The effect of metformin and sea buckthorn (Hippophae rhamnoides L.) in alleviating the symptoms of type 2 diabetes mellitus in the liver of zucker diabetic fatty rats.

Sea buckthorn (Hippophae rhamnoides L.) has many beneficial health properties. In our previous study we showed suppression of hyperglycaemia, water intake, decreased sorbitol levels in the lens of the eyes after sea buckthorn m(Hippophae rhamnoides L.) treatment in Zucker diabetic fatty rats (animal model of type 2 diabetes mellitus, T2DM) with better antioxidant properties of dried berries. Afterwards, we decided to compare the effects of metformin (150 mg/kg b.wt.) and sea buckthorn dried berries (500 or 1000 mg/kg b.wt.) or leaves infusion per os administration on the liver histology in Zucker diabetic fatty (ZDF) rats. Moreover, following biochemical parameters in the blood serum were determined: alanine transaminase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), bilirubin, cholesterol and triglycerides. The histological analyses revealed the appearance of lipid droplets within the liver tissue of diabetic ZDF rats which were not observed in the non-diabetic control animals. Administration of both metformin and sea buckthorn caused a decrease in the number of lipid droplets in the liver. In ZDF rats, an increase in AST, ALP, bilirubin, cholesterol and triglyceride in blood serum was noticed. In comparison with diabetic animals, metformin and sea buckthorn administration did not change the biochemical parameters but only a tendency to reduce some biochemical parameters was noticed. The obtained results suggest that sea buckthorn dried fruits as well as leaves infusion may have biological potential to be used in prevention and treatment of metabolic diseases. Next studies are needed to analyse the exact mechanism of action, develop and promote sea buckthorn berries as a functional food or natural therapeutical products.