RESUMO
Tobacco smoking is one of the major health problems in the world. This study was conducted to investigate the morphological changes of the dermal elastic tissue of sun-protected skin induced by smoking. Punch biopsies were obtained from the nonexposed skin of 15 smokers and 15 nonsmokers to evaluate the dermal elastic fibers using morphometric analysis and immunohistochemical techniques. Elastic fibers of the reticular dermis were more numerous, thickened and fragmented in smokers than in nonsmokers. Correlations between the cumulative tobacco dose and the morphology of the elastic fibers were highly significant. Immunohistochemical analysis for alpha-1-antitrypsin showed negative cytoplasmic staining for all samples of both smokers and nonsmokers. This study indicates that smoking is one of the risk factors that lead to an increase in elastic fibers of the reticular dermis. This increase is due to elastic tissue degradation rather than by new synthesis, as in solar elastosis. Furthermore, smoking has multiplicative effects on facial ageing and could share, at least in part, a pathophysiological pathway