Stable Nitric Oxide 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.

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.

Endothelium-Mimicking Multifunctional Coating Modified Cardiovascular Stents via a Stepwise Metal-Catechol-(Amine) Surface Engineering Strategy.

Stenting is currently the major therapeutic treatment for cardiovascular diseases. However, the nonbiogenic metal stents are inclined to trigger a cascade of cellular and molecular events including inflammatory response, thrombogenic reactions, smooth muscle cell hyperproliferation accompanied by the delayed arterial healing, and poor reendothelialization, thus leading to restenosis along with late stent thrombosis. To address prevalence critical problems, we present an endothelium-mimicking coating capable of rapid regeneration of a competently functioning new endothelial layer on stents through a stepwise metal (copper)-catechol-(amine) (MCA) surface chemistry strategy, leading to combinatorial endothelium-like functions with glutathione peroxidase-like catalytic activity and surface heparinization. Apart from the stable nitric oxide (NO) generating rate at the physiological level (2.2 × 10−10 mol/cm2/min lasting for 60 days), this proposed strategy could also generate abundant amine groups for allowing a high heparin conjugation efficacy up to ∼1 μg/cm2, which is considerably higher than most of the conventional heparinized surfaces. The resultant coating could create an ideal microenvironment for bringing in enhanced anti-thrombogenicity, anti-inflammation, anti-proliferation of smooth muscle cells, re-endothelialization by regulating relevant gene expressions, hence preventing restenosis in vivo. We envision that the stepwise MCA coating strategy would facilitate the surface endothelium-mimicking engineering of vascular stents and be therefore helpful in the clinic to reduce complications associated with stenosis.

Studies to Elucidate the Effects of Furostanol Glycosides from Dioscorea deltoidea Cell Culture in a Rat Model of Endothelial Dysfunction.

Currently, there is no doubt surrounding a theory that the cardiotropic effects of sex hormones can be due to their direct effect on the cardiovascular system. In recent years, interest in the study of steroid glycosides has increased. We studied the effects of furostanol glycosides (protodioscin and deltozid) from the cell culture of the Dioscorea deltoidea (laboratory code DM-05) on the physiological and biochemical parameters of vascular endothelial function in hypoestrogen-induced endothelial dysfunction after bilateral ovariectomy. It was shown that the use of DM-05 at a dose of 1 mg/kg makes it possible to prevent the development of arterial hypertension (the level of systolic blood pressure (SBP) decreases by 9.7% (p < 0.05) and diastolic blood pressure (DBP) by 8.2%), to achieve a decrease in the coefficient of endothelial dysfunction by 1.75 times against the background of a hypoestrogenic state. With DM-05, an increase in the concentration of stable nitric oxide metabolites (NOx) by 45.6% (p < 0.05) and an increase in mRNA endothelial nitric oxide synthase (eNOS) expression by 34.8% (p < 0.05) was established, which indicates a positive effect of furostanol glycosides on the metabolism of nitric oxide after ovariectomy. Positive dynamics in the histological structure of the heart and the abdominal aorta indicate the pronounced endothelio- and atheroprotective effects of DM-05.

The study of the endothelial protective properties of the L-norvaline combination with mexidol in the simulation of L-NAME-induced NO deficiency

Introduction: The endothelium is considered as a target for the prevention and treatment of pathological processes leading to cardiovascular diseases.&#x0D; Materials and methods: Endothelial dysfunction was simulated in male rats using an e-NOS inhibitor L-NAME (25 mg/kg/day intraperitoneally, 7 days). This pathology was then corrected by administering mexidol at a dose of 60 mg/kg and L-norvaline at a dose of 10 mg/kg, as well as the combination of both at the same doses, intragastrically, through an atraumatic probe, once a day.&#x0D; Results and discussion: A combination of L-norvaline at a dose of 10 mg/kg and mexidol at a dose of 60 mg/kg against the background of L-NAME-induced endothelial dysfunction has a pronounced endothelial protective effect. This is reflected in the prevalence of endothelial-dependent vascular relaxation, a significant decrease in the coefficient of endothelial dysfunction, as well as the prevention of a decline in the concentrations of stable nitric oxide metabolites and of a decrease in the level of the inflammatory changes marker in the vascular wall. The combination of L-norvaline and mexidol, with different pathogenetic action mechanisms, has a pronounced endothelial protective effect because of their antioxidant properties (mexidol) and donation of nitric oxide (L-arginine).&#x0D; Conclusion: The investigated drugs showed pronounced endothelial protective activity and can be recommended for further pre-clinical studies.

Nitric oxide-releasing nanoparticles improve doxorubicin anticancer activity.

PurposeAnticancer drug delivery systems are often limited by hurdles, such as off-target distribution, slow cellular internalization, limited lysosomal escape, and drug resistance. To overcome these limitations, we have developed a stable nitric oxide (NO)-releasing nanoparticle (polystyrene-maleic acid [SMA]-tert-dodecane S-nitrosothiol [tDodSNO]) with the aim of enhancing the anticancer properties of doxorubicin (Dox) and a Dox-loaded nanoparticle (SMA-Dox) carrier.Materials and methodsEffects of SMA-tDodSNO and/or in combination with Dox or SMA-Dox on cell viability, apoptosis, mitochondrial membrane potential, lysosomal membrane permeability, tumor tissue, and tumor growth were studied using in vitro and in vivo model of triple-negative breast cancer (TNBC). In addition, the concentrations of SMA-Dox and Dox in combination with SMA-tDodSNO were measured in cells and tumor tissues.ResultsCombination of SMA-tDodSNO and Dox synergistically decreased cell viability and induced apoptosis in 4T1 (TNBC cells). Incubation of 4T1 cells with SMA-tDodSNO (40 µM) significantly enhanced the cellular uptake of SMA-Dox and increased Dox concentration in the cells resulting in a twofold increase (P<0.001). Lysosomal membrane integrity, evaluated by acridine orange (AO) staining, was impaired by 40 µM SMA-tDodSNO (P<0.05 vs control) and when combined with SMA-Dox, this effect was significantly potentiated (P<0.001 vs SMA-Dox). Subcutaneous administration of SMA-tDodSNO (1 mg/kg) to xenografted mice bearing 4T1 cells showed that SMA-tDodSNO alone caused a twofold decrease in the tumor size compared to the control group. SMA-tDodSNO in combination with SMA-Dox resulted in a statistically significant 4.7-fold reduction in the tumor volume (P<0.001 vs control), without causing significant toxicity as monitored through body weight loss.ConclusionTaken together, these results suggest that SMA-tDodSNO can be used as a successful strategy to increase the efficacy of Dox and SMA-Dox in a model of TNBC.

The pathogenetic role of the nitric oxide system and its metabolites in the development and progression of chronic heart failure

Aim: to study the activity of eNOS, the concentration of L‑arginine and stable nitric oxide metabolites, as well as the degree of endothelium dependent vasodilation with 5‑minute compression test of the brachial artery in patients with chronic heart failure (CHF) of ischemic origin depending on L‑arginine administration in the treatment scheme.Material and methods. In the present study were included 303 patients (204 men and 99 women) observed about CHF ischemic genesis. Patients of the main group A+ (101 persons), in addition to the main treatment, took L‑arginine at a dose of 1 g 3 times per day in syrup (Tivortin), the rest of the patients (202 persons) were included in the comparison group А - . As a control group were examined 20 healthy volunteers. The metabolism of NO and endothelium-dependent vasodilatation were studied by determining the activity of eNOS, and concentration of NO2/NO3, determining the level of L‑arginine in the blood, assessment of endothelial function with a compression test. The endothelial function of vessels was judged according to the dopplerography of the brachial artery using the method of Solomon et al.Results. In patients taking arginine were observed additional positive effect on the arginine concentration in the peripheral blood (51,63% against 43,53% in group A, p<0.01). The distribution of the patients according to the status of LV systolic function showed that the effect of additional application of arginine is observed only in patients with low LVEF (69,63% vs 58,32% in the group with low LVEF, p<0.01). Also it was discovered that the use of arginine promotes a significantly greater increase in eNOS activity (11,53% against 4.76 per cent, p<0.001. In comparison with patients within the groups A+ and A —, classified according to the state of LV systolic function, it was found a significantly more pronounced effect of arginine in patients with normal systolic LV function.Conclusions. Patients with chronic heart failure (CHF) of ischemic origin, with low left ventricle ejection fraction (LV EF), a violation of NO metabolism is noted. Decrease of L‑arginine concentration leads to decrease in endothelial NO-synthase activity, and increase of macrophage NO-synthase activity leads to high concentration of nitric oxide and its stable metabolites in peripheral blood. Endothelial vasomotor dysfunction is associated with decrease of vasodilatation and even paradox vasoconstriction (in our study in 10 patients (3.3%)). Inclusion of L‑arginine to standard therapy of CHF gives additional positive effect on improvement of metabolism of nitric oxide and endothelial vasomotor function.

Achieving Long-Term Biocompatible Silicone via Covalently Immobilized S-Nitroso- N-acetylpenicillamine (SNAP) That Exhibits 4 Months of Sustained Nitric Oxide Release.

Ever since the role of endogenous nitric oxide (NO) in controlling a wide variety of biological functions was discovered approximately three decades back, multiple NO-releasing polymeric materials have been developed. However, most of these materials are typically short lived due to the inefficient incorporation of the NO donor molecules within the polymer matrix. In the present study, S-nitroso- N-acetyl penicillamine (SNAP) is covalently attached to poly(dimethylsiloxane) (PDMS) to create a highly stable nitric oxide (NO) releasing material for biomedical applications. By tethering SNAP to the cross-linker of PDMS, the NO donor is unable to leach into the surrounding environment. This is the first time that a sustainable NO release and bacterial inhibition for over 125 days has been achieved by any NO-releasing polymer with supporting evidence of potential long-term hemocompatibility and biocompatibility. The material proves to have very high antibacterial efficacy against Staphylococcus aureus by demonstrating a 99.99% reduction in the first 3 days in a continuous flow CDC bioreactor, whereas a similar inhibitory potential of 99.50% was maintained by the end of 1 month. Hemocompatibility of SNAP-PDMS was tested using a rabbit extracorporeal circuit (ECC) model over a 4 h period. Thrombus formation was greatly reduced within the SNAP-PDMS-coated ECCs compared to the control circuits, observing a 78% reduction in overall thrombus mass accumulation. These results demonstrate the potential of utilizing this material for blood and tissue contacting biomedical devices in long-term clinical applications where infection and unwanted clotting are major issues.

THE RELATIONSHIP BETWEEN LEVELS OF ALDOSTERONE, ESTRADIOL AND SERUM MARKERS OF ENDOTHELIAL DYSFUNCTION IN HYPERTENSIVE WOMEN

Objective: To study the relationship between plasma levels of aldosterone, estradiol and serum markers of endothelial dysfunction (ED) such as stable nitric oxide metabolites NO2-+NO3- (NOx), endothelin-1 (ET-1), homocysteine (HC), von Willebrand factor (vWF) in nondiabetic women with essential hypertension (EH). Design and method: We examined 79 hypertensive, nondiabetic women (mean age 51,4 ± 6,5y, mean EH duration 8,5 ± 7,6y). 28% of the group were smokers, 54% were obese, 76% - with dyslipidemia. Regular menstrual function had 30% of the women, the rest of the group – postmenopausal (median duration of postmenopause was 5,7 ± 3,5y). Circulating NOx levels were studied by spectrophotometry, ET-1, HC, vWF levels – by immunoenzyme assay, aldosterone and estrogen levels - by immunoenzyme assay. Statistical analysis was done using the Statistica 10.0 software. Results: We compared the levels of ED markers in women with a normal (56%), and elevated levels of aldosterone (44%), as well as in women with a normal (62%) and low levels of estradiol (38%). Women with hiperaldosteronemia had higher concentration of NOx (45.3 ± 17.6 and 38.8 ± 16.5 mmol/l, respectively, p < 0.05), E-1 (1.4 ± 1.1 and 0.9 ± 0.8 fmol/l, respectively, p < 0.05) and vWF (1.6 ± 0.8 and 1.3 ± 0.9 mg/dl, respectively, p < 0.05). Aldosterone levels correlated with NOx (r = 0.36, p < 0.05), E-1 (r = 0.3, p < 0.05) and vWF (r = 0.34, p < 0.05) levels. Women with hypoestrogenemia had higher NOx (46.3 ± 16.9 and 37.5 ± 16.0 mmol/l, respectively, p < 0.05), E-1 (1.5 ± 1.1 and 0.8 ± 0.4 fmol/l, respectively, p < 0.05) and vWF (1.6 ± 0.9 and 1.2 ± 0.7 mg/dl, respectively, p < 0.05) levels as well. Estradiol levels correlated with NOx (r = -0.6, p < 0.05) and vWF (r = -0.5, p < 0.05) levels. Conclusions: Our results suggest that women in perimemopausal period demonstrate hormonal disorders with elevation of aldosterone level and decline of estrogen level, which are related to the increase of a number of substances considered as the markers of endothelial dysfunction.

Abstract P185: Prognostic Value of Endothelial Markers in Hypertensive Nondiabetic Patients

Aim: to study the prognostic value of the serum levels of stable nitric oxide metabolites (NOx), endothelin-1 (E1), homocystein (HC), von Willebrand factor (Wf), tissue plasminogen activator (tPA), in hypertensive nondiabetic patients without cardiovascular disease. Methods: 124 patients with hypertension (HTN), without diabetes were enrolled, the mean age was 51.4±6.5y, the mean duration of HTN was 8.5±7.6 y, 36 % were males, 35% were smokers, 54% were obese. The cardiovascular risk was estimated according to the SCORE (Systematic Coronary Risk Evaluation) system. Plasma NOx levels were determined by spectrophotometry, E1, HC, Wf, tPA levels by enzyme immunoassay. The follow-up period was 8±1.1y. Statistical analysis was done using the SPSS 11.1 software. Results: On initial investigation all patients were stratified according to the SCORE risk levels. The increase of SCORE risk levels were associated with the elevation of serum NOx, E1, HC, and Wf concentrations. The mean plasma NOx concentration increased along with the SCORE risk level: it was 36.4±12.7 in low risk, 41.1±15.7 in moderate risk, 44.9±19.8 in high risk, and 50.4±19.1 umol/L in very high risk categories (&lt;0.05 between the low and high risk groups). The tPA levels did not differed in relation to the SCORE risk estimates. The SCORE risk level correlated with serum concentrations of NOx (r=0.74, p=0.0001), HC (r=0.54, p=0.0001), and Wf (r=0.43, p=0.001). Conclusions: The stable nitric oxide metabolites, homocystein, and von Willebrand factor are the markers of oxidative/nitrosative stress severity. Our results are indicative that this substances may be of prognostic value in hypertensive nondiabetic patients.

THE STATE OF NITROXIDE PRODUCTION FUNCTION OF ENDOTHELIUM AND LEFT VENTRICLE HYPERTROPHY IN ARTERIAL HYPERTENSION

Aim . To assess levels of stable nitric oxide metabolites (NO) in plasma of arterial hypertension (AH) patients not taking systematic antihypertension therapy, in accordance with the presence and absence of the left ventricle hypertrophy (LVH). Material and methods . Totally, 124 AH patients included: 45 males, 79 females, mean age — 51,4±6,5 y.o., mean duration of AH — 7,9±7,3 y. Controls included 25 healthy persons: 10 males, 15 females; mean age — 48,2±7,8 y.o. Transthoracal echocardiography was done by standard method. Myocardium remodelling types were evaluated by the Ganau A (1992) criteria. Concentration of NO in plasma was measured by spectrophotometry. Statistics was done with Statistica 8.0 software. Results . In AH patients the level of NO was significantly higher than in controls — 43,2±21,7 mcM/L vs 28,3±9,6 mcM/L (p<0,05). There was positive correlation of NO with the fact of AH (r=0,31, p<0,05). In AH patients LVH was diagnosed in 66,7%. In AH with LVH patients concentration of NO was significantly higher than in AH non-LVH — 49,9±19,3 vs 39,8±18,3 mcM/L, respectively, (р<0,05) and in controls. There were direct correlations in AH patients, with NO and myocardial mass index of the left ventricle (LV) (r=0,44, р<0,05), with interventricular septum thickness (r=0,36, р<0,05), posterior LV wall thickness (r=0,44, р<0,05). In the subgroup of AH patients with normal LV geometry there were the lowest NO levels — 35,1±17,3 mcM/L. In subgroups of AH patients with concentric remodeling, eccentric remodeling and concentric LVH, levels of NO were significantly higher than in controls (p<0,05). Higher NO levels were found in AH patients with concentric LVH (53,9±19,1 mcM/L). Conclusion . In AH patients of I-II stages there were raised NO levels. In AH patients with LVH concentration of NO is significantly higher than in non-LVH. There is correlation with myocardium mass index of LV and NO (r=0,44, p<0,05). The highest levels of NO were found in AH patients with concentric LVH.

IMPACT OF CHRONIC ARTERIAL HYPERTENSION ON CLINICAL AND METABOLIC NEONATAL ADAPTATION

Aim. To assess the impact of chronic arterial hyper-tension on clinical and metabolic adaptation of fullterm newborns. Methods. 65 full-term neonates born to women with chronic arterial hypertension were included in the study. 42 neonates born to women with arterial hypertension stage I were enrolled into Group 1, and 23 neonates born to mothers with arterial hypertension stage II were included in Group 2. Levels of renin, angiotensin II, aldosterone, natriuretic peptides, endothelin-1 in umbilical cord blood and peripheral blood were measured with the ELISA. Stable nitric oxide metabolites levels were measured using the Griess assay. Results. Chronic high blood pressure during pregnancy has been found to affect fetal central nervous system and cardiovascular system. Early neonatal period in infants of women with chronic arterial hypertension is associated with a high incidence of perinatal CNS injury, continuing with little change during the first three months of life. The features of the cardiovascular system in neonates of women with arterial hypertension stage II include hypertension and tachycardia at birth, violation of atrioventricular conduction on the first three days of life, open patent foramen ovale up to the first three months of life, whereas neonates born to women with arterial hyper-tension stage I have hypotension on the first day of life. Elevated levels of angiotensin II in neonates born to women with chronic arterial hypertension at birth and reduced levels of endogenous nitrite in the first three months of life suggest the activation of the renin-angiotensin-aldosterone system in the antenatal period, which may cause endothelial dysfunction in early infancy. Conclusions. 1. Chronic high blood pressure in pregnancy is as-sociated with perinatal CNS damage in the newborn, continued during the first three months of life. 2. Stage 1 of hypertension in pregnancy associated with hypotension in newborns on the first day of life; and stage 2 of hypertension in pregnancy associated with hypertension and tachycardia newborn at birth, a violation of his atrioventricular conduction on the 3rd day of life and preservation until the age of three open oval window. 3. Chronic high blood pressure in pregnancy is as-sociated with an increase in cord blood levels of angiotensin II decrease in peripheral blood concentration of endogenous nitrite in the age of three months.

Tick-borne neuroinfections: Clinical characteristics, immunopathogenesis, and new pharmacotherapeutic strategies

To study the semiotics of neurological lesions in patients with tick-borne encephalitis, Ixodes tick-borne borreliosis (ITBB) and mixed infection (MI), their immunopathogenesis, and the possibilities of current pathogenetic pharmacological correction. A total of 220 patients with tick-borne encephalitis, ITBB, and MI concurrent with the syndromes of central nervous system lesions were examined. The immunological studies encompassed the examination of mononuclear cells in the cerebrospinal fluid (CSF), the population and subpopulation composition of lymphocytes, and nitroxidergic processes in the serum and CSF from the total level of final stable nitric oxide metabolites. For pharmacotherapeutic correction, the metabolic drug cytoflavin was used as newly indicated. Cytofluorometric analysis of the CSF cellular composition showed the mononuclear cell predominance of CD3+ (58.6%), CD4+ (57.2%), CD8+ (16.8%) lymphocytes and monocytes (34.4%), which expressed the phenotypic marker CD14+. This reflects the nature of a local immune response: an increase in the immunoregulatory index CD4+/CD8+ from 3.4 to 5.6, respectively, while the normal proportion of these cells in the blood ranges from 1.5 to 2.2. CSF lymphocytes were found to be ready for Fas-mediated apoptosis dependent on the receptor (CD95+ was 64.3%).There was a correlation using the pair correlation coefficient between the total concentration of the metabolites of the nitroxide molecule and the percentage of CD14+ (r=0.5; p<0.05). The paired Wilcoxon test was used to analyze serum NO2, NO3, and NOx, which revealed significant differences in nitrites [2.70 (1.90, 2.95; p=0.001)] and total NO metabolites [18.00 (18.00, 22.60; p=0.006)] and statistically significant changes in nitrates [13.29 (15.70. 20.30; p=0.075)] in patients receiving cytoflavin infusions. The immune response of Th-1 forms between the CSF phagocytic, antigen-presenting, and immunocompetent lymphocytes in patients with tick-borne neuroinfections. The use of cytoflavin as an agent for neurotransmitter support to correct nitroxidergic processes is pathogenetically justified.

PS 08-81 ENDOTHELIAL MARKERS IN HYPERTENSIVES WITH SUBCLINICAL ORGAN DAMAGE

Objective: To investigate stable nitric oxide metabolites (NOx), endothelin-1(ET-1), homocysteine (HC), von Willebrand factor (vWF) levels in patients with essential hypertension (EH) and subclinical organ damage (SOD). Design and Method: We included124 patients (45 men and 79 women) with untreated EH (mean age 51.4 ± 6y, mean EH duration 8.5 ± 7y) and 25 healthy volunteers (10 men and 15 women) with comparable age (47.2 ± 7y). Plasma NOx level was measured by spectrophotometry, ET-1, HC, vWF levels were studied with the help of immunoenzyme assay. Results were processed with Statistica 8.0 software. Results: Microalbuminuria (MAU) was detected in 22% of hypertensives, left ventricular hypertrophy (LVH) in 37% of them. NOx, ET-1, HC, vWF levels were significantly higher in hypertensives (43,2 ± 21 μmol/l, 1,2 ± 0,9 fmol/l, 17,9 ± 7,8 μmol/l, 1,3 ± 0,6 mg/dl, accordingly) than in controls (28,3 ± 9 μmol/l, 0,6 ± 0,5 fmol/l, 10,7 ± 5,8 μmol/l, 1,01 ± 0,7 mg/dl, accordingly) (р < 0,05). The concentration of NOx and ET-1were significantly higher in patients with MAU in comparison to others (46,5 ± 22, 31,3 ± 12 μmol/l and 1,3 ± 0,8, 0,5 ± 0,6 fmol/l, accordingly, р < 0,05). NOx, ET-1 levels were correlated with the presence of MAU (r = 0,48, р = 0,007; r = 0,37 р = 0,03, accordingly). HC, vWF levels did not differ between hypertensives with MAU and normoalbuminuria (р > 0,05). In patients with LVH NOx, ET-1, HC, vWF levels were significantly higher (49,9 ± 19 μmol/l, 1,3 ± 1,1 fmol/l, 20,1 ± 7,6 μmol/l, 1,5 ± 0,7 mg/dl, accordingly) than in those without it (39,8 ± 18 μmol/l, 0,8 ± 0,9 fmol/l, 16,5 ± 7,1 μmol/l, 1,2 ± 0,7 mg/dl accordingly), (р < 0,05). NOx concentration correlated with left ventricular mass index (r = 0,44 р = 0,005), interventricular septum thickness (r = 0,36 р = 0,02) and left ventricle posterior wall thickness (r = 0,44 р = 0,006). The vWF level was correlated with the presence of LVH (r = 0,45, р < 0,009). Conclusions: NOx, ET-1, HC, vWF were elevated in hypertensives with LVH, and NOx, ET-1 levels were higher in hypertensives with MAU. The levels of studied endothelial markers were directly correlated with presence of LVH and MAU

Stable Nitric Oxide Metabolites Levels in Hypertensive Patients With Obesity and High Leptin Level

to investigate levels of the stable nitric oxide metabolites (NOx) in hypertensive patients with obesity and hyperleptinemia. We examined 124 untreated patients (45 men and 79 women) with essential hypertension (EH) (mean age 51.4+/-6.5 years, mean hypertension duration 8.5+/-7.6 years, 64% with visceral obesity) and 25 healthy volunteers (10 men and 15 women with comparable age). NOx levels were significantly higher in hypertensives (43.18+/-21 mol/l) then in controls (28.3+/-9.6 mol/l; p=0.01). Obese hypertensives had lower NOx concentration than nonobese hypertensives (38.8+/-17.9 and 48.5+/-24.7 mol/l, respectively; <0.05). With increase of degree of obesity NOx levels decreased significantly (r=-0.3; p<0.05). NOx levels correlated with presence (r=-0.44; p<0,05) and degree of obesity (r=-0.3; p<0.05). Hypertensives with high leptin levels had lower NOx concentration (29+/-12.2 mol/l), compared to hypertensives with normal leptin levels (34. 7+/-10.5 mol/l) (p<0.05).

Single‐walled carbon nanotubes modulate cardiovascular control in rats

Effect of water dispersible single‐walled carbon nanotubes on the medullary cardiovascular control was studied in normotensive (control) and spontaneously hypertensive rats using physiological and biochemical approaches. We have shown for the first time the possible contribution of nitric oxide (NO) to single‐walled carbon nanotube‐induced effects in the cardiovascular nuclei of the medulla oblongata (the lateral reticular nucleus and nucleus ambiguous). The data of biochemical experiments indicate that single‐walled carbon nanotubes added to the medulla oblongata homogenates induce an enhancement of constitutive nitric oxide‐synthase (cNOS) activity, which is mostly neuronal nitric oxide‐synthase (nNOS) in the brain, and an increase in the level of nitrite (NO–2), a stable nitric oxide metabolite which serves nitric oxide bioavailability marker. In physiological experiments, it has been revealed that effects of single‐walled carbon nanotube injection in the cardiovascular nuclei under study are attenuated after preliminary nNOS inhibiting. An analysis of single‐walled carbon nanotube‐induced changes in the levels of malonic dialdehyde, an oxidative stress marker, as well as the levels of reactive nitrogen species (pools of nitrate anions), and the activity of Ca2+‐independent inducible nitric oxide synthase (iNOS) has indicated that single‐walled carbon nanotubes used in the study do not promote oxidative and nitrosative stress in control and spontaneously hypertensive rats.

Long-term variability of exhaled nitric oxide measurements

Measurement of fractional exhaled nitric oxide (FENO) is recommended as an adjunct in the diagnosis of eosinophilic airway inflammation, to determine the likelihood of corticosteroid responsiveness, to monitor therapy, and to assess adherence to inhaled corticosteroid therapy. The American Thoracic Society Guidelines for the interpretation of FENO concentrations identify cut points in children of greater than 35 parts per billion (ppb) for eosinophilic airway inflammation and less than 20 ppb for no inflammation. For adults, the guidelines recommend greater than 50 ppb and less than 25 ppb, respectively. The NIOX MINO (Aerocrine AB, Solna, Sweden) is a commonly used portable method of analyzing FENO that does not require calibration. The accuracy and precision of this device were largely determined by extensive in vitro testing for US Food and Drug Administration clearance. The same is true for its successor, the NIOX VERO. The clinical study in the MINO FDA submission was a single measurement before and after beginning inhaled corticosteroids, which demonstrated a decrease in FENO. Other published clinical studies are single visit comparisons with other methods or multiple technicians. Only one study compared 2 measurements on different days. Because there are no published reports on the long-term reproducibility of devices used to measure FENO, we undertook the following study. We analyzed 451 quality control measurements obtained over a 2-year period from 5 devices. There were 5 nonasthmatic technicians (quality control subjects) who performed these measurements on each day that the device was used for a clinical study or patient care (see Table E1 in this article’s Online Repository at www.jaci-inpractice.org for more details). All control subjects met the manufacturer’s criteria, which included >18 years old, no ongoing cold or known airway disorder, nonsmoker, expected stable exhaled nitric oxide values between 5 and 40 ppb during the qualification period, and preferably no allergies (except seasonal) or asthma. To obtain a control FENO measurement, each technician was required to empty his or her lungs by slowly exhaling and then forming a tight seal around the mouthpiece, making sure not to let the air leak out. Then, they inhaled to total lung capacity and exhaled forcefully for approximately 10 seconds through the mouthpiece while responding to sound and light cues on the LCD to guide the rate of exhalation. The general linear model procedure was used to determine whether there was a device*subject interaction. Because the interaction was significant (P .05). Measurements for subjects 3-5 who used device 5 were 31.79 (7.2), 11.51 (4.2), and 15.0 (4.1) ppb, respectively (Figure 2). Measurements for subject 3 were significantly higher than those for subjects 4 and 5 (P < .0001). Eighty-two percent of her values were above 25 ppb. The NIOX MINO portable device employing an electrochemical methodology was cleared by FDA as “substantially equivalent” to the chemiluminescence stationary method (NIOX), largely based on extensive in vitro testing using certified nitric oxide in nitrogen calibration gas. Similarly, the new NIOX VERO was cleared in the same way as “substantially

Influence of metabolic syndrome components on the level of nitric oxide stable metabolites in patients with essential hypertension

Objective. To investigate levels of the stable nitric oxide metabolites (NOx) in relation to different components of the metabolic syndrome (MS) in essential hypertension (EH).Methods. We examined 124 untreated patients with EH and 25 healthy volunteers with comparable age.Results. NOx levels were significantly higher in hypertensives (43.18±21, mol/l) then in controls (28.3±9.6 mol/l); p

Synthesis and characterization of S-nitrosoglutathione-oligosaccharide-chitosan as a nitric oxide donor

Objectives: The aim of this work is to synthesize a novel stable and biodegradable nitric oxide (NO) donor polymer based on a chitosan backbone. This polymer needed to be linked to glutathione (GSH), which was nitrosated in a second step. This polymer has been developed as an NO delivery platform that could be further evaluated for an oral delivery in Crohn’s disease.Methods: The new polymer (named S-nitrosoglutathione-oligosaccharide-chitosan or SNOC) was obtained using a two-step procedure involving the linkage of GSH to chitosan via an amidine reaction followed by a post-nitrosation with NaNO2. The GSH linkage was assessed using NMR, FTIR and an Ellman’s test, whereas the final NO amount was determined by the Griess and Saville method.Results: Polymers with different numbers of NO groups were obtained (159.04 ± 64.16 µmol/g of polymer for SNOC G1 and 525.08 ± 151.35 µmol/g of polymer for SNOC G2) depending on the procedure used for production. When tested in an Ussing chamber, SNOC G2 had a sustained release of NO and nitrites for at least 6 h.Conclusion: We believe that this type of polymer is adapted for the development of various formulations, including microparticles.

PLASMA LEVELS OF NITRIC OXIDE METABOLITES ARE LOWER IN HFPEF SUBJECTS COMPARED TO HFREF AND HYPERTENSIVES

Stable plasma nitric oxide metabolites (NOx), predominantly composed of nitrate, are markers of endogenous nitric oxide (NO) production, NO utilization, and dietary intake and may be indicators of vascular health. We enrolled subjects undergoing a clinically-indicated cardiac MRI. Plasma NOx levels