Consumption of herbal medicines in diabetes management is on the increase. The study aimed at investigating effects of ethanol leaf extracts of Tapinanthus globiferus (Family: Loranthaceae) on blood glucose and pancreatic histology in diabetic and normoglycemic rats. Rats were assigned into 7 groups of 5 rats each. Two groups of rats, viz. normal control and diabetic control, did not receive any extract. Test groups were made diabetic with intra-peritoneal injection of alloxan. Two (2) diabetic test groups were administered with 450 and 900mg/kg body weight (bw) of T. globiferus leaf extract, as was also done for 2 normoglycemic test groups. A third diabetic test group was administered with standard antidiabetic metformin (7.14 mg/kg bw). After 14 days, concentrations of blood glucose and histological features were examined in all experimental groups. In diabetic rats given extracts and metformin, blood glucose levels were significantly reduced (p < 0.05) by 68.29 – 83.47 % of initial values; while in normoglycemic rats extracts depreciated glucose concentrations by 19.05 to 21.23 %. Histological studies demonstrated amelioration of degenerative effects on pancreatic islets of diabetic animals, in addition to distortions of pancreatic architecture in normoglycemic animals by high dose extracts. The results suggested glucose-lowering action of extracts, through alterations of pancreatic islet structure / function. Short-term administration of T. globiferus leaves may contribute significantly to normalization of blood glucose by pancreatotrophic effects and can be useful in management of diabetes.
Keywords: Tapinanthus globiferus, mistletoe, leaf, antihyperglycemic, hypoglycemic, pancreatotrophic.