Published in Cell Metabolism [ March 2005] the study of both University of Michigan and Harvard University suggests that the Leptin has an important role in regulating blood sugar. It does this thing in two different body-pathways:
controling appetite and fat deposit
helping liver to manage the excess of glucose reserves
Doctors already know that disrupted leptin's role of appetite-controlling cause obesity. But the question that has been excited the medical world for years is why some obese patients go developing diabetes while many others no. This new study suggets that a disruption to both pathways is necessary to lead obesity to diabetes.

The lead researcher Martin G Myers, involved only mice in this 6 months study. Part of mices, called s/s strain, did not develop diabetes despite of fact they ate to much and became obese. The other part with leptin dysfunction became obese and died of diabetes.

"The blood sugar of the s/s mice was high, but it was much more in control than mice that had no leptin receptors at all, and was not because of differences in their insulin production. And when the s/s mice were put on calorie-restricted diets, their blood sugar normalized. These findings suggest that since the leptin- STAT3 signal was disrupted, some other signal must have been keeping glucose in check," said Dr. Martin G. Myers.

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