[Ginger accelerates GLUT4 translocation to the cell membrane of C2C12 myotubes]

Backgrounds and Objectives: Diabetes type 2 is a metabolic disorder that affects many organs through chronic high blood levels of glucose. The GLUT4 translocation from cytosolic component to the cell membrane is the most important mechanism and strategy to compensate this situation. At the present study, we aimed to investigate the molecular mechanism of anti-diabetic and hypoglycemic effects of ginger, through evaluating the translocation of GLUT4 in C2C12 myotubes

Material and Methods: In an experimental study, the C2C12 cells were treated with 50microgr/mL concentration of ethyl acetate ginger extract for 3 hours. Sub-cellular fractions were made by centrifugation from homogenized myotubes. After preparation of cytosolic and membrane fractions, the amount of GLUT-4 [an important glucose transporter] was determined using sodium dodecyl sulfate polyacrylamide gel [SDS PAGE] electrophoresis, western blotting and chemiluminescent methods. Finally, gel documents software gene tools were used to analyze subcellular expression of the transporter

Results: The expression of GLUT4 was considerably higher in the ginger-treated cells [112.2 +/- 2.41] compared to the control [the DMSO-treated cells] [98.62 +/- 3.92] [P value < 0.05]. Also, the amount of GLUT4 in membrane fraction of cells treated with ginger extract [100 +/- 0] was higher compared to the DMSO-treated cells [78.46 +/- 5.84]. The amount of GLUT4 in cytosolic fraction of cells treated with ginger extract [12.22 +/- 2.41] was lower compared to the control [the DMSO-treated cells] [20.15 +/- 2.56]. These results show an enhanced translocation of GLUT4 from cytosolic fraction to the cell membrane fraction in the ginger-treatments

Conclusion: One of the mechanisms and also the most important anti-diabetic effects of ginger would be to decrease insulin resistance increasing GLUT4 translocation to the cell membrane, which declines following diabetic complications

Percentage of free to total leptin in diabetic patients and its correlation to blood insulin, glucose and lipids

Leptin is a hormone resulting from the obesity gene which could be important in the pathogenesis of the insulin. Only limited data concerning the interaction of insulin, glucose tolerance and free leptin are available and no data exist on the potential influence of free vs. bound circulating leptin. We, therefore, studied percentage of free to total leptin in diabetic patients. Thirty non-insulin dependent diabetic obese patients [age:50 +/- 20 years, BMI>30 kg/m[2]] and 30 non-insulin dependent diabetic non-obese patients [age:50 +/- 20 years, BMI<25 kg/m[2]] were studied. Free leptin was purified by Gel filtration chromatography and the fractions were collected and then their free leptin was measured by a high sensitive ELISA method. Circulation total leptin and insulin was measured by ELISA. Circulation total leptin was significantly correlated to insulin [P<0.005]. Percentage of free leptin to total in obese subjects was more than non-obese subjects [27% +/- %1 vs.%3 +/- %4, [p<0.001]]. Percentage of free to total leptin showed a positive correlation with insulin [r=0.58 [P<0.001]], insulin resistance [r=31 [P<0.015]] and BMI [r=0.86 [P<0.001]]. The majority of leptin which circulates in obese individuals was free form. Presumably it is bioactive protein of hormone and thus obese subjects are resistant to free leptin

Determination of the percentage of blood free leptin hormone in diabetic patients after treatment with metformin

Plasma leptin exists in protein-bound and free forms, which may affect its hormonal bioactivity. The free and bound forms are changed by the body weight. The purpose of this study was to evaluate the effect of metformin on bound and free plasma leptin concentration. Subjects recruited from Yazd Diabetes Research Centre, Yazd University of Medical Sciences. The participants were new cases of obese type 2 diabetes [BMI > 30 kg/ m2]. Fasting bloods samples, before and after one month treatment with motorman collected. These samples used for the purification of free leptin by HPLC method and analysis of other biochemical parameters. The results indicated that, there was no significant difference observed between the free leptin forms before and after the one month treatment [71% +/- 4.2vs 72 +/- 5]. The one month treatment, reduced blood sugar in patients, but at the same time it did not have a reduction effect on the body weight. Therefore, in the free form of hormone after treatment comparing to before treatment it did not make a significant difference. This confirmed other reports which showed that the variation of free leptin depended on the body weight