Antidiabetic effect of portulaca oleracea extract, alone and plus gliclazide, on streptozotocin-nicotinamide-induced type 2 diabetes in rats

ABSTRACT

Type 2 diabetes is rapidly emerging as a pandemic. To identify an alternative or adjunctive approach to existing medications, the antidiabetic effect of Portulaca oleracea extract [PE], alone and plus gliclazide [Gl], was investigated on streptozotocin [STZ]-nicotinamide-induced type 2 diabetes in rats. Oral administration of the PE, alone and plus Gl, to diabetic rats for 15 and 30 days resulted in a significant decrease in the level of blood glucose, with a concomitant increase in serum insulin level as compared to untreated diabetic rats. The antidiabetic activity was observed to be time-dependent and was most effective in a combined treatment of PE with a reduced dose of Gl. In addition, enzymatic antioxidant superoxide dismutase [SOD] and nonenzymatic antioxidants reduced glutathione [GSH] and vitamin-C were significantly increased after the same periods of treatment except vitamin-C which significantly increased only after 30 days. In conclusion, in type 2 diabetic rats PE shows an antidiabetic action which may be mediated, at least in part, by compensating for defective insulin release and enhancing antioxidant status. The combined therapy of PE plus Gl has better antidiabetic activity than PE individual therapy. Therefore, Portulaca oleracea can be recommended as an adjunctive support for therapy of type 2 diabetes