[Histologic signs of cutaneous aging].

The changes induced by ageing of the skin are particularly visible in photo-exposed areas, indicating the interaction between actinic factors and factors specific to the ageing process itself. The corresponding histological signs affect various structures: epidermis (thinning of the epidermis, reduced cell proliferation...), dermis-epidermis junction (disappearance of the microvilli with defective adhesion of the epidermis to the dermis), dermis (degeneration of elastin and collagen, which is photoinduced, and a moth-eaten appearance with loss of microfibrils as a result of time-related ageing), microcirculation (reduced vascularization, particularly visible in photo-exposed areas...) appendages.