GLYCOSAMINOGLYCANS (GAG) IN THE PATHOGENESIS OF THE FLACCID LUNG SYNDROME: GLYCOSAMINOGLYCANNES ET PATHOGÉNIE DU SYNDROME DE POUMON FLASQUE

The strong male preponderance of patients with the flaccid lung syndrome — without α1-AP deficiency — points to a sex hormone imbalance as a possible factor in the pathogenesis. Such an (inborn) imbalance would profoundly influence the organization of the connective tissue matrix from the beginning, especially at the level of proteoglycans and glycosaminoglycans, at the junctions of the fibrillar components and within the fibrils. Differences in mean molar mass and dispersion of hyaluronic acid from non-emphysematous and emphysematous lungs were found. In vivo effects of sexual steroid hormones in the lungs of mice on the proteoglycan content and composition, as well as on morphological organization of alveolar membranes, are compatible with the hypothesis discussed. The intimate interaction of proteoglycans and glycoproteins with the fibres in the alveolar wall could be visualized. Significant differences in the sex hormone balance were found between individuals with a flaccid lung syndrome and matched controls.