reduced expression of IL-10 and nitrotyrosine was observed after in vitro anti-Dectin-1 treatment of MDSCs challenged with fungal cells. This finding was further confirmed in vitro and in vivo by using Dectin-1KO mice. Furthermore, MDSCs derived from Dectin-1KO mice showed a significantly reduced immunosuppressive activity on the proliferation of CD4+ and CD8+ T lymphocytes. Blocking of TLR2 and TLR4 by mAbs and using MDSCs from TLR2KO and TLR4KO mice also reduced the production of suppressive molecules induced by fungal challenge. In vitro, MDSCs from TLR4KO mice presented a reduced suppressive capacity over the proliferation of CD4+ T-cells. Conclusion: We showed that the pathogen recognition receptors (PRRs) Dectin-1, TLR2, and TLR4 contribute to the suppressive activity of MDSCs by inducing the expression of several immunosuppressive molecules such as PD-L1, IL-10, and nitrotyrosine. This is the first demonstration of a complex network of PRRs signaling in the induction of several suppressive molecules by MDSCs and its contribution to the immunosuppressive mechanisms that control immunity and severity of pulmonary PCM. [ABSTRACT FROM AUTHOR]

Aim: Multiple processes have been demonstrated to elucidate the biological toxicity of mercuric chloride, among which oxidative stress has been identified as a contributing factor. The superoxide radical has the potential to induce peroxidation of lipid membranes, alter the activities of proteins and antioxidant enzymes, and modulate gene transcription. Additionally, it has the ability to swiftly deactivate nitric Oxide, resulting in impairment of endothelial function and causing harm to macromolecules, membranes, and DNA by generating more harmful radicals including peroxynitrite and hydroxyl radicals. The formation of nitrotyrosine occurs through the interaction between peroxynitrite and tyrosine residues found in proteins. Nitrotyrosine serves as a useful marker for assessing the possible cytotoxic impacts of nitric oxide. While there have been previous animal tests undertaken, the existing literature we have reviewed does not provide evidence regarding the impact of direct mercury exposure and mercury toxicity on nitrotyrosine and nitric oxide. In order to achieve our research objectives, we have devised a plan to investigate the presence of nitrotyrosine and nitric oxide in the blood serum of children who have been exposed to mercury in our study. Materials and Methods: Our study included 65 patients, 42 girls and 23 boys, who had accidentally come into contact with mercury in the laboratories of some schools in Kahramanmaraş, and whose blood mercury level was over 10 µg/l and/or whose urine mercury level was over 15 µg/l. The control group of the study included a total of 23 children, 17 girls and 6 boys, who applied to the pediatric clinic with various complaints, without intoxication or neurological findings, and from whom blood samples would be taken for different diagnoses. Results: Nitric oxide and nitrotyrosine levels were found to be higher in children exposed to mercury than in the control group (p<0.01). Nitric oxide, nitrotyrosine and mercury levels in the patients were high in both genders, and no gender-related difference was detected (p>0.05). The mean duration of mercury exposure was 45 minutes. Of the 65 patients, 20 were asymptomatic and 40 were symptomatic. The most common symptoms were headache and nausea. Conclusion: The existing body of research predominantly focuses on investigating the association between mercury poisoning and oxidative stress biomarkers through animal studies, with a limited number of studies conducted on human subjects. Our study has made a valuable contribution to the existing literature by successfully detecting elevated levels of nitric oxide and nitrotyrosine in children who have been diagnosed with mercury poisoning. [ABSTRACT FROM AUTHOR]

Influenza viruses are deadly respiratory pathogens of special importance due to their long history of global pandemics. During influenza virus infections, the host responds by producing interferons, which activate interferon-stimulated genes (ISGs) inside target cells. One of these ISGs is inducible nitric oxide synthase (iNOS). iNOS produces nitric oxide (NO) from arginine and molecular oxygen inside the cell. NO can react with superoxide radicals to form reactive nitrogen species, principally peroxynitrite. While much work has been done studying the many roles of nitric oxide in influenza virus infections, the direct effect of peroxynitrite on influenza virus proteins has not been determined. Manipulations of NO, either by knocking out iNOS or chemically inhibiting NO, produced no change in virus titers in mouse models of influenza infection. However, peroxynitrite has a known antimicrobial effect on various bacteria and parasites, and the reason for its lack of antimicrobial effect on influenza virus titers in vivo remains unclear. Therefore, we wished to test the direct effect of nitration of influenza virus proteins. We examined the impact of nitration on virus infectivity, replication, and immunogenicity. We observed that the nitration of influenza A virus proteins decreased virus infectivity and replication ex vivo. We also determined that the nitration of influenza virus hemagglutinin protein can reduce antibody responses to native virus protein. However, our study also suggests that nitration of influenza virus proteins in vivo is likely not extensive enough to inhibit virus functions substantially. These findings will help clarify the role of peroxynitrite during influenza virus infections. IMPORTANCE Nitric oxide and peroxynitrite produced during microbial infections have diverse and seemingly paradoxical functions. While nitration of lung tissue during influenza virus infection has been observed in both mice and humans, the direct effect of protein nitration on influenza viruses has remained elusive. We addressed the impact of nitration of influenza virus proteins on virus infectivity, replication, and immunogenicity. We observed that ex vivo nitration of influenza virus proteins reduced virus infectivity and immunogenicity. However, we did not detect nitration of influenza virus hemagglutinin protein in vivo. These results contribute to our understanding of the roles of nitric oxide and peroxynitrite in influenza virus infections.

The aim of the research is to determine the clinical-pathogenetic and prognostic value of nitrotyrosine levels in the blood serum of patients with COVID-19 with pneumonia in the development of oxygen dependence and the risk of fatal outcome. Materials and methods. 123 patients with COVID-19 with pneumonia were examined, who were examined and treated according to the Order of the Ministry of Health of Ukraine dated March 28, 2020 No. 722. Patients were divided into groups: I group – 32 patients with a moderate course without oxygen dependence; II group – 91 patients with a severe course with the presence of oxygen dependence. Patients in the II group were additionally divided into subgroups: II-A subgroup – 45 patients who recovered; II-B subgroup – 46 patients who died. The content of nitrotyrosine (Hycult Biotech, the Netherlands) was determined in the blood serum by the immunoenzymatic method. Statistical data processing was carried out in the program Statistica for Windows 13 (StatSoft Inc., No. JPZ804I382130ARCN10-J). Results. The content of nitrotyrosine in the blood serum of patients with COVID-19 with pneumonia in a severe course with the development of oxygen dependence is higher (p < 0.001) than in patients with a moderate course of the disease without signs of oxygen dependence. The level of its increase has an inverse correlation with the oxygen saturation index (r = -0.53, р < 0.05). When hospitalized for 9.0 [7.0; 12.0] day of the disease, under the condition of nitrotyrosine level >481.97 nmol/ml (AUC = 0.909, p < 0.001), the probability of developing oxygen dependence is significant. And under the conditions of nitrotyrosine level >521.96 nmol/ml during this observation period, the probability of a fatal outcome of the disease is significant (AUC = 0.842, p < 0.001). The established correlations confirm the clinical-pathogenetic role of nitrotyrosative stress in the development of the “cytokine storm” and multiorgan failure. The content of nitrotyrosine correlates with the level of C-reactive protein (r = +0.25, p < 0.05), the ratio of absolute neutrophil count to absolute lymphocyte count (r = +0.26, p < 0.05), alanine aminotransferase activity (r = +0.26, p < 0.05) and glomerular filtration rate (r = -0.27, p < 0.05). The diagnostic value of determining the level of nitrotyrosine in predicting the course of COVID-19 with pneumonia against the background of treatment after 7 days lies in the possibility of predicting the probability of a fatal outcome of the disease. Namely, the preservation of the level of nitrotyrosine >507.98 nmol/ml (AUC = 0.681, p < 0.001) during the specified period of observation indicates a high probability of a fatal outcome of the disease. Conclusions. In patients with COVID-19 with pneumonia, the level of nitrotyrosine elevation in the blood serum depends on the appearance of oxygen dependence and the outcome of the disease. The highest level of nitrotyrosine is in patients with COVID-19 with pneumonia with a severe course, and the degree of increase of this indicator has diagnostic value in predicting the probability of an unfavorable disease course. [ABSTRACT FROM AUTHOR]

Objective • To observe the levels of serum 3-nitrotyrosine (3-NT), neuronal PAS domain protein 4 (NPASDP-4), and S100β protein in patients diagnosed with cerebral infarction and analyze their correlation with cognitive dysfunction in these patients. Methods • The study included a cohort of 158 patients suffering from cerebral infarction who were admitted to the Liwan District Hospital of Traditional Chinese Medicine between January 2021 and December 2022. After stabilizing vital signs, all patients underwent the Montreal Cognitive Assessment (MoCA) to assess their cognitive function. Based on the assessment results, they were divided into two groups: the cognitive dysfunction group (121 cases) and the normal cognitive function group (37 cases). The baseline characteristics and serum levels of 3-NT, neuronal PAS domain protein 4 (NPASDP-4), and S100β protein were compared in the patient cohorts. Furthermore, the correlation between these three indicators and cognitive function in patients suffering from cerebral infarction was analyzed. A logistic regression model was constructed to analyze how serum levels of 3-NT, NPASDP-4, and S100β protein levels affected cognitive function in patients suffering from cerebral infarction. ROC curve analysis was conducted to assess the predictive value of serum 3-NT, NPASDP-4, and S100β protein levels for cognitive function in patients suffering from cerebral infarction. Results • Among the 158 patients with cerebral infarction, 121 (76.58%) had cognitive dysfunction, while 37 (23.42%) had normal cognitive function. The levels of 3-NT, NPASDP-4, and S100β protein were found to be significantly higher in the cognitive dysfunction group compared to the normal cognitive function group (t = 5.788, 7.774, 6.460; P = .000, .000, .000). The point-biserial correlation analysis results showed a positive correlation between serum levels of 3-NT, NPASDP-4, and S100β protein and the occurrence of cognitive dysfunction in patients suffering from cerebral infarction (r=0.420, 0.529, 0.424; P = .000, .000, .000). The logistic regression model demonstrated that serum levels of 3-NT(95%CI: 1.299-2.603), NPASDP-4(95%CI: 1.487-3.386), and S100β protein(95%CI: 1.153-8.746) were risk factors for cognitive dysfunction in patients suffering from cerebral infarction (OR=1.839, 2.244, 1.429; P = .001, .000, .240). ROC curve analysis demonstrated that serum 3-NT, NPASDP-4, and S100β protein levels exhibited a certain predictive value for cognitive function in patients with cerebral infarction (AUC = 0.789, 0.881, 0.820). Conclusion • Serum levels of 3-NT, NPASDP-4, and S100β protein are closely related to the cognitive function of patients with cerebral infarction, and abnormal changes in these levels may exacerbate cognitive dysfunction in these patients. [ABSTRACT FROM AUTHOR]

Dental caries can lead to inflammation or necrosis of the pulp, necessitating root canal treatment. However, this treatment carries the risk of pain, with its incidence influenced by the condition and quality of the pulp tissue. Immunologic and microbiologic factors play significant roles in determining the quality of the pulp tissue, thereby impacting the diagnosis of pulp tissue health. To elucidate the reduction in cell count resulting from the intrinsic apoptosis pathway of dental pulp nerve cells subsequent to lipopolysaccharide (LPS) administration, based on the expression levels of nitrotyrosine and F2-isoprostane. Thirty-two Sprague Dawley rats were divided into two groups. In the control group, only access opening was performed on the mandibular incisors of the rats. Conversely, in the treatment group, access opening was performed, and lipopolysaccharide (LPS) from Porphyromonas gingivalis was induced, left for 48 hours to induce an inflammatory condition, and subsequently terminated. Immunohistochemical staining was then employed to assess the expression of nitrotyrosine and F2-isoprostane. Additionally, the number of dental pulp nerve cells was observed using hematoxylin and eosin (HE) staining. Significant differences were observed in the expression levels of nitrotyrosine and F2- isoprostane, as well as in the number of nerve cells, between the control and treatment groups. Administration of lipopolysaccharide (LPS) leads to increased expression of nitrotyrosine and F2- isoprostane, while concurrently decreasing the number of dental pulp nerve cells affected by inflammation. [ABSTRACT FROM AUTHOR]

Ischemic cerebrovascular accident (iCVA) is a public health issue, whose subjacent events involve the development of nitroxidative distress. Identifying biomarkers that assist in the diagnosis of this disease has clinically relevant implications. The aim of this study was to develop an analytic tool for measuring nitroxidative distress biomarkers, intended for application in clinical practice to enhance patient healthcare. Three enzyme linked immunosorbent assays (ELISA) were developed, with different detection objectives. One of them, in a sandwich format, quantifies the amount of fibrinogen in human plasma, an important glycoprotein involved in the blood coagulation process, contributing to thrombus formation and thereby participating in the mechanism of ischemic stroke. Another ELISA, also in a sandwich format, detects the presence of nitrotyrosine residues in fibrinogen from human plasma, a nitroxidative posttranslational modification resulting from the attack of peroxynitrite by-products on tyrosine residues present in proteins. The third one, in inhibition format, determines human plasma nitrotyrosine total content and was used to analyze human plasma samples from control and iCVA patients. Those two groups of plasma samples were analyzed using inhibition ELISA, revealing statistically significant differences in their nitrotyrosine content and molar ratios of nitrotyrosine to fibrinogen, which were higher in the iCVA group. This study provides evidence that nitroxidative distress occurs in ischemic stroke, as indicated by the detection of the biomarker nitrotyrosine. This finding supports other studies that also identified nitrotyrosine in ischemic stroke, through several different methods. This specific ELISA method is applicable for the rapid analysis of clinical samples, making it a potential clinical tool for assessing iCVA patients. [ABSTRACT FROM AUTHOR]

Tubulin tyrosine ligase 12 (TTLL12) is a promising target for therapeutic intervention since it has been implicated in tumour progression, the innate immune response to viral infection, ciliogenesis and abnormal cell division. It is the most mysterious of a fourteen-member TTL/TTLL family, since, although it is the topmost conserved in evolution, it does not have predicted enzymatic activities. TTLL12 seems to act as a pseudo-enzyme that modulates various processes indirectly. Given the need to target its functions, we initially set out to identify a property of TTLL12 that could be used to develop a reliable high-throughput screening assay. We discovered that TTLL12 suppresses the cell toxicity of nitrotyrosine (3-nitrotyrosine) and its ligation to the C-terminus of detyrosinated α-tubulin (abbreviated to ligated-nitrotyrosine). Nitrotyrosine is produced by oxidative stress and is associated with cancer progression. Ligation of nitrotyrosine has been postulated to be a check-point induced by excessive cell stress. We found that the cytotoxicities of nitrotyrosine and tubulin poisons are independent of one another, suggesting that drugs that increase nitrotyrosination could be complementary to current tubulin-directed therapeutics. TTLL12 suppression of nitrotyrosination of α-tubulin was used to develop a robust cell-based ELISA assay that detects increased nitrotyrosination in cells that overexpress TTLL12 We adapted it to a high throughput format and used it to screen a 10,000 molecule World Biological Diversity SETTM collection of low-molecular weight molecules. Two molecules were identified that robustly activate nitrotyrosine ligation at 1 μM concentration. This is the pioneer screen for molecules that modulate nitrotyrosination of α-tubulin. The molecules from the screen will be useful for the study of TTLL12, as well as leads for the development of drugs to treat cancer and other pathologies that involve nitrotyrosination. [ABSTRACT FROM AUTHOR]

Hypoxia can induce pulmonary edema (PE) and inflammation. Furthermore, hypoxia depresses left ventricular (LV) inotropy despite sympathetic activation. To study the role of hypoxic sympathetic activation, we investigated the effects of hypoxia with and without adrenergic blockade (AB) on cardiovascular dysfunction and lung injury, i.e., pulmonary edema, congestion, inflammation, and nitrosative stress. Eighty-six female rats were exposed for 72 h to normoxia or normobaric hypoxia and received infusions with NaCl, prazosin, propranolol, or prazosin–propranolol combination. We evaluated hemodynamic function and performed histological and immunohistochemical analyses of the lung. Hypoxia significantly depressed LV but not right ventricular (RV) inotropic and lusitropic functions. AB significantly decreased LV function in both normoxia and hypoxia. AB effects on RV were weaker. Hypoxic rats showed signs of moderate PE and inflammation. This was accompanied by elevated levels of tumor necrosis factor α (TNFα) and nitrotyrosine, a marker of nitrosative stress in the lungs. In hypoxia, all types of AB markedly reduced both TNFα and nitrotyrosine. However, AB did not attenuate PE. The results suggest that hypoxia-induced sympathetic activation contributes to inflammation and nitrosative stress in the lungs but not to PE. We suggest that AB in hypoxia aggravates hypoxia-induced inotropic LV dysfunction and backlog into the pulmonary circulation, thus promoting PE.

The impact of coronavirus on the reproductive health of men attracts the special attention of many researchers. While studies suggest changes in sperm parameters and the possibility of testicular inflammation, further studies are needed to elucidate any potential age-related changes in these findings, which is the purpose of the present study. The semen quality parameters, cytokine concentration, and markers of the pro- and antioxidant system were assessed in 60 men five to seven months after the coronavirus infection and in 77 controls (without a history of coronavirus infection). Additionally, participants were divided into two age groups: less than 35 years and 35 years or older. Notably increased round cell count in ejaculate and reduced sperm hyaluronan binding ability were observed among post-infection patients younger than 35 years. In the same group, a decline in seminal plasma zinc levels and nitrotyrosine in the cell fraction was found. In men over 35 years of age, Coronavirus Disease 2019 (COVID-19) led to increased sperm DNA fragmentation, a decrease in the total antioxidant capacity, and an elevation in the levels of interleukin-1β and interleukin-10. The concentration of interleukin-1β decreased over time following recovery in all affected patients. The data obtained suggest the potential adverse impact of the coronavirus infection on male reproductive health; however, these effects appear to be age-dependent. [ABSTRACT FROM AUTHOR]

Introduction: We have acquired significant knowledge regarding the pathogenesis of severe acute respiratory syndrome caused by coronavirus 2 (SARS-CoV-2). However, the underlying mechanisms responsible for disease recovery still need to be fully understood. Methods: To gain insights into critical immune markers involved in COVID-19 etiopathogenesis, we studied the evolution of the immune profile of peripheral blood samples from patients who had recovered from COVID-19 and compared them to subjects with severe acute respiratory illness but negative for SARSCoV-2 detection (controls). In addition, linear and clustered correlations between different parameters were determined. Results: The data obtained revealed a significant reduction in the frequency of inflammatory monocytes (CD14+CD16+) at hospital discharge vs. admission. Remarkably, nitric oxide (NO) production by the monocyte compartment was significantly reduced at discharge. Furthermore, interleukin (IL)-6 plasma levels were negatively correlated with the frequency of NO+CD14+CD16+ monocytes at hospital admission. However, at the time of hospital release, circulating IL-6 directly correlated with the NO production rate by monocytes. In line with these observations, we found that concomitant with NO diminution, the level of nitrotyrosine (NT) on CD8 T-cells significantly diminished at the time of hospital release. Considering that purinergic signaling constitutes another regulatory system, we analyzed the kinetics of CD39 and CD73 ectoenzyme expression in CD8 T-cells. We found that the frequency of CD39+CD8+ T-cells significantly diminished while the percentage of CD73+ cells increased at hospital discharge. In vitro, IL-6 stimulation of PBMCs from COVID-19 patients diminished the NT levels on CD8 T-cells. A clear differential expression pattern of CD39 and CD73 was observed in the NT+ vs. NT-CD8+ T-cell populations. Discussion: The results suggest that early after infection, IL-6 controls the production of NO, which regulates the levels of NT on CD8 T-cells modifying their effector functions. Intriguingly, in this cytotoxic cell population, the expression of purinergic ectoenzymes is tightly associated with the presence of nitrated surface molecules. Overall, the data obtained contribute to a better understanding of pathogenic mechanisms associated with COVID-19 outcomes. [ABSTRACT FROM AUTHOR]

Intrauterine hypoxia in newborns leads to a multifaceted array of alterations that exert a detrimental impact on the cardiovascular system. The aim of this research was to assess the cardioprotective effects of modulators of the nitric oxide (NO) system, including L-arginine, Thiotriazoline, Angiolin, and Mildronate, during the early postnatal period following intrauterine hypoxia. Methods: The study involved 50 female white rats. Pregnant female rats were given a daily intraperitoneal dose of 50 mg/kg of sodium nitrite starting on the 16th day of pregnancy. A control group of pregnant rats received saline instead. The resulting offspring were divided into the following groups: Group 1—intact rats; Group 2—rat pups subjected to prenatal hypoxia (PH) and daily treated with physiological saline; and Groups 3 to 6—rat pups exposed to prenatal hypoxia and treated daily from the 1st to the 30th day after birth. Nitrotyrosine levels, eNOS, iNOS, and NO metabolites were evaluated using ELISA; to measure the expression levels of iNOS mRNA and eNOS mRNA, a PCR test was utilized. Results: Angiolin enhances the expression of eNOS mRNA and boosts eNOS activity in the myocardium of rats with ischemic conditions. Arginine and particularly Thiotriazoline exhibited a consistent impact in restoring normal parameters of the cardiac nitroxidergic system following PH. Mildronate notably raised iNOS mRNA levels and notably reduced nitrotyrosine levels, providing further support for its antioxidative characteristics. [ABSTRACT FROM AUTHOR]

In rats, acute normobaric hypoxia depressed left ventricular (LV) inotropic function. After 24 h of hypoxic exposure, a slight recovery of LV function occurred. We speculated that prolonged hypoxia (72 h) would induce acclimatization and, hence, recovery of LV function. Moreover, we investigated biomarkers of nitrosative stress and apoptosis as possible causes of hypoxic LV depression. To elucidate the role of hypoxic sympathetic activation, we studied whether adrenergic blockade would further deteriorate the general state of the animals and their cardiac function. Ninety-four rats were exposed over 72 h either to normal room air (N) or to normobaric hypoxia (H). The rodents received infusion (0.1 mL/h) with 0.9% NaCl or with different adrenergic blockers. Despite clear signs of acclimatization to hypoxia, the LV depression continued persistently after 72 h of hypoxia. Immunohistochemical analyses revealed significant increases in markers of nitrosative stress, adenosine triphosphate deficiency and apoptosis in the myocardium, which could provide a possible explanation for the absence of LV function recovery. Adrenergic blockade had a slightly deteriorative effect on the hypoxic LV function compared to the hypoxic group with maintained sympathetic efficacy. These findings show that hypoxic sympathetic activation compensates, at least partially, for the compromised function in hypoxic conditions, therefore emphasizing its importance for hypoxia adaptation. [ABSTRACT FROM AUTHOR]

The nitration of tyrosyl residues in proteins is considered a type of post-translational modification of proteins, indicating disruptions in the metabolic and signaling functions of nitric oxide •NO and the development of oxidative nitrosative stress. We have examined the nonenzymatic pathway of protein nitration by the action of visible light in the presence of riboflavin and nitrite. Mass spectrometry was used to show that riboflavin-photosensitized redox processes involving nitrite and tyrosine or tyrosyl residues lead to nitration of residues Tyr-103 and Tyr-146 in the polypeptide chain of horse heart myoglobin. A possible role is discussed for riboflavin and other natural photosensitizers in the modification and damage of proteins when the body is exposed to intense visible light in the presence of nitrites in the blood. [ABSTRACT FROM AUTHOR]

The vegetal polyphenol curcumin displays beneficial effects against skeletal muscle derangement induced by oxidative stress, disuse or aging. Since oxidative stress and inflammation are involved in the progression of muscle dystrophy, the effects of curcumin administration were investigated in the diaphragm of mdx mice injected intraperitoneally or subcutaneously with curcumin for 4–12–24 weeks. Curcumin treatment independently of the way and duration of administration (i) ameliorated myofiber maturation index without affecting myofiber necrosis, inflammation and degree of fibrosis; (ii) counteracted the decrease in type 2X and 2B fiber percentage; (iii) increased about 30% both twitch and tetanic tensions of diaphragm strips; (iv) reduced myosin nitrotyrosination and tropomyosin oxidation; (v) acted on two opposite nNOS regulators by decreasing active AMP-Kinase and increasing SERCA1 protein levels, the latter effect being detectable also in myotube cultures from mdx satellite cells. Interestingly, increased contractility, decreased myosin nitrotyrosination and SERCA1 upregulation were also detectable in the mdx diaphragm after a 4-week administration of the NOS inhibitor 7-Nitroindazole, and were not improved further by a combined treatment. In conclusion, curcumin has beneficial effects on the dystrophic muscle, mechanistically acting for the containment of a deregulated nNOS activity. [ABSTRACT FROM AUTHOR]

Oxidative stress is proposed in the literature as an important player in the development of CHF and correlates with left ventricle (LV) dysfunction and hypertrophy in the failing heart. In this study, we aimed to verify if the serum oxidative stress markers differ in chronic heart failure (CHF) patients' groups depending on the LV geometry and function. Patients were stratified into two groups according to left ventricular ejection fraction (LVEF) values: HFrEF (<40% (n = 27)) and HFpEF (≥40% (n = 33)). Additionally, patients were stratified into four groups according to LV geometry: NG–normal left ventricle geometry (n = 7), CR–concentric remodeling (n = 14), cLVH–concentric LV hypertrophy (n = 16), and eLVF–eccentric LV hypertrophy (n = 23). We measured protein (protein carbonyl (PC), nitrotyrosine (NT-Tyr), dityrosine), lipid (malondialdehyde (MDA), oxidizes (HDL) oxidation and antioxidant (catalase activity, total plasma antioxidant capacity (TAC) markers in serum. Transthoracic echocardiogram analysis and lipidogram were also performed. We found that oxidative (NT-Tyr, dityrosine, PC, MDA, oxHDL) and antioxidative (TAC, catalase) stress marker levels did not differ between the groups according to LVEF or LV geometry. NT-Tyr correlated with PC (rs = 0.482, p = 0.000098), and oxHDL (rs = 0.278, p = 0.0314). MDA correlated with total (rs = 0.337, p = 0.008), LDL (rs = 0.295, p = 0.022) and non-HDL (rs = 0.301, p = 0.019) cholesterol. NT-Tyr negatively correlated with HDL cholesterol (rs = -0.285, p = 0.027). LV parameters did not correlate with oxidative/antioxidative stress markers. Significant negative correlations were found between the end-diastolic volume of the LV and the end-systolic volume of the LV and HDL-cholesterol (rs = –0.935, p < 0.0001; rs = –0.906, p < 0.0001, respectively). Significant positive correlations between both the thickness of the interventricular septum and the thickness of the LV wall and the levels of triacylglycerol in serum (rs = 0.346, p = 0.007; rs = 0.329, p = 0.010, respectively) were found. In conclusions, we did not find a difference in serum concentrations of both oxidant (NT-Tyr, PC, MDA) and antioxidant (TAC and catalase) concentrations in CHF patients' groups according to LV function and geometry was found. The geometry of the LV could be related to lipid metabolism in CHF patients, and no correlation between oxidative/antioxidant and LV markers in CHF patients was found. [ABSTRACT FROM AUTHOR]

Kaposi's Sarcoma (KS) is a heterogenous, multifocal vascular malignancy caused by the human herpesvirus 8 (HHV8), also known as Kaposi's Sarcoma-Associated Herpesvirus (KSHV). Here, we show that KS lesions express iNOS/NOS2 broadly throughout KS lesions, with enrichment in LANA positive spindle cells. The iNOS byproduct 3-nitrotyrosine is also enriched in LANA positive tumor cells and colocalizes with a fraction of LANA-nuclear bodies. We show that iNOS is highly expressed in the L1T3/mSLK tumor model of KS. iNOS expression correlated with KSHV lytic cycle gene expression, which was elevated in late-stage tumors (>4 weeks) but to a lesser degree in early stage (1 week) xenografts. Further, we show that L1T3/mSLK tumor growth is sensitive to an inhibitor of nitric oxide, L-NMMA. L-NMMA treatment reduced KSHV gene expression and perturbed cellular gene pathways relating to oxidative phosphorylation and mitochondrial dysfunction. These finding suggest that iNOS is expressed in KSHV infected endothelial-transformed tumor cells in KS, that iNOS expression depends on tumor microenvironment stress conditions, and that iNOS enzymatic activity contributes to KS tumor growth.

Pesticides are widely used to control weeds and pests in agricultural settings but harm non-target aquatic organisms. In this study, our objective was to evaluate the effect of short-term exposure (one week) to environmentally relevant concentrations of pesticides mixture (low concentration: 0.4 μg/l atrazine, 0.5 μg/l Roundup®, and 0.5 μg/l 2,4-D; high concentration: 0.8 μg/l atrazine, 1 μg/l Roundup®, and 1 μg/l 2,4-D) on tissue architecture, body fluid conditions, and 3-nitrotyrosine protein (NTP) and Na+/K+-ATPase, expressions in tissues of American oyster (Crassostrea virginica) under controlled laboratory conditions. Histological analysis demonstrated the atrophy in the gills and digestive glands of oysters exposed to pesticides mixture. Periodic acid-Schiff (PAS) staining showed the number of hemocytes in connective tissue increased in low- and high-concentration pesticides exposure groups. However, pesticides treatment significantly (P < 0.05) decreased the amount of mucous secretion in the gills and digestive glands of oysters. The extrapallial fluid (i.e., body fluid) protein concentrations and glucose levels were dropped significantly (P < 0.05) in oysters exposed to high-concentration pesticides exposure groups. Moreover, immunohistochemical analysis showed significant upregulations of NTP and Na+/K+-ATPase expressions in the gills and digestive glands in pesticides exposure groups. Our results suggest that exposure to environmentally relevant pesticides mixture causes morphological changes in tissues and alters body fluid conditions and NTP and Na+/K+-ATPase expressions in tissues, which may lead to impaired physiological functions in oysters. [Display omitted] • Pesticides are widely used to control weeds and pests in agricultural settings. • Aquatic environments are becoming increasingly inundated by pesticides. • Pesticides harm non-target aquatic organisms. • Pesticides altered the morphology of gills and digestive glands of oysters. • Pesticides induced nitrative stress and Na+/K+-ATPase expression in oysters. [ABSTRACT FROM AUTHOR]

The increased production of reactive oxygen species (ROS) has been postulated to play a key role in the progression of nonalcoholic fatty liver disease (NAFLD). However, the source of ROS and mechanisms underlying the development of NAFLD have yet to be established. We observed a significant up-regulation of a minor isoform of NADPH oxidase, NOX1, in the liver of nonalcoholic steatohepatitis (NASH) patients as well as of mice fed a high-fat and high-cholesterol (HFC) diet for 8 weeks. In mice deficient in Nox1 (Nox1KO), increased levels of serum alanine aminotransferase and hepatic cleaved caspase-3 demonstrated in HFC diet-fed wild-type mice (WT) were significantly attenuated. Concomitantly, increased protein nitrotyrosine adducts, a marker of peroxynitrite-induced injury detected in hepatic sinusoids of WT, were significantly suppressed in Nox1KO. The expression of NOX1 mRNA was much higher in the fractions of enriched liver sinusoidal endothelial cells (LSECs) than in those of hepatocytes. In primary cultured LSECs, palmitic acid (PA) up-regulated the mRNA level of NOX1, but not of NOX2 or NOX4. The production of nitric oxide by LSECs was significantly attenuated by PA-treatment in WT but not in Nox1KO. When the in vitro relaxation of TWNT1, a cell line that originated from hepatic stellate cells, was assessed by the gel contraction assay, the relaxation of stellate cells induced by LSECs was attenuated by PA treatment. In contrast, the relaxation effect of LSECs was preserved in cells isolated from Nox1KO. Taken together, the up-regulation of NOX1 in LSECs may elicit peroxynitrite-mediated cellular injury and impaired hepatic microcirculation through the reduced bioavailability of nitric oxide. ROS derived from NOX1 may therefore constitute a critical component in the progression of NAFLD.

The blood labyrinthine barrier (BLB) is critical in the maintenance of inner ear ionic and fluid homeostasis. Recent studies using imaging and histopathology demonstrate loss of integrity of the BLB in the affected inner ear of Menieres disease (MD) patients. We hypothesized that oxidative stress is involved in the pathogenesis of BLB degeneration, and to date there are no studies of oxidative stress proteins in the human BLB. We investigated the ultrastructural and immunohistochemical changes of the BLB in the vestibular endorgan, the macula utricle, from patients with MD (n = 10), acoustic neuroma (AN) (n = 6) and normative autopsy specimens (n = 3) with no inner ear disease. Each subject had a well-documented clinical history and audiovestibular testing. Utricular maculae were studied using light and transmission electron microscopy and double labeling immunofluorescence. Vascular endothelial cells (VECs) were identified using isolectin B4 (IB4) and glucose-transporter-1 (GLUT-1). Pericytes were identified using alpha smooth muscle actin (αSMA) and phalloidin. IB4 staining of VECS was consistently seen in both AN and normative. In contrast, IB4 was nearly undetectable in all MD specimens, consistent with the significant VEC damage confirmed on transmission electron microscopy. GLUT-1 was present in MD, AN, and normative. αSMA and phalloidin were expressed consistently in the BLB pericytes in normative, AN specimen, and Menieres specimens. Endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), and nitrotyrosine were used as markers of oxidative stress. The VECs of the BLB in Menieres had significantly higher levels of expression of iNOS and nitrotyrosine compared with normative and AN specimen. eNOS-IF staining showed similar patterns in normative and Menieres specimens. Microarray-based gene expression profiling confirmed upregulation of iNOS mRNA from the macula utricle of Menieres patients compared with AN. Nitrotyrosine, a marker recognized as a hallmark of inflammation, especially when seen in association with an upregulation of iNOS, was detected in the epithelial and stromal cells in addition to VECs in MD. Immunohistochemical and ultrastructural degenerative changes of the VEC suggest that these cells are the primary targets of oxidative stress, and pericyte pathology including degeneration and migration, likely also plays a role in the loss of integrity of the BLB and triggering of inflammatory pathways in MD. These studies advance our scientific understanding of oxidative stress in the human inner ear BLB and otopathology.

ABSTRACT Influenza viruses are deadly respiratory pathogens of special importance due to their long history of global pandemics. During influenza virus infections, the host responds by producing interferons, which activate interferon-stimulated genes (ISGs) inside target cells. One of these ISGs is inducible nitric oxide synthase (iNOS). iNOS produces nitric oxide (NO) from arginine and molecular oxygen inside the cell. NO can react with superoxide radicals to form reactive nitrogen species, principally peroxynitrite. While much work has been done studying the many roles of nitric oxide in influenza virus infections, the direct effect of peroxynitrite on influenza virus proteins has not been determined. Manipulations of NO, either by knocking out iNOS or chemically inhibiting NO, produced no change in virus titers in mouse models of influenza infection. However, peroxynitrite has a known antimicrobial effect on various bacteria and parasites, and the reason for its lack of antimicrobial effect on influenza virus titers in vivo remains unclear. Therefore, we wished to test the direct effect of nitration of influenza virus proteins. We examined the impact of nitration on virus infectivity, replication, and immunogenicity. We observed that the nitration of influenza A virus proteins decreased virus infectivity and replication ex vivo. We also determined that the nitration of influenza virus hemagglutinin protein can reduce antibody responses to native virus protein. However, our study also suggests that nitration of influenza virus proteins in vivo is likely not extensive enough to inhibit virus functions substantially. These findings will help clarify the role of peroxynitrite during influenza virus infections. IMPORTANCE Nitric oxide and peroxynitrite produced during microbial infections have diverse and seemingly paradoxical functions. While nitration of lung tissue during influenza virus infection has been observed in both mice and humans, the direct effect of protein nitration on influenza viruses has remained elusive. We addressed the impact of nitration of influenza virus proteins on virus infectivity, replication, and immunogenicity. We observed that ex vivo nitration of influenza virus proteins reduced virus infectivity and immunogenicity. However, we did not detect nitration of influenza virus hemagglutinin protein in vivo. These results contribute to our understanding of the roles of nitric oxide and peroxynitrite in influenza virus infections.

Nitric oxide (NO) is a critical molecule that links plant development with stress responses. Herein, new insights into the role of NO metabolism during leaf senescence in Arabidopsis are presented. A gradual decrease in NO emission accompanied dark-induced leaf senescence (DILS), and a transient wave of peroxynitrite (ONOO–) formation was detected by day 3 of DILS. The boosted ONOO– did not promote tryptophan (Trp) nitration, while the pool of 6-nitroTrp-containing proteins was depleted as senescence progressed. Immunoprecipitation combined with mass spectrometry was used to identify 63 and 4 characteristic 6-nitroTrp-containing proteins in control and individually darkened leaves, respectively. The potential in vivo targets of Trp nitration were mainly related to protein biosynthesis and carbohydrate metabolism. In contrast, nitration of tyrosine-containing proteins was intensified 2-fold on day 3 of DILS. Also, nitrative modification of RNA and DNA increased significantly on days 3 and 7 of DILS, respectively. Taken together, ONOO– can be considered a novel pro-senescence regulator that fine-tunes the redox environment for selective bio-target nitration. Thus, DILS-triggered nitrative changes at RNA and protein levels promote developmental shifts during the plant's lifespan and temporal adjustment in plant metabolism under suboptimal environmental conditions. [ABSTRACT FROM AUTHOR]

Objective: There is an association between frailty and arterial stiffness. However, arterial stiffness does not uniformly correlate with the spectrum of frailty states. Both oxidative stress and inflammaging contribute to vascular ageing. There are no human studies exploring links between arterial stiffness, oxidative stress, inflammaging and frailty. Our objective is to investigate arterial stiffness and inflammaging as predictors of frailty states. Methods: An observational longitudinal cohort study will be used to examine the association between arterial stiffness, oxidative stress and inflammation in 50 older adults (⩾70 years) with clinical frailty scores (CFS) ⩽6 over 6 months. All study measurements will be taken at baseline. Frailty assessment will include hand-grip strength, timed-up and go test, mini-mental state examination, geriatric depression scale and sarcopenia using body composition measurements with Tanita®. Arterial stiffness measurements will include carotid-femoral pulse wave velocity (cfPWV) and carotid-radial pulse wave velocity (crPWV) using Complior (Alam Medical, France). CAVI device will measure Cardio-ankle vascular index and ankle brachial index (ABI). Oxidative stress blood markers nitrotyrosine (NT) and 8-hydroxy-2'-deoxyguanosin (8-oxo-dG) and inflammation markers high-sensitive C-reactive protein (hs-CRP) and interlukin-6(IL-6) will be measured at baseline and 6 month along with lipid profile and glycated haemoglobin. Results (data analysis plan): Descriptive statistics for continuous data using means and standard deviations for normality distributed variables or medians and inter-quartile ranges for skewed variables will be used. Participants will be categorised into CFS 1-3, and CFS 4-6. Categorical data will use frequencies and comparison between groups. Change in frailty between the groups over 6 months will be compared using paired t-test. Simple linear regression will be done between frailty measures, arterial stiffness, inflammation and oxidative stress biomarkers. Significance will be at P <.05. Conclusion: This study data will inform a larger, multi-centre study exploring further the interplay between frailty, biomarkers and arterial stiffness parameters. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 negatively affects semen characteristics, impairs various biochemical processes in seminal fluid and within spermatogenic cells ultimately leading to male fertility decline. However, the distinct mechanisms, in particular, the role of oxidative stress on the consequences of coronavirus infection, have not been well investigated, which is the purpose of the present study. The standard semen parameters, its pro- and antioxidant system state, as well as the level of sperm DNA fragmentation, were assessed in 17 semen samples of men five months after the coronavirus infection and in 22 age-matched control patients. We determined that the DNA fragmentation rate negatively correlated with the period after coronavirus recovery, as well as seminal fluid superoxide dismutase activity and uric acid level. It was demonstrated that COVID-19 is not always associated with increased DNA fragmentation, allowing them to be considered as two independent factors. Thus, the most significant changes were noted in the samples of men after COVID-19 and abnormal TUNEL results: increased round cell number, decreased seminal fluid's nitrotyrosine level, and total antioxidant capacity and Zn, as well as an increased 8-hydroxy-2′-deoxyguanosine level within spermatozoa. The data obtained indicate that increased DNA fragmentation and diminished semen quality in men can be the result of an imbalance in semen pro- and antioxidant components after COVID-19. [ABSTRACT FROM AUTHOR]

Diffuse large B-cell lymphoma (DLBCL) is an aggressive B-cell lymphoma characterized by distinct subtypes and heterogeneous treatment outcomes. Oxidative stress and the dysregulation of related regulatory genes are prevalent in DLBCL, prompting an investigation into the nuclear factor erythroid 2-related factor 2 (Nrf2)-kelch-like ECH-associated protein 1 (Keap1) signaling pathway and associated genes. The present study assessed pathological specimens and clinical data from 43 newly diagnosed patients with DLBCL, comparing the associations and correlations between the expression of Nrf2, Keap1, microtubule-associated protein 1 light chain 3β (LC3B) and nitrotyrosine and the activated B-cell (ABC) and germinal center B-cell (GCB) subtypes of DLBCL using immunohistochemistry and digital image analysis software. Nuclear Nrf2 activation was observed in 33.3% of patients with DLBCL ABC, demonstrating a higher prevalence of hepatitis B surface antigen positivity, calcium ions and significant body weight loss (P<0.05). Total Nrf2 expression was associated with the DLBCL GCB subtype and inversely correlated with Keap1 expression in the DLBCL ABC subtype. Furthermore, a positive correlation was demonstrated between Nrf2 and LC3, indicating that total Nrf2 is inhibited by Keap1 and regulates LC3 expression. The ABC subtype was also associated with lower white blood cell counts and more frequent chemotherapy courses than the GCB subtype. These findings suggest that nuclear Nrf2 could be a biomarker for DLBCL clinical diagnosis., Competing Interests: The authors declare that they have no competing interests., (Copyright: © 2024 Hsu et al.)

Thyroid hormones play an important morphogenetic role during the fetal and neonatal periods and regulate numerous metabolic processes. In the central nervous system, they control myelination and overall brain development, regional gene expression, and regulation of oxygen consumption. Their deficiency in the fetal and neonatal periods causes severe mental retardation, due to lack of thyroid function, or to iodine deficiency. At the same time, nitric oxide is an atypical neurotransmitter that also has special relevance in neuronal development and plasticity and functions as a vasodilator, regulating cerebral blood flow. Although under physiological conditions it functions as a neuroprotector, in excess it can be neurotoxic. We have studied, by immunocytochemical and Western blot techniques, the evolution of the expression of neuronal and inducible isoforms of the enzyme nitric oxide synthase, and of nitrotyrosine as a marker of protein nitration produced by the presence of nitric oxide, during the early stages of postnatal brain development. We induced hypothyroidism by administering mercaptomethylimidazole to pregnant mothers, from the seventh day of gestation until the sacrifice of the offspring. The results show a delay in the evolution of the expression of the two isoforms of the enzyme nitric oxide synthase in hypothyroid animals, followed by an anomalous overexpression in later stages. Finally, the expression of nitrotyrosine follows an evolution that is synchronized with that shown by both isoenzymes in control and hypothyroid animals., Competing Interests: 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 © 2024. Published by Elsevier Inc.)

Barbara Choroma&nacute;ska,1 Piotr My&sacute;liwiec,1 Tomasz Koz&lstrok;owski,1 Magdalena &Lstrok;uba,1 Piotr Wojskowicz,1 Jacek Dadan,1 Hanna My&sacute;liwiec,2 Katarzyna Choroma&nacute;ska,3 Katarzyna Makarewicz,4 Anna Zalewska,5 Mateusz Maciejczyk6 1 1st Department of General and Endocrine Surgery, Medical University of Bialystok, Bialystok, Poland; 2Department of Dermatology and Venereology, Medical University of Bialystok, Bialystok, Poland; 3Department of Oral Surgery, Medical University of Gdansk, Gdansk, Poland; 4Regional Centre for Transfusion Medicine in Bialystok, Bialystok, Poland; 5Experimental Dentistry Laboratory, Medical University of Bialystok, Bialystok, Poland; 6Department of Hygiene, Epidemiology and Ergonomics, Medical University of Bialystok, Bialystok, PolandCorrespondence: Mateusz Maciejczyk Email mat.maciejczyk@gmail.comBackground: Adrenal masses are the most common of all human tumors. The role of nitrosative stress and inflammation in cancer development has already been demonstrated. However, it is not known whether they are involved in the pathogenesis of adrenal tumors. The aim of the study was to investigate a cross-talk between nitrosative stress, inflammation and hypoxia-inducible factor (HIF-1α) in 75 patients with different types of adrenal masses (non-functional incidentaloma, pheochromocytoma and Cushing’s/Conn’s adenoma).Methods: The plasma concentrations of total nitric oxide (NO), S-nitrosothiols, peroxynitrite nitrotyrosine and the activity of serum myeloperoxidase (MPO) were measured spectrophotometrically, whereas concentrations of interleukin 1 beta (IL-1β), tumor necrosis factor α (TNF-α) and hypoxia-inducible factor 1 alpha (HIF-1α) were measured using commercial ELISA kits. The control group consisted of 50 healthy people matched by age and sex to the study group. The number of subjects was determined a priori based on our previous experiment (power of the test = 0.9; α = 0.05).Results: We found significantly higher nitrosative stress (↑nitric oxide, ↑peroxynitrite, ↑S-nitrosothiols and ↑nitrotyrosine) in the plasma of patients with adrenal tumors, which was accompanied by increased inflammatory (↑myeloperoxidase, ↑interleukin 1 beta and ↑tumor necrosis factor α) and hypoxia (HIF-1α) biomarkers. Peroxynitrite and nitrotyrosine were positively correlated with aldosterone level. Nitrosative stress was also associated with inflammation and HIF-1α. Interestingly, plasma nitrotyrosine and serum MPO differentiated patients with adrenal tumor from healthy individuals with high sensitivity and specificity. Moreover, using multivariate regression analysis, we showed that ONOO− and IL-1β depended on cortisol level, while ONOO−, nitrotyrosine and HIF-1α were associated with aldosterone. Unfortunately, none of the assessed biomarkers differentiated between tumor types studied, suggesting that the severity of nitrosative damage and inflammation are similar in patients with incidentaloma, pheochromocytoma, and Cushing’s or Conn’s adenoma.Conclusion: Adrenal tumors are associated with increased protein nitration/S-nitrosylation and inflammation.Keywords: adrenal tumors, nitrosative stress, nitric oxide, peroxynitrite, S-nitrosothiols, nitrotyrosine, myeloperoxidase, interleukin 1 beta, tumor necrosis factor, α hypoxia-inducible factor

Objective: Background: The main cause of death among patients with malignant hypertension is a kidney failure. The promising field in essential and malignant hypertension therapy could be centered on the amelioration of oxidative stress using antioxidant molecules like resveratrol. Resveratrol is a potent antioxidative agent naturally occurred in many plants that possess health-promoting properties. Methods: In the present study, we investigated the therapeutic potential of resveratrol, a polyphenol with anti-oxidative activity, in NG-L-Arginine Methyl Ester (L-NAME) treated spontaneously hypertensive rats (SHR) - malignantly hypertensive rats (MHR). Results: Resveratrol significantly improves oxidative damages by modulation of antioxidant enzymes and suppression of prooxidant factors in the kidney tissue of MHR. Enhanced antioxidant defense in the kidney improves renal function and ameliorates the morphological changes in this target organ. Besides, protective properties of resveratrol are followed by the restoration of the nitrogen oxide (NO) pathway. 4) Conclusion: Antioxidant therapy with resveratrol could represent promising therapeutical approach in hypertension, especially malignant, against kidney damage.

3‐Nitrotyrosine (NT) is generated by the action of peroxynitrite and other reactive nitrogen species (RNS), and as a consequence it is accumulated in inflammation‐associated conditions. This is particularly relevant in kidney disease, where NT concentration in blood is considerably high. Therefore, NT is a crucial biomarker of renal damage, although it has been underestimated in clinical diagnosis due to the lack of an appropriate sensing method. Herein we report the first fluorescent supramolecular sensor for such a relevant compound: Fluorescence by rotational restriction of tetraphenylethenes (TPE) in a covalent cage is selectively quenched in human blood serum by 3‐nitrotyrosine (NT) that binds to the cage with high affinity, allowing a limit of detection within the reported physiological concentrations of NT in chronic kidney disease. [ABSTRACT FROM AUTHOR]

Gas-phase ozone (O3) and nitrogen dioxide (NO2) can react with environmentally exposed proteins to induce chemical modifications such as the formation of nitrotyrosine (NTyr). Certain proteins with these modifications have also been shown to promote adverse health effects and can trigger an immune response. It is hypothesized that proteinaceous material suspended in the atmosphere as particulate matter, e.g., embedded in pollen, can undergo heterogenous reactions to produce chemically modified proteins that impact human health, especially in urban areas. To investigate the protein modification process under ambient outdoor reaction conditions, bovine serum albumin (BSA) protein samples were loaded onto filters and exposed to urban air in Denver, Colorado (USA). Losses and measurement artifacts were measured independently to calculate nitration effects on the protein via high-performance liquid chromatography and to support the experimental methodology. O3 loss from inlet lines using three commonly used particulate filters was quantified, showing a range of ambient O3 concentration losses from 3.2% for Kynar® (polyvinylidene fluoride) filters to > 60% for commonly used HEPA filters. Protein mass extraction efficiency was calculated as a function of filter material and protein mass using both native and nitrated BSA. Finally, we show examples of BSA samples nitrated by exposure to urban air as a proof-of-concept for future studies, highlighting the potential for atmospherically relevant NTyr formation. The methodology vetted here provides support for a wide variety of experimental efforts related to exposure of analytes to O3 and more broadly to an expanding field of protein modification in ambient air. [ABSTRACT FROM AUTHOR]

Hydrangea macrophylla (Thunb.) Ser. and H. serrata (Thunb.) Ser. are popular and commercially important landscape and floriculture crops. Although both species are typically diploid, induced polyploids often exhibit horticulturally valuable traits. Procedures for inducing polyploidy vary by species and often have low or inconsistent efficacy. In this study, oryzalin and nitrotyrosine were investigated as in vitro mitotic inhibitors for inducing polyploidy in H. macrophylla ‘Robert’ and H. serrata ‘MAK20’. First, shoot apices of ‘MAK20’ were treated with 15 μm oryzalin for 0, 2, 4, 6, or 8 days, and the ploidy of shoots was determined after 8 weeks. A regression analysis showed that the proportion of polyploids (tetraploid plus mixoploid shoots) increased with the exposure duration. During a follow-up experiment, ‘MAK20’ and ‘Robert’ were treated with oryzalin (0 or 15 μm) and nitrotyrosine (0, 25, 50, and 100 µm for ‘MAK20’ and 0, 12.5, 25, 50, and 100 µm for ‘Robert’) in a factorial treatment arrangement. Oryzalin, nitrotyrosine, and their interaction influenced polyploid frequency for ‘Robert’, whereby the combination of oryzalin (15 μm) and nitrotyrosine (50 μm) resulted in the highest polyploid induction of 50%. Oryzalin influenced polyploid frequency for ‘MAK20’ ( ¯¯¯¯¯ X = 30.4%), but not nitrotyrosine or the interaction between nitrotyrosine and oryzalin. Morphology and pollen germination of these autotetraploid ‘Robert’, ‘MAK20’, and previously developed autotetraploid H. macrophylla ‘David Ramsey’ plants were compared with their diploid counterparts 1 year after plants were moved ex vitro. Compared with diploids, tetraploid hydrangeas had larger leaves, thicker stems, lower leaf area/fresh weight ratios, and longer internodes. Although all tetraploids exhibited fewer inflorescences per plant, both H. macrophylla cultivars had larger inflorescence diameters and ‘David Ramsey’ had a greater number of showy florets (sterile florets with enlarged, decorative sepals) per inflorescence. Sepal colors were compared using International Commission on Illumination L*a*b* color space. Tetraploid ‘MAK20’ had lower L* values (darker sepals), and tetraploid ‘Robert’ and ‘MAK20’ both had higher a* values (redder sepals). Pollen germination rates were greatly reduced in all tetraploid lines, but they retained some viability. These results provide an effective protocol for in vitro polyploid induction of Hydrangea sp. and documented certain desirable traits associated with tetraploid phenotypes.

The vegetal polyphenol curcumin displays beneficial effects against skeletal muscle derangement induced by oxidative stress, disuse or aging. Since oxidative stress and inflammation are involved in the progression of muscle dystrophy, the effects of curcumin administration were investigated in the diaphragm of mdx mice injected intraperitoneally or subcutaneously with curcumin for 4–12–24 weeks. Curcumin treatment independently of the way and duration of administration (i) ameliorated myofiber maturation index without affecting myofiber necrosis, inflammation and degree of fibrosis; (ii) counteracted the decrease in type 2X and 2B fiber percentage; (iii) increased about 30% both twitch and tetanic tensions of diaphragm strips; (iv) reduced myosin nitrotyrosination and tropomyosin oxidation; (v) acted on two opposite nNOS regulators by decreasing active AMP-Kinase and increasing SERCA1 protein levels, the latter effect being detectable also in myotube cultures from mdx satellite cells. Interestingly, increased contractility, decreased myosin nitrotyrosination and SERCA1 upregulation were also detectable in the mdx diaphragm after a 4-week administration of the NOS inhibitor 7-Nitroindazole, and were not improved further by a combined treatment. In conclusion, curcumin has beneficial effects on the dystrophic muscle, mechanistically acting for the containment of a deregulated nNOS activity.

Oxidative stress is proposed in the literature as an important player in the development of CHF and correlates with left ventricle (LV) dysfunction and hypertrophy in the failing heart. In this study, we aimed to verify if the serum oxidative stress markers differ in chronic heart failure (CHF) patients’ groups depending on the LV geometry and function. Patients were stratified into two groups according to left ventricular ejection fraction (LVEF) values: HFrEF (n = 27)) and HFpEF (≥40% (n = 33)). Additionally, patients were stratified into four groups according to LV geometry: NG–normal left ventricle geometry (n = 7), CR–concentric remodeling (n = 14), cLVH–concentric LV hypertrophy (n = 16), and eLVF–eccentric LV hypertrophy (n = 23). We measured protein (protein carbonyl (PC), nitrotyrosine (NT-Tyr), dityrosine), lipid (malondialdehyde (MDA), oxidizes (HDL) oxidation and antioxidant (catalase activity, total plasma antioxidant capacity (TAC) markers in serum. Transthoracic echocardiogram analysis and lipidogram were also performed. We found that oxidative (NT-Tyr, dityrosine, PC, MDA, oxHDL) and antioxidative (TAC, catalase) stress marker levels did not differ between the groups according to LVEF or LV geometry. NT-Tyr correlated with PC (rs = 0.482, p = 0.000098), and oxHDL (rs = 0.278, p = 0.0314). MDA correlated with total (rs = 0.337, p = 0.008), LDL (rs = 0.295, p = 0.022) and non-HDL (rs = 0.301, p = 0.019) cholesterol. NT-Tyr negatively correlated with HDL cholesterol (rs = -0.285, p = 0.027). LV parameters did not correlate with oxidative/antioxidative stress markers. Significant negative correlations were found between the end-diastolic volume of the LV and the end-systolic volume of the LV and HDL-cholesterol (rs = –0.935, p < 0.0001; rs = –0.906, p < 0.0001, respectively). Significant positive correlations between both the thickness of the interventricular septum and the thickness of the LV wall and the levels of triacylglycerol in serum (rs = 0.346, p = 0.007; rs = 0.329, p = 0.010, respectively) were found. In conclusions, we did not find a difference in serum concentrations of both oxidant (NT-Tyr, PC, MDA) and antioxidant (TAC and catalase) concentrations in CHF patients’ groups according to LV function and geometry was found. The geometry of the LV could be related to lipid metabolism in CHF patients, and no correlation between oxidative/antioxidant and LV markers in CHF patients was found.

Diabetes mellitus (DM) is a strong risk factor for the development of cardiovascular diseases (CVDs), which are the most important cause of morbidity and mortality in the population of patients living with DM. DM is associated with lipid metabolism disorders characterized by a decrease in the high-density lipoprotein blood concentration, an increase in the triglyceride blood concentration, and the presence of modified lipoproteins not routinely measured in clinical practice. Nitrated lipoproteins are produced by the nitration of the tyrosyl residues of apolipoproteins by myeloperoxidase. There is some evidence from the research conducted showing that nitrated lipoproteins may play a role in the development of cardiovascular dysfunction, but this issue requires further investigation. It was found that the nitration of HDL particles was associated with a decrease in caspase-3 and paraoxonase-1 activity, as well as a decrease in the activity of cholesterol transport via ABCA1, which reduces the protective effect of HDL particles on the cardiovascular system. Less information has been collected about the role of nitrated LDL particles. Thus far, much more information has been obtained on the relationship of nitrotyrosine expression with the presence of cardiovascular risk factors and the development of cardiovascular dysfunction. The purpose of this paper is to provide an extensive review of the literature and to present the most important information on the current state of knowledge on the association between nitrotyrosine and nitrated lipoproteins with dysfunction of the cardiovascular system, especially in patients living with DM. Moreover, directions for future research in this area were discussed. [ABSTRACT FROM AUTHOR]

The infection with SARS-CoV-2 impairs the glucose–insulin axis and this contributes to oxidative (OS) and nitrosative (NSS) stress. Here, we evaluated changes in glucose metabolism that could promote the loss of redox homeostasis in COVID-19 patients. This was comparative cohort and analytical study that compared COVID-19 patients and healthy subjects. The study population consisted of 61 COVID-19 patients with and without comorbidities and 25 healthy subjects (HS). In all subjects the plasma glucose, insulin, 8-isoprostane, Vitamin D, H2S and 3-nitrotyrosine were determined by ELISA. The nitrites (NO2−), lipid-peroxidation (LPO), total-antioxidant-capacity (TAC), thiols, glutathione (GSH) and selenium (Se) were determined by spectrophotometry. The glucose, insulin and HOMA-IR (p < 0.001), 8-isoprostanes, 3-nitrotyrosine (p < 0.001) and LPO were increased (p = 0.02) while Vitamin D (p = 0.01), H2S, thiols, TAC, GSH and Se (p < 0.001) decreased in COVID-19 patients in comparison to HS. The SARS-CoV-2 infection resulted in alterations in the glucose–insulin axis that led to hyperglycemia, hyperinsulinemia and IR in patients with and without comorbidities. These alterations increase OS and NSS reflected in increases or decreases in some oxidative markers in plasma with major impact or fatal consequences in patients that course with metabolic syndrome. Moreover, subjects without comorbidities could have long-term alterations in the redox homeostasis after infection. [ABSTRACT FROM AUTHOR]

Abstract Background Endothelial function is dependent on the balance between vasoconstrictive and vasodilatory substances. The endothelium ability to produce nitric oxide is one of the most crucial mechanisms in regulating vascular tone. An increase in inducible nitric oxide synthase contributes to endothelial dysfunction in overweight persons, while oxidative stress contributes to the conversion of nitric oxide to peroxynitrite (measured as nitrotyrosine in vivo) in underweight persons. The objective of this study was to elucidate the interaction of body composition and oxidative stress on vascular function and peroxynitrite. This was done through an experimental design with three weight groups (underweight, normal weight and overweight), with four treatment arms in each. Plasma nitrotyrosine levels were measured 15–20 h post lipopolysaccharide (LPS) treatment, as were aortic ring tension changes. Acetylcholine (ACh) and sodium nitroprusside (SNP) challenges were used to observe endothelial-dependent and endothelial-independent vascular relaxation after pre-constriction of aortic rings with phenylephrine. Results Nitrotyrosine levels in saline-treated rats were similar among the weight groups. There was a significant increase in nitrotyrosine levels between saline-treated rats and those treated with the highest lipopolysaccharide doses in each of the weight groups. In response to ACh challenge, R max (percentage reduction in aortic tension) was lowest in overweight rats (112%). In response to SNP, there was an insignificantly lower R max in the underweight rats (106%) compared to the normal weight rats (112%). Overweight rats had a significant decrease in R max (83%) in response to SNP, signifying involvement of a more chronic process in tension reduction changes. A lower R max accompanied an increase in peroxynitrite after acetylcholine challenge in all weight groups. Conclusions Endothelial dysfunction, observed as an impairment in the ability to reduce tension, is associated with increased plasma peroxynitrite levels across the spectrum of body mass. In higher-BMI rats, an additional role is played by vascular smooth muscle in the causation of endothelial dysfunction.

Background and purpose: Paracetamol is the most implicated xenobiotic in inducing hepatotoxicity. Our study aimed to determine the impact of some kaempferol glycosides isolated from the leaves of Cedrela odorata L. on paracetamol hepatotoxicity. Experimental approach: The methanolic extract of dried leaves of C. odorata L. was subjected to the combination of spectroscopic methods (1H and 13CNMR). Six kaempferol glycosides were isolated: kaempferol-3-O-β-D-glycopyranoside (astragalin), kaempferol-3-O-β-L-rhamnopyranoside, kaempferol-3-O-β-D-rutinoside, kaempferide-3-O-β-D-rutinoside, kaempferide-3-O-β-Drutinosyl-7-O-β-D-rhamnopyranoside, and kaempferol-3-O-β-D- rutinosyl-7-O-a-D-arabinopyranoside. Fifty-four female Swiss Albino mice were divided randomly into 9 groups including[1] control negative (1 mL/kg saline; IP),[2] control positive (paracetamol 300 mg/kg; IP),[3] silymarin 50 mg/kg (IP). Animals of groups 4-9 were injected with 6 different samples of isolated compounds at 100 mg/kg (IP). One h later, groups 3-9 were injected with paracetamol (300 mg/kg IP). Two h later, tissue samples were taken from all animals to assess nitrotyrosine, c-Jun N-terminal protein kinase (c-JNK), Raf -1kinase, and oxidative stress biomarkers viz. reduced glutathione (GSH) and malondialdehyde (MDA). Findings/Results: Isolated glycosides had a prominent anti-apoptotic effect via inhibition of c-JNK and Raf-1 kinase. They also exerted a powerful antioxidant effect by modulating the oxidative stress induced by paracetamol via increasing GSH, reducing MDA and nitrotyrosine concentrations compared to positive control. The glycoside[1] showed a better effect than silymarin (standard) in ameliorating the formation of nitrotyrosine, Raf-1 kinase, c-JNK, and GSH. Conclusion and implication: Kaempferol glycosides isolated for the first time from C. odorata L. leaves exerted antioxidant and antiapoptotic effects via amelioration of oxidative stress and inhibition of Raf/ MAPK pathway.

The objective: to investigate the impact of anesthesia method on the severity of oxidative stress in patients after coronary artery bypass grafting with cardiopulmonary bypass.Subjects and methods. Patients were randomized (seed 6556 as of 04.01.2016, www.randomization.com) to Volatile Induction and Maintenance Anesthesia (VIMA) with Sevoflurane group (n = 65) and Total Intravenous Anesthesia with Propofol and Fentanyl (TIVA) group (n = 66). The changes in oxidative stress markers in blood plasma were studied: carbonylated proteins, nitrotyrosine, oxidized forms of low-density lipoproteins – oxy-LDL.Results. At the critical stage with 24 hours after the surgery, statistically significant differences in the carbonyls blood levels were found between VIMA with Sevoflurane and TIVA with Propofol groups: 0.88 (0.79–0.96) nmol/mg protein (nmol/mg) in TIVA group vs 0.81 (0.75–0.91) nmol/mg in VIMA group, p = 0.01; and oxy-LDL levels 0.96 ± 0.40 mg/ml vs 0.83 ± 0.33 mg/ml, respectively, p = 0.04. Nitrotyrosine demonstrated no diagnostic value.Conclusion. It has been suggested that sevoflurane possesses antioxidant properties that can be regarded as a positive quality of VIMA in coronary artery bypass grafting with cardiopulmonary bypass.

The diffusion-limited reaction of nitric oxide (NO) and superoxide (O2−) produces peroxynitrite (ONOO−), a biological oxidant that has been implicated in a number of pathological conditions, including neurodegenerative disorders. We previously reported that incubation of PC12 cells with peroxynitrite triggers apoptosis by simultaneously inhibiting the PI3K/Akt survival pathway, and activating the p38 and JNK MAP kinase pathways. We also reported that peroxynitrite-treated Heat Shock Protein 90 (Hsp90) stimulates PC12 cell death. Here, we show that nitrated Hsp90 mediates peroxynitrite-induced apoptosis by regulating specific signaling pathways triggered by activation of the purine receptor P2X7 (P2X7R) and downstream activation of PTEN. Intracellular delivery of peroxynitrite-treated Hsp90 was sufficient to stimulate PC12 cell death. In contrast, intracellular delivery of peroxynitrite-treated Hsp90 in which the five tyrosine (Tyr) residues susceptible to nitration were replaced by nitration-resistant phenylalanine had no effect on PC12 cell survival. Further, only nitration of Hsp90 at Tyr 56 was necessary and sufficient to stimulate PC12 cell apoptosis, and incubation of PC12 cells with peroxynitrite resulted in Hsp90 nitration at Tyr 56. Inhibition of P2X7R or downstream inhibition of PTEN prevented PC12 cell death stimulated by both incubation with peroxynitrite and nitrated Hsp90 (Hsp90NY). Peroxynitrite, Hsp90NY, and P2X7R activation all increased p38 and JNK MAP kinases activity, while inhibiting the Akt survival pathway. These results suggest that, in undifferentiated PC12 cells, peroxynitrite triggers apoptosis via nitration of Hsp90 at Tyr 56, which in turn activates P2X7R and PTEN. These results contrast with observations in motor neurons where the nitration of either Tyr 33 or Tyr 56 in Hsp90 stimulates apoptosis, suggesting that the targets of peroxynitrite may be different in different cell types. However, uncovering the pathways through which peroxynitrite triggers cell death in neurodegenerative conditions will provide new potential targets for therapeutic treatment.

Protein nitrotyrosine is an essential post-translational modification that results from the nitration of tyrosine amino acid residues. This modification is known to be associated with the regulation and characterization of several biological functions and diseases. Therefore, accurate identification of nitrotyrosine sites plays a significant role in the elucidating progress of associated biological signs. In this regard, we reported an accurate computational tool known as iNTyro-Stack for the identification of protein nitrotyrosine sites. iNTyro-Stack is a machine-learning model based on a stacking algorithm. The base classifiers in stacking are selected based on the highest performance. The feature map employed is a linear combination of the amino composition encoding schemes, including the composition of k-spaced amino acid pairs and tri-peptide composition. The recursive feature elimination technique is used for significant feature selection. The performance of the proposed method is evaluated using k-fold cross-validation and independent testing approaches. iNTyro-Stack achieved an accuracy of 86.3% and a Matthews correlation coefficient (MCC) of 72.6% in cross-validation. Its generalization capability was further validated on an imbalanced independent test set, where it attained an accuracy of 69.32%. iNTyro-Stack outperforms existing state-of-the-art methods across both evaluation techniques. The github repository is create to reproduce the method and results of iNTyro-Stack, accessible on: https://github.com/waleed551/iNTyro-Stack/., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest related to this research., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

γ-Tocopherol (γT) is a major form of vitamin E in the US diet and the second most abundant vitamin E in the blood and tissues, while α-tocopherol (αT) is the predominant vitamin E in tissues. During the last >25 years, research has revealed that γT has unique antioxidant and anti-inflammatory activities relevant to disease prevention compared to αT. While both compounds are potent lipophilic antioxidants, γT but not αT can trap reactive nitrogen species by forming 5-nitro-γT, and appears to show superior protection of mitochondrial function. γT inhibits ionophore-stimulated leukotrienes by blocking 5-lipoxygenase (5-LOX) translocation in leukocytes, decreases cyclooxygenase-2 (COX-2)-catalyzed prostaglandins in macrophages and blocks the growth of cancer cells but not healthy cells. For these activities, γT is stronger than αT. Moreover, γT is more extensively metabolized than αT via cytochrome P-450 (CYP4F2)-initiated side-chain oxidation, which leads to formation of metabolites including 13′-carboxychromanol (13′-COOH) and carboxyethyl-hydroxychroman (γ-CEHC). 13′-COOH and γ-CEHC are shown to be the predominant metabolites found in feces and urine, respectively. Interestingly, γ-CEHC has natriuretic activity and 13′-COOH inhibits both COX-1/-2 and 5-LOX activity. Consistent with these mechanistic findings of γT and metabolites, studies show that supplementation of γT mitigates inflammation and disease symptoms in animal models with induced inflammation, asthma and cancer. In addition, supplementation of γT decreased inflammation markers in patients with kidney diseases and mild asthma. These observations support that γT may be useful against inflammation-associated diseases. [Display omitted] • γ-Tocopherol (γT), but not α-tocopherol (αT), can trap NOx via forming 5-nitro-γT. • γT is stronger than αT in blocking 5-lipoxygenase activation, cyclooxygenase-1-catalyzed thromboxane and anticancer. • γT's metabolite 13′-carboxychromanol is an inhibitor of cyclooxygenase-1/-2 and 5-lipoxygenase. • γT is stronger than αT in attenuating inflammation-associated damages and cancer prevention in animal models. • γT shows protective effects in patients with kidney diseases and asthma. [ABSTRACT FROM AUTHOR]

Parkinson’s disease (PD) is one of the most widespread neurodegenerative diseases. In spite of the large number of researches, the problem of earlier diagnosis and targeted pathogenetic therapy remains relevant. For more than 20 years, scientists have been continuing to study potential diagnostic and prognostic PD biomarkers. An accurate diagnostic biomarker can help identify PD before motor symptoms occur, or when motor and non-motor symptoms are insufficient to diagnose, and also can be used to differentiate between idiopathic PD and other forms of parkinsonism. The aim of the research is to analyze the last studies of potential PD biomarkers in human biological fluids. Conclusions. Most studies of recent years indicate that the level of total α-synuclein, its oligomers in blood plasma and its formed elements is elevated in patients at the early stages of PD, and it can be a valuable prognostic biomarker for disease progression, in particular its motor symptoms. Studies of the level of this potential biomarker not only in blood plasma and its formed elements, but also in neuronal exosomes, are promising. The negative impact of oxidative stress in PD is a significant trigger for irreversible pathogenetic processes that affect the development of neurodegenerative changes. Perspectives of further researches may lay not only in identifying the concentrations of nitrotyrosine and oxidative stress components and antioxidants in the blood of PD patients, but also in determining of the effect of antiparkinsonian and neuroprotective drugs on the antioxidant system in order to pathogenetically justify their use for reducing of oxidative stress. It is promising to study the activity of melatonin in the context of its relationship with the components of oxidative stress and antioxidants by determining their concentrations in blood of PD patients.

A critical step in developing therapeutics for oxidative stress-related pathologies is the ability to determine which specific modified protein species are innocuous by-products of pathology and which are causative agents. To achieve this goal, technologies are needed that can identify, characterize and quantify oxidative post translational modifications (oxPTMs). Nanobodies (Nbs) represent exquisite tools for intracellular tracking of molecules due to their small size, stability and engineerability. Here, we demonstrate that it is possible to develop a selective Nb against an oxPTM protein, with the key advance being the use of genetic code expansion (GCE) to provide an efficient source of the large quantities of high-quality, homogenous and site-specific oxPTM-containing protein needed for the Nb selection process. In this proof-of-concept study, we produce a Nb selective for a 3-nitrotyrosine (nitroTyr) modified form of the 14-3-3 signaling protein with a lesser recognition of nitroTyr in other protein contexts. This advance opens the door to the GCE-facilitated development of other anti-PTM Nbs.