Endoplasmic reticulum stress and unfolded protein response profile in quadriceps of sarcopenic patients with respiratory diseases

Endoplasmic reticulum (ER) stress and an exaggerated unfolded protein response (UPR) were observed in the vastus lateralis (VL) muscle of patients with respiratory sarcopenia and cachexia, particularly in those with lung cancer (LC). The three branches of UPR were similarly upregulated in muscles of cancer cachectic patients, whereas in the sarcopenic chronic obstructive pulmonary disease (COPD) patients, inositol ‐requiring enzyme (IRE) 1 arm was mostly upregulated in their VL. The differential expression profile of ER stress and UPR markers observed in chronic and acute respiratory diseases offers a niche for the design of novel customized therapeutic approaches which may encompass exercise training along with pharmacological strategies purported to boost ER function. AbstractImpaired muscle strength and mass (sarcopenia) are common in patients with respiratory cachexia, namely chronic obstructive pulmonary disease (COPD) and in lung cancer (LC) ‐cachexia. Misfolded/unfolded proteins in endoplasmic reticulum (ER) induce the compensatory unfolded protein response (UPR). Expression of ER stress and UPR markers may be differentially upregulated in vastus lateralis (VL) of patients with respiratory sarcopenia associated with either a chronic condition (COPD) or subacute (LC)‐cachexia. In VL specimens from 40 COPD patients (n = 21, sarcopenic, fat‐free mass index [FFMI] 16 kg/m2 andn = 19, nonsarcopenic, FFMI 18 kg/m2), 13 patients with LC ‐cachexia (FFMI 1...
Source: Journal of Cellular Physiology - Category: Cytology Authors: Tags: ORIGINAL RESEARCH ARTICLE Source Type: research