Wong Rochelle, Yuan Li-Yun
Division of Gastrointestinal and Liver Diseases, Keck School of Medicine of University of Southern California, Los Angeles, CA 90033, United States.
World J Hepatol. 2024 Jun 27;16(6):871-877. doi: 10.4254/wjh.v16.i6.871.
Sarcopenia and metabolic dysfunction associated steatotic liver disease (MASLD) are closely intertwined. Sarcopenia, traditionally a disease of the older adult and chronic disease population, has been closely studied as one of the pathophysiologic conditions at play in the development of MASLD. They share similar risk factors of insulin resistance and physical inactivity. Given similar pathophysiology along the liver-muscle axis, sarcopenia has been studied as a risk factor for MASLD, and vice versa. Current research suggests a bidirectional relationship. Given the chronicity of MASLD as a chronic inflammatory liver disease, it can break down muscle mass and lead to sarcopenia, while sarcopenia promotes intramuscular lipid accumulation that releases cytokines that can aggravate inflammation in the liver. However, for the longest time, a lack of consensus definition for MASLD and sarcopenia made it difficult to study their relationship and outcomes. A recent nomenclature update to diagnosing MASLD has made it easier for researchers to identify cohorts for study. However, no gold standard technique to measure muscle mass or consensus sarcopenia definition has been identified yet. Future studies are needed to reach a consensus and reduce diagnostic variation. With similar pathophysiology and shared risk factors between the two diseases, future research may also identify potential therapeutic targets along the liver-muscle axis that would benefit both sarcopenia and MASLD in order to maximize their outcomes.
肌肉减少症与代谢功能障碍相关脂肪性肝病（MASLD）密切相关。肌肉减少症传统上是老年人和慢性病患者群体的疾病，作为MASLD发生发展过程中起作用的病理生理状况之一，已得到深入研究。它们具有相似的胰岛素抵抗和身体活动不足等风险因素。鉴于肝脏 - 肌肉轴上相似的病理生理学，肌肉减少症已被作为MASLD的一个风险因素进行研究，反之亦然。目前的研究表明两者存在双向关系。鉴于MASLD作为一种慢性炎症性肝病的慢性特征，它会分解肌肉量并导致肌肉减少症，而肌肉减少症会促进肌肉内脂质蓄积，释放可加重肝脏炎症的细胞因子。然而，长期以来，由于缺乏对MASLD和肌肉减少症的共识定义，使得研究它们的关系和结果变得困难。最近对MASLD诊断的命名更新使研究人员更容易确定研究队列。然而，尚未确定测量肌肉量的金标准技术或达成共识的肌肉减少症定义。未来需要开展研究以达成共识并减少诊断差异。鉴于这两种疾病具有相似的病理生理学和共同的风险因素，未来的研究还可能确定肝脏 - 肌肉轴上的潜在治疗靶点，这将使肌肉减少症和MASLD都受益，从而实现最佳治疗效果。
