The present study examined the effects of Wasabi leaf (WL) on 45% Kcal high-fat diet (HFD)-fed mild diabetic obese mice. In particular, the hepatoprotective (i.e., liver weight, histopathology of liver, serum aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyltransferase) effects of 12 weeks of continuous oral administration of 250 mg/kg metformin, and 200, 100, or 50 mg/kg WL were investigated. In addition, the hypolipidemic (i.e., serum triglyceride, total cholesterol, high-density lipoprotein-cholesterol, and low-density lipoprotein levels), hypoglycemic (i.e., glycated hemoglobin, blood glucose and insulin levels, pancreatic weight, and immunohistochemical-histopathological analysis of the pancreas), and anti-obesity effects (i.e., body weight, mean food consumption, total and abdominal body fat mass, periovarian fat weight, and histopathology of the periovarian and abdominal wall adipocytes) were monitored. The liver and general antioxidant defense systems were also assessed by lipid metabolism-related gene expression. All diabetes manifestations and related complications, including obesity and non-alcoholic fatty liver disease (NAFLD), were dose-dependently reduced after 84 days of oral treatment with metformin or each of the three dosages of WL. In particular, 50 mg/kg WL showed effective suppression effects against HFD-induced diabetes and related complications of obesity, NAFLD, and hyperlipidemia, comparable to the effects of metformin.
Keywords: Wasabia japonica (miq.) matsum; diabetes; hepatic glucose-regulating enzyme; lipid metabolism-related gene expression; obesity; wasabi leaf/folium.