Anti-diabetic activity and safety assessment of Ayurvedic medicine, Jasada bhasma (zinc ash) in rats

Jasada bhasma (zinc ash) is an extensively used Ayurvedic medicine for treating diabetes mellitus. The present communication presents yet unavailable comprehensive scientific data on its physico-chemical nature vis-a-vis anti-diabetic activity and toxicity profile. Zinc ash prepared by traditional method was found to consist of 200-500 nm sized particles, predominantly zinc oxide with hexagonal wurtzite crystal structure. The effective dose range of zinc ash in oral glucose tolerance tests performed using normoglycemic Wistar rats was found to be 3-30 mg/kg. Subsequently anti-diabetic activity was assessed in streptozotocin induced type 1 and type 2 diabetic rats. Four weeks treatment with zinc ash (1, 3, 10 mg/kg) resulted in improved glucose tolerance (16-19%), lowered blood glucose levels (20-33%) and reduced serum insulin levels (27-32%). Systemic absorption was assessed by single dose pharmacokinetic study where serum zinc levels were found to be elevated (3.5 folds) after oral administration of zinc ash. Acute and sub-acute toxicity tests demonstrated safety of zinc ash up to 300 mg/kg doseie. 100 times the efficacy dose in rats. These findings, the first of their kind, provide concrete scientific evidence that justifies usage of zinc ash in diabetes treatment.