Antidiabetic Effects and Mechanisms of Action of Uncaria gambir Roxb. in Diabetic Sprague-Dawley Rats

The antidiabetic properties of Uncaria gambir are not yet fully understood, particularly concerning how it affects diabetic animal models. Further investigation in this aspect is pivotal before initiating clinical evaluations. This study aimed to investigate the antidiabetic activity of U. gambir and how it influences blood glucose levels in diabetic Sprague-Dawley rats. In this study, 28 rats were divided into 7 groups. The groups were as follows: a nondiabetic rat group, a nondiabetic rat group given U. gambir, a diabetic rat group, a diabetic rat group given glibenclamide, and 3 diabetic rat groups given U. gambir at 3 doses (200, 300, and 400 mg/kg). Diabetes was induced using streptozotocin (50 mg/kg) given by intraperitoneal injection. Blood glucose levels were measured weekly, and the animals were euthanized at the end of the experiment. Intracardiac blood and tissues such as the pancreas, liver, and skeletal muscle were collected for further analysis. The results showed that administering U. gambir to diabetic rats resulted in significantly lower blood glucose levels than untreated diabetic rats. U. gambir has a complex mechanism to reduce blood glucose levels. including increase of insulin production, preservation of the islets and pancreatic β cells, and optimization of glycogenesis, as reflected in a significant increase in liver glycogen levels. These findings suggest that U. gambir's multicompound and multitarget capabilities in controlling blood glucose levels may have utility for treatment of diabetes.