NOS3
Nitric oxide synthase, endothelial (EC 1.14.13.39) (Constitutive NOS) (cNOS) (EC-NOS) (Endothelial NOS) (eNOS) (NOS type III) (NOSIII)
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Clinical studies have established a connection between oxidative stress, aging, and atherogenesis. These factors contribute to senescence and inflammation in the endothelium and significant reductions in endothelium-dependent vasoreactivity in aged patients. Tissue-engineered blood vessels (TEBVs) recapitulate the structure and function of arteries and arterioles in vitro. We developed a TEBV model for vascular senescence and examined the relative influence of endothelial cell and smooth muscle cell senescence on vasoreactivity. Senescence was induced in 2D endothelial cell cultures and TEBVs by exposure to 100 µM H O for one week to model chronic oxidative stress. H O treatment significantly increased senescence in endothelial cells and mural cells, human neonatal dermal fibroblasts (hNDFs), as measured by increased p21 levels and reduced NOS3 expression. Although H O treatment induced senescence in both the endothelial cells (ECs) and hNDFs, the functional effects on the vasculature were endothelium specific. Expression of the leukocyte adhesion molecule vascular cell adhesion molecule 1 (VCAM-1) was increased in the ECs, and endothelium-dependent vasodilation decreased. Vasoconstriction and endothelium-independent vasodilation were preserved despite mural cell senescence. The results suggest that the functional effects of vascular cell senescence are dominated by the endothelium.
Keywords
- endothelial cells
- oxidative stress
- senescence
- tissue-engineered blood vessel
- vascular smooth muscle cells
Hypertension (HT), a common age-related disorder, is an important risk factor for cardiovascular disease. This study aims to identify the prevalence of HT in Portuguese centenarians and evaluate whether gene polymorphisms encoding key molecules in blood pressure (BP) regulation are associated with longevity. There were recruited 253 centenarians (100.26 ± 1.98 years) and 268 control subjects (67.51 ± 3.25 years). Hypertension (ESH/ESC2013 and JNC8) and diabetes (WHO) were evaluate. Genetic polymorphisms of renin-angiotensin-aldosterone system (RAAS) and NOS3 were determined. The prevalence of HT among centenarians was 64.4% and the majority (58.9%) were controlled, differing from control group both on frequency (P < 0.001) and on their control (P < 0.001). We found that HT is a risk factor for not achieving longevity (OR 2.531, 95% CI 1.688-3.793, P < 0.001), the same for diabetes (OR 5.669 95% CI 2.966-10.835, P < 0.001), and male gender (OR 2.196, 95% CI 1.493-3.29, P < 0.001). Hypertension, adjusted for gender and diabetes, was independent risk factor anti-longevity (OR 2.007, 95% CI 1320-3.052, P = 0.001). The ACE_D and NOS3_G alleles were more frequent in centenarians compared to controls (P < 0.001, both cases). ACE_II and NOS3_TT genotypes, adjusted for BP, gender and diabetes, increased risk in 3.748 (95% CI 1.887-7.444) and 2.533 (95% CI 1.483-4.327), respectively, in relation to ACE_DD (P < 0.001) and NOS3_GG (P = 0.001), against longevity. Our findings suggest that the prevalence of hypertension was lower in Portuguese centenarians than in the elderly, reinforcing the importance of better cardiovascular risk profiles to achieve longevity even in the presence of genetic condition.
MeSH Terms
- Aged
- Aged, 80 and over
- Humans
- Hypertension
- Longevity
- Nitric Oxide Synthase Type III
- Polymorphism, Genetic
- Portugal
- Renin-Angiotensin System
- Risk Factors
- Sex Factors
Keywords
- ACE
- Centenarians
- Genetic polymorphism
- Hypertension
- Longevity
- NOS3
White matter (WM) damage following a stroke underlies a majority of the neurological disability that is subsequently observed. Although ischemic injury mechanisms are age-dependent, conserving axonal mitochondria provides consistent post-ischemic protection to young and aging WM. Nitric oxide synthase (NOS) activation is a major cause of oxidative and mitochondrial injury in gray matter during ischemia; therefore, we used a pure WM tract, isolated male mouse optic nerve, to investigate whether NOS inhibition provides post-ischemic functional recovery by preserving mitochondria. We show that pan-NOS inhibition applied before oxygen-glucose deprivation (OGD) promotes functional recovery of young and aging axons and preserves WM cellular architecture. This protection correlates with reduced nitric oxide (NO) generation, restored glutathione production, preserved axonal mitochondria and oligodendrocytes, and preserved ATP levels. Pan-NOS inhibition provided post-ischemic protection to only young axons, whereas selective inhibition of NOS3 conferred post-ischemic protection to both young and aging axons. Concurrently, genetic deletion of NOS3 conferred long-lasting protection to young axons against ischemia. OGD upregulated NOS3 levels in astrocytes, and we show for the first time that inhibition of NOS3 generation in glial cells prevents axonal mitochondrial fission and restores mitochondrial motility to confer protection to axons by preserving Miro-2 levels. Interestingly, NOS1 inhibition exerted post-ischemic protection selectively to aging axons, which feature age-dependent mechanisms of oxidative injury in WM. Our study provides the first evidence that inhibition of glial NOS activity confers long-lasting benefits to WM function and structure and suggests caution in defining the role of NO in cerebral ischemia at vascular and cellular levels. White matter (WM) injury during stroke is manifested as the subsequent neurological disability in surviving patients. Aging primarily impacts CNS WM and mechanisms of ischemic WM injury change with age. Nitric oxide is involved in various mitochondrial functions and we propose that inhibition of glia-specific nitric oxide synthase (NOS) isoforms promotes axon function recovery by preserving mitochondrial structure, function, integrity, and motility. Using electrophysiology and three-dimensional electron microscopy, we show that NOS3 inhibition provides a common target to improve young and aging axon function, whereas NOS1 inhibition selectively protects aging axons when applied after injury. This study provides the first evidence that inhibition of glial cell NOS activity confers long-lasting benefits to WM structure and function.
MeSH Terms
- Aging
- Animals
- Brain Ischemia
- Male
- Mice
- Mice, Inbred C57BL
- Mitochondrial Dynamics
- Mitochondrial Proteins
- Nitric Oxide Synthase Type III
- Recovery of Function
- Stroke
- White Matter
- rho GTP-Binding Proteins
Keywords
- Miro-2
- ischemia
- mitochondria
- nitric oxide synthase
- oxidative stress
- white matter
In the vascular system, ageing is accompanied by the accrual of senescent cells and is associated with an increased risk of vascular disease. Endothelial cell (EC) dysfunction is a hallmark of vascular disease and is characterized by decreased angiogenic potential, reduced nitric oxide bioavailability, impaired vasodilation, increased production of ROS, and enhanced inflammation. In ECs, the major producer of nitric oxide is the endothelial nitric oxide synthase (eNOS) enzyme that is encoded by the NOS3 gene. NOS3/eNOS function is tightly regulated at both the transcriptional and post-transcriptional levels to maintain normal vascular function. A key transcriptional regulator of eNOS expression is p53, which has been shown to play a central role in mediating cellular senescence and thereby vascular dysfunction. Herein, we show that, in ECs, the MEOX homeodomain transcription factors decrease the expression of genes involved in angiogenesis, repress eNOS expression at the mRNA and protein levels, and increase the expression of p53. These findings support a role for the MEOX proteins in promoting endothelial dysfunction.
MeSH Terms
- Age Factors
- Aging
- Animals
- Blood Vessels
- Cellular Senescence
- Endothelium, Vascular
- Gene Expression Regulation
- Hemodynamics
- Homeodomain Proteins
- Humans
- Nitric Oxide Synthase Type III
- Signal Transduction
- Sirtuin 1
- Transcription, Genetic
- Tumor Suppressor Protein p53
- Vascular Diseases
Keywords
- MEOX2
- ageing
- cellules endothéliales
- endothelial cells
- nitric oxide synthase
- oxyde nitrique synthase
- p53
- progeria
- progéria
- senescence
- sénescence
- transcription
- vieillissement
Nitric oxide is essential in the vascular adaptation to pregnancy, as knockout mice lacking nitric oxide synthase (NOS3) have abnormal utero-placental perfusion, hypertension and growth restriction. We previously showed with ex vivo studies on transgenic animals lacking NOS3 that adverse intrauterine environment alters fetal programming of vascular reactivity in adult offspring. The current research shows that altered vascular reactivity correlates with higher blood pressure in vivo. Our data suggest that higher blood pressure depends on both genetic background (NOS3 deficiency) and uterine environment, becomes more evident with age (> 7 postnatal weeks), activity and stress, is gender specific (preponderant among males), and can be affected by the sleep-awake cycle. In utero or early postnatal life (< 7 weeks), before onset of hypertension, may represent a potential window for intervention to prevent future cardiovascular disorders. Nitric oxide is involved in the vascular adaptation to pregnancy. Using transgenic animals, we previously showed that adverse intrauterine environment alters vascular reactivity in adult offspring. The aim of our study was to determine if altered vascular programming is associated with abnormal blood pressure (BP) profiles in vivo. Mice lacking a functional endothelial nitric oxide synthase (KO, NOS3 ) and wild-type mice (WT, NOS3 ) were crossbred to generate homozygous NOS3 (KO), maternally derived heterozygous NOS3 (KOM: mother with adverse intrauterine environment from NOS3 deficiency), paternally derived heterozygous NOS3 (KOP: mother with normal in utero milieu) and NOS3 (WT) litters. BP was measured in vivo at 7, 14 and 21 weeks of age. After univariate analysis, multivariate population-averaged linear regression models were used to identify factors affecting BP. When compared to WT offspring, systolic (SBP), diastolic (DBP) and mean (MAP) BP progressively increased from KOP, to KOM, and peaked among KO (P < 0.001), although significance was not reached for KOP. Higher BP was also associated with male gender, older age (> 7 postnatal weeks), higher locomotor activity, daytime recordings, and recent blood pressure transducer insertion (P < 0.001). Post hoc analysis showed that KOM had higher SBP than KOP (P < 0.05). Our study indicates that adverse intrauterine environment contributes, along with multiple other factors, to account for hypertension; moreover, in utero or early postnatal life may represent a possible therapeutic window for prevention of cardiovascular disease later in life.
MeSH Terms
- Animals
- Blood Pressure
- Female
- Fetal Development
- Heart Rate
- Locomotion
- Male
- Mice, Inbred C57BL
- Mice, Transgenic
- Nitric Oxide Synthase Type III
- Telemetry
- Uterus
Keywords
- aging
- fetal programming
- gender differences
- hypertension
- murine animal model
Nitric oxide (NO) triggers multiple signal transduction pathways and contributes to the control of numerous cellular functions. Previous studies have shown in model organisms that the alteration of NO production has important effects on aging and lifespan. We studied in a large sample (763 subjects, age range 19-107 years) the variability of the three human genes (NOS1, -2, -3) coding for the three isoforms of the NADPH-dependent enzymes named NO synthases (NOS) which are responsible of NO synthesis. We have then verified if the variability of these genes is associated with longevity, and with a number of geriatric parameters. We found that gene variation of NOS1 and NOS2 was associated with longevity. In addition NOS1 rs1879417 was also found to be associated with a lower cognitive performance, while NOS2 rs2297518 polymorphism showed to be associated with physical performance. Moreover, SNPs in the NOS1 and NOS3 genes were respectively associated with the presence of depression symptoms and disability, two of the main factors affecting quality of life in older individuals. On the whole, our study shows that genetic variability of NOS genes has an effect on common age related phenotypes and longevity in humans as well as previously reported for model organisms.
MeSH Terms
- Activities of Daily Living
- Adult
- Aged
- Aged, 80 and over
- Aging
- Case-Control Studies
- Cognition
- Depression
- Female
- Geriatric Assessment
- Humans
- Longevity
- Male
- Middle Aged
- Nitric Oxide Synthase Type I
- Nitric Oxide Synthase Type II
- Nitric Oxide Synthase Type III
- Phenotype
- Polymorphism, Single Nucleotide