This Article Full Text Free Full Text (PDF) Free Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to My Personal Article Archive Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Montes de Oca, M. Articles by Tálamo, C. Search for Related Content PubMed PubMed Citation Articles by Montes de Oca, M. Articles by Tálamo, C. Related Content Related Editorial

Peripheral Muscle Alterations in Non-COPD Smokers^*

^* From the Pulmonary Division (Drs. Montes de Oca, Loeb, and Tálamo), Hospital Universitario de Caracas; Instituto de Medicina Experimental (Drs. Torres and Hernández), Sección de Adaptación Muscular; and Instituto de Inmunología (Dr. De Sanctis), Universidad Central de Venezuela, Caracas, Venezuela.

Correspondence to: María Montes de Oca, MD, PhD, Servicio de Neumonología, Piso 8, Hospital Universitario de Caracas, Universidad Central de Venezuela, Los Chaguaramos, Caracas, Venezuela; e-mail: mmdeoca{at}cantv.net

Abstract

Background: Although tobacco smoke is the main cause of COPD, relatively little attention has been paid to its potential damage to skeletal muscle. This article addresses the effect of smoking on skeletal muscle.

Methods: The vastus lateralis muscle was studied in 14 non-COPD smokers (FEV₁/FVC, 78 ± 5%) and 20 healthy control subjects (FEV₁/FVC, 80 ± 3%). Muscular structure, enzyme activity, constitutive and inducible nitric oxide (NO) synthases (endothelial NO oxide synthase [eNOS], neuronal NO synthase [nNOS] and inducible NO synthase [iNOS]), nitrites, nitrates, nitrotyrosine, and the presence of macrophages were analyzed.

Results: In smokers, type I muscle fibers cross-sectional area was decreased, and a similar trend was found in type IIa fibers. Lactate dehydrogenase levels and the percentage of fibers with low oxidative and high glycolytic capacity were increased in smokers. nNOS (96.9 ± 11.7 vs 125.4 ± 31.9 ng/mg protein; p < 0.01) and eNOS (38.9 ± 11.0 vs 45.2 ± 7.7 ng/mg protein [± SD]; p < 0.05) were lower in smokers, while fiber type distribution, capillarity measures, β-hydroxy-acyl-CoA-dehydrogenase levels, iNOS, nitrite, nitrate, and nitrotyrosine levels, and macrophage number in the muscle tissue were similar to the nonsmoker subjects.

Conclusions: Smokers presented some alterations of skeletal muscle such as oxidative fiber atrophy, increased glycolytic capacity, and reduced expression of the constitutive NO synthases (eNOS and nNOS). The findings support some muscular structural and metabolic damage but not the presence of local inflammation in the smokers. In addition, they suggest a possible effect of tobacco smoke impairing the normal process of NO generation.

Key Words: inflammation • nitric oxide • skeletal muscle • smoking

Related Editorial

Cigarette Smoking and the Skeletal Muscles

Peter D. Wagner
Chest 2008 133: 3-4. [Full Text] [PDF]

This article has been cited by other articles:

				R. C. I. Wust, H. Degens, D. A. Jones, M. Montes de Oca, and S. H. Torres Muscle Function in Smokers: Clearing Up the Smoke Chest, July 1, 2008; 134(1): 219 - 220. [Full Text] [PDF]

				P. D. Wagner Cigarette Smoking and the Skeletal Muscles Chest, January 1, 2008; 133(1): 3 - 4. [Full Text] [PDF]