Evaluation of anti-hyperlipidemic potential of ethanolic leaf extract of Clerodendrum volubile P. Beauv

Abstract

This study investigated the effect of ethanolic leaf extract of Clerodendrum volubile on lipid profile of hyperlipidemic Wistar rats. The extract was screened and quantified for phytoconstituents according to standard methods. Also, acute and sub-acute toxicity of the extract were carried out on Wistar rats using standard methods. The rats were grouped as follows: General control (group 1) was given distilled water; hyperlipidemic control (group 2), injected intraperitoneally with Poloxamer-407; group 3 rats were administered Atorvastatin (70 mg/kg bwt) orally for 26 days before induction of hyperlipidemia while rats in phytopreventive group (groups 4 and 5) and curative group (groups 7 and 8) were administered sub-lethal doses of 250 and 500mg/kg body weight orally. Hyperlipidemia was induced by single intraperitoneal injection of Poloxamer-407 (1.0 g/kg bwt) in rats within phytopreventive group two hours after 26 days of extract administration while rats in curative group were induced first with Poloxamer-407 two hours on 26th day (feeding with normal diet) before the administration of the extract for two days. All the animals were sacrificed on the 29th day and blood sample was separately collected through cardiac puncture. Antilipidemic activity was measured in the plasma of the rats by estimating the levels of lipidemic markers such as total cholesterol, high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol, very low density lipoprotein (VLDL) cholesterol, and triglycerides to determine the preventive effect and curative effect of the extract. The result revealed that C. volubile ethanolic leaf extract showed the presence of alkaloids, saponins, tannins, flavonoids, steroids and cardiac glycosides. Quantitative analyses of these phytochemicals showed a high concentration of phenolic, followed by flavonoids and alkaloids. A low concentration of saponin was observed while tannin content was the lowest. It was also observed that the levels of total cholesterol, LDL, VLDL cholesterol and triglycerides were significantly lowered in dose dependent manner in both phytopreventive and curative animals, administered 250 and 500 mg/kg body weight, then those animals in the hyperlipidemic control group while HDL level was significantly increased in dose dependent manner. Anti-hyperlipidemic activity was more efficient in C. volubile treated groups as compared to Atorvastatin (standard drug) treated animals. It was evident from this study that C. volubile leaf contained bioactive principles with hypolipidemic effect which were effective as curative agents than prophylactic agents.

Keywords: Clerodendrum volubile, phytochemicals, cardiovascular diseases, plasma lipids, Antihyperlipidemic