Aryl Hydrocarbon Receptor in Human Dermal Fibroblasts in the Aging Process

The goal of this work was to examine the content of aryl hydrocarbon receptor in human dermal fibroblasts from development until deep aging (from 20 weeks of pregnancy to the age of 85 years) and to determine its role in age-dependent changes in the number of dermal fibroblasts. Aryl hydrocarbon receptor and proliferating cell nuclear antigen (PCNA) were detected with an indirect immunohistochemical technique. The results showed that the portion of fibroblasts with positive staining for aryl hydrocarbon receptor in the dermis gradually increases from 20 weeks of pregnancy to the age of 85 years. The total number and the percentage of PCNA positive fibroblasts in the dermis decreased with the progression of age. The most significant age-dependent reduction in the total and PCNA-positive number of dermal fibroblasts was observed from the antenatal period to the age of 40 years. Correlation analysis showed that both the age-dependent decrease in the number of fibroblasts and the retardation of their proliferation are significantly associated with the age-related increase in the number of dermal fibroblasts positive for aryl hydrocarbon receptor. The results indicate that aryl hydrocarbon receptor is involved in the age-dependent decrease in the number and proliferation of human dermal fibroblasts.