Effect of cocoyam (Colocasia esculenta), unripe plantain (Musa paradisiaca) or their combination on glycated hemoglobin, lipogenic enzymes, and lipid metabolism of streptozotocin-induced diabetic rats

Abstract

Context: The possibility of combining unripe plantain [Musa paradisiacae Linn (Plantaginaceae)] and cocoyam [Colocassia esculenta Linn (Araceae)] in the management of diabetes has not been investigated. Objective: The objective of this study is to evaluate the antihyperglycemic and antihyperlipidemic actions of unripe plantain and cocoyam. Materials and methods: Diabetes was induced in rats by intraperitoneal injection of streptozotocin (STZ) (65 mg/kg body weight). Twelve days after STZ induction, respective groups of diabetic rats were fed cocoyam (810 g/kg), unripe plantain (810 g/kg), and unripe plantain + cocoyam (405:405 g/kg) for 28 d. Body weights, feed intake, biochemical parameters, namely serum glucose, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), atherogenic index, coronary risk index, triacylglycerol, glycated hemoglobin (HbA1C), hepatic isocitrate dehydrogenase, malic enzyme, and glucose-6-phosphate dehydrogenase of the rats and phytochemical composition of the test and standard rat feeds were measured. Results and discussion: Cocoyam or unripe plantain alone significantly (p < 0.05) ameliorated the body weights (18.89 and 19.95% decreases, respectively) and biochemical parameters as compared with those of STZ controls (31.21% decrease). While combination of cocoyam and unripe plantain significantly (p < 0.05) ameliorated the biochemical parameters of the rats (except HbA1C), it did not ameliorate their body weights (28.53% decrease). The feed intake of the experimental rats did not differ from each other (p > 0.05) at the end of experimentation and the feed samples contained considerable amounts of saponins, alkaloids, flavonoids, and tannins. Conclusion: Cocoyam or unripe plantain alone showed better antihyperglycemic and anihyperlipidemic action than their combination.