Effects of butanol fraction of Ziziphus mucronata root ethanol extract on glucose homeostasis, serum insulin and other diabetes-related parameters in a murine model for type 2 diabetes

Context:Ziziphus mucronata Willd (Rhamnaceae) is currently used in Nigerian traditional treatment of diabetes mellitus. However, detailed information on the antidiabetic potential of the plant parts is presently unknown. Objectives: The present study investigated the antidiabetic effects of the butanol fraction of Z. mucronata root (ZMBF) in a type 2 diabetes (T2D) model of rats. Materials and methods: T2D was induced in rats by feeding a 10% fructose solution ad libitum for two weeks followed by an intraperitoneal injection of streptozotocin (40 mg/kg bw) and the animals were orally treated with ZMBF 150 or 300 mg/kg bw for five days a week for four weeks. Food and fluid intake, body weight changes and blood glucose levels were monitored during the experiment while other blood and organ specific diabetes-associated parameters were measured at the end of the experiment. Results: After four-week treatment, significantly (p < 0.05) lower blood glucose (19.24 vs 28.96 mmol/L), improved glucose tolerance ability (21.26 vs 28.56 mmol/L), higher serum insulin (131.37 vs 64.20 pmol/L) and liver glycogen (2.40 vs 1.54 mg/g tissue) were observed in the 300 mg/kg ZMBF ingested group compared with the diabetic control group. However, food and fluid intake, body weight gain, HOMA-β, HOMA-IR, serum fructosamine level, hepatic and renal function tests were not significantly (p > 0.05) affected by the treatment of ZMBF. Conclusion: Results of this study suggest that ZMBF treatment, at 300 mg/kg bw, possess antidiabetic activity, but could not ameliorate some diabetes-related parameters in type 2 diabetic rats.