Can physical exercise induce differentiation from myoblasts to brown adipocytes ?

最近，越来越多的证据表明，PRDM16作为一个双向开关，驱动表达myf -5的间充质干细胞向棕色脂肪细胞（BA）的分化。当前研究的目的是测试体育锻炼是否能改变这种差异事件。雄性C57BL/6J小鼠随机分为3组：久坐对照组、急性游泳组和BA功能阳性对照冷暴露组。骨骼肌的几个部分被用来分析可能与这一事件有关的mRNA和蛋白质。BA特异性标志物UCP-1 mRNA仅在各组肩胛间肌中表达。游泳组与对照组相比，PRDM16 mRNA和蛋白水平显著升高。此外，游泳组的PRDM16和PRDM16转换的关键调节因子C/EBP-β水平显著高于对照组。这些结果表明，游泳运动对myf -5表达的成肌细胞向BA的分化事件有强大的影响，从而提示游泳运动作为一种新的抗肥胖治疗方法在临床上有一定的应用价值。

Recently, there has been growing evidence that PRDM16 acts as a bidirectional switch to drive the differentiation of Myf-5-expressing mesenchymal stem cells into the brown adipocytes (BA). The aim of the current study was to test whether physical exercise modifies this differential event. Male C57BL/6J mice were randomly divided into 3 groups: the sedentary control group, the acute swimming group and the cold exposed group, a positive control of BA function. Several partsof skeletal muscles were used for analysis of both mRNA and protein which might be concerned with this event. Expression of mRNA for UCP-1, a specific marker of BA, was detected only in interscapular muscles in each group. Swimming group significantly increased PRDM16 mRNA and protein levels compared with control group. Moreover, levels of PRDM16 and C/EBP-β, which is a pivotal key regulator for switching of PRDM16, were significantly higher in swimming group than in control group. These results demonstrate that swimming exercise has powerful effects on differentiation event of Myf-5-expressed myoblasts into BA, thereby suggesting that swimming exercise is clinically useful as new anti-obesitytreatment.