Effects of breaking up prolonged sitting on skeletal muscle gene expression

Breaking up prolonged sitting has been shown to be beneficially associated with cardio-metabolic risk markers in both observational and intervention studies. We aimed to define the acute transcriptional events induced in skeletal muscle by breaks in sedentary time. Overweight/obese adults participated in a randomized three-period, three-treatment cross-over trial in an acute setting (5 hours): seated position with no activity, seated with 2-minute bouts of light- or moderate-intensity treadmill walking every 20 minutes. Vastus lateralis biopsies were obtained in 8 of the 19 participants after each treatment and gene expression examined using microarrays validated with real-time qPCR. Total RNA was extracted from vastus lateralis at the 3 different experimental condition

现有观察性研究与干预性研究均表明，中断长时间久坐行为，与心血管代谢风险标志物存在有益关联。本研究旨在明确久坐时间中断后，骨骼肌中诱导产生的急性转录事件。本研究招募超重/肥胖成年人，开展一项时长5小时的急性环境下随机三周期、三治疗交叉试验，共设置三种干预方式：全程无活动的久坐状态，以及每20分钟进行2分钟轻强度或中等强度跑步机行走的久坐状态。19名受试者中的8名在每项治疗结束后均接受股外侧肌（vastus lateralis）活检；基因表达检测采用经实时定量聚合酶链反应（real-time qPCR）验证的基因芯片（microarrays）技术完成。本研究在三种不同实验条件下，均从股外侧肌中提取总RNA。