Aqueous seed extract of Cola acuminata ameliorated high fat diet-induced hyperlipidaemia in rats

Abstract

Hyperlipidaemia is a medical condition characterized by an elevation of any or all lipid profiles and/or lipoproteins in the blood. It has been well established that nutrition plays a vital role in the aetiology of hyperlipidaemia and cardiovascular diseases. The antihyperlipidaemic potential and toxicological assessment of aqueous seed extract of Cola acuminata in high-fat diet-induced hyperlipidaemic rats were investigated in this study. Twenty-four albino rats were grouped into six of four animals per group. Group 1 (control) was fed formulated feed without high fat. Group 2 was fed a high-fat diet (HFD) but untreated. Group 3 was fed HFD for eight weeks but was treated with atorvastatin from week 5 to week 8 (RFD). Group 4 was fed HFD for eight weeks but was treated with extract 10.71 mg/kg bw from week 5 to week 8. Group 5 was fed HFD for eight weeks but was treated with extract 21.42 mg/kg bw from week 5 to week 8. Group 6 was fed HFD for eight weeks but was treated with extract 42.84 mg/kg bw. The results showed that rats in group 2 (HFD) presented significantly (p<0.05) higher levels of blood lipids, Atherogenic Index (AI) and Coronary Disease (CHD) risk ratio considerably higher than in the healthy control rats (p<0.05). Group 3 (RFD) rats showed significantly (p<0.05) reduced blood lipid profile compared to the HFD but similar to that of the reasonable control. The AI and CHD risk ratios were also not significantly different from that of the control. The ALP, ALT activities of RFD Group, were also not significantly (p<0.05) separate from the control except the AST activity that significantly (p<0.05) increased. The groups treated with 10.71, 21.42 and 42.84 mg/kg bw extract presented reduced serum level of lipids and ALP, ALTand AST activities considerably. AI and CHD risk factors were significantly (p<0.05) decreased, and the reduction was dependent on the dose of the extract. Histopathological assessment of the heart, kidney and liver tissues of the experimental rats presented no significant changes and no sign of acute or chronic injury. However, the HFD group showed with overlying pericardial and coronary artery fat. In the liver, there were mild lymphocytic infiltrations. Therefore, from this study, it is concluded that aqueous extract of Cola acuminata was able to improve HFD-induced hyperlipidaemia and caused no significant damage to the organs (heart, kidney, and liver of the rats).