title: [Information exchanges between cells and extracellular                                     matrix. Influence of aging].
abstract: Our interest, since a number of years, has focalized on the worldwide                               rapid expansion of the aging population, accompanied by a progressive                               increase of age-related pathologies. Most of these concern connective                               tissues, that are rich in extracellular matrix (ECM), such as                               osteoarticular, cardiovascular and pulmonary diseases. Therefore                               age-related modifications of connective tissues become of increasing                               importance for the understanding of these diseases. In this article,                               we shall recapitulate some of our (and others') experiments on                               fibronectin, an important matrix glycoprotein mediating cell-matrix                               interactions. We studied the effect of age on fibronectin biosynthesis                               and also the effect of UV-radiation. Both conditions, age and                               radiation, produce a significant increase of fibronectin biosynthesis.                               Some results, when in vitro aging of skin fibroblasts was studied,                               exhibited also a passage-dependent regulation of fibronectin                               biosynthesis. A few studies, quoted in this review, were reported                               about the effect of age on integrin expression and function. An                               important finding was that novel biological fragments of fibronectin                               have proteolytic activities, pro-inflammatory activity in articular                               tissues, enhance malignant transformation as well as other activities.                               Proteolytic activity also increases with age-dependent increase of                               fibronectin fragmentation. This process exhibits positive feedback                               properties, forming a vicious circle, possibly important for the                               age-dependent aggravation of connective tissue diseases. Besides these                               observations, the recent demonstration of fibronectin elasticity                               suggests its implication in novel biological regulation as for                               instance mechano-transduction.
authors: Laboratoire de Recherche Ophtalmologique, Hôtel-Dieu, Université Paris 5, Paris, France. lrobert5@wanadoo.fr
authors: Jacqueline
authors: J
authors: Labat-Robert
mesh_terms: D000375:Aging / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D002450:Cell Communication / Q000235:genetics / Q000502:physiology*; D005109:Extracellular Matrix / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D016326:Extracellular Matrix Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D005353:Fibronectins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D006801:Humans; D016023:Integrins / Q000235:genetics / Q000378:metabolism / Q000502:physiology
chemical_list: D016326:Extracellular Matrix Proteins; D005353:Fibronectins; D016023:Integrins