Endocrine Abstracts

Several epidemiological evidences indicate that consumption of coffee is associated with a lower risk of type 2 diabetes mellitus (T2DM); however, there is dearth of experimental data to support these observations. Given that associations do not necessarily infer causality; the present study investigate the effect of coffee consumption on glucose regulation, T2DM and the probable mechanisms of action, if any, using an animal model. Twenty-four (24) Sprague–Dawley rats weighing between 120 and 150 g were randomly divided into four equal groups of six animals. The rats were given either a normal diet (ND); ND supplemented with coffee (ND+COF); high sucrose-diet (HSD); and HSD supplemented with coffee (HSD+COF). Coffee (300 mg/kg BW) was administered by oral gavage once daily while free access to HSD (30% w/v) as drinking water was provided according to the method of Riberio et al. (2005) and modifying. Treatment lasted for 12 consecutive weeks during which experimental measurements such as fasting blood glucose (FBG), oral glucose tolerance test (OGTT), and insulin tolerance test (ITT) were performed. Serum insulin level, lipid profile and oxidative parameters were also determined in all experimental rats. HSD rats were insulin resistant and had significantly elevated levels of insulin, malondialdehyde (MDA), triglyceride (TG), LDL while HDL level, superoxide dismutase (SOD) and glutathione (GSH) activities were significantly reduced. In contrast, coffee administration significantly up-regulate glucose tolerance, insulin sensitivity, HDL level, SOD, and GSH activities while MDA, TG, and LDL levels were reduced. These findings suggest that coffee consumption attenuates the development of insulin resistance and/or T2DM in HSD-fed rat.