الفهرس 
Introduction and aim of the workOnly 14 pages are availabe for public view
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Abstract
Diabetes is increasing in the world and causes severe cardiovascular complication, the number one worldwide killer disease. Since they have hind-limbs ischemia with altered neovascularization which leads to foot amputation, then therapeutic strategies are urgently needed. Systemic arterial hypertension is a major risk factor for peripheral vascular disease and growth. The good strategy of treatment will control the symptoms and halt the progression of the disease and substantially lowering the risk of heart attack. In this study we demonstrated the therapeutic effect of mesenchymal stem cells (MSCs) and sodium nitrite (SN) in altered angiogenesis and blood flow of the ischemic hind-limbs in type II diabetes and hypertension respectively. In diabetic study, we found that bone marrow cells from db-/db- mice are altered as evidenced by increased oxidative stress and reduced cell survival marker Akt and adhesion molecules (ICAM1and VCAM1) when compared to control (db-/db+). Femoral artery ligation induced-ischemia was performed in the hind-limbs of db-/db- and db-/db+ mice for 28-days. Enhanced-green-fluorescent-protein (EGFP)-MSCs stimulated with or without exogenous epidermal growth factor (EGF) for 24-hrs were injected locally into the ischemic muscle. Blood flow measured with MoorLDI-Laser and microangiography assessed with X-ray. In this study, the data indicate 100% recovery in db-/db+ compared to 50% recovery in db-/db- mice. Interestingly db-/db- mice had 60% and 96% blood flow recovery and 61% and 98% of vasculogenesis when treated with MSCs alone or MSCs modified with EGF, respectively. Western blot analysis on hind-limbs muscles revealed an increase in endothelial nitric oxide synthase (eNOS) and hypoxia inducible factor (HIF) expression and vascular endothelial growth factor receptor (VEGFR) phosphorylation in db-/db- mice injected with MSCs or MSCs + EGF compared to db-/db- mice. Fluorescent microscopic images illustrate that EGFP-MSCs differentiate into new micro-vessels. Adhesion and migration of MSCs on cultured endothelial cells were ICAM1, VCAM1 and Akt dependent mechanism and elevated when MSCs were pre-stimulated with EGF compared to non-stimulated MSCs. The arterial hypertension is characterized by reduced endogenous nitric oxide (NO) biosynthesis. It has been reported that sodium SN can be converted to NO. Here we studied the potential therapeutic effect of nitrite to treat altered neovascularization in response to ischemia in hypertensive mice. Chronic hypertension was induced by infusion of angiotensin II (Ang-II, 400 ng/Kg) or orally treatment with N (omega)-nitro- L-arginine methyl ester (L-NAME, 0.1g/L). Femoral artery ligation induced-ischemia was performed in the hind-limbs of mice and then treated with or without SN (50 mg/L) for 2 weeks. Sodium nitrite significantly reduced systolic blood pressure in mice receiving Ang II and L-NAME but no effect was observed in sham. Blood flow measured with MoorLDI and microangiography assessed by X-ray displayed 60% recovery in sham compared to 40% recovery in hypertensive mice. Interestingly, sham and hypertensive mice treated with SN displayed a 100% blood flow recovery associated with normalization in capillary density. Cyclic GMP (cGMP) content was significantly enhanced in muscles from mice treated with SN compared to non-treated mice. The nitrite/nitrate ratio was increased in sham and L-NAME groups treated with SN. Immunoprecipitation and Western blot analysis revealed an increase in eNOS, Akt and VEGF receptor phosphorylation in muscles from mice treated with SN compared to non-treated mice.