Antihypertensive Effects of Apple Peel Extract on Spontaneously Hypertensive Rats

Abstract

Background and Objectives: Apple peel is a rich source of biological active phytochemicals such as flavonoids. The present study investigated the antihypertensive effect of flavonoid-rich Apple Peel Extract (APE) on Spontaneously Hypertensive Rats (SHR). Methodology: Three groups of animals: Control, captopril (20 mg kgG 1 of body weight/day) and APE (25 mg kgG 1 of body weight/day) were fed standard rat chow and their corresponding treatment in sugar-free gelatin, daily for a period of eight weeks. Blood Pressure (BP) was monitored weekly using the tail cuff method. Blood and tissue samples were collected after the eighth week. Results: As expected, treatment with captopril consistently reduced BP (p<0.05). APE treatment reduced both systolic and diastolic BP by 15 and 11 mg Hg, respectively, after 5 weeks of treatment, However, statistical significance was only achieved in systolic BP after eight weeks when compared with control (p<0.05). There were no significant differences in serum and lung ACE activity at week eight. Treatment with APE increased liver superoxide dismutase (SOD) activity by 78% and total reduced Glutathione (GSH) concentrations by 42% when compared to control (p<0.05) but had no effect on the activity of glutathione reductase or peroxidase. Conclusion: Long term intake of APE reduces high blood pressure in SHR possibly through endogenous antioxidant pathways. This preclinical trial suggests that APE as a dietary supplement could be effective in managing early stages of hypertension.