Role of LOX-1 in vasculogenic erectile dysfunction and effects of resveratrol on LOX-1 and eNOS expression in corpus cavernosum

OBJECTIVEHyperlipidemia causes endothelial dysfunction especially via Ox-LDL. LOX-1 is the main receptor type for the effects of Ox-LDL in endothelial dysfunction. Alterations of cavernosal LOX-1 and eNOS expressions in vasculogenic ED and effects of resveratrol on these two molecules were evaluated in this study.METHODS21 New Zealand white male rabbits were used in this study. Rabbits were seperated into three groups as control, hypercholesterolemia and resveratrol groups with 7 rabbits in each group. Rabbits were fed with normal dietary intake for control group and 2% cholesterol diet for hypercholesterolemia and resveratrol groups through six weeks. Resveratrol 4 mg/kg/day was put in the drinking water of resveratrol group. Plasma cholesterol levels and cavernosal LOX-1 and eNOS expression levels were measured at the end of the study.RESULTSTotal, LDL and HDL cholesterol levels increased significantly in the hypercholesterolemia group when compared with control group (p<0.001). The rise in total and LDL cholesterol levels improved significantly in the resveratrol group (p<0.01) whilst no change in HDL cholesterol levels were observed (p>0.05). There was no difference in LOX-1 mRNA expression levels between three groups (p=0.488). eNOS mRNA expression levels decreased significantly in hypercholesterolemia group when compared with control group (p=0.011). A significant increase for eNOS mRNA expression levels was observed in resveratrol group when compared with hypercholesterolemia group (p<0.001)CONCLUSIONOur study agrees with the previous studies showing that resveratrol improves hypercholesterolemia. We determined for the first time that resveratrol increases eNOS expression in vasculogenic ED. Further studies supporting the beneficial effects of resveratrol in corpus cavernosum are needed to suggest resveratrol use in medical therapy of ED. To our knowledge the present study is the first to show LOX-1 expression in corpus cavernosum and LOX-1 does not seem to play a role in vasculogenic ED.