Zhang Zheng, Wang Beili, Fei Aihua
Department of Emergency, Xin Hua Hospital affiliated to Shanghai JiaoTong University School of Medicine, Shanghai, China.
Department of Oncology, Xin Hua Hospital affiliated to Shanghai JiaoTong University School of Medicine, Shanghai, China.
Arch Med Sci. 2019 Jan;15(1):214-222. doi: 10.5114/aoms.2018.81037. Epub 2018 Dec 30.
Exercise training is a coadjuvant therapy in preventive cardiology, and it delays cardiac dysfunction and exercise intolerance in heart failure (HF). However, the mechanisms underlying muscle function improvement and cardioprotection are poorly understood. In this study, we tested whether exercise training would counteract skeletal muscle atrophy via activation of the BDNF pathway in myocardial infarction (MI)-induced HF mice.
A cohort of male Sham-operated and MI mice were assigned into 8-week moderate exercise training, and untrained counterparters were used as control. Exercise capacity, plasma norepinephrine (NE) level, heart rate (HR), fractional shortening (FS) and ejection fraction (EF) were measured. The protein expression of BDNF, p-TrkB, p-AMPK and PGC1α were analyzed by Western blot.
Compared with the Sham-operated mice, MI mice displayed reduced total distance run and elevated plasma NE level (both < 0.05). Exercise training significantly improved distance run and plasma NE levels in HF mice (both < 0.05). Significantly increased HR, decreased FS and EF were observed in the MI group as compared to the Sham-operated group, and exercise training prevent the hemodynamic status and systolic dysfunction in MI mice (all < 0.05). The expression of BDNF, p-TrkB, p-AMPK and PGC1α were significantly decreased in the skeletal muscle from MI compared to Sham-operated mice, which were significantly increased by exercise training (all < 0.05). In addition, BDNF siRNA markedly decreased the protein level of p-AMPK and PGC1α in C2C12 myoblasts.
Taken together, our data provide evidence for exercise training may counteract HF-induced muscle atrophy through induced activation of BDNF pathway.
运动训练是预防心脏病学中的一种辅助治疗方法,可延缓心力衰竭(HF)患者的心脏功能障碍和运动不耐受。然而,肌肉功能改善和心脏保护的潜在机制尚不清楚。在本研究中,我们测试了运动训练是否会通过激活脑源性神经营养因子(BDNF)通路来对抗心肌梗死(MI)诱导的HF小鼠的骨骼肌萎缩。
将一组雄性假手术小鼠和MI小鼠进行为期8周的中等强度运动训练,未训练的对照组小鼠作为对照。测量运动能力、血浆去甲肾上腺素(NE)水平、心率(HR)、缩短分数(FS)和射血分数(EF)。通过蛋白质免疫印迹法分析BDNF、磷酸化TrkB(p-TrkB)、磷酸化腺苷酸活化蛋白激酶(p-AMPK)和过氧化物酶体增殖物激活受体γ共激活因子1α(PGC1α)的蛋白表达。
与假手术小鼠相比,MI小鼠的总跑步距离缩短,血浆NE水平升高(均P<0.05)。运动训练显著改善了HF小鼠的跑步距离和血浆NE水平(均P<0.05)。与假手术组相比,MI组的HR显著增加,FS和EF降低,运动训练改善了MI小鼠的血流动力学状态和收缩功能障碍(均P<0.05)。与假手术小鼠相比,MI小鼠骨骼肌中BDNF、p-TrkB、p-AMPK和PGC1α的表达显著降低,运动训练使其显著增加(均P<0.05)。此外,BDNF小干扰RNA(siRNA)显著降低了C2C12成肌细胞中p-AMPK和PGC1α的蛋白水平。
综上所述,我们的数据表明运动训练可能通过诱导BDNF通路的激活来对抗HF诱导的肌肉萎缩。