BACKGROUND: Age-related changes are easily recognized by examining the skin and lead to important psychological implications, motivating increased scientific interest. OBJECTIVES: This study aimed to analyze, by histomorphometric and autofluorescence approaches, the aged-related alterations in normal human skin. METHODS: Normal abdominal skin samples were taken from eighteen cadavers, including five young subjects (below 20 years old), seven subjects with intermediate age (20-60 years old) and six elderly subjects (over 60 years old). Paraffin-embedded sections were prepared and stained by Hematoxylin and Eosin (H&E) and Van Gieson-elastin trichrome. Afterwards, the H&E specimens were also used for autofluorescence technique. RESULTS: The thickness of elderly epidermis and dermis was reduced compared to middle-aged and young age groups (p<0.05). The elderly and middle-aged groups also showed a marked reduction in the epidermal-dermal contact surface (p<0.05) in comparison to the young group. In addition, we detected a loss of the distribution in the elastic fiber network in the elderly with progressive fragmentation, as demonstrated by Weigert's stain for elastin and poor fluorescent contrast. CONCLUSION: The thickness of the epidermis, dermis, and epidermal-dermal interface contact surface decreased in the aged skin. The changes throughout life in the normal skin did not follow a continuous linear profile, showing drastic alterations especially in the last decades. Autofluorescence approach proved to be an important additional tool for studying the complex relation-ship between the elastic and collagen fibers.
dermis; aging; skin aging; epidermis; skin
