1College of Sport Science, Sungkyunkwan University, Suwon, REPUBLIC OF KOREA; 2College of Engineering, Sangmyung University, Cheonan, REPUBLIC OF KOREA; and 3Division of Humanities and Social Sciences, Pohang University of Science and Technology, Pohang, REPUBLIC OF KOREA.
Med Sci Sports Exerc. 2015 Aug;47(8):1624-34. doi: 10.1249/MSS.0000000000000595.
Training intensity may play a key role in magnifying the protective effect of physical exercise against nonalcoholic fatty liver disease (NAFLD).
This study aimed to test the hypothesis that vigorous-intensity and interval training is as effective as moderate-intensity and continuous exercise training on NAFLD in high-fat diet (HFD)-induced obese mice.
C57BL/6 mice (N = 40) were fed a standard-chow diet (n = 10) or HFD (n = 30) for 16 wk. After the initial 8-wk dietary treatments, HFD mice were further divided into HFD only (n = 10), HFD plus vigorous-intensity and interval treadmill running (VIT) (n = 10), and HFD plus moderate-intensity and continuous treadmill running (MIT) (n = 10) for the remaining 8-wk period.
Chronic exposure to HFD resulted in hepatic steatosis in conjunction with an obese and impaired glucose tolerance condition characterized by dyslipidemia, hyperinsulinemia elevated markers for the liver damage, and hypoadiponectinemia. Although VIT and MIT alleviated the NAFLD conditions, the former was more effective at alleviating hepatic steatosis than the latter. The intensity-dependent benefit of exercise training against hepatic steatosis was associated with greater activation of VIT on hepatic AMP-mediated protein kinase in conjunction with greater suppressive effect of VIT on hypoadiponectinemia, downregulation of the Adiponectin receptor 2 signaling pathway, and upregulation of the NF-κB signaling pathway in the liver.
The current findings suggest that VIT is an alternative way of exercise training to combat hepatic steatosis associated with an obese and impaired glucose tolerance phenotype.
训练强度可能在放大体育锻炼对非酒精性脂肪性肝病（NAFLD）的保护作用方面发挥关键作用。
本研究旨在检验高强度和间歇训练与中等强度和连续运动训练在高脂饮食（HFD）诱导肥胖小鼠的 NAFLD 中同样有效的假设。
将 C57BL/6 小鼠（N=40）分为标准饮食组（n=10）或 HFD 组（n=30），喂养 16 周。在初始 8 周的饮食治疗后，HFD 组小鼠进一步分为 HFD 组（n=10）、HFD 加高强度和间歇跑步机跑步（VIT）组（n=10）和 HFD 加中等强度和连续跑步机跑步（MIT）组（n=10），用于剩余的 8 周。
慢性暴露于 HFD 导致肝脂肪变性，同时伴有肥胖和糖耐量受损，表现为血脂异常、高胰岛素血症、升高的肝损伤标志物和低 adiponectinemia。尽管 VIT 和 MIT 缓解了 NAFLD 状况，但前者比后者更能有效缓解肝脂肪变性。运动训练对肝脂肪变性的强度依赖性益处与 VIT 对肝 AMP 介导的蛋白激酶的更大激活以及 VIT 对低 adiponectinemia 的更大抑制作用、下调 Adiponectin 受体 2 信号通路和上调 NF-κB 信号通路相关联。
目前的研究结果表明，VIT 是一种对抗与肥胖和糖耐量受损表型相关的肝脂肪变性的替代运动训练方式。
