The effects of Vigna unguiculata on aortic endothelial cells, endothelial nitric oxide synthase expression, lipid profile, and atherosclerosis in ovariectomized rats

Objective: This study purposed to analyze whether Vigna unguiculata is able to increase endothelial cell number, endothelial nitric oxide synthase (eNOS) expression, and to inhibit atherosclerosis in ovariectomized rats. Methods: After acclimatization for one week, twenty four female virgin rats were divided into four groups (n = 6 for each) including ovariectomized (OVX) and OVX + Vigna unguiculata groups; three doses of V.unguiculata extract were applied: 0.5, 2.5 and 5 mg/kg body weight. The number of aortic endothelial cells was counted histologically. Endothelial NOS expression of aortic endothelial cells was analyzed by immunohistochemistry. Serum lipid profile analysis was performed via standard colorimetric methods. In addition, foam cells analysis in aorta was done using oil red O staining in frozen section tissue specimens. Results: The number of endothelial cells were found to be significantly higher in OVX plus 2.5 and 5 mg/kg V.unguiculata extract applied groups compared with OVX alone (control) group. The expression of aortic eNOS in the OVX + 5 mg/kg V.unguiculata applied group was significantly higher compared with control group. V.unguiculata administration at all doses significantly decreased serum levels of low density lipoprotein and triglyceride in comparison to the control animals; on the other hand, total cholesterol levels significantly reduced with administration of V.unguiculata extract at doses of 2.5 and 5 mg/kg, and high density lipoprotein levels increased at 5 mg/kg. Aortic foam cells were found significantly decreased at all doses of V.unguiculata extract. Conclusion: Vigna unguiculata seem to be a good alternative for increasing endotheliall cell number and eNOS expression in the ovariectomy model used. Besides, V.unguiculata also act as anti-atherosclerotic agent by normalizing serum lipid profiles.