Changes of POMC expression in hypothalamus of miR-21 knockout mice / 中华内分泌代谢杂志

ABSTRACT

Objective:To investigate the changes of proopiomelanocortin(POMC) expression in hypothalamus and corresponding metabolism in miR-21 knockout mice.Methods:miR-21 knockout or wild-type C57BL/6J mice were divided into diabetic group and control group, respectively. Diabetic mice model were forged with high-fat diet and low-dose streptozotocin. The changes of body weight and blood glucose in each group were monitored. By the end of the experiment, mice were sacrificed, and POMC protein expression and STAT3 mRNA expression in hypothalamus were detected.Results:There were no significant differences in body weight and blood glucose levels among all groups at baseline( P>0.05). The differences of body weight and blood glucose levels among various groups were compared at 3, 6, 9 and 12 weeks after the model was established. The results showed that body weight of mice in the diabetes group or miR-21 knockout+ diabetes group was higher than that in the control group at each time point( P<0.05). Moreover, there were significant difference in body weight between diabetes group and miR-21 knockout+ diabetes group at 3 and 12 weeks( P<0.05). The blood glucose levels in diabetes group were significantly higher than those in other groups at each time point( P<0.05). The blood glucose level in miR-21 knockout+ diabetes group was lower than that in diabetes group and higher than control group( P<0.05). POMC protein and STAT3 mRNA levels in diabetes group were significantly lower than those in control group, while those in the miR-21 knockout+ diabetes group were higher than those in the diabetes group. Conclusions:The expression of POMC in hypothalamus of miR-21 knockout mice is higher than that of wild-type diabetic mice. miR-21 knockout can decrease blood glucose level and body weight, and improve energy metabolism of diabetic mice.