Pharmacological investigations on the role of Trichilia connaroides (Wight. & Arn.) Bentv. on oxidant status and vascular functions in animal models

Abstract

To investigate chloroform (CETC) and methanol (METC) extracts of leaves of Trichilia connaroides (Wight.andArn.) Bentv. for antihyperlipidaemic activity in normal, hypercholesterolemic and hyperhomocysteinemic animals, the possible mechanism of lipid lowering property, antioxidant effect in hypercholesterolemic, hyperhomocysteinemic and diabetic animals and on the secondary complications of diabetes mellitus. A dose of 100mg/kg body weight of extracts was chosen for the study. METHODS Extraction of freshly collected leaves of Trichilia connaroides was carried out by conventional method and chemicals tests were performed to confirm the presence of phytochemicals in the extracts. Test animals were rendered hypercholesterolemic by maintaining them on highfat diet (HFD) in place of normal diet, hyperhomocysteinemic, by oral administration of L-Methionine (1gm / kg) and diabetic by intraperitonial administration of streptozotocin (60mg/kg). Lipid lowering activity of extracts were assessed in normal,hypercholesterolemic and hyperhomocysteinemic animals by measuring the serum triglyceride (TG), total cholesterol (TC) and high density lipoprotein cholesterol (HDL-c). Low density lipoprotein-cholesterol (LDL-c) and very low density lipoprotein-cholesterol (VLDL-c) were calculated. Hypercholesterolemia progression test and hypercholesterolemia regression test were performed to understand the mechanisn of serum cholesterol reduction, and fructose load test and olive oil load test were performed to understand the mechanism of triglyceride reduction. Antioxidant activity of extracts in pro-oxidant state of hypercholesterolemia, hyperhomocysteinemia and diabetic animals were determined by assessing levels of products of lipid peroxidation (LPO) (expressed as MDA), superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GSH) in the heart homogenate of hyperhomocysteinemic and in the liver homogenate of hypercholesterolemic and diabetic animals.