Hepatoprotective Effects of Black Pomegranate (Punica granatum L.) Peel Extract on Tert-Butyl Hydroperoxide Induced Oxidative Stress in Rats

Abstract

Background: Black pomegranate (Punica granatum L.) is a native plant of East Asia, which traditionally has been used as a folk medicine to treat many diseases. Objectives: This research investigated the possible protective effects of hydroalcoholic extract of black pomegranate peel extract (BPPE) on oxidative hepatotoxicity induced by tert-butyl-hydroperoxide (t-BHP) in Wistar rats. Methods: The research was carried out on animals randomly assigned to five groups. In the negative control group, 5 mL/kg of normal saline was given orally. In the positive control group, the same amount of normal saline was administered orally for 5 days, and a single dose of t-BHP was injected on the 6th day. In the test groups, 100, 200, and 400 mg/kg of BPPE was administered orally for 5 days, and then rats were injected with a single dose of t-BHP on the 6th day. The rats were euthanized 24 hours after the last injection. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were determined from blood samples. Liver tissue was sampled to measure the level of glutathione (GSH), malondialdehyde (MDA), and catalase (CAT). Hematoxylin and eosin (H & E) staining and histological examination were performed on partial liver samples preserved in 10% formalin. Results: Pretreatment with BPPE at doses of 200 and 400 mg/kg significantly (P < 0.05) reduced ALT, AST, ALP, and MDA levels and increased GSH level and CAT activity. Histopathology examinations revealed that BPPE significantly improved the histological changes in comparison to the positive control group. Conclusions: The results of this research demonstrate the capability of supplemented BPPE to reduce the oxidative hepatotoxicity induced by t-BHP.