Hypoglycemic and hepatoprotective effects of d-chiro-inositol-enriched tartary buckwheat extract in high fructose-fed mice

Abstract

This study was designed to investigate the protective effects of D-Chiro-Inositol (DCI) enriched tartary buckwheat extract (DTBE) against high fructose (HF) diet-induced hyperglycemia and liver injury in mice. HPLC analysis revealed that the content of DCI present in purified DTBE was 34.06%. Mice fed 20% fructose in drinking water for 8 weeks significantly displayed hyperglycemia, hyperinsulinemia, dyslipidemia, hepatic steatosis and oxidative stress (p < 0.01). Continuous administration of DTBE in HF-fed mice dose-dependently reduced the HF-induced elevation of body weight, serum glucose, insulin, total cholesterol (TC), total triglycerides (TG) and low density lipoprotein cholesterol (LDL-C) levels, as well as serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), C-reactive protein (CRP) and lactate dehydrogenase (LDH) activities, while the HF-induced decline of serum high density lipoprotein-cholesterol (HDL-C) levels could be markedly elevated in the mice. Meanwhile, DTBE also dose-dependently increased the hepatic total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) activities, and decreased hepatic malonaldehyde (MDA) levels, relative to HF-treated mice. Histopathology of H&E and Oil Red O staining confirmed liver injury induced by a HF diet and the hepatoprotective effect of DTBE. These findings are the first to demonstrate that the intake of DTBE may be a feasible preventive or therapeutic strategy for HF diet-induced hyperglycemia, hepatic steatosis and oxidative injury.