Effects of chromium histidinate on inflammatory markers and brain heat shock proteins in a rat model of type 2 diabetes

Various chromium forms are being regularly used among the western countries as dietary supplement micronutrients. It has been reported that, in type 2 diabetes, organic chromium is capable of improving insulin sensitivity, insulin receptor number, plasma lipids and glucose uptake ability of the cells.In this study effects of chromium histidinate (CrHis), which previously reported was more absorptive by human than the other chromium forms, on plasma glucose and insülin levels with brain tissue malondialdehyde (MDA), glutathione (GSH), tumor necrosis factor-alpha (TNF-?), interleukine-6 (IL?6),heat shock protein 60 (Hsp?60) and heat shock protein 70 (Hsp?70) expressions were researched on high fat fed and experimentally diabetes induced rats. The male Wistar rats (n = 42, 55 days old) were divided into six groups. (i) the group which received a standard diet (12% of calories as fat) was assigned as Control group (C) ; (ii) the group which fed standard diet and concominantly received CrHis (110 mcg CrHis/kg body weight per day) was assigned as C/CrHis group; (iii) the group that received a high-fat diet (HFD; 40% of calories as fat) was determined as HFD group; (iv) the group which received a high-fat diet (HFD; 40% of calories as fat) and concominantly received CrHis (110 mcg CrHis/kg body weight per day) was determined as HFD/CrHis group, (v) the group which fed as HFD but were injected with streptozotocin (STZ) on day 14 (STZ, 40 mg/kg i.p.) was assigned as HFD/STZ group; (vi) the group which fed as HFD and after two weeks injected STZ concominantly supplemented with 110 mcg CrHis/kg body weight per day, was assigned as HFD/STZ/CrHis group. The research finished in 12 weeks. After our analyses; when we checked the effects of our study about insulin levels, C/CrHis and HFD/CrHis groups had higher amounts of insulin levels than the control group and the insulin levels of HFD/STZ/CrHis group was higher than HFD/STZ group (P <0,001). It was observed that, the blood glucose levels in HFD/STZ/CrHis group were significantly lower in comparison to HFD/STZ group (P <0,001). Brain tissue MDA (P <0.0001), TNF- ? (P<0.0001) and IL?6 (P < 0.0001) levels were significantly decreased in HFD and HFD/STZ groups when supplemented with CrHis. Higher brain tissue GSH levels were established in HFD/CrHis and HFD/STZ/CrHis groups than HFD and HFD/STZ groups respectively (P<0.001). It was seen that brain Hsp?60 P < 0.05) and Hsp?70 (P < 0.05) expressions were decreased in HFD and HFD+STZ groups with CrHis application.In conclusion, Cr-Histidinate supplementation positively effected serum insulin and blood glucose levels and ameliorated inflammatory parameters and also stress responses in brain tissues of high fat fed and STZ treated rats.Keywords: Type 2 Diabetes, Chromium Histidinate, High Fat Diet, Streptozotocin, TNF- ? , IL?6, MDA, Gluthathione, HSP