Metabolic characteristics of the deltoid muscle in patients with chronic obstructive pulmonary disease

• Published in: The European respiratory journal Vol. 17; no. 5; pp. 939 - 945
• Main Authors: Gea, J.G, Pasto, M, Carmona, M.A, Orozco-Levi, M, Palomeque, J, Broquetas, J
• Format: Journal Article
• Language: English
• Published: Leeds Eur Respiratory Soc 01.05.2001; Maney
• Subjects: Adult; Aged; Biological and medical sciences; Chronic obstructive pulmonary disease, asthma; Citrate (si)-Synthase - metabolism; Creatine Kinase - metabolism; Cross-Sectional Studies; Energy Metabolism - physiology; Exercise Test; Female; Forced Expiratory Volume - physiology; Humans; Isometric Contraction - physiology; L-Lactate Dehydrogenase - metabolism; Male; Medical sciences; Middle Aged; Muscle, Skeletal - physiopathology; Phosphofructokinases - metabolism; Pneumology; Pulmonary Disease, Chronic Obstructive - diagnosis; Pulmonary Disease, Chronic Obstructive - physiopathology; Reference Values; Physical exercise; Human; Lung disease; Physical performance; Pathophysiology; Respiratory disease; Enzyme; Exploration; Deltoid muscle; Metabolism; Chronic; Lung function; Bronchus disease; Exercise tolerance test; Obstructive pulmonary disease
• DOI: 10.1183/09031936.01.17509390
• ISSN: 0903-1936

The purpose of this study was to analyse key enzyme activities of the deltoid muscle (DM) in chronic obstructive pulmonary disease (COPD) patients. The activities of one oxidative enzyme (citrate synthase (CS)), two glycolytic enzymes (lacatate dehydrogenase (LD); and phosphofructokinase (PFK)) and one enzyme related to the use of energy stores (creatine kinase (CK)) were determined in the DM of 10 patients with COPD and nine controls. Exercise capacity (cycloergometry) and the handgrip strength were also evaluated. Although exercise capacity was markedly reduced in COPD (57 +/- 20% predicted), their handgrip strength was relatively preserved (77 +/- 19% pred). The activity of LD was higher in the COPD patients (263.9 +/- 68.2 versus 184.4 +/- 46.5 mmol x min(-1) x g(-1), p<0.01), with a similar trend for CS (67.3 +/- 33.3 versus 46.0 +/- 17.4 mmol x min(-1) x g(-1), p = 0.07). Interestingly, the activity of the latter enzyme was significantly higher than controls if only severe COPD patients were considered (81.8 +/- 31.2 mmol x min(-1) x g(-1), p < 0.01). PFK and CK activities were similar for controls and COPD. Chronic obstructive patients show a preserved or even increased (severe disease) oxidative capacity in their deltoid muscle. This coexists with a greater capacity in the anaerobic part of the glycolysis. These findings are different to those previously observed in muscles of the lower limbs.