Etude histologique de l’effet antidiabétique de la propolis -Etude in vivo-

Abstract

Diabetes is a disease characterized by chronic hyperglycemia, which means a very high glucose level in the blood. Traditional medicine offers alternative remedies such as natural products, which today represent an indispensable source for the discovery of new therapeutic molecules, presented for their preventive or curative properties towards various pathologies. In this context, we are interested in the study of propolis extract, a plant resin with numerous therapeutic virtues. The aim of this in vivo study is to evaluate the antidiabetic effect of propolis. Diabetes was induced by a single intraperitoneal injection (IP) of streptozotocin (STZ) at 60 mg/kg for all experimental groups except the control group (T). One week after, rats were treated with two doses of propolis (Tr D1 = 150 mg/kg, Tr D2 = 300 mg/kg) and glibenclamide at 5mg/kg by intragastric gavage for 21 days. Biological parameters were studied throughout the experiment, including weight, water consumption, and blood glucose levels. Histological parameters were also studied after sacrifice. After diabetes induction, a remarkable increase in blood glucose levels was observed in all diabetic rats (D) compared to control rats (T). However, an improvement in blood glucose levels was observed during and after treatment in diabetic rats treated with propolis at 150 mg/kg (Tr D1) and 300 mg/kg (Tr D2) compared to diabetic rats (D). These observations were confirmed by the histological examination of pancreatic tissue in diabetic rats treated with propolis at 150 mg/kg (Tr D1) and 300 mg/kg (Tr D2), revealing almost the same microscopic appearance as in control rats (T). Conversely, diabetic rats demonstrated an irregular aspect with a reduction in the size and number of Langerhans islets. Histological examination of liver tissue showed a similar aspect in all diabetic rats treated with normal hepatocytes and hepatic sinusoids in absence of portal or periportal leukocyte infiltration. The histology of renal tissue in all experimental groups showed normal renal parenchyma. This research shows that the propolis extract presents antidiabetic activity under the conditions of the present study.