Determination of the Percentage of Blood Free Leptin Hormone in Diabetic Patients after Treatment with Metformin

Document Type : Original Article


Yazd Diabetes Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran


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.
Materials and Methods
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 metformin 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%±4.2 vs 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.


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