scholarly journals Hematopoietic Cell–Expressed Endothelial Nitric Oxide Protects the Liver From Insulin Resistance

2020 ◽  
Vol 40 (3) ◽  
pp. 670-681
Author(s):  
Brian P. Dick ◽  
Ryan McMahan ◽  
Taft Knowles ◽  
Lev Becker ◽  
Sina A. Gharib ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Insulin Resistance ◽  
Bone Marrow ◽  
Inflammatory Responses ◽  
Hepatic Insulin Resistance ◽  
Metabolic Homeostasis ◽  
Wild Type ◽  
Bone Marrow Derived Cells ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Objective: Mice genetically deficient in endothelial nitric oxide synthase (Nos3 −/− ) have fasting hyperinsulinemia and hepatic insulin resistance, indicating the importance of Nos3 (nitric oxide synthase) in maintaining metabolic homeostasis. Although the current paradigm holds that these metabolic effects are derived specifically from the expression of Nos3 in the endothelium, it has been established that bone marrow–derived cells also express Nos3. The aim of this study was to investigate whether bone marrow–derived cell Nos3 is important in maintaining metabolic homeostasis. Approach and Results: To test the hypothesis that bone marrow–derived cell Nos3 contributes to metabolic homeostasis, we generated chimeric male mice deficient or competent for Nos3 expression in circulating blood cells. These mice were placed on a low-fat diet for 5 weeks, a time period which is known to induce hepatic insulin resistance in global Nos3-deficient mice but not in wild-type C57Bl/6 mice. Surprisingly, we found that the absence of Nos3 in the bone marrow–derived component is associated with hepatic insulin resistance and that restoration of Nos3 in the bone marrow–derived component in global Nos3-deficient mice is sufficient to restore hepatic insulin sensitivity. Furthermore, we found that overexpression of Nos3 in bone marrow–derived component in wild-type mice attenuates the development of hepatic insulin resistance during high-fat feeding. Finally, compared with wild-type macrophages, the loss of macrophage Nos3 is associated with increased inflammatory responses to lipopolysaccharides and reduced anti-inflammatory responses to IL-4, a macrophage phenotype associated with the development of hepatic and systemic insulin resistance. Conclusions: These results would suggest that the metabolic and hepatic consequences of high-fat feeding are mediated by loss of Nos3/nitric oxide actions in bone marrow–derived cells, not in endothelial cells.

Abstract WP103: Endothelial Nitric Oxide Synthase Regulates White Matter Changes after Stroke

Stroke ◽  
2013 ◽  
Vol 44 (suppl_1) ◽  
Author(s):  
Xu Cui ◽  
Michael Chopp ◽  
Tao Yan ◽  
Ruizhuo Ning ◽  
Cynthia Roberts ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
White Matter ◽  
Nitric Oxide Synthase ◽  
Endothelial Nitric Oxide Synthase ◽  
Wild Type ◽  
White Matter Damage ◽  
White Matter Changes ◽  
Significant Difference ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Background: Stroke induced white matter damage is associated with neurological functional deficits, but the underlying mechanisms are not well understood. Endothelial nitric oxide synthase knockout (eNOS-/-) mice exhibited a higher mortality, more severe neurological functional deficit, and decreased neurogenesis, angiogenesis and arteriogenesis after stroke than wild type mice. There are no reports as to whether eNOS is related to the white matter change post-stroke. Methods: Adult male C57BL/6 WT and eNOS -/- mice were subjected to permanent middle cerebral artery occlusion (MCAo) by a filament and sacrificed 7 days after MCAo. Functional evaluation, infarct volume measurement, and immunostaining for analysis of white matter changes were performed. Results: There is no significant difference in the infarction volume between wild type and eNOS -/- (wild type : 23.09%±3.32%; eNOS-/-: 27.83%±4.92%, p=0.436, n=9/group). However, eNOS -/- mice showed significantly decreased functional outcome tested by the singal pellet reaching test (wild type: 38.46%%±1.43%, eNOS-/-: 27.45%±2.41%, p=0.0017). eNOS -/- mice also exhibited increased white matter damage compared to wild type mice, including decrease: 1. Axonal density stained by Bielshowsky Silver in the ipsilateral striatal bundles (wild type: 22.06%±3.0%, eNOS-/-: 13.32%±2.18%,, p=0.031), and in the contralateral striatal bundles (wild type: 65.35%±3.97%, eNOS-/-: 29.38%±5.84%, p=0.02); 2. Density of phasphorylated neurofilament by SMI31-immunoflureoscent staining (wild type: 24.11%±2.06%, eNOS-/-: 7.90%±1.70%, p=0.009); 3. The number of CNPase-positive oligodendrocytes in the ischemic border (wild type: 52.23±5.10, eNOS-/-: 35.59±5.33, p=0.041); 4. The number of NG2-positive oligodendrocyte progenitors in the ischemic border (wild type: 26.22±2.31, eNOS-/-: 18.38±1.95, p=0.0187). There is no significant difference in the density of Luxol fast blue stained myelin in the ipsilateral striatal bundles between wild type and eNOS -/- mice (wild type: 25.21%±3.64%; eNOS-/-: 21.39%±6.29%, p=0.260). Conclusions: We are the first to report that eNOS not only regulates vascular changes and neurogenesis, but also plays an important role in white matter changes after stroke.

EDHF mediates flow-induced dilation in skeletal muscle arterioles of female eNOS-KO mice

2001 ◽  
Vol 280 (6) ◽  
pp. H2462-H2469 ◽  
Author(s):  
An Huang ◽  
Dong Sun ◽  
Mairead A. Carroll ◽  
Houli Jiang ◽  
Carolyn J. Smith ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Skeletal Muscle ◽  
Endothelial Nitric Oxide Synthase ◽  
Hexanoic Acid ◽  
Gracilis Muscle ◽  
Wild Type ◽  
Basal Release ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide ◽  
Cytochrome P 450

Vasodilation to increases in flow was studied in isolated gracilis muscle arterioles of female endothelial nitric oxide synthase (eNOS)-knockout (KO) and female wild-type (WT) mice. Dilation to flow (0–10 μl/min) was similar in the two groups, yet calculated wall shear stress was significantly greater in arterioles of eNOS-KO than in arterioles of WT mice. Indomethacin, which inhibited flow-induced dilation in vessels of WT mice by ∼40%, did not affect the responses of eNOS-KO mice, whereas miconazole and 6-(2-proparglyoxyphenyl)hexanoic acid (PPOH) abolished the responses. Basal release of epoxyeicosatrienonic acids from arterioles was inhibited by PPOH. Iberiotoxin eliminated flow-induced dilation in arterioles of eNOS-KO mice but had no effect on arterioles of WT mice. In WT mice, neither N ω-nitro-l-arginine methyl ester nor miconazole alone affected flow-induced dilation. Combination of both inhibitors inhibited the responses by ∼50%. 1 H-[1,2,4]oxadiazolo[4,3- a]quinoxalin-1-one (ODQ) alone inhibited flow-induced dilation by ∼49%. ODQ + indomethacin eliminated the responses. Thus, in arterioles of female WT mice, nitric oxide and prostaglandins mediate flow-induced dilation. When eNOS is inhibited, endothelium-derived hyperpolarizing factor substitutes for nitric oxide. In female eNOS-KO mice, metabolites of cytochrome P-450, via activation of large-conductance Ca2+-activated K+ channels of smooth muscle, mediate entirely the arteriolar dilation to flow.

scholarly journals Endothelial Nitric Oxide Synthase Haplotypes Are Associated with Features of Metabolic Syndrome

2007 ◽  
Vol 53 (1) ◽  
pp. 91-97 ◽  
Author(s):  
José L González-Sánchez ◽  
María T Martínez-Larrad ◽  
María E Sáez ◽  
Carina Zabena ◽  
María J Martínez-Calatrava ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Insulin Resistance ◽  
Metabolic Syndrome ◽  
Genetic Variation ◽  
Nitric Oxide Synthase ◽  
Endothelial Nitric Oxide Synthase ◽  
Hdl Cholesterol ◽  
Enos Gene ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Abstract Background: The metabolic syndrome, a cluster of several metabolic disorders, is increasingly being recognized as a risk factor for cardiovascular disease. Endothelium-derived nitric oxide facilitates skeletal muscle glucose uptake, and data from animal models indicate that endothelial nitric oxide synthase (eNOS) gene–null mice present with a phenotype of insulin resistance, hypertension, and hypertriglyceridemia, much like that observed in humans with metabolic syndrome. We used haplotype tagging single nucleotide polymorphisms (htSNPs) to investigate the role of genetic variation in the eNOS gene (NOS3) in metabolic syndrome in humans. Methods: We recruited 738 unrelated persons from a cross-sectional population-based epidemiological survey in the province of Segovia in Central Spain (Castille). Metabolic syndrome was defined according to the recently modified National Cholesterol Education Program Adult Treatment Panel III guidelines. Results: Haplotype analysis showed a statistically significant association between some NOS3 gene variants and features of metabolic syndrome. Relative to the most common haplotype, 121, the haplotype 212 was associated with an increased odds ratio (OR) for metabolic syndrome [OR = 1.81, 95% confidence interval (CI) 1.15–2.84], and for decreased HDL-cholesterol concentrations (OR 1.52, 95% CI 1.01–2.29), and with increased mean values for the homeostasis model assessment of insulin resistance (P = 0.043), and triglycerides (P = 0.026). Conclusions: Our results suggest that genetic variation at the eNOS locus is associated with features of metabolic syndrome, and might represent a new genetic susceptibility component for insulin resistance, hypertriglyceridemia, and low HDL-cholesterol concentrations.

scholarly journals Mesenchymal stem cells promote mesenteric vasodilation through hydrogen sulfide and endothelial nitric oxide

2019 ◽  
Vol 317 (4) ◽  
pp. G441-G446 ◽  
Author(s):  
Jan Te Winkel ◽  
Quincy E. John ◽  
Brian D. Hosfield ◽  
Natalie A. Drucker ◽  
Amitava Das ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Stem Cell ◽  
Hydrogen Sulfide ◽  
Nitric Oxide Synthase ◽  
Endothelial Nitric Oxide Synthase ◽  
Wild Type ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Mesenteric ischemia is a devastating process that can result in intestinal necrosis. Mesenchymal stem cells (MSCs) are becoming a promising treatment modality. We hypothesized that 1) MSCs would promote vasodilation of mesenteric arterioles, 2) hydrogen sulfide (H2S) would be a critical paracrine factor of stem cell-mediated vasodilation, 3) mesenteric vasodilation would be impaired in the absence of endothelial nitric oxide synthase (eNOS) within the host tissue, and 4) MSCs would improve the resistin-to-adiponectin ratio in mesenteric vessels. H2S was measured with a specific fluorophore (7-azido-3-methylcoumarin) in intact MSCs and in cells with the H2S-producing enzyme cystathionine β synthase (CBS) knocked down with siRNA. Mechanical responses of isolated second- and third-order mesenteric arteries (MAs) from wild-type and eNOS knockout (eNOSKO) mice were monitored with pressure myography, after which the vessels were snap frozen and later analyzed for resistin and adiponectin via multiplex beaded assay. Addition of MSCs to the myograph bath significantly increased vasodilation of norepinephrine-precontracted MAs. Knockdown of CBS in MSCs decreased H2S production by MSCs and also decreased MSC-initiated MA dilation. MSC-initiated vasodilation was further reduced in eNOSKO vessels. The MA resistin-to-adiponectin ratio was higher in eNOSKO vessels compared with wild-type. These results show that MSC treatment promotes dilation of MAs by an H2S-dependent mechanism. Furthermore, functional eNOS within the host mesenteric bed appears to be essential for maximum stem cell therapeutic benefit, which may be attributable, in part, to modifications in the resistin-to-adiponectin ratio. NEW & NOTEWORTHY Stem cells have been shown to improve survival, mesenteric perfusion, and histological injury scores following intestinal ischemia. These benefits may be due to the paracrine release of hydrogen sulfide. In an ex vivo pressure myography model, we observed that mesenteric arterial dilation improved with stem cell treatment. Hydrogen sulfide release from stem cells and endothelial nitric oxide synthase within the vessels were critical components of optimizing stem cell-mediated mesenteric artery dilation.

scholarly journals Vasodilator mechanisms in the coronary circulation of endothelial nitric oxide synthase-deficient mice

2000 ◽  
Vol 279 (4) ◽  
pp. H1906-H1912 ◽  
Author(s):  
Kathryn G. Lamping ◽  
Daniel W. Nuno ◽  
Edward G. Shesely ◽  
Nobuyo Maeda ◽  
Frank M. Faraci
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Coronary Arteries ◽  
Endothelial Nitric Oxide Synthase ◽  
Coronary Circulation ◽  
Wild Type ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide ◽  
Endothelium Dependent Relaxation ◽  
Deficient Mice

Previous studies have demonstrated that responses to endothelium-dependent vasodilators are absent in the aortas from mice deficient in expression of endothelial nitric oxide synthase (eNOS −/− mice), whereas responses in the cerebral microcirculation are preserved. We tested the hypothesis that in the absence of eNOS, other vasodilator pathways compensate to preserve endothelium-dependent relaxation in the coronary circulation. Diameters of isolated, pressurized coronary arteries from eNOS −/−, eNOS heterozygous (+/−), and wild-type mice (eNOS +/+ and C57BL/6J) were measured by video microscopy. ACh (an endothelium-dependent agonist) produced vasodilation in wild-type mice. This response was normal in eNOS +/− mice and was largely preserved in eNOS −/− mice. Responses to nitroprusside were also similar in arteries from eNOS +/+, eNOS +/−, and eNOS −/− mice. Dilation to ACh was inhibited by N G-nitro-l-arginine, an inhibitor of NOS in control and eNOS −/− mice. In contrast, trifluoromethylphenylimidazole, an inhibitor of neuronal NOS (nNOS), decreased ACh-induced dilation in arteries from eNOS-deficient mice but had no effect on responses in wild-type mice. Indomethacin, an inhibitor of cyclooxygenase, decreased vasodilation to ACh in eNOS-deficient, but not wild-type, mice. Thus, in the absence of eNOS, dilation of coronary arteries to ACh is preserved by other vasodilator mechanisms.

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