Concentration Of Nitric Oxide Metabolites Research Articles

The effect of nitric oxide donation on the severity of mitochondrial disfunction to the renal tissue in cardiopulmonary bypass simulation: an experimental study

INTRODUCTION: Acute kidney injury is one of the common complications in cardiosurgical operations with cardiopulmonary bypass (CPB). A number of studies have shown that donation of exogenous nitric oxide (NO) reduces episodes of аcute kidney injury. However, subcellular mechanisms of realization the nephroprotective properties of NO remain unknown. OBJECTIVE: To study the safety of the technology of plasma-chemical synthesis of nitric oxide and to evaluate the effect of the delivery resulting nitric oxide on mitochondrial damage to the renal tissue in the simulation of cardiopulmonary bypass. MATERIALS AND METHODS: Experiment included 12 rams of the Altai breed. Animals were divided into 2 groups: 6 animals were modeled CPB; 6 animals were simulated CPB with NO delivery. Mitochondrial damage was assessed by calcium-binding capacity and transmembrane potential of mitochondria 1 h after weaning from the CPB. The safety of the NO delivery according to the proposed method was assessed by the concentration of nitrogen dioxide on inspiration, the level of methemoglobin. The efficiency of NO delivery according to the proposed method was assessed by the level of stable NO metabolites: endogenous nitrite, nitrate and total concentration of NO metabolites. RESULTS: In the group of animals with NO delivery the average level of transmembrane potential of mitochondria was (171.66 ± 20.41 vs 126.66 ± 18.61; p = 0.00256) and calcium-binding capacity of mitochondria was (1466.66 ± 216.02 vs 866.66 ± 216.02; p = 0.000712) of renal parenchyma. Methemoglobin levels above the recommended thresholds in clinical practice were not recorded in the CPB+NO group. The values of total concentration of NO metabolites and nitrate in the CPB+NO group compared to the CPB group are statistically significantly higher, p = 0.00006; p = 0.0035, respectively. CONCLUSIONS: Plasma-chemical synthesis of nitric oxide is a safe technology, and the use of the resulting nitric oxide in cardiopulmonary bypass leads to a decrease in the severity of mitochondrial dysfunction in the kidney parenchyma.

Chelation Therapy Associated with Antioxidant Supplementation Can Decrease Oxidative Stress and Inflammation in Multiple Sclerosis: Preliminary Results.

An imbalance of oxy-inflammation status has been involved in axonal damage and demyelination in multiple sclerosis (MS). The aim of this study was to investigate the efficacy of an antioxidant treatment (calcium disodium ethylenediaminetetracetic acid-EDTA) chelation therapy associated with a micronutrient complex in MS patients. A total of 20 MS patients and 20 healthy subjects, enrolled as a control group (CTR), were recruited. We measured the plasma ROS production and total antioxidant capacity (TAC) by a direct assessment using Electron Paramagnetic Resonance; activities of the antioxidant system (thiols' redox status and enzymes); and the urinary presence of biomarkers of oxidative stress by immunoenzymatic assays. We also evaluated the levels of inflammation by plasmatic cytokines (TNFα, IL-1β, and IL-6) and assessed the sICAM levels, as well as the nitric oxide (NO) catabolism and transthyretin (TTR) concentration. Comparing CTR and MS, in the latter ROS production, oxidative damage, inflammatory biomarkers, and NO metabolite concentrations results were significantly higher, while TAC was significantly lower. Treatment in MS induced significant (p < 0.05) down-regulating of pro-inflammatory sICAM1, TNF-α, IL6, as well as biomarkers of lipid peroxidation and DNA damage production. The protective effect exhibited may occur by decreasing ROS production and increasing antioxidant capacity, turning into a more reduced thiols' status.

Influence of lipopolysaccharide and the general adaptation syndrome on the development of oxidative-nitrosative stress in the lacrimal glands of rats

The lacrimal glands play a key role in the visual organ functioning due to the production of tear fluid. From a pathogenetic point of view, it is interesting to study the combined effect of the general adaptation syndrome and systemic inflammatory response syndrome (SIRS) on lacrimal glands metabolism. The purpose of this study is to assess changes in the L-arginine-dependent part of nitric oxide cycle, nitric oxide metabolites concentration, and pro- and antioxidant balance in the rat lacrimal glands during modelling of chronic stress and SIRS. The experiments were performed on 18 mature male rats weighing 190-240 g. The animals were divided into 3 groups: I – control, II – water avoidance stress (WAS) group, III – WAS rats injected with lipopolysaccharide (WAS+LPS) group. The NO cycle parameters and markers of oxidative stress were determined in the rat lacrimal glands homogenate. The superoxide anion production and malondialdehyde concentration in the lacrimal glands of WAS+LPS rats increased by 2.48 and 1.86 times, respectively, compared to the control group and by 1.35 and 1.11 times compared to WAS group. The catalase activity in WAS+LPS rats decreased by 1.68 times and superoxide dismutase activity increased by 1.34 times compared to the control group; if compared to WAS group, catalase activity increased by 1.26 times, and superoxide dismutase activity elevated by 6.52 times. The activity of inducible NO-synthase in WAS+LPS rats decreased by 1.29 times compared to the control and increased by 1.23 times compared to WAS group. The concentration of peroxynitrites, nitrites, and nitrosothiols in WAS+LPS rats increased by 2.6, 3.02, and 3.68 times, respectively, compared to the control group and by 1.43, 1.41, and 2 .91 times compared to WAS group. Thus, administration of bacterial LPS to rats under the conditions of stress modeling enhances antioxidant protection and increases nitric oxide production from iNOS; at the same time, such stimulation increases damage to protein and lipid structures.

Reduced nitric oxide synthesis in winter: A potential contributing factor to increased cardiovascular risk

BackgroundNitric oxide is a key signalling molecule that elicits a range of biological functions to maintain vascular homeostasis. A reduced availability of nitric oxide is implicated in the progression of cardiovascular diseases and increases the risk of pathogenic events. AimsTo compare the concentration of nitric oxide metabolites in healthy adults between winter and summer months. DesignAn observational study of healthy adults (age 32 ± 9 years) living in central Scotland. MethodsThirty-four healthy adults (13 females) were monitored for 7 days in summer and winter to record sunlight exposure (ultraviolet-A (UV-A) radiation), diet, and physical activity. At the end of each phase, blood pressure was measured, and samples of blood and saliva collected. The samples were analysed to determine the concentrations of plasma and salivary nitrate and nitrite and serum 25-hydroxyvitamin D (25(OH)D). ResultsThe participants maintained similar diets in each measurement phase but were exposed to more UV-A radiation (550%) and undertook more moderate-vigorous physical activity (23%) in the summer than in winter. Plasma nitrite (46%) and serum 25(OH)D (59%) were higher and blood pressure was lower in the summer compared to winter months. Plasma nitrite concentration was negatively associated with systolic, diastolic, and mean arterial blood pressure. ConclusionsPlasma nitrite, an established marker of nitric oxide synthesis, is higher in healthy adults during the summer than in winter. This may be mediated by a greater exposure to UV-A which stimulates the release of nitric oxide metabolites from skin stores. While it is possible that seasonal variation in nitric oxide availability may contribute to an increased blood pressure in the winter months, the overall impact on cardiovascular health remains to be determined.

Association analysis of single nucleotide polymorphisms in autophagy related 7 (ATG7) gene in patients with coronary artery disease.

Recent experimental studies sparked the involvement of autophagy-related 7 (ATG7) in the development of atherosclerosis. However, the genetic variants and their association with coronary artery disease (CAD) are still to be unveiled. Therefore, we aimed to design a retrospective case-control study for the analysis of ATG7 gene polymorphisms and their association with CAD among the subjects originating from Pakistan.The ATG7 noncoding polymorphisms (rs1375206; Chr3:11297643 C/G and rs550744886; Chr3:11272004 C/G) were examined in 600 subjects, including 300 individuals diagnosed with CAD. Arginase-1 (ARG1) and nitric oxide metabolites were measured by the colorimetric enzymatic assay. Genotyping of noncoding ATG7 polymorphisms was accomplished by the polymerase chain reaction–restriction fragment length polymorphism method.A significant association of ATG7 (rs1375206 and rs550744886) was observed in individuals exhibiting CAD (P < .0001, for each single-nucleotide polymorphism). Moreover, variant allele G at both loci showed high occurrence and significant association with the disease phenotype as compared to the wild-type allele (odds ratio [OR] = 2.03, P < .0001 and OR = 2.08, P < .001, respectively). Variant genotypes at ATG7 rs1375206 and rs550744886 showed significant association with high concentrations of ARG1 and low nitric oxide metabolites among the patients (P < .0001 for each). A significant difference was noted in the distribution of the haplotype G-G, mapped at Chr3:11297643-11272004 between cases and controls (P < .0001).The study concludes that ATG7 polymorphisms are among the risk factors for CAD in the subjects from Pakistan. The study thus highlights the novel risk factors for high incidents of the disease and reported for the first time to the best of our knowledge.

Poly I:C and R848 facilitate nitric oxide production via inducible nitric oxide synthase in chicks

Nitric oxide (NO) is a gaseous bioactive molecule associated with many physiological functions including vasodilation and neurotransmission. NO also plays an important role in immune responses during viral infections in mammals. However, there is a paucity of knowledge regarding the involvement of NO in viral infections in birds. Therefore, the purpose of the present study was to determine if intraperitoneal (IP) injection of poly I:C and R848 (resiquimod), which are analogues of virus component, affects NO production in chicks (Gallus gallus) as a bird model. The involvement of inducible NO synthase (iNOS) in poly I:C- and R848-induced anorexia and corticosterone release was also investigated. These virus analogues significantly increased plasma NO metabolites (NOx) concentrations. IP injection of poly I:C and R848 significantly increased iNOS mRNA expression in several organs including the liver. On the other hand, poly I:C and R848 significantly decreased mRNA expressions of endothelial NOS and neural NOS in several organs, indicating that induction of iNOS might be responsible for increased NOx levels in plasma. This finding was further confirmed by using a selective iNOS inhibitor, S-methylisothiourea sulfate (SMT), which abolished the poly I:C- and R848-induced increase in plasma NOx concentration. In addition, SMT partly attenuated the poly I:C- and R848-induced increase in plasma corticosterone concentration, suggesting that corticosterone release induced by these virus analogues may be partly mediated by iNOS. Collectively, the present results suggest that viral infections facilitate NO production by inducing iNOS. The liver would play an important role in the NO production because the response in iNOS mRNA expression to poly I:C and R848 was remarkable. The present results also suggest that NO is associated with corticosterone release in birds under viral infection.

Neuroprotective and memory enhancing effects of Zataria multiflora in lipopolysaccharide-treated rats.

The study was aimed to evaluate the effects of hydro-ethanol extract Zataria multiflora on the brain tissue oxidative damage, and hippocampal interleukin-6 (IL-6) as well as learning and memory capacity in lipopolysaccharide (LPS) - challenged rats. The rats were randomized into five groups as follow: Control group: Rats were treated with saline, LPS group: Rats were treated with LPS 1.00 mg kg-1, ZM50, ZM100 and ZM200 groups in which the rats were treated with Z. multiflora extract (50.00, 100 or 200 mg kg-1 per day, respectively). The treatments including extract or vehicle were administered intraperitoneally ‎and given three days before the behavioral tests and were continued within a6-day behavioral experiment. Injection of LPS was daily done before the behavioral tests. Finally, the brains were collected for biochemical evaluations. Although LPS administration prolonged the latency in Morris water maze and shortened the latency to enter the dark chamber in passive avoidance test, ZM extract restored these changes to approach control group values. Also, LPS increased IL-6, malondialdehyde (MDA) and nitric oxide (NO) metabolites levels and lowered thiol, superoxide dismutase (SOD) and catalase (CAT) levels in the brain, however, Z. multiflora extract reduced IL-6, MDA and NO metabolites concentrations, but increased thiol content, SOD, and CAT levels. The results of this study showed that Z. multiflora ameliorated learning and memory dysfunction in LPS - challenged rats by alleviating of inflammatory responses and brain tissue oxidative damage.

Uncovering associations between mental illness diagnosis, nitric oxide synthase gene variation, and peripheral nitric oxide concentration

Nitric oxide (NO) signalling has been implicated in the pathogenesis of several mental illnesses; however, its specific contribution remains unclear. We investigated whether peripheral NO concentration is associated with specific diagnoses, and whether there is a correlation with genetic variation in NO synthase (NOS) genes. We included 185 participants in the study; 52 healthy controls, 43 major depressive disorder (MDD) patients, 41 bipolar disorder (BPD) patients, and 49 schizophrenia (SCZ) patients. Clinical, genetic, and biochemical data were collected at admission to a psychiatric hospital and at discharge. Serum was used to quantify concentration of the stable NO metabolites nitrite and nitrate. Individuals were genotyped for the NOS1 exon 1f variable number of tandem repeats 1 (VNTR1) polymorphism, and single nucleotide polymorphisms (SNPs) in the NOS1, NOS1AP and NOS3 genes. At admission, SCZ patients were found to have significantly higher peripheral NO metabolite (NOx-) concentrations compared to healthy controls, MDD and BPD patients. NOS1 exon 1f VNTR1 short allele carriers were found to have significantly increased NOx- concentration. Moreover, this result was still significant in patients even at discharge. The data also revealed that patients who did not remit in their depressive symptoms had significantly increased NOx- concentration compared to remitters at discharge, supported by the finding of a significant positive correlation between depression symptom severity and NOx- concentration. Taken together, it is possible that elevated peripheral NOx- concentration is associated with increased severity of psychopathology, potentially due to NOS1 exon1f VNTR1 genotype. Our results further implicate NO signalling in mental illness pathogenesis, supporting its possible use as a peripheral biomarker, and imply that NOS genotype may play a significant role in regulating peripheral NOx- concentration.

Associations of circulating biomarkers with the presence and severity of coronary, carotid and femoral arterial atherosclerosis

Aim. To identify and characterize the associations of the presence and severity of atherosclerosis of various localization with the blood level of biochemical parameters, as well as to assess the potential of their use as markers of metabolic disorders with increased atherogenic potential.Material and methods. The study included 216 patients (men, 53%) aged 24-87 years (mean age, 61,5±10,73 years). All patients underwent coronary angiography, carotid (CA) and femoral arterial (FA) duplex ultrasound to assess the presence and severity of atherosclerosis. In blood serum/plasma, biochemical parameters were analyzed using standard methods.Results. Based on the analysis of circulating biomarker profile, diagnostic complexes have been established that allow assessing atherosclerosis of different localization. According to the data obtained, the determinants of coronary and CA atherosclerosis are endothelial dysfunction (concentration of nitric oxide metabolites &lt;36,0 μmol/L) and an increased level of creatinine (≥73,0 μmol/L). The specific markers associated with severe atherosclerosis of coronary and FAs (but not CA) were low high-density lipoprotein cholesterol (≤1,0/1,2 μmol/L for male/ female, respectively) and an increased C-reactive protein level (≥1,0 mg/l). Severe peripheral atherosclerosis (CA and FA involvement) was associated with hyperglycemia (glucose ≥6,1 μmol/L), while severe FA atherosclerosis — with hyperinsulinemia (insulin ≥14,0 μU/ml).Conclusion. The analysis of associations of circulating biochemical parameters with atherosclerosis localization and severity revealed a number of metabolic markers associated with the increased atherogenic potential. It is possible to distinguish both universal parameters that are associated with atherosclerosis, regardless of its localization and/or severity, and specific biomarkers that characterize either the localization or the severity of atherosclerosis, or both.

Oxidative stress in suyagny sheep at the end of gestation, as a factor in pathogenesis development of eclampsia

Analysis of the results of medical examination of pregnant sheep 30...15...5 days before the expected term of lambing showed that in the urine of 12.11% of ewes, the concentration of ketone bodies in the blood plasma was 1.43 times higher than the physiological norm. In addition, there is a tendency to decrease the buffer bases to 18.41±1.53 mmol/l, as well as the glucose content below 2.12 ± 0.12 mmol/l. At the same time, the ratio of VN/ ACAS is up to 1.47 ± 0.12 mmol / L. It was found that the albumin fraction of proteins decreased by 1.51 times. Edema in the abdominal wall and underbelly, 9.5% lack of reaction to external stimuli, 15.0% decreased appetite, 10.0% jaundice of mucous membranes and 9.0% of sheep had a comatose state were found in 15.0% of animals. In a clinical study in sheep with eclampsia, hypertension over 136.1 mmHg and the presence of protein in urine over 3.2 g/l were recorded. These symptoms indicated classic signs of eclampsia, which occurred depending on the condition of sick animals in atypical and typical forms of manifestation. In animals with typical clinical signs of eclampsia, an increase in the level of diene conjugates was found to be 1.87 times, and the concentration of ketodiene intermediates and conjugated trienes was 1.75 times, the concentration of stable nitric oxide metabolites was 38.0%, and the vitamin E content decreased by 13.1%. At the same time, there was a 20.46% increase in the concentration of double bonds in the atypical form of eclampsia. In the blood plasma of patients with eclampsia of pregnant ewes, the activity of superoxide dismutase (1,736±0.37 units) is lower than in the comparison group (2,146±0.56 mmol/l). The obtained material of this work should be taken into account in the future when studying the problem of complicated pregnancy in the last stages of gestation in sheep and when developing therapeutic and preventive measures to ensure the long-term functioning of the reproductive potential and obtaining a viable newborn offspring.

A high single oral dose of turmeric extract (Curcuma longa L.) does not improve skeletal muscle microvascular reactivity in older subjects

Increased production of reactive oxygen species reduces nitric oxide (NO) bioavailability and impairs vascular function with aging. Curcumin is a polyphenolic compound found in the rhizome of turmeric (Curcuma longa) with antioxidant properties. An increasing number of studies have demonstrated improvement in the vasodilatory response of conduit arteries following curcumin supplementation, which has been associated with increased NO production. However, less is known about the effects of curcumin on resistance vessels response. Therefore, the present study aimed to investigate the effects of a high single dose of turmeric extract on skeletal muscle microvascular reactivity and plasma concentrations of NO metabolites in older adults. Twenty-one older adults consumed 10 g of turmeric extract (CUR) or placebo (PLA) in a randomized, double-blind, and crossover design. Blood samples were drawn to assay NO metabolites (NO2− and NO3−), and changes in oxygen saturation parameters following arterial occlusion were used to evaluate microvascular reactivity. There were no significant changes in plasma concentrations of NO2− and NO3− as well the parameters of oxygen saturation were not affected after CUR. In conclusion, a high single dose of turmeric extract does not affect the plasma concentration of NO metabolites nor skeletal muscle microvascular reactivity in older adults.

Dysregulated Arginine Metabolism in Young Patients with Chronic Persistent Asthma and in Human Bronchial Epithelial Cells.

Background: Recent metabolomics studies have found circulatory metabolism alterations in patients with asthma, indicating that altered metabolites played a significant role in asthma. However, the regulatory mechanisms in asthma, especially in young chronic persistent asthma remain underexplored. Methods: In this study, a prospective cohort of 162 patients diagnosed of asthma admitted to the First Affiliated Hospital of Xi’an Jiaotong University from January 2018 to December 2019 was used to perform a nested case-control study. Among them, we included 30 patients with chronic persistent asthma between 20 to 35 years old; 30 health control with evenly distributed age and sex were then recruited. Nontargeted metabolomics was applied to identify serum metabolic profiles and altered metabolic pathways. Results: In vitro, human bronchial epithelial cells (HBECs) line BEAS-2B with the addition of L-citrulline and/or asymmetric dimethylarginine (ADMA) model was utilized and the concentrations of nitric oxide (NO) metabolites were tested to evaluate the therapeutic potential of L-citrulline. The young patients with chronic persistent asthma displayed dysregulated serum metabolic profiles, especially enriched in arginine metabolism. The ratio of L-citrulline to ornithine is associated with blood eosinophil count. In vitro, adding L-citrulline could reverse ADMA-mediated reduction of NOx at lower L-arginine concentration (25 μM), but was ineffective in the higher L-arginine concentration (100 μM) media. Conclusions: The arginine metabolism balance is of vital importance during the pathogenesis and progression of chronic asthma. L-citrulline could be a powerful approach to restore airway NO production, potentially exhibiting therapeutic benefits among young patients with chronic asthma.

Clitoria ternatea (Linn.) flower extract attenuates vascular dysfunction and cardiac hypertrophy via modulation of Ang II/AT1 R/TGF-β1 cascade in hypertensive rats.

Clitoria ternatea (CT) (the Fabaceae family) has been reported to elicit several biological responses, such as anti-inflammation and anti-depression effects. This study evaluated the effect of CT flower extract on blood pressure, vascular function, and left ventricular hypertrophy in a two-kidney, one-clip (2K-1C) rat model. Hypertensive rats were treated with CT extract at various doses (100, 300, or 500 mg kg-1 day-1 ) or losartan (10mg kg-1 day-1 ) for 4 weeks (n=8/group). CT extract reduced blood pressure in a dose-dependent manner, and CT extract at a dose of 300 mg kg-1 was an effective concentration (P < 0.05). Augmentation of contractile responses to electrical field stimulation and impairment of vascular responses to acetylcholine in mesenteric vascular beds and aortic rings of 2K-1C rats were suppressed by treatment with CT extract or losartan (P < 0.05). Serum angiotensin-converting enzyme activity and plasma angiotensin II concentration were high in 2K-1C rats but alleviated by CT extract or losartan treatment (P < 0.05). Increases in superoxide production and lipid peroxidation were attenuated in 2K-1C rats treated with CT extract or losartan compared with the untreated group (P < 0.05). Increased plasma concentration of nitric oxide metabolites was found in hypertensive rats that received CT extract or losartan. CT extract or losartan suppressed the overexpression of Ang II receptor subtype I (AT1 -R) and transforming growth factor-β1 (TGF-β1) in 2K-1C rats. CT extract had antihypertensive effects that were associated with improving vascular function and cardiac hypertrophy in 2K-1C rats. The mechanisms involved suppression of the renin-angiotensin system, of oxidative stress, and of the AT1 R/TGF-β1 cascade. © 2021 Society of Chemical Industry.

Ультразвукові та біохімічні показники дисфункції ендотелію при геморагічному васкуліті у дітей

З метою виявлення ультразвукових і біохімічних маркерів дисфункції ендотелію залежно від ступеня активності та форми обстежено 60 дітей з геморагічним васкулітом. Проводили визначення в сироватці крові концентрації МСР-1 імуноферментним методом, вмісту оксиду азоту — за концентрацією його стабільних метаболітів — NO2, NO3 та S-нітрозотіолу, фактора Віллебранда — агрегометричним методом, оцінку товщини комплексу інтима-медіа загальної сонної артерії та визначення ендотелійзалежної дилатації плечової артерії. Рівні фактора Віллебранда та МСР-1 вірогідно підвищуються залежно від ступеня активності геморагічного васкуліту. Статистичні дані вказують на значне зниження концентрації метаболітів оксиду азоту в сироватці крові у дітей зі змішаною формою та нирковим синдромом. Товщина комплексу інтима-медіа загальної сонної артерії збільшувалась у дітей із тяжким перебігом геморагічного васкуліту та у дітей зі змішаною формою з нирковим синдромом. Зафіксована патологічна реакція ендотелійзалежної дилатації плечевої артерії незалежно від ступеня активності та форми геморагічного васкуліту свідчить про безпосереднє залучення в патологічний процес ендотелію.

Antioxidant tempol modulates the increases in tissue nitric oxide metabolites concentrations after oral nitrite administration

Nitric oxide (NO) metabolites have physiological and pharmacological importance and increasing their tissue concentrations may result in beneficial effects. Tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl) has antioxidant properties that may improve NO bioavailability. Moreover, tempol increases oral nitrite-derived gastric formation of S-nitrosothiols (RSNO). We hypothesized that pretreatment with tempol may further increase tissue concentrations of NO-related species after oral nitrite administration and therefore we carried out a time-dependent analysis of how tempol affects the concentrations of NO metabolites in different tissues after oral nitrite administration to rats. NO metabolites (nitrate, nitrite and RSNO) were assessed by ozone-based reductive chemiluminescence assays in plasma, stomach, aorta, heart and liver samples obtained from anesthetized rats at baseline conditions and 15 min, 30 min, 2 h or 24 h after oral nitrite (15 mg/kg) was administered to rats pretreated with tempol (18 mg/kg) or vehicle 15 min prior to nitrite administration. Aortic protein nitrosation was assessed by resin-assited capture (SNO-RAC) method. We found that pretreatment with tempol transiently enhanced nitrite-induced increases in nitrite, RSNO and nitrate concentrations in the stomach and in the plasma (all P < 0.05), particularly for 15–30 min, without affecting aortic protein nitrosation. Pretreatment with tempol enhanced nitrite-induced increases in nitrite (but not RSNO or nitrate) concentrations in the heart (P < 0.05). In contrast, tempol attenuated nitrite-induced increases in nitrite, RSNO or nitrate concentrations in the liver. These findings show that pretreatment with tempol affects oral nitrite-induced changes in tissue concentrations of NO metabolites depending on tissue type and does not increase nitrite-induced vascular nitrosation. These results may indicate that oral nitrite therapy aiming at achieving increased nitrosation of cardiovascular targets requires appropriate doses of nitrite and is not optimized by tempol.

Vasoprotective effects hypotensive therapy in patients with coronary heart disease combined with chronic kidney disease stage 2-3 after coronary stenting

Aim To study the condition of coronary vasculature by data of coronarography (CG) in patients with chronic ischemic heart disease (IHD) and arterial hypertension (AH) associated with stage 2-4 chronic kidney disease (CKD) and to evaluate the effect of a 12-week complex treatment with perindopril or with a combination of perindopril/amlodipine on changes in vascular wall stiffness, endothelial function, and structure and function parameters in this patient category after coronary stenting.Material and methodsr This study included 87 patients with chronic IHD and AH associated with stage 2-3 CKD for whom CG was performed due to ineffectiveness of the antianginal therapy. The patients were divided into three subgroups: subgroup 1 included 28 patients who received a conservative treatment with perindopril 10 mg/day; subgroup 2 consisted of 25 patients who underwent coronary stenting and were prescribed perindopril; subgroup 3 consisted of 34 patients who underwent stenting and were prescribed the perindopril/amlodipine combination. The reference group included 47 patients with IHD and AH with preserved kidney function. Anatomic and functional parameters of the heart, arterial stiffness, pulse wave velocity, cardio-ankle vascular index, augmentation index, central aortic systolic and pulse pressure, endothelium-dependent vasodilation, plasma concentration of endothelin-1 (ET-1), and plasma concentration of nitric oxide metabolites were evaluated at baseline and after 12 weeks of treatment.Results In patients with IHD, AH, and stage 2-3 CKD, arterial stiffness was more pronounced than in patients with preserved kidney function. Concentrations of ET-1 were significantly higher and levels of nitric oxide were lower in CKD. Supplementing the complex therapy with perindopril resulted in a considerable hypotensive effect in all subgroups, improvement of the kidney function, and positive dynamics of arterial stiffness and endothelial function. Changes in these parameters were more pronounced in patients after coronary stenting than in patients receiving only a conservative treatment. The use of perindopril/amlodipine following stenting exerted the most significant angioprotective and cardioprotective effect.Conclusion Patients with IHD and AH in combination with early CKD have pronounced impairment of the condition of arterial blood vessels and the heart. Addition of perindopril to the treatment not only exerted a hypotensive effect but also beneficially influenced mechanisms of progression of this combined pathology.

Intrauterine Nitric Oxide Deficiency Weakens Differentiation of Vascular Smooth Muscle in Newborn Rats.

Nitric oxide (NO) deficiency during pregnancy is a key reason for preeclampsia development. Besides its important vasomotor role, NO is shown to regulate the cell transcriptome. However, the role of NO in transcriptional regulation of developing smooth muscle has never been studied before. We hypothesized that in early ontogeny, NO is important for the regulation of arterial smooth muscle-specific genes expression. Pregnant rats consumed NO-synthase inhibitor L-NAME (500 mg/L in drinking water) from gestational day 10 till delivery, which led to an increase in blood pressure, a key manifestation of preeclampsia. L-NAME reduced blood concentrations of NO metabolites in dams and their newborn pups, as well as relaxations of pup aortic rings to acetylcholine. Using qPCR, we demonstrated reduced abundances of the smooth muscle-specific myosin heavy chain isoform, α-actin, SM22α, and L-type Ca2+-channel mRNAs in the aorta of newborn pups from the L-NAME group compared to control pups. To conclude, the intrauterine NO deficiency weakens gene expression specific for a contractile phenotype of arterial smooth muscle in newborn offspring.

Effects of L-citrulline supplementation on nitric oxide and antioxidant markers after high-intensity interval exercise in young men: a randomized controlled trial.

L-citrulline (L-Cit) is a nonessential amino acid that stimulates nitric oxide (NO) production and improves exercise performance by reducing muscle damage indices; however, the direct benefits of L-Cit on antioxidant markers are unclear. The aim of this study was to examine antioxidant responses to high-intensity interval exercise following acute L-Cit supplementation. Nine young men (21 ± 1 years) participated in a double-blind crossover study in which they received 12 g of L-Cit and placebo (PL) an hour prior to high-intensity interval exercise on two occasions, separated by a seven-day washout period. Blood samples were obtained before (PRE), immediately after (IP), 10 (10P), and 30 min after exercise (30P) from the cubital vein using standard procedures. Serum concentrations of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and NO metabolites (NOx) were measured. The exercise protocol significantly elevated SOD (p = 0.01) and GPx (p = 0.048) from PRE to 10P in the L-Cit group with greater changes than the PL group. CAT concentrations increased IP (p = 0.014) and remained elevated at 10P (p = 0.03) and 30P (p = 0.015) in both the L-Cit and PL conditions. NOx concentrations increased IP (p = 0.05) in the L-Cit group with greater changes than PL group in PRE to IP, PRE to 10P, and PRE to 30P (p < 0.05). Our data indicate that L-Cit supplementation (single 12 g dose pre-exercise) induces improvements in antioxidant markers following a session of high-intensity interval exercise in young men.

Ambulatory Blood Pressure Monitoring and Endothelial Dysfunction in Hypertensive Patients with Diabetes Mellitus Type 2

Aim: Diabetic hypertensive patients have pronounced changes in ambulatory blood pressure profile and endothelial function. But the correlation between the parameters of ambulatory blood pressure monitoring (ABPM) and endothelial dysfunction in diabetic hypertensive patients have not been fully clarified. We studied ABP and endothelial function in a group of diabetic hypertensive patients. Methods: Patients with a glomerular filtration rate (GFR) of less than 30 mL/min per 1.73 m(2) were excluded. 120 patients were included into the research. Of these, the first (basic) group made up diabetic hypertensive patients in which there were 34 males and 26 females, the mean age was 56.1±1.3 years, the duration of arterial hypertension (AH) was 12.3±2.1 years and the duration of type 2 diabetes mellitus (DM2) was 4.4±0,7 years. The second (control) group made up 60 non-diabetic hypertensive patients in which there were 27 males and 33 females, the mean age was 55.2±1.2 year and duration of AH was 11.1±0.9 years. The patients in both groups were similar in age, duration of AH. Results:The analysis of the results of the 24-hour ABPM revealed that the number of patients with increased 24 hour systolic blood pressure (SBP) and diastolic blood pressure (DBP) variability was more among diabetic hypertensive patients than in non-diabetic hypertensive patients (76.7 % versus 21.1 and 70.0 % versus 22.5 %, respectively, p <0,05). There were not any significant changes in pulse rate, SBP and DBP. The amount of non-dipper and night-peaker patients was significantly higher in the basic group than in the control one (60.0 % versus 25.4 %, respectively, p <0,05). It was established that the number of patients with DBP daily value <10 was more significant in diabetic hypertensive patients versus non- diabetic hypertensive patients (33.3 % versus 18.2 %, respectively). We also determined nitric oxide metabolites concentration (nitrites and nitrates (NO)) and endothelin (ET-1) in serum and in 24 h-urine collection to assess endothelial function. So, the concentration of ET-1 in serum was significantly higher in diabetic hypertensive patients compared with non-diabetic hypertensive patients (2.49±0.01 pg/ml versus 1.5±0.07 pg/ml, respectively, p <0,05). NO metabolites concentration in serum and urine was significantly lower in the basic group than in the control group (12.7±1.5 uM versus 19,9±1,8 uM and 428.2±27.9 uM versus 792.1±39.4 uM, respectively, p <0,05). The direct association between SBP, DBP and ET-1 in urine were determined in diabetic hypertensive patients (r = 0.7, r = 0.99, respectively, p < 0.001). The correlation between daily index of SBP and ET-1 in urine (r = -0.58, p < 0.001), daily index of DBP and ET-1 in serum (r = -0.47, p < 0.001) were established in the basic group. Conclusion: The correlation between the parameters of ABPM and endothelial dysfunction in diabetic hypertensive patients were established in this study.

Intrathecal and systemic alterations of L-arginine metabolism in patients after intracerebral hemorrhage

Alterations in the concentration of nitric oxide (NO) and L-arginine metabolites have been associated with the pathophysiology of different vascular diseases. Here, we describe striking changes in L-arginine metabolism after hemorrhagic stroke. Blood and cerebrospinal fluid (CSF) samples of patients with intracerebral hemorrhage (ICH) and/or intraventricular hemorrhage were collected over a ten-day period. Liquid chromatography-tandem mass spectrometry was used to quantify key substrates and products of L-arginine metabolizing enzymes as well as asymmetric (ADMA) and symmetric dimethylarginine (SDMA). Changes in the plasma were limited to early reductions in L-ornithine, L-lysine, and L-citrulline concentrations. Intrathecally, we observed signs of early NO synthase (NOS) upregulation followed by a decrease back to baseline accompanied by a rise in the level of its endogenous NOS-inhibitor ADMA. SDMA demonstrated increased levels throughout the observation period. For arginase, a pattern of persistently elevated activity was measured and arginine:glycine amidinotransferase (AGAT) appeared to be reduced in its activity at later time points. An early reduction in CSF L-arginine concentration was an independent risk factor for poor outcome. Together, these findings further elucidate pathophysiological mechanisms after ICH potentially involved in secondary brain injury and may reveal novel therapeutic targets.