Heart failure (HF) is the leading cause of death in western countries. Cardiac dysfunction is accompanied by skeletal alterations resulting in muscle weakness and fatigue. Exercise is an accepted interventional approach correcting cardiac and skeletal dysfunction, thereby improving mortality, re-hospitalization and quality of life. Animal models are used to characterize underpinning mechanisms. Transverse aortic constriction (TAC) results in cardiac pressure overload and finally HF. Whether exercise training improves cardiac remodeling and peripheral cachexia in the TAC mouse model was not analyzed yet. In this study, 2 weeks post TAC animals were randomized into two groups either performing a moderate exercise program (five times per week at 60% VO2 max for 40 min for a total of 8 weeks) or staying sedentary. In both TAC groups HF characteristics reduced ejection fraction (− 15% compared to sham, p < 0.001), cardiac remodeling (+ 22.5% cardiomyocyte cross sectional area compared to sham; p < 0.001) and coronary artery congestion (+ 34% diameter compared to sham; p = 0.008) were observed. Unexpectedly, peripheral cachexia was not detected. Furthermore, compared to sedentary group animals from the exercise group showed aggravated HF symptoms [heart area + 9% (p = 0.026), heart circumference + 7% (p = 0.002), right ventricular wall thickness − 30% (p = 0.003)] while muscle parameters were unchanged [Musculus soleus fiber diameter (p = 0.55), Musculus extensor digitorum longus contraction force (p = 0.90)]. The severe TAC model is inappropriate to study moderate exercise effects in HF with respect to cardiac and skeletal muscle improvements. Further, the phenotype induced by different TAC procedures should be well documented and taken into account when planning experiments.

中文翻译：

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小鼠严重 TAC 后心脏和骨骼肌的结构和功能改变：适度运动训练的影响

心力衰竭 (HF) 是西方国家的主要死亡原因。心脏功能障碍伴随着导致肌肉无力和疲劳的骨骼改变。运动是公认的纠正心脏和骨骼功能障碍的介入方法，从而提高死亡率、再住院率和生活质量。动物模型用于表征基础机制。横向主动脉收缩 (TAC) 导致心脏压力超负荷，最终导致 HF。运动训练是否能改善 TAC 小鼠模型中的心脏重塑和外周恶病质尚未分析。在这项研究中，TAC 后 2 周的动物被随机分为两组，要么执行中等运动计划（每周 5 次，最大摄氧量 60%，持续 40 分钟，共 8 周）或久坐不动。在两个 TAC 组中，HF 特征都降低了射血分数（与假手术相比为 - 15%，p < 0.001）、心脏重构（与假手术相比心肌细胞横截面积增加了 + 22.5%；p < 0.001）和冠状动脉充血（与假手术相比，直径增加了 34%假；p = 0.008）被观察到。出乎意料的是，没有检测到外周恶病质。此外，与久坐组动物相比，运动组的动物表现出加重的 HF 症状 [心脏面积 + 9% (p = 0.026)，心脏周长 + 7% (p = 0.002)，右心室壁厚度 - 30% (p = 0.003) ] 而肌肉参数不变 [比目鱼肌纤维直径 (p = 0.55)，趾长伸肌收缩力 (p = 0.90)]。严重 TAC 模型不适用于研究 HF 中的适度运动对心脏和骨骼肌改善的影响。更远，