Age-related decrease in the inductability of heat shock protein 72 in normal human skin.

In order to know the effect of chronological ageing on the induction of heat shock protein (HSP) in normal human skin, the 72-kDa HSP (HSP72) was examined in organ-cultured samples of normal human skin which were obtained from 30 individuals (age range 17-86 years). The skin explants were first incubated at 37 degrees C for 24 h, and then heat-treated at 45 degrees C for 1 h. After heat treatment, the skin explants were incubated at 37 degrees C for 1 or 3 h. Immunohistological analysis, using a monoclonal antibody specific for the HSP72, revealed that although the time course of the heat-induced HSP72 expression was similar in the young and aged groups, a lower level of induction of HSP72 was observed in the aged group. This result indicates that there is an age-related dysfunction of the heat shock response in normal human skin.