Association between nitric oxide synthase (NOS3) gene polymorphisms and diabetic nephropathy: An updated meta-analysis.

Polymorphisms located within NOS3 gene have been investigated as susceptibility variants for diabetic nephropathy (DN) in type 2 diabetes mellitus (T2DM) in a large number of studies. However, these previous articles yielded inconsistent results and we aimed at elucidating the impact of NOS3 variants on DN risk in T2DM by conducting an updated systematic data synthesis. A total of 36 studies (12,807 participants) were selected for qualitative data synthesis, while 33 records with 11,649 subjects were included in the meta-analysis. The pooled analysis demonstrated the association of minor alleles of rs2070744 and rs1799983 with an increased susceptibility to DN (P < 0.001 and P = 0.015 for allelic model, respectively). For both of these variants, a significant effect of subgrouping according to ethnicity was found. Rs869109213 displayed an association with DN susceptibility, with pooled effect measures indicating a predisposing effect of the minor allele a (Prec = 0.002, ORrec = 1.960, 95%CI 1.288-2.983; Paavs. bb = 0.001, ORaavs. bb = 2.014, 95%CI 1.316-3.083). These findings support the effects of NOS3 variants on the risk of developing DN in T2DM.

Low HDL cholesterol and the eNOS Glu298Asp polymorphism are associated with inducible myocardial ischemia in patients with suspected stable coronary artery disease.

BACKGROUND: The endothelial nitric oxide synthase (eNOS) gene deficiency is known to cause impaired coronary vasodilating capability in animal models. In the general clinical population, the eNOS gene polymorphisms, able to affect eNOS activity, were associated with cardiometabolic risk features and prevalence of coronary artery disease (CAD). AIM: To investigate the association of eNOS Glu298Asp gene polymorphism, cardiometabolic profile, obstructive CAD and inducible myocardial ischemia in patients with suspected stable CAD. METHODS: A total of 506 patients (314 males; mean age 62 ± 9 years) referred for suspected CAD was enrolled. Among these, 325 patients underwent stress ECG or cardiac imaging to assess the presence of inducible myocardial ischemia and 436 patients underwent non-invasive computerized tomography or invasive coronary angiography to assess the presence of obstructive CAD. Clinical characteristics and blood samples were collected for each patient. RESULTS: In the whole population, 49.6% of patients were homozygous for the Glu298 genotype (Glu/Glu), 40.9% heterozygotes (Glu/Asp) and 9.5% homozygous for the 298Asp genotype (Asp/Asp). Obstructive CAD was documented in 178/436 (40.8%) patients undergoing coronary angiography while myocardial ischemia in 160/325 (49.2%) patients undergoing stress testing. Patients with eNOS Asp genotype (Glu/Asp + Asp/Asp) had no significant differences in clinical risk factors and in circulating markers. Independent predictors of obstructive CAD were age, gender, obesity, and low HDL-C. Independent predictors of myocardial ischemia were gender, obesity, low HDL-C and Asp genotype. In the subpopulation in which both stress tests and coronary angiography were performed, the Asp genotype remained associated with increased myocardial ischemia risk after adjustment for obstructive CAD. CONCLUSION: In this population, low-HDL cholesterol was the only cardiometabolic risk determinant of obstructive CAD. The eNOS Glu298Asp gene polymorphism was significantly associated with inducible myocardial ischemia independently of other risk factors and presence of obstructive CAD.

Reversal of Pulmonary Hypertension in a Human-Like Model: Therapeutic Targeting of Endothelial DHFR.

BACKGROUND: Pulmonary hypertension (PH) is a progressive disorder characterized by remodeling of the pulmonary vasculature and elevated mean pulmonary arterial pressure, resulting in right heart failure. METHODS: Here, we show that direct targeting of the endothelium to uncouple eNOS (endothelial nitric oxide synthase) with DAHP (2,4-diamino 6-hydroxypyrimidine; an inhibitor of GTP cyclohydrolase 1, the rate-limiting synthetic enzyme for the critical eNOS cofactor tetrahydrobiopterin) induces human-like, time-dependent progression of PH phenotypes in mice. RESULTS: Critical phenotypic features include progressive elevation in mean pulmonary arterial pressure, right ventricular systolic blood pressure, and right ventricle (RV)/left ventricle plus septum (LV+S) weight ratio; extensive vascular remodeling of pulmonary arterioles with increased medial thickness/perivascular collagen deposition and increased expression of PCNA (proliferative cell nuclear antigen) and alpha-actin; markedly increased total and mitochondrial superoxide production, substantially reduced tetrahydrobiopterin and nitric oxide bioavailabilities; and formation of an array of human-like vascular lesions. Intriguingly, novel in-house generated endothelial-specific dihydrofolate reductase (DHFR) transgenic mice (tg-EC-DHFR) were completely protected from the pathophysiological and molecular features of PH upon DAHP treatment or hypoxia exposure. Furthermore, DHFR overexpression with a pCMV-DHFR plasmid transfection in mice after initiation of DAHP treatment completely reversed PH phenotypes. DHFR knockout mice spontaneously developed PH at baseline and had no additional deterioration in response to hypoxia, indicating an intrinsic role of DHFR deficiency in causing PH. RNA-sequencing experiments indicated great similarity in gene regulation profiles between the DAHP model and human patients with PH. CONCLUSIONS: Taken together, these results establish a novel human-like murine model of PH that has long been lacking in the field, which can be broadly used for future mechanistic and translational studies. These data also indicate that targeting endothelial DHFR deficiency represents a novel and robust therapeutic strategy for the treatment of PH.

Crystallographic and Computational Insights into Isoform-Selective Dynamics in Nitric Oxide Synthase.

In our efforts to develop inhibitors selective for neuronal nitric oxide synthase (nNOS) over endothelial nitric oxide synthase (eNOS), we found that nNOS can undergo conformational changes in response to inhibitor binding that does not readily occur in eNOS. One change involves movement of a conserved tyrosine, which hydrogen bonds to one of the heme propionates, but in the presence of an inhibitor, changes conformation, enabling part of the inhibitor to hydrogen bond with the heme propionate. This movement does not occur as readily in eNOS and may account for the reason why these inhibitors bind more tightly to nNOS. A second structural change occurs upon the binding of a second inhibitor molecule to nNOS, displacing the pterin cofactor. Binding of this second site inhibitor requires structural changes at the dimer interface, which also occurs more readily in nNOS than in eNOS. Here, we used a combination of crystallography, mutagenesis, and computational methods to better understand the structural basis for these differences in NOS inhibitor binding. Computational results show that a conserved tyrosine near the primary inhibitor binding site is anchored more tightly in eNOS than in nNOS, allowing for less flexibility of this residue. We also find that the inefficiency of eNOS to bind a second inhibitor molecule is likely due to the tighter dimer interface in eNOS compared with nNOS. This study provides a better understanding of how subtle structural differences in NOS isoforms can result in substantial dynamic differences that can be exploited in the development of isoform-selective inhibitors.

Liquid plasma promotes angiogenesis through upregulation of endothelial nitric oxide synthase-induced extracellular matrix metabolism: potential applications of liquid plasma for vascular injuries.

BACKGROUND: Applications of nonthermal plasma have expanded beyond the biomedical field to include antibacterial, anti-inflammatory, wound healing, and tissue regeneration. Plasma enhances epithelial cell repair; however, the potential damage to deep tissues and vascular structures remains under investigation. RESULT: This study assessed whether liquid plasma (LP) increased nitric oxide (NO) production in human umbilical vein endothelial cells by modulating endothelial NO synthase (eNOS) phosphorylation and potential signaling pathways. First, we developed a liquid plasma product and confirmed the angiogenic effect of LP using the Matrigel plug assay. We found that the NO content increased in plasma-treated water. NO in plasma-treated water promoted cell migration and angiogenesis in scratch and tube formation assays via vascular endothelial growth factor mRNA expression. In addition to endothelial cell proliferation and migration, LP influenced extracellular matrix metabolism and matrix metalloproteinase activity. These effects were abolished by treatment with NG-L-monomethyl arginine, a specific inhibitor of NO synthase. Furthermore, we investigated the signaling pathways mediating the phosphorylation and activation of eNOS in LP-treated cells and the role of LKB1-adenosine monophosphate-activated protein kinase in signaling. Downregulation of adenosine monophosphate-activated protein kinase by siRNA partially inhibited LP-induced eNOS phosphorylation, angiogenesis, and migration. CONCLUSION: The present study suggests that LP treatment may be a novel strategy for promoting angiogenesis in vascular damage. Video Abstract.

Endothelial nitric oxide synthase (eNOS) gene polymorphism (Glu298asp) and nitric oxide (NO) levels in patients with ST-segment elevation myocardial infarction (STEMI).

BACKGROUND: Genetic polymorphism in endothelial Nitric Oxide Synthase (eNOS) are associated with occurrence of multiple cardiovascular diseases (CVDs). METHODS: This study included 300 young ST-segment elevation myocardial infarction (STEMI) patients and 300 healthy controls. STEMI patients were divided into two groups: premature coronary artery disease [CAD] (STEMI<40 years of age) and older STEMI (>40 years of age). Genetic polymorphisms in the eNOS gene (894G/T) was evaluated in both subjects and controls. Plasma levels of nitric oxide (NO) were estimated for both patients as well as controls. RESULTS: Mean age of the study population was 49.7 ± 9.2 years with premature CAD being present in 58 (19.3 %) patients. No significant difference at genotypic (P = 0.589, odds ratio (OR) = 0.9, 95 % CI = 0.6-1.6) and allelic level (P = 0.173, OR = 1.2, 95 % CI = 0.9-1.4) was observed between STEMI patients and healthy controls. Genotype 894 TT had significantly higher frequency in STEMI patients >40 years (P = 0.047, OR: 2.5; 95 % CI = 1.0-6.0). No significant difference at genotypic (P = 0.279) and allelic level (P = 0.493) was observed between premature CAD (STEMI age <40 years) and healthy controls. NO levels (131 ± 59.6 µM vs 118.11 ± 49.96 µM; P = 0.001) was significantly higher in healthy controls as compared to STEMI patients >40 years of age (P= 0.001). CONCLUSION: There was significant association of eNOS gene polymorphism Glu298Asp with STEMI patients > 40 years. However, this association was not observed in premature CAD patients. Lower levels of NO in STEMI patients >40 years suggests its potential role as a marker of CVD.

Danhong formula alleviates endothelial dysfunction and reduces blood pressure in hypertension by regulating MicroRNA 24 - Phosphatidylinositol 3-Kinase-Serine/Threonine Kinase- Endothelial Nitric Oxide Synthase axis.

ETHNOPHARMACOLOGICAL RELEVANCE: Essential hypertension (EH) is one of the important risk factors of cardio-cerebrovascular diseases, and it can significantly increase the incidence and mortality of acute myocardial infarction, cerebral infarction and hemorrhage. Danhong Formula (DHF) was consisting of Radix et Rhizoma Salviae Miltiorrhizae (Salvia miltiorrhiza Bge., Labiatae, Danshen in Chinese) and Flos Carthami (Carthamus tinctorius L., Compositae, Honghua in Chinese) (Plant names have been checked with http://www.the plant list.org on June 28th, 2023) was approved by State Food and Drug Administration of China, that has been used for thousands of years in the treatment of cardiovascular diseases in China with proven safety and efficacy. Though our previous studies have found that DHF improved endothelial dysfunction (ED) and decreased high blood pressure (BP), the underlying mechanisms of its antihypertensive effect still remain unclear. AIM OF THE STUDY: This study investigated whether DHF regulated MicroRNA 24- Phosphatidylinositol 3-Kinase-Serine/Threonine Kinase- Endothelial Nitric Oxide Synthase (miR-24 - PI3K/AKT/eNOS) axis to produce antihypertensive effect and improve endothelial dysfunction. MATERIALS AND METHODS: Firstly, the chemical components of DHF were analyzed by UHPLC-MS. After that, BP was continuously monitored within the 1st, 3rd, and 4th week in SHR to evaluate the antihypertensive effect of DHF intraperitoneal injection. In addition, not only the contents of serum nitric oxide (NO), prostacyclin (PGI2), and angiotensin II (Ang II) were detected, but also the isolated aorta ring experiment was conducted to evaluate the vasomotoricity to evaluate of DHF on improving endothelial dysfunction. Key proteins or mRNA expression associated with miR-24 - PI3K/AKT/eNOS axis in aorta were detected by capillary Western blot, immunohistochemistry or RT-PCR to explore the underlying mechanisms. Index of NO, Ang II PGI2 and key proteins or mRNA expression were also conducted in miR-24-3p over-expression HUVECs model. RESULTS: Compared with SHR control group, DHF (4 mL/kg/day, 2 mL/kg/day, 1 mL/kg/day) treatment significantly reduced high BP in SHR and selectively increased acetylcholine (Ach) induced vasodilation, but not sodium nitroprusside (SNP) in a manner of concentration dependency in isolated aorta ring. DHF (4 mL/kg/day, 1 mL/kg/day) treatment was accompanying an increment of NO and PGI2, and lowering AngII in SHR. Moreover, DHF treatment significantly up-regulated expression of p-PI3K, p-AKT, mTOR, eNOS and p-eNOS, but down-regulated miR-24-3p expression in aorta. Compared with miR-24-3p over-expression HUVECs model group, DHF treatment inhibited miR- 24-3p expression and up-regulated p-PI3K, p-AKT, mTOR and eNOS mRNA expression. Similarly, DHF treatment increased PI3K, AKT, mTOR and eNOS protein expression in HUVECs by Western blot. CONCLUSIONS: These findings suggest that DHF alleviates endothelial dysfunction and reduces high BP in SHR mediated by down-regulating miR-24 via ultimately facilitating up-regulation of PI3K/AKT/eNOS axis. This current study firstly demonstrates a potential direction for antihypertensive mechanism of DHF from microRNA aspect and will promote its clinical applications.

Lymphocyte-Specific Protein 1 Regulates Expression and Stability of Endothelial Nitric Oxide Synthase.

Nitric oxide (NO), synthesized by endothelial nitric oxide synthase (eNOS), plays a critical role in blood pressure regulation. Genome-wide association studies have identified genetic susceptibility loci for hypertension in human lymphocyte-specific protein 1 (LSP1) gene. LSP1 is recognized as modulator of leukocyte extravasation, and endothelial permeability, however, the role of LSP1 in regulation of NO signaling within endothelial cells (ECs) remains unknown. The present study investigated the role of LSP1 in the regulation of eNOS expression and activity utilizing human macrovascular ECs in vitro and LSP1 knockout (KO) mice. In ECs, specific CRISPR-Cas9 genomic editing deleted LSP1 and caused downregulation of eNOS expression. LSP1 gain-of-function through adenovirus-mediated gene transfer was associated with enhanced expression of eNOS. Co-immunoprecipitation and confocal fluorescence microscopy revealed that eNOS and LSP1 formed a protein complex under basal conditions in ECs. Furthermore, LSP1 deficiency in mice promoted significant upregulation and instability of eNOS. Utilizing a mass-spectrometry-based bottom-up proteomics approach, we identified novel truncated forms of eNOS in immunoprecipitates from LSP1 KO aortae. Our experimental data suggest an important role of endothelial LSP1 in regulation of eNOS expression and activity within human ECs and murine vascular tissues.

Nur77 mitigates endothelial dysfunction through activation of both nitric oxide production and anti-oxidant pathways.

BACKGROUND: Nur77 belongs to the member of orphan nuclear receptor 4A family that plays critical roles in maintaining vascular homeostasis. This study aims to determine whether Nur77 plays a role in attenuating vascular dysfunction, and if so, to determine the molecular mechanisms involved. METHODS: Both Nur77 knockout (Nur77 KO) and Nur77 endothelial specific transgenic mice (Nur77-Tg) were employed to examine the functional significance of Nur77 in vascular endothelium in vivo. Endothelium-dependent vasodilatation to acetylcholine (Ach) and reactive oxygen species (ROS) production was determined under inflammatory and high glucose conditions. Expression of genes was determined by real-time PCR and western blot analysis. RESULTS: In response to tumor necrosis factor alpha (TNF-α) treatment and diabetes, the endothelium-dependent vasodilatation to Ach was significantly impaired in aorta from Nur77 KO as compared with those from the wild-type (WT) mice. Endothelial specific overexpression of Nur77 markedly prevented both TNF-α- and high glucose-induced endothelial dysfunction. Compared with WT mice, after TNF-α and high glucose treatment, ROS production in aorta was significantly increased in Nur77 KO mice, but it was inhibited in Nur77-Tg mice, as determined by dihydroethidium (DHE) staining. Furthermore, we demonstrated that Nur77 overexpression substantially increased the expression of several key enzymes involved in nitric oxide (NO) production and ROS scavenging, including endothelial nitric oxide synthase (eNOS), guanosine triphosphate cyclohydrolase 1 (GCH-1), glutathione peroxidase-1 (GPx-1), and superoxide dismutases (SODs). Mechanistically, we found that Nur77 increased GCH1 mRNA stability by inhibiting the expression of microRNA-133a, while Nur77 upregulated SOD1 expression through directly binding to the human SOD1 promoter in vascular endothelial cells. CONCLUSION: Our results suggest that Nur77 plays an essential role in attenuating endothelial dysfunction through activating NO production and anti-oxidant pathways in vascular endothelium. Targeted activation of Nur77 may provide a novel therapeutic approach for the treatment of cardiovascular diseases associated with endothelial dysfunction.

Black Soybean Seed Coat Extract Improves Endothelial Function and Upregulates Oxidative Stress Marker Expression in Healthy Volunteers by Stimulating Nitric Oxide Production in Endothelial Cells.

Black soybean seed coat extract (BE) contains multiple bioactive polyphenols, including flavan-3-ols and anthocyanins. BE improves endothelial function; however, it is unclear whether BE protects endothelial cells from senescence. In this study, we examined the effects of BE on endothelial cell senescence and vascular function in healthy individuals. High concentrations of glucose were used to induce senescence in bovine aortic endothelial cells incubated with BE. Senescence, vascular function, and oxidative stress markers were measured. Incubation with BE remarkably inhibited senescence-associated ß-galactosidase and lactate dehydrogenase activities and dose dependently reduced intracellular reactive oxygen species levels in bovine aortic endothelial cells. BE treatment increased the levels of endothelial nitric oxide synthase (eNOS) mRNA and endothelial nitric oxide (NO) metabolites and increased the mRNA expression of klotho, a gene associated with an antiaging phenotype. To examine the effects of BE in humans, we conducted a clinical study using the second derivative of the fingertip photoplethysmogram to investigate vascular function and aging in 24 healthy volunteers. The participants consumed BE supplements (100 mg/day) or a placebo for 2 weeks. When compared with the placebo group, the BE group showed considerably improved vascular function, NO metabolite levels, and oxidative stress. These results suggest that BE supplementation improves endothelial function, possibly through antioxidant activity and NO production, and may consequently reduce the cardiovascular risk associated with aging. BE supplementation may be an effective and safe approach to reduce the risk of atherosclerosis and cardiovascular disease; however, additional studies investigating chronic vascular inflammation are needed.

Leiomyoma and the importance of genetic variation on genes related to the vasculature system - CßS, MTHFR, NOS3, CYBA, and ACE1.

OBJECTIVE: The link between the systemic vasculature system and tumor biology is here investigated by studying the contribution of CßS (844ins68), MTHFR (677C > T), NOS3 (4a/4b), CYBA (C242T), and ACE1 (I/D) genes to leiomyoma onset, uterus and leiomyoma volumes. METHODS: DNA samples from 130 women with leiomyomas and 527 from healthy women were genotyped by PCR or PCR-RFLP. Qui-square (χ2) or Fisher's exact test were used to test associations. All the mentioned tests were performed in IBM® SPSS® Statistics Version 28. Statistical significance was defined as a p-value < 0.05. RESULTS: Results revealed that CßS (in the codominant and allelic models, p = 0.044 and, p = 0.015, OR = 1.791 [1.114-2.879], respectively), MTHFR (in the codominant, allelic and dominant models, p = 0.009, p = 0.002, OR = 0.585 [0.416-0.824] and p = 0.003, OR = 0.527 [0.346-0.802], respectively) and ACE1 (dominant model, p = 0.045, OR = 0.639 [0.411-0.992]) genes are associated with leiomyoma onset. NOS3 4a4a genotype is associated with a lower uterus volume (p = 0.004). This study also uncovers intriguing epistatic interactions among some genes that further accentuate their roles in disease modulation. Indeed, the epistatic interactions between the CC genotype (MTHFR) and (+/+) (CßS; p = 0.003), 4b4b (NOS3; p = 0.006, OR = 2.050 [1.223-3.439]) or DD (ACE1; p < 0.001, OR = 2.362 [1.438-3.880]) were shown to be associated with the disease, while 4a presence (NOS3) in epistasis with I presence (ACE1), increased the effect protection having just the I allele presence (p = 0.029, OR = 0.446 [0.214-0.930]). CONCLUSIONS: We conclude that variation in genes related to the systemic vascular system can play a role in the onset and development of leiomyoma.

SUMOylation and coupling of eNOS mediated by PIAS1 contribute to maintenance of vascular homeostasis.

Endothelial dysfunction (ED) is commonly considered a crucial initiating step in the pathogenesis of numerous cardiovascular diseases. The coupling of endothelial nitric oxide synthase (eNOS) is important in maintaining normal endothelial functions. However, it still remains elusive whether and how eNOS SUMOylation affects the eNOS coupling. In the study, we investigate the roles and possible action mechanisms of protein inhibitor of activated STAT 1 (PIAS1) in ED. Human umbilical vein endothelial cells (HUVECs) treated with palmitate acid (PA) in vitro and ApoE-/- mice fed with high-fat diet (HFD) in vivo were constructed as the ED models. Our in vivo data show that PIAS1 alleviates the dysfunction of vascular endothelium by increasing nitric oxide (NO) level, reducing malondialdehyde (MDA) level, and activating the phosphatidylinositol 3-kinase-protein kinase B-endothelial nitric oxide synthase (PI3K-AKT-eNOS) signaling in ApoE-/- mice. Our in vitro data also show that PIAS1 can SUMOylate eNOS under endogenous conditions; moreover, it antagonizes the eNOS uncoupling induced by PA. The findings demonstrate that PIAS1 alleviates the dysfunction of vascular endothelium by promoting the SUMOylation and inhibiting the uncoupling of eNOS, suggesting that PIAS1 would become an early predictor of atherosclerosis and a new potential target of the hyperlipidemia-related cardiovascular diseases.

Association between NOS3 gene polymorphisms and genetic susceptibility to congenital heart Disease: A systematic review and meta-analysis.

BACKGROUND: Endothelial nitric oxide (NO) produced by endothelial Nitric Oxide Synthase (eNOS) can promote the expression of pro-angiogenic cytokines and is favorable for angiogenesis. However, the relationship between NOS3 gene polymorphisms and genetic susceptibility to congenital heart disease (CHD) was still unclear. METHODS: We searched five databases including Pubmed, Cochrane Library, Embase, Web of Science, CNKI, and Wan Fang, to find all studies on NOS3 gene polymorphisms and CHD. Rstudio was used to merge the data included in the study to obtain OR, 95%CI, and forest plots. RESULTS: Five relevant literatures were included, including three sites of NOS3 gene, rs1799983 (G894T), rs2070744 (T-786C), and rs7830 (G10T). Several models including the homozygous model of rs1799983 (G894T) gene polymorphism (TT VS GG: OR = 1.602, 95%CI: 1.098 âˆ¼ 2.337, P = 0.027), rs7830 (G10T) gene polymorphism allele model (A VS C: OR = 1.171, 95%CI: 1.029 âˆ¼ 1.333, P = 0.017), homozygous model (AA VS CC: OR = 1.474, 95%CI: 1.122 âˆ¼ 1.936, P = 0.005) and implicit model (AA VS CC + AC: OR = 1.451, 95%CI: 1.133 âˆ¼ 1.859, P = 0.003) indicated that there was a correlation. The results of the combined analysis of each gene model of rs2070744 (T-786C) gene polymorphism sites were not statistically significant, and their P values were all>0.05. CONCLUSION: rs1799983 (G894T) and rs7830 (G10T) polymorphic sites might play a role in the susceptibility of sporadic congenital heart disease and increase the risk of CHD. Yet, it is still necessary to expand the sample size and conduct more prospective/retrospective studies to confirm whether the rs2070744 (T-786C) polymorphism tended to increase the incidence of CHD.

Differential roles of eNOS in late effects of VEGF-A on hyperpermeability in different types of endothelial cells.

Vascular endothelial growth factor (VEGF)-A induces endothelial hyperpermeability, but the molecular pathways remain incompletely understood. Endothelial nitric oxide synthase (eNOS) regulates acute effects of VEGF-A on permeability of endothelial cells (ECs), but it remains unknown whether and how eNOS regulates late effects of VEGF-A-induced hyperpermeability. Here we show that VEGF-A induces hyperpermeability via eNOS-dependent and eNOS-independent mechanisms at 2 days after VEGF-A stimulation. Silencing of expression of the eNOS gene (NOS3) reduced VEGF-A-induced permeability for dextran (70 kDa) and 766 Da-tracer in human dermal microvascular ECs (HDMVECs), but not in human retinal microvascular ECs (HRECs) and human umbilical vein ECs (HUVECs). However, silencing of NOS3 expression in HRECs increased permeability to dextran, BSA and 766 Da-tracer in the absence of VEGF-A stimulation, suggesting a barrier-protective function of eNOS. We also investigated how silencing of NOS3 expression regulates the expression of permeability-related transcripts, and found that NOS3 silencing downregulates the expression of PLVAP, a molecule associated with trans-endothelial transport via caveolae, in HDMVECs and HUVECs, but not in HRECs. Our findings underscore the complexity of VEGF-A-induced permeability pathways in ECs and the role of eNOS therein, and demonstrate that different pathways are activated depending on the EC phenotype.

Association of endothelial nitric oxide synthase gene variants in pre-eclampsia: an updated systematic review and meta-analysis.

INTRODUCTION: Three common endothelial nitric oxide synthase (eNOS) gene variants are existed such as; G-894T, T-786C, and variable number tandem repeats in intron-4 (VNTR intron-4) which has been proposed to be linked with PE. However, there is still debate regarding the findings. To address this, a review was conducted to assess the potential association of eNOS gene variants at these positions with the risk of PE. METHODS: PubMed, Scopus, Science Direct, Hinari, and African Journal Online databases and Google Scholar search engines were utilized to search studies published in English-language until 30 January 2023. The Joanna Briggs Institute Meta-Analysis instrument was used for data extraction process and the Newcastle-Ottawa Scale was used to appraise the quality of the included studies. Meta-regression analysis was conducted using Stata 14 statistical software. The pooled odds ratios (ORs) of fixed and random effect models were utilized to evaluate the association of eNOS gene polymorphism with the risk of PE at 95% CI. Publication bias was assessed using Egger's test and a funnel plot. RESULTS: The study included 47 observational studies involving 13,795 pregnant women (6216 cases and 7579 controls). Pregnant women carrying TT and CC genotypes of eNOS gene at 894 and 786 positions were found to have a greater probability of developing PE as compared to GG and TT genotypes (OR = 1.54 vs. 1.43 and CI: 1.12 - 2.14 vs.1.02 - 2.00 at 95% CI), respectively. However, a significant association was not observed between aa genotype of eNOS gene in VNTR intron-4 region and risk of PE as compared to bb genotype (OR =1.26, 95% CI: 0.83 - 1.89). The allelic model of eNOS gene at all positions showed nonsignificant association with the risk of PE. CONCLUSIONS: The women having eNOS gene variants at 894 and 786 positions showed a significant association with the risk of PE. Yet, the women having eNOS gene variant at intron-4 region showed nonsignificant association with the risk of PE. Thus, this study suggests that eNOS gene variants may play a role in the development of PE, but large-scale studies are required to inaugurate concrete evidence on the roles of eNOS gene variants in PE pathogenesis.

NOS3 and CTH gene mutations as new molecular markers for detection of lung adenocarcinoma.

Gene mutations can contribute to lung adenocarcinoma (LUAD) development, metastasis, and therapy. This study aims to identify mutations in the endothelial nitric oxide synthase (eNOS or NOS3) and cystathionine γ-lyase (CSE or CTH) genes that are connected to LUAD symptoms. Two gene polymorphisms were identified using Sanger sequencing in 31 LUAD patients' formalin-fixed paraffin-embedded (FFPE) tissues. Epidermal growth factor receptor (EGFR) mutation and programmed death-ligand 1 (PD-L1) expression were examined in 110 LUAD patients using real-time polymerase chain reaction and immunohistochemistry. Mutations in the selected genes were retrieved from the gnomAD database for all cancer types and the Mutagene and COSMIC databases for LUAD patients. The GeneMANIA prediction server was used to predict the interaction between the studied genes. Poorly and moderately differentiated tumours predominated, with pT3 N2 Mx being the most prevalent stage. Polymorphism data showed 189 NOS3 gene mutations and 34 CTH gene mutations. In 110 LUAD patients, 14 (12.73%) were PD-L1 positive and expressed 50% or more protein. Eight (7.27%) samples included EGFR mutations, including two deletions and two point mutations in exon 19, four point mutations in exon 21. In gnomAD, 4012 NOS3 mutations and 1214 CTH mutations are present. In the Mutagene and COSMIC databases, the NOS3 gene had 295 and 93 mutations, whereas the CTH gene had 61 and 36. According to the GeneMANIA prediction server, 10 genes are related to NOS3, eight with CTH, 15 with EGFR, and 5 with PD-L1. This study is the first to identify several previously unknown mutations in LUAD patients' NOS3 and CTH genes, with potential therapeutic implications.

THE ROLE OF HEREDITARY PREDISPOSITION (POLYMORPHIC MARKERS OF GLUTATHIONE-S-TRANSFERASE, CATALASE, ENDOTHELIAL NITROGEN OXIDE SYNTHASE GENES) AND SOME ADVERSE ENVIRONMENTAL FACTORS IN THE DEVELOPMENT OF BRONCHO-OBSTRUCTIVE PATHOLOGY IN CHILDREN LIVING IN RADIOACTIVELY CONTAMINATED AREAS. / РОЛЬ СПАДКОВОЇ СХИЛЬНОСТІ (ПОЛІМОРФНИХ МАРКЕРІВ ГЕНІВ ГЛУТАТІОН-S-ТРАНСФЕРАЗ, КАТАЛАЗИ, ЕНДОТЕЛІАЛЬНОЇ СИНТАЗИ ОКСИДУ АЗОТУ) ТА ДЕЯКИХ НЕСПРИЯТЛИВИХ ЧИННИКІВ ДОВКІЛЛЯ У ВИНИКНЕННІ БРОНХООБСТРУКТИВНОЇ ПАТОЛОГІЇ У ДІТЕЙ, МЕШКАНЦІВ РАДІОАКТИВНО ЗАБРУДНЕНИХ ТЕРИТОРІЙ.

OBJECTIVE: summarizing the results of many years of research by the authors on the influence of gene polymorphisms encoding xenobiotic biotransformation enzymes (GSTТ1, GSTM1, GSTР1), antioxidant protection (С^262Т of the catalase gene), endothelial nitric oxide synthase (4a/4b VNTR polymorphism of the eNOS gene), and some environmental factors on the occurrence of broncho-obstructive disorders and the development of bronchial asthma in children, residents of radioactively contaminated areas. MATERIALS AND METHODS: The examined school-aged children were residents of radioactively RCA who had no clinical signs of respiratory pathology. Deletion polymorphism of catalase gene (CAT C^262T), polymorphism of glutathione-S-transferase gene (GSTТ1, GSTM1, GSTР1) and the polymorphism in the 4th intron (4a/4b) of the eNOS gene were studied in the molecular genetics laboratory of the State Institution «Reference Center for Molecular Diagnostics of Public Health Ministry of Ukraine¼. Molecular genetic studies were performed by polymerase chain reaction. The study of the ventilation lung capacity was carried out by the method of computer spirometry based on the data of the «flow-volume¼ loop analysis. A pharmacological inhalation test with a bronchodilator drug which affects the ß2-adrenergic receptors of the lungs was used to detect early changes in the ventilatory lung capacity - bronchial hyperreactivity. RESULTS AND CONCLUSIONS: One of the leading mechanisms, due to which the implementation of hereditary predisposition to bronchial asthma in children living in radioactively contaminated areas is the polymorphism of certain genes of glutathione-S-transferase, catalase, endothelial nitric oxide synthase. With such polymorphic variants of the GST genes, isoforms of enzymes with reduced activity are produced, which limits their ability to effectively neutralize free radicals, which are formed in excess when free radical oxidation processes are activated due to the constant intake of radionuclides with a long half-life into the body of children. Unfavorable factors that increase the risk of developing broncho-obstructive disorders and the likelihood of their implementation in the form of bronchial asthma in children, residents of radioactively contaminated areas, have been identified. It has been established that among them the leading role is played by hereditary predisposition to this disease. On the part of the child, such negative factors were unfavorable conditions of intrauterine development, the presence of signs of exudative-catarrhal diathesis, manifestations of allergies and frequent respiratory diseases from the first months of life.

Analysis of Mechanisms Underlying the Development of Endothelial Dysfunction and Functional Disorders in Experimental Diabetes Mellitus and Their Pathogenetic Correction.

On the model of alloxan-induced diabetes mellitus in rats, the development of oxidative stress and violation of the NO-producing function of the endothelium and internal organs was established. Structural changes in the vascular endothelium due to increased level of atherogenic LDL preventing access of L-arginine to endothelial NO synthase (eNOS) contribute to the development of endothelial dysfunction, which is paralleled by oxidative modification of L-arginine and the formation of inhibitors of eNOS expression (asymmetric dimethylarginine, L-NAME). These findings are indicative of reduced eNOS expression in experimental diabetes mellitus. Administration of L-arginine and its combination with L-carnitine caused an increase in the production NO metabolites and eNOS expression levels by 2.13 and 3.8 times, respectively. In parallel, improvement in the electrolyte excretory function of the kidneys, an increase in the Na,K-ATPase activity in organ homogenates, and a decrease in organ-specific enzymes in blood plasma were observed, which indicates the effectiveness of the correction of the identified violations. A way to eliminate metabolic and functional disorders with combinations of L-arginine and L-carnitine is pathogenetically substantiated. This methodological approach can be recommended for the prevention of microvascular complications in patients with type 1 diabetes mellitus.

Deletion of adipocyte NOS3 potentiates high-fat diet-induced hypertension and vascular remodelling via chemerin.

AIMS: Obesity is an epidemic that is a critical contributor to hypertension and other cardiovascular diseases. Current paradigms suggest that endothelial nitric oxide synthase (eNOS/NOS3) in the vessel wall is the primary regulator of vascular function and blood pressure. However, recent studies have revealed the presence of eNOS/NOS3 in the adipocytes of white adipose tissues and perivascular adipose tissues (PVATs). The current understanding of the role of adipocyte NOS3 is based mainly on studies using global knockout models. The present study aimed to elucidate the functional significance of adipocyte NOS3 for vascular function and blood pressure control. METHODS AND RESULTS: We generated an adipocyte-specific NOS3 knockout mouse line using adiponectin promoter-specific Cre-induced gene inactivation. Control and adipocyte-specific NOS3 knockout (A-NOS3 KO) mice were fed a high-fat diet (HFD). Despite less weight gain, A-NOS3 KO mice exhibited a significant increase in blood pressure after HFD feeding, associated with exacerbated vascular dysfunction and remodelling. A-NOS3 KO mice also showed increased expression of signature markers of inflammation and hypoxia in the PVATs. Among the differentially expressed adipokines, we have observed an upregulation of a novel adipokine, chemerin, in A-NOS3 KO mice. Chemerin was recently reported to link obesity and vascular dysfunction. Treatment with chemerin neutralizing antibody normalized the expression of remodelling markers in the aorta segments cultured in serum from HFD-fed A-NOS3 KO mice ex vivo. CONCLUSION: These data suggest that NOS3 in adipocytes is vital in maintaining vascular homeostasis; dysfunction of adipocyte NOS3 contributes to obesity-induced vascular remodelling and hypertension.

Endothelial lipid droplets suppress eNOS to link high fat consumption to blood pressure elevation.

Metabolic syndrome, today affecting more than 20% of the US population, is a group of 5 conditions that often coexist and that strongly predispose to cardiovascular disease. How these conditions are linked mechanistically remains unclear, especially two of these: obesity and elevated blood pressure. Here, we show that high fat consumption in mice leads to the accumulation of lipid droplets in endothelial cells throughout the organism and that lipid droplet accumulation in endothelium suppresses endothelial nitric oxide synthase (eNOS), reduces NO production, elevates blood pressure, and accelerates atherosclerosis. Mechanistically, the accumulation of lipid droplets destabilizes eNOS mRNA and activates an endothelial inflammatory signaling cascade that suppresses eNOS and NO production. Pharmacological prevention of lipid droplet formation reverses the suppression of NO production in cell culture and in vivo and blunts blood pressure elevation in response to a high-fat diet. These results highlight lipid droplets as a critical and unappreciated component of endothelial cell biology, explain how lipids increase blood pressure acutely, and provide a mechanistic account for the epidemiological link between obesity and elevated blood pressure.