Mulberry leaf powder ameliorate high starch-induced hepatic oxidative stress and inflammation in fish model

Abstract

This study aimed to explore the effects of mulberry leaf powder on glucose metabolism as well as the underlying mechanisms. The largemouth bass (initial body weight: 10.12 ± 0.06 g) were randomly allotted into three treatments, fed low-starch diet (LS, 5%), high-starch diet (HS, 15 %) and high-starch diet with mulberry leaf powder (SM, 50 g/kg diet) for 8 weeks, respectively. Biochemistry parameters were tested using commercial biochemical kits, immune and antioxidant related genes expression were assessed using Q-PCR.The SM group exhibited significantly higher specific growth rate (SGR) and protein efficiency ratio (PER), and lower hepatosomatic index (HSI), liver lipid and glycogen contents than HS treatment. Simultaneously, the suppressed growth accompanied by impaired liver function was found in fish fed the HS diet compared to the LS group. However, supplementation with mulberry leaf diet (SM) significantly reduced plasma glucose, triglyceride (TG) and total cholesterol (TC) contents, the activities of alanine aminotransferase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) compared with the HS group. Accordingly, the liver histological investigation showed an improvement of liver histostructure in the SM group. Furthermore, hepatic SOD and CAT were significantly up-regulated by SM supplementation. Meanwhile, the superoxide dismutase (SOD) and catalase (CAT) activities of SM group were significantly increased, while malondialdehyde (MDA) content significantly reduced in liver compared with the HS group. In addition, SM supplementation significantly down-regulated the expression levels of nf-kb, tnf-a and il-8 in the liver, while il-10 showed significant improvement in the LS group compared to the HS group. Mulberry leaves could alleviate hepatic injuries by regulating inflammation and oxidative stress, providing a theoretical basis for the development of mulberry leaves as a drug against high starch-induced liver disease.