Studies on the antioxidative and antidiabetic effects of Xylitol and Erythritol in type 2 diabetes: a comparative study.

Abstract

The present study comparatively investigated the antioxidative and antidiabetic effects of xylitol and erythritol using in vitro, ex vivo and in vivo experimental models. The free radical scavenging activities (DPPH, nitric oxide (NO) and ferric reducing power (FRAP) and inhibition of carbohydrate digesting enzymes of the increasing concentrations of xylitol and erythritol (90-720 mM) were determined in vitro. In ex vivo condition, xylitol and erythritol (360-2880 mM) were established for their effects on intestinal glucose absorption and muscle glucose uptake. Additionally, lipid peroxidation (LPO) and reduced glutathione (GSH) concentrations, and the activity of catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR) and glutathione peroxidase (GPx) enzymes were investigated in Fe2+ induced oxidative muscular tissue. Results from these experiments revealed that xylitol exhibited the best activities in terms of all the tested parameters. Xylitol and erythritol were further investigated for their antidiabetic and antioxidative effects in an intervention trial, using a fructose-streptozotocin induced type 2 diabetes rat model. The trial revealed the effects of these sugar alcohols at different concentrations (5%, 10% and 20%), on food and fluid intake, body weight modification, reducing blood glucose level and enhanced glucose tolerance capability. Upon euthanasia of the animals the curative capability on the complications associated with diabetes was determined on serum lipid profile, insulin resistance, pancreatic β-cell function, liver and muscle function. Oxidative stress biomarkers such as LPO, GSH, SOD and CAT were examined in the serum, pancreas, liver and muscle tissues. The in vivo experiment revealed that 10% xylitol dose displayed the most potent antioxidant and antidiabetic properties. Furthermore, data from the in vivo glucose absorption study revealed that xylitol (1 g/kg bw) exhibits better hypoglycemic and antidiabetic effects by delaying gastric emptying.