Nitric Oxide Metabolite Levels Research Articles

Markers of the course of obliterating atherosclerosis of lower limb arteries

The purpose of the study was to determine the level of substances damaging the vascular endothelium, as well as to assess their effect on the functional state of the endothelium and the course of obliterating atherosclerosis of lower limb arteries. The study included a total of 112 people, subdivided into three groups: those with an unfavourable course of obliterating atherosclerosis of lower limbs arteries (n=48) - group 1, patients with obliterating atherosclerosis of lower limbs arteries with a conventionally favourable course (n=48) - group 2, and apparently healthy volunteers (n=16). In all subjects, the following parameters were analysed: stable metabolites of nitric oxide II, endothelin-1, homocysteine and basal insulin. The level of stable nitric oxide metabolites (p<0.001 as compared with group 1; p<0.045 compared with group 2) was lower in the groups of patients with obliterating atherosclerosis of lower limb arteries (88.5±7.3 μmol/L in group 1; 161.5±8.6 μmol/L in group 2) as compared with healthy volunteers (226.0±28.6 μmol/L). In its turn, the level of nitric oxide was statistically significantly lower (p<0.001) in group 1 patients as compared with those of group 2. The level of endothelin-1 turned out to be higher (p<0.001) in group 1 (2.1±0.1 ng/ml) as compared with group 2 (1.6±0.1 ng/ml). Comparing group 1 patients with healthy volunteers (1.4±0.1 ng/ml), the level of endothelin-1 had also higher values (p<0.001). The level of endothelin-1 did not differ (p=0.270) as compared with group 2 and healthy volunteers. Comparing the homocysteine level in patients of the examined groups (20.7±0.8 μmol/L in group 1 patients and 18.1±0.6 μmol/L in group 2 patients) with healthy volunteers (13.0±0.4 μmol/L) demonstrated an increase in the parameters (p<0.001). The level of homocysteine turned out to be higher in group 1 patients than in those of group 2 (p<0.001). The level of basal insulin turned out to be significantly higher in the studied groups of patients with obliterating atherosclerosis of lower limb arteries (24.9±4.6 mIU/L in group 1; 8.0±0.7 mIU/L in group 2) than in healthy volunteers (5.1±0.5 mIU/L). Statistically significant (p<0.001) hyperinsulinemia was observed in group 1 as compared with group 2. Hyperhomocysteinemia and hyperinsulinemia are predictors of an unfavourable course of the disease. In a high level of these parameters, one may predict an unfavourable course of obliterating atherosclerosis of lower limb arteries.

Liposome Extract of Stachys pilifera Benth Effectively Improved Liver Damage due to Bile Duct Ligation Rats.

Herbal medicines harbor essential therapeutic agents for the treatment of cholestasis. In this study, we have assessed the anticholestatic potential of Stachys pilifera Benth's (SPB's) hydroalcoholic extract encapsulated into liposomes using bile duct ligation- (BDL-) induced hepatic cholestasis in rats. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), malondialdehyde (MDA), total thiol (T-SH) content, protein carbonyl (PCO), total bilirubin (TBIL), albumin (ALB), and nitric oxide (NO) metabolite levels were measured in either liver tissue or plasma to assess liver damage. Moreover, expression of proinflammatory cytokines (IL-1β and TNF-α) and liver fibrosis markers (TGF-β and SM-α) which are driving forces of many liver disorders was also determined. The activity of AST, ALT, and ALP was significantly enhanced in the BDL group in comparison to the control group; however, treatment with liposomal (SPB) hydroalcoholic extract significantly reduced AST and ALT's activity. Increases in MDA, TBIL, and NO levels and T-SH content due to BDL were restored to control levels by liposomal (SPB) hydroalcoholic extract treatment. Similarly, hepatic and plasma oxidative marker MDA levels, significantly enhanced by BDL, were significantly decreased by liposomal (SPB) hydroalcoholic extract treatment. Moreover, histopathological findings further demonstrated a significant decrease in hepatic damage in the liposomal (SPB) hydroalcoholic extract-treated BDL group. In addition, liposomal (SPB) hydroalcoholic extract treatment decreased the liver expression of inflammatory cytokines (IL-1β, TNF-α) and liver fibrosis markers (TGF-β and SM-α). Since liposomal (SPB) hydroalcoholic extract treatment alleviated the BDL-induced injury of the liver and improved the hepatic structure and function more efficiently in comparison to free SPB hydroalcoholic extract, probable liposomal (SPB) hydroalcoholic extract exhibits required potential therapeutic value in protecting the liver against BDL-caused oxidative injury.

Protective and therapeutic effects of ethanolic extract of Nasturtium officinale (watercress) and vitamin E against bleomycin-induced pulmonary fibrosis in rats.

Background and purpose:Pulmonary fibrosis is a chronic disease of the lungs caused by inflammation, species of reactive oxygen, and immune defects. Antioxidant properties of Nasturtium officinale has been reported in some studies. Therefore, the objective of the current study was to evaluate the effect of ethanolic extract of Nasturtium officinale (EENO) on bleomycin (BLM)-induced lung fibrosis in rats.Experimental approach:Forty adult male Wistar rats (180-220 g) were randomly divided into 5 experimental groups. Normal control, BLM control received a single dose of BLM (6 IU/kg) intratracheally only on the first day, EENO + BLM group received EENO (500 mg/kg) one week before intratracheal BLM instillation and two weeks afterward, BLM + EENO group and BML + vitamin E group received EENO (500 mg/kg) and vitamin E (500 mg/kg) half-hour after BLM installation, respectively. The animals were sacrificed on day 22. Change in body weight, lung index, serum level of malondialdehyde (MDA) and nitric oxide (NO) metabolite, lung tissue hydroxyproline content and lung pathology were assessed.Findings/Results:Pre- or post-treatment with EENO attenuated pulmonary fibrosis as evidenced by normalized lung index, improved histological changes and inhibited collagen deposition (hydroxyproline) in the animal lung. EENO also decreased MDA and NO metabolite release in comparison to the BLM control. vitamin E (500 mg/ kg) also significantly inhibited the BLM-induced lung toxicity.Conclusions and implications:EENO can prevent BLM-induced lung fibrosis in rats via antioxidant activities. However, more studies are needed to elicit the exact mechanism of this effect.

Effects of moderate exercise on lipopolysaccharide-induced inflammatory responses in rat's cardiac tissue

The effects of moderate exercise on cardiac tissue inflammation, oxidative stress markers and apoptosis in lipopolysaccharide (LPS)-administered rats were evaluated.Wistar rats were divided into three groups (N = 8): (1) control; (2) LPS (1 mg/kg); and (3) LPS + moderate training (LPS + EX: 15 m/min, 30 min/day, for 9 weeks (week 1–9)). LPS was injected intraperitoneally for 5 days during week 9. Finally, the rats' heart were removed for biochemical and expression assessments.LPS increased the levels of tumor necrosis factor α (TNF-α), interleukin (IL)- 1β, C-reactive protein (CRP), malondialdehyde (MDA) and nitric oxide (NO) metabolites in cardiac tissue, but decreased thiol contents and catalase (CAT) and superoxide dismutase (SOD) activity in cardiac tissue compared to the control group (p < 0.05–p < 0.001). In LPS + EX group, the level of NO metabolites was increased (p < 0.05) and thiol contents were decreased (p < 0.001) compared to the control group. Moderate training decreased the levels of TNF-α, IL-1β, CRP and NO metabolites while increased CAT activity in the LPS + EX group compared to the LPS group (p < 0.05–p < 0.001). The mRNA level of BAX in the LPS group and the BCL2/BAX ratio in both LPS and LPS + EX groups increased compared to the control group (p < 0.05–p < 0.01).These results indicated that moderate training improved LPS-induced deleterious effects on cardiac tissue by attenuating proinflammatory cytokine levels, apoptosis and oxidative damage.

Nitric Oxide Production in Professional Skiers During Physical Activity at Maximum Load.

The purpose of this study is to assess the production of nitric oxide in professional cross-country skiers with normotensive and hypertensive responses to physical activity at maximum load. The observation group included professional cross-country skiers (22.2 ± 7.1 years, = 107) who were current members of the national team of the Komi Republic. All the examined athletes performed the exercise test on a cycle ergometer “until exhaustion.” The following parameters were determined for each participant while they were sitting at rest, while at their anaerobic threshold level, during peak load, and during the recovery period (5th min): systolic blood pressure, diastolic blood pressure, heart rate, and the level of stable nitric oxide metabolites (nitrites, nitrates) in capillary blood samples. According to the blood pressure results, the cross-country skiers were divided into two groups. Group I included athletes with a normotensive response to stress. Group II was composed of individuals with a hypertensive response to stress. During the performance of the test “until exhaustion,” a significant (p < 0.05) increase in the amount of stable metabolites of nitric oxide was observed in the group of athletes with a normotensive response to the load compared with the group with a hypertensive response to the load. In athletes with a normotensive reaction to the load during exercise at maximum load and in the early recovery period, nitrate was prioritized in the regulation of vascular tone. The exercise test on a cycle ergometer “until exhaustion,” combined with the assessment of the levels of stable nitric oxide metabolites in plasma, can be considered a test for the early diagnosis of endothelial dysfunction in professional athletes.

The T786C polymorphism of NOS3 gene effect on the level of nitric oxide metabolites among patients with non-valvular paroxysmal atrial fibrillation

The objective of the research - to determine the the T786C polymorphism of nos3 gene effect on the level of nitric oxide metabolites among patients with non-valvular paroxysmal atrial fibrillation.Material and methods. To achieve this goal, a prospective study was conducted on the basis of the communal uncommercial company “City Hospital № 10” of Zaporizhzhia City Council. The sample of patients was conducted in the period from 2014 to 2019. The results of the study are based on data from a comprehensive examination and dynamic monitoring of 176 patients with paroxysmal atrial fibrillation on the background of coronary heart disease combined with hypertension, of which 98 were from the city of Zaporizhzhia and 78 were from rural areas. Almost healthy 31 volunteers were examined on an outpatient basis.Results. Plasma NO2 levels in both groups area urban and rural patients - 7.02 [5.74 ; 8.14] mmol/L and 6.77 [5.47 ; 7.98] mmol/l, respectively, were significantly lower compared to 8.46 [7.45 ; 9.45] mmol/L in the healthy group (p&lt;0.05). Significantly, the lowest level of NO3 was in the group of patients from the city of 10.36 [8.14 ; 13.32] mmol/L, in vs. to the value of 11.69 [10.36; 15.33] mmol/L in the group of patients from rural areas and against 13.36 [11.85 ; 15.35] mmol/L in the group of healthy individuals, (p&lt;0.05). The highest value of NO2+NO3 was in the group of healthy people - 21.56 [20.38 ; 24.53] mmol/L, against the level of 18.02 [15.83 ; 21.78] mmol/L in the group of patients from rural areas and - 17.60 [14.80 ; 20.35] mmol/L in the group from urban area (p &lt; 0.05). The median NO2 level in the subgroup of homozygotes for the T allele was 7.86 [6.66; 8.88] mmol/L and was significantly higher than in the subgroup of heterozygotes TC - 6.66 [5.18; 7.98] mmol/L – and the subgroup of homozygotes for the C - 5.81 [5.07; 6.72] mmol/l (p&lt;0.05). The highest value of NO2+NO3 was in the homozygote subgroup for the T - 20.35 [17.07 ; 25.16] mmol/l, both against the level of 17.52 [15.37 ; 20.72] mmol/L of the TC heterozygote subgroup, and against 16.41 [14.48; 17.93] mmol/L of the homozygote subgroup for the C allele (p&lt;0.05). However, there was no significant difference between the heterozygote and homozygote subgroups for the C allele (p&gt;0.05). Conclusions. Decreased nitric oxide metabolites occur among patients with non-valvular paroxysmal atrial fibrillation compared with the healthy group. The level of nitrate-ions in the group of patients from the city was significantly lower than in the group of patients from the rural areas. The level of nitrite-ions was lower among patients with the C allele of the T786C polymorphism of the 3 type of nitric oxide synthase gene, whereas the value of nitrate-ions did not depend on this polymorphism.

The Oral Mucosa Status and the Correlation between the Functional Parameters and the Level of Nitric Oxide Metabolites in Saliva among Patients with GERD.

The study involved 91 patients (48 women and 43 men), aged from 18 to 70 years with GERD. All patients underwent the clinical dental examination according to a single scheme including general clinical manifestations (nausea, single vomiting, belching, heartburn, pain in the epigastrium and around the navel, and poor appetite) and dental manifestations of GERD. The objective assessment of the dental status of the examined patients included the measurement of the functional parameters of the mixed saliva, buffer capacity (BC) of saliva, and the detection of the nitric oxide metabolites (NOx) content in saliva from the right parotid salivary gland (“SRPSG”) and in blood serum using the indirect method based on the determination of the stable metabolites: nitrates and nitrites using the Griess reaction. It was established that salivation rate among patients with GERD with the prevailing of ACR and SACR was at the lower limit of normal values (0.32 + 0.19 ml/min), and the salivation rate among patients with the prevailing of SALCR was low (0.10 + 0.04 ml/min). The BC of saliva among patients with the prevailing of ACR and SACR was high (9.07 + 1.23 mmol eq/l and 9.40 + 1.71 mmol eq/l, respectively) and was reduced among patients with the prevailing of SALCR (7.63 + 0.18 mmol eq/l). The NOx level in SRPSG among patients with GERD was increased (especially in Group 3 (20.93 + 11.23 umol/l)). The direct correlation between the indicators of sialometry, the level of the BC of saliva, and the NOx level in SRPSG were established during the study.

Relationship between Pro- and Antioxidant Status and Cytokine Profile in Piglets under Technological Stress

The study outcomes of dynamic parameters for the pro- and anitoxidant status and the cytokine profile in piglets under the stress caused by weaning them from sows for their transfer to growing-fattening facilities under conditions of an industrial-sized pig farm are reported. It has been ascertained that the technological stress affecting the animals is followed by increasing the contents of malondialdehyde and medium molecular-weight peptides, the endogenous intoxication, and the level of proinflammatory cytokines on days 3–10 after the stress effect. Increasing the antioxidant-defense enzyme activity and the levels of stable nitric-oxide metabolites and IL-4 and IL-10 anti-inflammatory cytokines contributed to normalizing the body’s metabolic processes and decreasing the contents of IL-1β, TNF-α, and IFN-γ anti-inflammatory cytokines. The dynamics of variations in the pro- and anitoxidant status and the cytokine profile can indicate their interdependence under the oxidative stress associated with the events of weaning and transferring them to growing-fattening facilities. The process of adaptation to the new conditions was usually completed on the 20th day after the stress effect. In addition, most analyzed parameters were restored to the preweaning levels.

Pathogenetic Value of pVM82 Plasmid of Yersinia Pseudotuberculosis, Causative Agent of Far Eastern Scarlet-Like Fever

The Far Eastern scarlet-like fever (FESLF) is the clinical-epidemic manifestation of pseudotuberculosis infection in humans is associated with a specific clonal lineage of the causative agent. Purpose of the study: to determine the pathogenetic value of the pVM82 plasmid of the FESLF causative agent, on the basis of a comparative analysis of the innate immunity cells metabolic activity and peculiarities of the inflammatory reaction during experimental infection, caused by different plasmid types of Yersinia pseudotuberculosis. Materials and Methods. The following Y. pseudotuberculosis plasmid types were used for the infection of mice: (1) H-5015 T+ strain (82+:48+) containing two plasmids pVM82 and pYV; (2) H-5015 T– strain (82+:48–) containing single pVM82 plasmid; (3) H-5013 T+ strain (48+) containing single pYV plasmid; (4) H-5013 T– plasmid-free strain (82–:48–). Peritoneal exudate cells and samples of liver, spleen and mesenteric lymph nodes were taken from infected animals at 1, 3, 5 and 7 days post infection. The functional state of the innate immunity cells was assessed by the activity of lactate dehydrogenase (LDH) and by the level of nitric oxide (NO) metabolites. The samples of target organs were embedded in paraffin, sections were stained with hematoxylin and eosin. Results. It was found that only Y. pseudotuberculosis strains containing pVM82 plasmid had a stimulating effect the innate immunity cells. The more pronounced increase in the LDH activity, an oxygen-dependent metabolism enzyme, and the level of NO metabolites occurred in response to infection of cells with bacteria containing single pVM82 plasmid, compared with plasmid type containing additional plasmid virulence pYV. In experimental animals infected with plasmid type pYV–: pVM82+ of Y. pseudotuberculosis, the disease pathology usually manifested less acute inflammation with a predominance of mononuclear cells and minor pathogen-associated destructive changes in organs. The mortality in animals infected with Y. pseudotuberculosis strains containing plasmid pVM82 (plasmid types 82+:48+ and 82+:48–) was lower compared to a strain carrying only the virulence plasmid pYV (plasmid type 48+),—40, 30 and 80%, respectively. Conclusions. Thus, the pVM82 plasmid of Y. pseudotuberculosis determined the effective immune defense of organism, mainly through nitroxide-dependent bactericidal mechanisms of innate immunity cells. Moreover, the restriction of a generalized inflammatory reaction and induction of granulomatous inflammation were associated with this plasmid.

Effects of Dietary Brown Rice on Carcass Composition and Nitric Oxide (NOx) Metabolite Levels in High-Fat High-Fructose Diet-induced Sprague Dawley Rats as Obesity Model

Obesity is characterized by excessive accumulation of fat in the body, which causes changes in body composition and endothelial dysfunction due to impaired production of nitric oxide (NO). The common means of managing obesity is through functional food, such as brown rice, which has high fiber and antioxidant content. Therefore, the purpose of this study was to determine the effect of adding brown rice to feed on carcass composition and NOx levels in obese rats. This was an experimental study involving male Sprague Dawley rats placed in 5 groups, in which 4 were allowed to turn to obese rats with the remaining one group as control. These 4 groups were allowed to later feed on high-fat high-fructose (HFHF) diet while the control fed on the normal AIN-93 diet, followed by 8 weeks of HFHF intervention and brown rice in feed with 3 different doses; 12.43%; 24.86%; and 37.29%. The serum NOx levels were analyzed by the Griess Reaction method, while the percentage of protein and fat was analyzed through Gravimetric Extraction. The results showed that the addition of brown rice resulted in changes in the Lee index (p = 0.000) and abdominal circumference (p = 0.000). Also, a correlation was observed between the Lee index and abdominal circumference (p = 0.001; r = 0.558) of rats. However, there was no significant difference between NOx and carcass protein levels, and there was an increase in carcass fat levels due to an increase in mitochondrial energy efficiency and resistance to protein synthesis in obese rats.

Syzygium gratum Extract Alleviates Vascular Alterations in Hypertensive Rats.

Background and Objectives: Syzygium gratum (SG) is a local vegetable and widely consumed in Thailand. Previously, a strong antioxidative effect of SG extract has been reported. The effects of SG extract on hypertension have remained unknown. The effect of SG aqueous extract on blood pressure and vascular changes were examined in L-NAME-induced hypertensive rats (LHR), and its potential active constituents were also explored. Materials and Methods: Male Sprague Dawley rats were allocated to control, L-NAME (40 mg/kg/day), L-NAME + SG (100, 300, 500 mg/kg/day), or captopril (5 mg/kg/day) groups. The components of SG extract were analyzed. Results: The analysis of aqueous SG extract was carried out using HPLC-Mass spectroscopy, and phenolic compounds could be identified as predominant components which might be responsible for its antihypertensive effects observed in the LHR model (p < 0.05). Additionally, SG extract also improved vascular responses to acetylcholine and decreased vascular remodeling in LHR (p < 0.05). Enhancements of eNOS expression and plasma nitric oxide metabolite levels, and attenuation of angiotensin converting enzyme (ACE) activity and plasma angiotensin II levels were observed in the LHR group treated with SG. Moreover, SG exhibited strong antioxidant activities by reducing vascular superoxide generation and systemic malondialdehyde in LHRs. Captopril suppressed high blood pressure and alleviated vascular changes and ACE activity in LHRs, similar to those of the SG extract (p < 0.05). Conclusion: Our results suggest that the SG extract exhibited antihypertensive effects, which is relevant to alleviation of vascular dysfunction and vascular remodeling of LHRs. These effects might be mediated by phenolic compounds to inhibit ACE activity and scavenge reactive oxygen species in LHR.

The effects of malvidin on oxidative stress parameters and inflammatory cytokines in LPS-induced human THP-1 cells.

Malvidin is an anthocyanin which is involved in inhibiting inflammatory-related mediators in inflammatory diseases; however, its mechanism of action in THP-1 cells is not yet known. THP-1 is a human monocytic cell line that is derived from patients with acute monocytic leukemia. The present study aimed to investigate the effect of malvidin on inflammatory responses and oxidative stress in lipopolysaccharide (LPS)-induced THP-1 cells. THP-1 cells were stimulated with LPS (50 ng/ml) to induce inflammation in the presence or absence of malvidin. The anti/proinflammatory cytokines were evaluated by real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Total protein levels/phosphorylation of c-Jun N-terminal kinase (JNK), P65-NF-κB, and IKKα/IKKβ were evaluated by western blotanalysis. Malondialdehyde (MDA) and nitric oxide (NO) metabolite levels, ferric reducing antioxidant power (FRAP), total thiol (T-SH) content, and superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity were measured to evaluate the antioxidant activity of malvidin in THP-1 cells. Treatment of LPS-stimulated THP-1 cells with malvidin (100 and 200 μM) led to the significant inhibition of interleukin-6 (IL-6), tumor necrosis factor-α, and IL-1β messenger RNA (mRNA) expression and protein levels as well as a significant increase in the IL-10 mRNA expression and protein secretion. Moreover, 200 μM malvidin treatment reduced the phosphorylation of JNK, IKKα/IKKβ, and P65-NF-κB. These findings showed that malvidin not only decreased the MDA and NO metabolite levels but also increased the FRAP and T-SH content as well as SOD and GPx activities. The findings of the present study demonstrated the potential role of malvidin in blocking inflammation and oxidative stress induced by LPS in THP-1 cell line, suggesting that malvidin is likely to be a therapeutic agent for inflammatory diseases.

Neuroprotective Effect of Intravitreal Single-Dose Lithium Chloride after Optic Nerve Injury in Rats

ABSTRACT Objective Lithium is an old drug to control bipolar disorder. Moreover, it presents neuroprotective effects and supports neuronal plasticity. The aim of this study was to evaluate neuroprotective effect of intravitreal lithium after optic nerve injury. Methods Three dosages of lithium chloride, including 2 pmol, 200 pmol, and 2 nmol, were injected intravitreally after rat optic nerve injury. Proteins expression were assessed by western blot. Nitric oxide (NO) metabolites were measured by Griess test. Visual evoked potential (VEP) and optical coherence tomography (OCT) measurement were performed after trauma induction, in addition to H & E and TUJ1 staining of ganglion cells. Results Western blot depicted lithium can significantly increase antiapoptotic Bcl-2 protein level and reduce p-ERK, Toll-like receptor 4 (TLR4) and proapoptotic proteins such as Bax level in retinal tissue and Griess test reflected that NO metabolites level decreased in lithium treated eyes (P < .05). While, OCT showed no significant changes (P = .36 and P = .43 comparing treated group with trauma) in retinal ganglion cell layer thickness after lithium injection, VEP P2 wave amplitude increased significantly (P < .01) in lithium-treated eyes and its latency reduced (P < .05 for N1 wave and P < .01 for P2 wave). Tuj1 antibody-labeled retinal ganglion cells analyzing showed that the number of retinal ganglion cells were significantly higher in lithium treated eyes compared to untreated eyes with optic nerve injury. Conclusion It seems intravitreally lithium has optic nerve neuroprotective effects by various mechanisms like overexpression of antiapoptotic proteins, suppressing proinflammatory molecules and proapoptotic factors, and decreasing nitric oxide.

Transplanted Kidney Increases Nitric Oxide Formation With Metabolic Acidosis Reduction.

As a vasodilator, nitric oxide is considered to play a significant role in the homeostatic regulation of renal hemodynamics. To test the hypothesis that a kidney graft is capable of producing nitric oxide immediately after renal transplant surgery, we examined the possibility that it positively affects local metabolic acidosis. In kidney transplant recipients, we analyzed renal vein and central vein blood samples, which reflect local and systemic metabolic alterations, respectively. Samples were taken immediately after kidney recirculation (that is, the first blood passing through after clamps are released) and at 5, 15, and 30 minutes thereafter. Levels of nitric oxide metabolites (nitrites, nitrates, and their sum), malondialdehyde (an indicator of oxidative damages), and parameters of acid-base balance (pH level, actual excess base, hemoglobin, actual bicarbonate, partial pressure of carbon dioxide, partial pressure of oxygen) were analyzed. Living kidney donors (the recipients' parents) were controls. In renal vein samples, nitrates and the sum of nitrites and nitrates were significantly higher than that shown in control (P < .001) and central vein (P < .05) samples, suggesting an immediate increase in nitric oxide production in the transplanted organ. Metabolic acidosis occurred in both the renal and central vein, indicated by decreased pH and actual bicarbonate level as well as by negative actual base excess level. Only in the renal vein was an increased nitrite and nitrate associated with a reduction of negative actual excess base, thereby suggesting a decrease in anion formation. Transplanted kidneys increase nitric oxide production immediately after organ transplant surgery, which positively affects local metabolic acidosis. The mechanism for this effect is likely local circulation improvement.

Estrogen receptor (ESR1 and ESR2)-mediated activation of eNOS–NO–cGMP pathway facilitates high altitude acclimatization

Higher levels of circulatory nitric oxide (NO) and NO metabolites reportedly facilitate high altitude acclimatization. But the underlying factors and molecular pathways promoting NO production at high altitude has been poorly characterized. Studying healthy lowlanders at sea level (C, lowlander) and high altitude (3500 m, after day 1, 4 and 7 of ascent), we report higher protein levels of eNOS and eNOSSer1177, higher plasma levels of BH4, NOx (nitrate and nitrites), cGMP and lower levels of endogenous eNOS inhibitor ADMA during healthy high altitude acclimatization. Our qRT-PCR-based gene expression studies identified higher levels of eNOS/NOS3 mRNA along with several other eNOS pathway genes like CALM1, SLC7A1 and DNM2. In addition, we observed higher mRNA levels of estrogen (E2) receptors ERα/ESR1 and ERβ/ESR2 at high altitude that transcriptionally activates NOS3. We also observed higher mRNA level of membrane receptor ERBB2 that phosphorylates eNOS at Ser1177 and thus augments NO availability. Evaluating E2 biosynthesis at high altitude, we report higher plasma levels of CYP11A1, CYP19A1, E2, lower levels of testosterone (T) and T/E2 ratio as compared to sea level. Correlation studies revealed moderate positive correlation between E2 and NOx (R = 0.68, p = 0.02) after day 4 and cGMP (R = 0.69, p = 0.02) after day 7 at high altitude. These findings suggest a causative role of E2 and its receptors ESR1 and ESR2 in augmenting eNOS activity and NO availability during healthy high altitude ascent. These results will aid in better understanding of NO production during hypobaric hypoxia and help in designing better high altitude acclimatization protocols.

The Nitric Oxide Metabolite Level and NOS2 and NOS3 Gene Transcripts in Patients with Essential Arterial Hypertension

It was shown that the level of nitric oxide metabolites in the blood plasma of people with essential arterial hypertension (EAH) is significantly higher than that of healthy donors. This pattern did not depend on the stage of the disease, but on the age of the subjects, as well as on whether patients with cardio-selective β-adrenoreceptor blockers take them or not. It was established that an increase in the level of nitrites and nitrates in the blood of patients with EAH was accompanied by an increase in the level of transcripts of the NOS2 gene in the peripheral blood leukocytes (PBL), while the mRNA content of the NOS3 gene in the PBL patients was slightly lower than that of healthy donors.

The Cardioprotective Effects of Aminoguanidine on Lipopolysaccharide Induced Inflammation in Rats.

Myocardial dysfunction, a major component of sepsis-induced multiorgan failure, contributes to the production of massive amounts of pro-inflammatory cytokines. Nitric oxide (NO) is known to act as a precursor of free radicals in inflammation. This research was conducted to assess the effect of aminoguanidine (AG) on lipopolysaccharide (LPS)-induced heart injury. 50 male rats were categorized into five groups (n = 10): (1) control, (2) LPS, (3) LPS-AG50, (4) LPS-AG100, and (5) LPS-AG150. LPS (1mg/kg) was injected for 5weeks, and AG (50, 100 and 150mg/kg) was injected 30min prior to LPS administration. All drugs were injected intraperitoneally. LPS-evolved cardiovascular toxicity was indicated by the augmentation in the level of nitric oxide (NO) metabolites, interleukin (IL)-6 and malondialdehyde (MDA), as well as reduced contents of total thiol groups, catalase (CAT), and superoxide dismutase (SOD) activity in serum, heart, and aortic tissues. In AG treated groups, noxious effects of LPS were not observed in the serum and harvested tissues. AG reduced MDA, NO metabolites, and IL- 6 and increased total thiol, CAT, and SOD activity in the heart, aorta and serum. As an inhibitor of inducible NO synthase (iNOS), AG further reduced LPS-induced oxidative stress and inflammation, hence considered as cardioprotective.

Norvaline Reduces Blood Pressure and Induces Diuresis in Rats with Inherited Stress-Induced Arterial Hypertension.

Growing evidence suggests that increased arginase activity affects vital bioprocesses in various systems and universally mediates the pathogenesis of numerous metabolic diseases. The adverse effects of arginase are associated with a severe decline in L-arginine bioavailability, which leads to nitric oxide synthase substrate insufficiency, uncoupling, and, eventually, superoxide anion generation and substantial reduction of nitric oxide (NO) synthesis. In cooperation, it contributes to chronic oxidative stress and endothelial dysfunction, which might lead to hypertension and atherosclerosis. Recent preclinical investigations point arginase as a promising therapeutic target in ameliorating metabolic and vascular dysfunctions. In the present study, adult rats with inherited stress-induced arterial hypertension (ISIAH) were used as a model of hypertension. Wistar rats served as normotensive controls. Experimental animals were intraperitoneally administered for seven days with nonproteinogenic amino acid L-norvaline (30 mg/kg/day), which is a potent arginase inhibitor, or with the vehicle. Blood pressure (BP), body weight, and diuresis were monitored. The changes in blood and urine levels of creatinine, urea, and NO metabolites were analyzed. We observed a significant decline in BP and induced diuresis in ISIAH rats following the treatment. The same procedure did not affect the BP of control animals. Remarkably, the treatment had no influence upon glomerular filtration rate in two experimental groups, just like the daily excretion of creatinine and urea. Conversely, NO metabolite levels were amplified in normotonic but not in hypertensive rats following the treatment. The data indicate that L-norvaline is a potential antihypertensive agent and deserves to be clinically investigated. Moreover, we suggest that changes in blood and urine are causally related to the effect of L-norvaline upon BP regulation.

Evaluation of human macrophage functional state by voltammetric monitoring of nitrite ions.

The method for assessing the level of nitric oxide (II) (NO) by voltammetric monitoring of nitrite ions was carried out on models M1 and M2 of polarized macrophages induced from monocytes of human peripheral blood with the addition of lipopolysaccharide (LPS) and interleukin-4 (IL-4), respectively. The model of induction of M1 and M2 macrophages was used in the work to achieve the corresponding shifts in the functional status of studied cells. Ethyl nitrite (EtONO) was used as a standard compound of nitrite ions for electrochemical measurements. Electrochemical determination of nitrite ions was performed by anodic linear sweep voltammetry in the first-order derivative mode (ALSV FOD) in Britton-Robinson (BR) buffer with pH4.02 on carbon ink modified graphite electrode. EtONO calibrations were linear over a concentration range from 2 to 9μmolL-1 with corresponding regression equation y = 0.768c - 0.048. Limit of detection (LOD) (S/N = 3) was 0.38μmolL-1. The results of the study showed the fundamental possibility of using voltammetry to assess indirectly the production of nitric oxide by cells in supernatants of the monocytic macrophage lineage. The level of nitric oxide metabolites (nitrite ions) in supernatants was associated with the functional state of macrophages.

The Effect of Type of Delivery on the Nitric Oxide Metabolites and Endothelial Dysfunction in Pregnant Women.

Background:Since endothelial dysfunction is related to atherosclerosis, this study was planned to determine the effect of type of delivery on Nitric Oxide (NO) metabolites and endothelial function.Materials and Methods:This Cohort study was conducted in 2015 in selected hospitals of Isfahan. 88 nulliparous women with gestational age of 39 weeks and above were enrolled in this study using convenience sampling method and finally, after giving birth, 51 mothers with vaginal delivery, 21 with urgent C-section and 13 with elective C-section were considered for data analysis. The serum levels of NO metabolites were measured in the laboratory with standard kits and data was analyzed using student and paired t-test, one-way ANOVA, and Chi-square test. The significance level was considered less than 0.05 for all tests.Results:The NO metabolites levels in mothers who had vaginal delivery or urgent C-section showed a significant difference before and after delivery (normal vaginal delivery (NVD): t50 = 5.61, p < 0.001, Urgent C-section: t23 = 5.38, p < 0.001). But those with elective C-section showed no significant difference in the nitrate and total nitrite levels before and after delivery (p > 0.05).Conclusions:Since reduction in serum levels of NO metabolites may possibly indicate endothelial dysfunction and predict cardiovascular disease, especially atherosclerosis in the future, it could be concluded that, childbirth, regardless of the type of delivery, could damage the endothelial cells but C-section (urgent or elective) could cause more disruption than vaginal delivery.