Molecular Mechanisms and Treatment of Sarcopenia in Liver Disease: A Review of Current Knowledge

Abstract

Sarcopenia is characterized by progressive and generalized loss of skeletal muscle mass and strength that occurs with aging or in association with various diseases. The condition is prevalent worldwide and occurs more frequently in patients with chronic diseases owing to the intrinsic relationship of muscles with glucose, lipid, and protein metabolism. Liver cirrhosis is characterized by the progression of necro-inflammatory liver diseases, which leads to fibrosis, portal hypertension, and a catabolic state, which causes loss of muscle tissue. Sarcopenia is of significant concern in the state of liver cirrhosis because sarcopenia has been associated with higher mortality, increased hospital admissions, worse post-liver transplant outcomes, decreased quality of life, and increased risk for other complications associated with cirrhosis. Therefore, sarcopenia is also an important feature of liver cirrhosis, representing a negative prognostic factor and influencing mortality. An increased understanding of sarcopenia could lead to the development of novel therapeutic approaches that could help improve the cognitive impairment of cirrhotic patients; therefore, we present a review of the mechanisms and diagnosis of sarcopenia in liver disease and existing therapeutic approaches.

Home exercise, branched-chain amino acids, and probiotics improve frailty in cirrhosis: A randomized clinical trial

“…The present study was not designed to elucidate the precise mechanisms involved in the effects of the multifactorial intervention. However, previous studies have reported that exercise improves muscle metabolism and quality, 44 that BCAA stimulates muscle protein synthesis by activating the mammalian target of the rapamycin (mTOR) pathway, 44 and that the multistrain probiotic can improve the proinflammatory state and hyperammonemia, 30 , 45 , 46 both factors favoring muscle wasting. 44 …”

Nutritional Support for Alcoholic Liver Disease

“…In chronic liver disease, glycogen stores in the liver are depleted, and sugar is not available as an energy source, resulting in the breakdown of protein and lipids from muscle and adipose tissue and worsening nutritional status. In addition, the essential branched-chain amino acids (BCAAs) are involved in albumin synthesis and the maintenance of skeletal muscle mass, and thus, a decrease in BCAAs is also closely related to the development of sarcopenia in chronic liver disease [ 49 , 50 ]. Protein metabolism is assessed using serum albumin levels, the BCAA-to-tyrosine ratio (BTR), and albumin–bilirubin score [ 51 ], and their abnormal values are considered an indication for nutritional intervention for PEM.…”

Sarcopenia and non-alcoholic fatty liver disease

“…У больных с ЦП с сопутствующей саркопенией для лечения помимо физических упражнений и L-орнитин-L-аспартата (LOLA) применяются антибиотики, лактулоза, аминокислоты с разветвленной цепью, витамин D, цинк и диета [90]. Основная цель назначения антибиотиков больным с гипераммониемией и ПЭ заключается в подавлении уреазопродуцирующей кишечной микробиоты.…”