Evaluations of the in vitro and in vivo antidiabetic activity of 70 % ethanolic fruit extracts of Rosa abyssinica

Background

Diabetes mellitus is becoming major health challenge with continually increasing burden. High costs of conventional medicines and numerous side effects associated with them, on the other hand, easy availability and accessibility of traditional herbal medicines calls upon experimental investigations to validate their effect on lowering blood glucose level.

Methods

The dried fruit of Rosa abyssinica was macerated with 70 % ethanol and the extract's in vitro antidiabetic activity was investigated using dinitrosalisylic acid method for alpha amylase inhibitory activity. Furthermore, the in vivo hypoglycemic and Antihyperglycemic effects of various doses of the extract (100, 200 and 400 mg/kg) was determined on normoglycemic, glucose loaded (1500 mg/kg) and Streptozotocine (180 mg/kg)-induced diabetic mice models.

Results

The acute oral toxicity study revealed the plant showed no toxic effect on swiss albino mice at 2000 mg/kg. The in vitro alpha amylase inhibitory activity study showed that the extract has comparable IC50 value of 21.37 ± 4.252 μg/ml with the standard drug acarbose (IC50 value of 26.72 ± 3.59 μg/ml). On the other hand, in normal mice, none of the dose levels except at 400 mg/kg significantly reduces blood glucose level. This is in contrast to the oral glucose tolerance test, which the extract produced significant reduction at 60, 90 and 120 min following glucose challenge. The 70 % ethanolic fruit extracts of Rosa abyssinica also experienced profound antidiabetic activity in streptozotocin-induced diabetic model. In the single-dose study, both RAFE200 and RAFE400 demonstrated a significant (P˂0.05) reduction in blood glucose levels at 1, 2, 3, and 4 h. Similarly, in the repeated-dose study, RAFE200 and RAFE400 not only significantly reduced blood glucose levels but also produced a notable improvement in animal body weight.

Conclusion

The 70 % ethanolic fruit extracts of Rosa abyssinica have shown significant in vitro alpha amylase inhibition effect and an in vivo blood glucose level lowering effects in diabetic mice.

Therefore, this study supports the traditional use of Rosa abyssinica in the management of diabetes mellitus.