The effect of hydroethanolic extract of Morus nigra L. leaves on catalase enzyme activity and histopathology of liver, antioxidant and inflammatory status on type 2 diabetic rats

Abstract

Background: Diabetes mellitus (DM) is associated with increased oxidative stress and pancreatic beta cells damage. The leaf extract of mulberry (Morus nigra L.) contains a variety of phenolic compounds that may be important factors for modulating oxidative stress and inflammation. We evaluated the efficacy of mulberry leaf extract in diabetes management. Methods: Diabetes was induced by high-fat diet and injection of 35mg/kgBW streptozotocin. Wistar rats (n=44) were divided into four groups: healthy control, non-treated, glibenclamidetreated, and extract-treated diabetic rats. The extract-treated group was treated for 4 weeks with mulberry leaf extract. At the end of treatment, liver and blood samples were collected to analysis of biochemical assessments including glycemic factors, inflammatory and oxidative stress parameters and histological evaluation. Results: Blood glucose concentration and insulin resistance were lower (p<0.001) and serum insulin level was higher (0.015) in extract-treated rats compared with non-treated group. MDA level was lower (p=0.057); the activity of the three oxidative stress parameters, TAC, GPx, and SOD, were higher (p=0.026; p=0.001; p<0.001, respectively) and that of catalase was lower in extracttreated group compared with the non-treated rats (p=0.005). Moreover, TNF-α level was lower in extract-treated group (p=0.008). Evaluating the histopathology of liver, we found that the fatty degeneration in extract-treated rats was mild and the cytoplasm of hepatocytes was distended by smaller amount of fatty droplets. Conclusions: This study showed that the mulberry leaf extract improved glycemic response, oxidative stress, inflammation and fatty degeneration in liver cells, suggesting the utility of this herbal remedy in the diabetes management