ANTIOXIDANT AND ANTIHYPERLIPIDEMIC ACTIVITIES OF Ageratum conyzoides LINN AND Portulaca oleracea LINN LEAVES ON FAT INDUCED HYPERLIPIDEMIC RATS

Abstract

The present study was designed to investigate the antioxidant activities and antihyperlipidemic effects of varying levels of inclusion of processed green leafy vegetables (Ageratum conyzoides and Portulaca oleracea leaves) on high fat diet-induced hyperlipidemic rats. Antioxidant assay revealed that the unblanched Portulaca oleracea leaves and Ageratum conyzoides leaves had higher total phenolic and total flavonoid contents, DPPH˙, ABTS˙+, OH˙ and NO˙ radical scavenging activity than the blanched vegetal diets. Seventy-five (75) male Wister rats on the average of 180 ± 20 g were divided into fifteen (15) groups of (5) animals each. They were fed for four weeks on diet specially formulated to contain 5%, 10% and 15% by weight of the leaves of the blanched and unblanched vegetables while the control group was fed with normal rat diet. Lipid profile, liver enzyme markers (alanine aminotransferase: ALT and aspartate aminotransferase: AST), cardiac markers (lactate dehydrogenase: LDH and creatine kinase: CK) and oxidative stress indicators were evaluated. Histology of the heart issues was also evaluated at the end of the study. Serum total cholesterol, triglycerides, low-density lipoprotein and very low-density lipoprotein significantly increased (p<0.0001) in hyperlipidemic control group and were significantly decreased (p<0.0001) at all levels of inclusion of the two vegetal diets (5%, 10% and 15%), and especially 15% inclusion of unblanched Portulaca oleracea. High Density Lipoprotein also increased significantly (p<0.0001) in groups fed with the vegetal diets and in the control diet. ALT and AST activities significantly decreased (p<0.0001) at all levels of inclusion of both blanched and unblanched vegetables and most especially 15% inclusion of unblanched Portulaca oleracea. Also, the activities of CK and LDH which significantly increased (p<0.0001) in hyperlipidemic control group and were significantly decreased (p<0.0001) at all levels of the vegetal diets. In addition, glutathione peroxidase, reduced glutathione, catalase and superoxide dismutase which significantly decreased (p<0.0001) in hyperlipidemic control group were significantly increased (p<0.0001) at all levels of inclusion of the vegetal diets. Inhibitory action against lipid oxidation revealed a significant decrease (p<0.0001). Histological examination showed no pathological lesion at 15% inclusion of the two processed vegetables. These results suggested that incorporation of Portulaca oleracea and Ageratum conyzoides leaves into the diet especially the 15% inclusion of Portulaca oleracea leaves may have therapeutic potentials in the management of hyperlipidemia and the associated complications. Keywords: Portulaca oleracea, Ageratum conyzoides, lipid profile, liver enzyme markers, cardiac enzyme markers, oxidative stress indicators, high-fat diet, hyperlipidemia, histology.