Anita E M Kneppers1, Ramon C J Langen1, Harry R Gosker1, Lex B Verdijk2, Nanca Cebron Lipovec3, Pieter A Leermakers1, Marco C J M Kelders1, Chiel C de Theije1, Daniel Omersa4, Mitja Lainscak5, Annemie M W J Schols6. 1. Department of Respiratory Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, the Netherlands. 2. Department of Human Biology and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, the Netherlands. 3. Pharmacy Department, University Clinic of Pulmonary and Allergic Diseases Golnik, Golnik, Slovenia. 4. Research Department, National Institute of Public Health, Ljubljana, Slovenia. 5. Department of Cardiology, General Hospital Celje, Celje, Slovenia; Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia. 6. Department of Respiratory Medicine, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, the Netherlands. Electronic address: a.schols@maastrichtuniversity.nl.
Abstract
BACKGROUND: Sarcopenia was recently recognized as an independent condition by an International Classification of Diseases, Tenth Revision, Clinical Modification code, and is a frequently observed comorbidity in chronic obstructive pulmonary disease (COPD). Muscle mass is primarily dictated by the balance between protein degradation and synthesis, but their relative contribution to sarcopenia is unclear. OBJECTIVE: We aimed to assess potential differential molecular regulation of protein degradation and synthesis, as well as myogenesis, in the skeletal muscle of COPD patients with and without sarcopenia. METHODS: Muscle biopsies were obtained from the vastus lateralis muscle. Patients with COPD were clustered based on sarcopenia defined by low appendicular skeletal muscle mass index (nonsarcopenic COPD, n = 53; sarcopenic COPD, n = 39), and compared with healthy nonsarcopenic controls (n = 13). The mRNA and protein expression of regulators and mediators of ubiquitin-proteasome system (UPS), autophagy-lysosome system (autophagy), and protein synthesis were analyzed. Furthermore, mRNA expression of myogenesis markers was assessed. RESULTS: UPS signaling was unaltered, whereas indices of UPS regulation (eg, FOXO1 protein; p-FOXO3/FOXO3), autophagy signaling (eg, LC3BII/I; p-ULK1[Ser757]/ULK1), and protein synthesis signaling (eg, AKT1; p-GSK3B/GSK3B; p-4E-BP1/4E-BP1) were increased in COPD. These alterations were even more pronounced in COPD patients with sarcopenia (eg, FOXO1 protein; p-FOXO1/FOXO1; LC3BII/I; p-ULK(Ser555); p-AKT1/AKT1; AKT1; p-4E-BP1). Furthermore, myogenic signaling (eg, MYOG) was increased in COPD despite a concomitant increase of myostatin (MSTN) mRNA expression, with no difference between sarcopenic and nonsarcopenic COPD patients. CONCLUSION: Together with elevated myogenic signaling, the increase in muscle protein turnover signaling in COPD, which is even more prominent in COPD patients with sarcopenia, reflects molecular alterations associated with muscle repair and remodeling.
BACKGROUND:Sarcopenia was recently recognized as an independent condition by an International Classification of Diseases, Tenth Revision, Clinical Modification code, and is a frequently observed comorbidity in chronic obstructive pulmonary disease (COPD). Muscle mass is primarily dictated by the balance between protein degradation and synthesis, but their relative contribution to sarcopenia is unclear. OBJECTIVE: We aimed to assess potential differential molecular regulation of protein degradation and synthesis, as well as myogenesis, in the skeletal muscle of COPDpatients with and without sarcopenia. METHODS: Muscle biopsies were obtained from the vastus lateralis muscle. Patients with COPD were clustered based on sarcopenia defined by low appendicular skeletal muscle mass index (nonsarcopenic COPD, n = 53; sarcopenic COPD, n = 39), and compared with healthy nonsarcopenic controls (n = 13). The mRNA and protein expression of regulators and mediators of ubiquitin-proteasome system (UPS), autophagy-lysosome system (autophagy), and protein synthesis were analyzed. Furthermore, mRNA expression of myogenesis markers was assessed. RESULTS: UPS signaling was unaltered, whereas indices of UPS regulation (eg, FOXO1 protein; p-FOXO3/FOXO3), autophagy signaling (eg, LC3BII/I; p-ULK1[Ser757]/ULK1), and protein synthesis signaling (eg, AKT1; p-GSK3B/GSK3B; p-4E-BP1/4E-BP1) were increased in COPD. These alterations were even more pronounced in COPDpatients with sarcopenia (eg, FOXO1 protein; p-FOXO1/FOXO1; LC3BII/I; p-ULK(Ser555); p-AKT1/AKT1; AKT1; p-4E-BP1). Furthermore, myogenic signaling (eg, MYOG) was increased in COPD despite a concomitant increase of myostatin (MSTN) mRNA expression, with no difference between sarcopenic and nonsarcopenic COPDpatients. CONCLUSION: Together with elevated myogenic signaling, the increase in muscle protein turnover signaling in COPD, which is even more prominent in COPDpatients with sarcopenia, reflects molecular alterations associated with muscle repair and remodeling.
Authors: Joseph Balnis; Lisa A Drake; Diane V Singer; Catherine E Vincent; Tanner C Korponay; Jeanine D'Armiento; Chun Geun Lee; Jack A Elias; Harold A Singer; Ariel Jaitovich Journal: Am J Respir Cell Mol Biol Date: 2022-06 Impact factor: 7.748
Authors: Judith J M Ceelen; Annemie M W J Schols; Anita E M Kneppers; Roger P H A Rosenbrand; Magda M Drożdż; Stefan J van Hoof; Chiel C de Theije; Marco C J M Kelders; Frank Verhaegen; Ramon C J Langen Journal: Sci Rep Date: 2018-07-17 Impact factor: 4.379
Authors: P A Leermakers; A M W J Schols; A E M Kneppers; M C J M Kelders; C C de Theije; M Lainscak; H R Gosker Journal: Sci Rep Date: 2018-10-09 Impact factor: 4.379