Nitric Oxide Synthetic Pathway in Red Blood Cells Is Impaired in Coronary Artery Disease

Abstract

BackgroundAll the enzymatic factors/cofactors involved in nitric oxide (NO) metabolism have been recently found in red blood cells. Increased oxidative stress impairs NO bioavailability and has been described in plasma of coronary artery disease (CAD) patients. The aim of the study was to highlight a potential dysfunction of the metabolic profile of NO in red blood cells and in plasma from CAD patients compared with healthy controls.MethodsWe determined L-arginine/NO pathway by liquid-chromatography tandem mass spectrometry and high performance liquid chromatography methods. The ratio of oxidized and reduced forms of glutathione, as index of oxidative stress, was measured by liquid-chromatography tandem mass spectrometry method. NO synthase expression and activity were evaluated by immunofluorescence staining and ex-vivo experiments of L-[15N2]arginine conversion to L-[15N]citrulline respectively.ResultsIncreased amounts of asymmetric and symmetric dimethylarginines were found both in red blood cells and in plasma of CAD patients in respect to controls. Interestingly NO synthase expression and activity were reduced in CAD red blood cells. In contrast, oxidized/reduced glutathione ratio was increased in CAD and was associated to arginase activity.ConclusionOur study analyzed for the first time the whole metabolic pathway of L-arginine/NO, both in red blood cells and in plasma, highlighting an impairment of NO pathway in erythrocytes from CAD patients, associated with decreased NO synthase expression/activity and increased oxidative stress.

Nitric oxide synthetic pathway and cGMP levels are altered in red blood cells from end-stage renal disease patients

“…Venous blood samples (4 ml) from healthy subjects and ESRD patients before hemodialysis were collected as previously described [22]. After blood sample centrifugation at 7009g for 5 min at 4°C, the plasma, buffy coat and top layer of RBCs were removed.…”

“…Notably, RBC-NOS expression and activity are decreased in RBCs from patients with endothelial dysfunction and coronary artery disease [6,22,23]. However, along with the study just mentioned, there are only a few studies concerning NO production, RBC-NOS expression, and activation in RBCs from other pathological conditions [23][24][25].…”

Influence of Simvastatin Chronotherapy on Erythrocytes Nitric oxide Synthase Activity

“…Lipids abnormality increases cholesterol infiltration into the endothelial cells and erythrocytes (Mason et al, 2004;Eligini et al, 2013). In addition to endothelial cells, erythrocytes are involved in transport, metabolism and biosynthesis of NO (Ramirez-Zamora et al, 2013).…”

“…In addition to endothelial cells, erythrocytes are involved in transport, metabolism and biosynthesis of NO (Ramirez-Zamora et al, 2013). Cholesterol enrichment associated with disruption of L-arginine active transport into erythrocytes and endothelial cells, so, the NO production was decreased (Mason et al, 2004;Eligini et al, 2013). Under HC condition, statins persevered structural and functional features of erythrocyte membranes and oxidant/antioxidant balance.…”

“…HC is associated with oxidative stress and endothelial dysfunction, this is attributable to endothelial and erythrocyte cells membrane become cholesterol-enriched (Mason et al, 2004;Eligini et al, 2013). This is resulted in loss of membrane integrity, calcium dysregulation, decreased NO production and increased risks of vascular diseases (Mason et al, 2004;Eligini et al, 2013).…”