Gynura procumbens Standardised Extract Reduces Cholesterol Levels and Modulates Oxidative Status in Postmenopausal Rats Fed with Cholesterol Diet Enriched with Repeatedly Heated Palm Oil

Abstract

Gynura procumbens (Lour.) Merr. (GP) has been reported in previous studies to possess antihyperlipidaemic, antioxidative, and cardioprotective properties. This study was aimed to determine the effect of standardised 80% ethanol extract of GP on lipid profiles and oxidative status of hypercholesterolemic rats. Postmenopausal (PM) Sprague-Dawley rats were ovariectomised and fed with 2% cholesterol diet fortified with five times heated palm oil to develop hyperlipidaemia status. Two doses of the extract (250 and 500 mg/kg) and atorvastatin (10 mg/kg) were administered once daily via oral gavage for 24 weeks. Systolic blood pressure (SBP) was increased during the first month in the postmenopausal group and decreased with GP supplementation. Lipid droplets accumulation was shown at the tunica media (TM) area of the aorta in the postmenopausal group and reduced with GP supplementation. Total cholesterol (TC), total triglycerides (TG), low-density lipoprotein (LDL), and malondialdehyde (MDA) levels increased (p<0.05) at 3 and 6 months in the postmenopausal group and were reduced with GP supplementation. GP also increased high-density lipoprotein (HDL) level in the postmenopausal group. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities were reduced in the postmenopausal group compared to control in the sham group but increased (p<0.05) with GP supplementation. The results showed that the higher dose of GP (500 mg/kg) gave better effect. GP has the ability to reduce oxidative stress and prevent membrane cell damage through antioxidant enzyme activity modification and lipid profile changes in postmenopausal rats related to atherosclerosis.