Absence of propolis effect on plasma glycaemic control and lipid metabolism in a diabetic rat model.
Michelle C. Búfalo, Daniela Pacheco Barreiro, Denise R. S. Sartori, and José M. Sforcin
Propolis is a honeybee product that has gained popularity in alternative medicine, due to its biological properties (e.g. immunomodulatory, antimicrobial, antioxidant, anti-inflammatory) and it has been intensely used in health foods. The goal of this work was to analyse the effect of propolis on biochemical parameters in streptozotocin-induced diabetic rats. Animals were kept in metabolic cages and diabetes was induced by a single dose of streptozotocin (40 mg/kg, i.v.). Rats with glycemia higher than 230 mg/ 100 ml were considered as diabetics, and were treated with propolis or with its solvent (ethanol) for 28 days. Glycemia, plasma cholesterol, HDL-cholesterol and triglycerides were determined weekly, as well as the body weight, chow and water intake. Glucose concentration was significantly (p<0.05 ANOVA) elevated in diabetic rats, treated with propolis or ethanol. No statistically significant increase in weight, cholesterol and HDL-cholesterol was seen, and levels of triglycerides were significantly increased only in diabetic rats treated with ethanol. Water and chow intakes were increased in diabetic rats during the experimental period. Data suggests that under these conditions propolis had no effects after the establishment of diabetes. Since the therapeutic potential of propolis has been widely pointed out, further investigation with longer periods of propolis administration as well as with isolated compounds may give some clues for treatment or prevention of diabetes.