Department of Human Health and Nutritional Sciences, University of Guelph , Guelph, Ontario , Canada.
Department of Food Science and Human Nutrition, Colorado State University , Fort Collins, Colorado.
Am J Physiol Endocrinol Metab. 2018 Jan 1;314(1):E66-E77. doi: 10.1152/ajpendo.00226.2017. Epub 2017 Oct 3.
Exercise training has robust effects on subcutaneous inguinal white adipose tissue (iWAT), characterized by a shift to a brown adipose tissue (BAT)-like phenotype. Consistent with this, transplantation of exercise-trained iWAT into sedentary rodents activates thermogenesis and improves glucose homeostasis, suggesting that iWAT metabolism may contribute to the beneficial effects of exercise. However, it is yet to be determined if adaptations in iWAT are necessary for the beneficial systemic effects of exercise. To test this, male C57BL/6 mice were provided access to voluntary wheel running (VWR) or remained as a cage control (SED) for 11 nights after iWAT removal via lipectomy (LIPX) or SHAM surgery. We found that SHAM and LIPX mice with access to VWR ran similar distances and had comparable reductions in body mass, increased food intake, and increased respiratory exchange ratio (RER). Further, VWR improved indexes of glucose homeostasis and insulin tolerance in both SHAM and LIPX mice. The lack of effect of LIPX in the response to VWR was not explained by compensatory increases in markers of mitochondrial biogenesis and thermogenesis in skeletal muscle, epididymal white adipose tissue, or interscapular brown adipose tissue. Together, these data demonstrate that mice with and without iWAT have comparable adaptations to VWR, suggesting that iWAT may be dispensable for the metabolic health benefits of exercise.
运动训练对皮下腹股沟白色脂肪组织(iWAT)具有显著影响,表现为向棕色脂肪组织(BAT)样表型的转变。与此一致的是,将经过运动训练的 iWAT 移植到久坐不动的啮齿动物体内会激活产热并改善葡萄糖稳态,这表明 iWAT 代谢可能有助于运动的有益效果。然而,iWAT 的适应性是否是运动有益的全身性影响所必需的,仍有待确定。为了检验这一点,雄性 C57BL/6 小鼠在腹股沟白色脂肪组织(iWAT)切除后(LIPX)或假手术(SHAM),通过腹部脂肪切除术(LIPX)或假手术(SHAM),有或没有选择进行自愿轮跑(VWR)。我们发现,接受 VWR 的 SHAM 和 LIPX 小鼠跑的距离相似,体重减轻、食物摄入增加和呼吸交换率(RER)增加的程度相当。此外,VWR 改善了 SHAM 和 LIPX 小鼠的葡萄糖稳态和胰岛素耐量指标。LIPX 对 VWR 反应缺乏影响,这不能用骨骼肌、附睾白色脂肪组织或肩胛间棕色脂肪组织中线粒体生物发生和产热的标志物代偿性增加来解释。总之,这些数据表明,有和没有 iWAT 的小鼠对 VWR 的适应性相当,这表明 iWAT 可能不是运动代谢健康益处所必需的。