Protective Effect of Pteropyrum scoparium against Heated Palm Olein-Induced Oxidative Stress in Rat Liver

Abstract

Pteropyrum scoparium leaves extract (PSE) is used in traditional medicine for the treatment of different diseases due to its antioxidant properties, yet only a few studies have investigated its protective effect against oxidative stress. This study aimed to asses the biochemical impact of PSE on heated palm olein-induced oxidative stress in rat liver tissue as an experimental model. The palm olein was repeatedly heated at 180 ± 1 °C for 25 hours (5 days' step heating) and then used for rat feeding. The oil properties before and after heating were analyzed by measuring peroxide value (PV), acid value (AV), and total polar compounds (TPC). Forty-eight adult male Fischer 344 rats were divided into four equal groups (n = 12); first group: rats were fed non-heated palm olein (NHPO) diet, second group: rats were fed the same diet as the first group with PSE, third group: rats were fed heated palm olein (HPO) diet, and fourth group: rats were fed the same diet as the third group with PSE. The rats were given PSE by oral gavage (0.1 mg extract/1 mL water/day) for 8 weeks before being sacrificed. Hepatic histopathological changes and biochemical measurements of total antioxidant capacity (TAC) and glutathione (GSH) in liver tissue homogenates were assessed. There was a significant increase in PV, AV, and TPC for HPO as compared to NHPO, P < 0.05. The HPO diet caused oxidative stress in the rat liver, as evidenced by decreasing TAC levels and depletion of GSH. Besides, HPO fed group showed fatty infiltration of the hepatocytes as shown by histopathological analysis, in contrast to the NHPO group that exhibited normal structure and architectures of the hepatic cells. In addition, an improvement was observed in serum biochemical parameters (aspartate aminotransferase and alanine aminotransferase), indicating a protective effect of PSE against HPO-induced liver injuries, confirmed by histopathological studies. In conclusion, PSE supplementation showed a protective effect in HPO fed groups by improving GSH and TAC levels significantly. PSE combats oxidative stress induced by the HPO diet in hepatocytes of experimental rats.