1. Intrinsic versus Extrinsic Aging: A Histopathological, Morphometric and Immunohistochemical Study of Estrogen Receptor β and Androgen Receptor.
- Author
-
Seleit I, Bakry OA, El Repey HS, and Ali R
- Subjects
- Adult, Aged, Epidermis radiation effects, Estrogen Receptor beta analysis, Female, Humans, Male, Middle Aged, Receptors, Androgen analysis, Skin Aging radiation effects, Ultraviolet Rays adverse effects, Young Adult, Epidermis metabolism, Epidermis pathology, Estrogen Receptor beta metabolism, Receptors, Androgen metabolism, Skin Aging pathology, Skin Aging physiology
- Abstract
Skin is a target organ of sex steroids which play important roles in skin health and disease. The aim of this study is to investigate the expression of estrogen receptor β (ERβ) and androgen receptor (AR) in human skin from different age groups for a better understanding of the hormonal regulation of skin aging. Using standard immunohistochemical techniques, biopsies of sun-unprotected and sun-protected skin were taken from 60 normal subjects. Sun-protected skin showed significantly higher immunoreactivity for ERβ and AR compared to sun-unprotected skin of all age groups. Significantly higher ERβ H score and percent of expression were associated with the 20-35 years age group compared to the groups that were 35-50 years and >50 years old (p < 0.02, p = 0.03, respectively) in sun-unprotected and sun-protected skin (p < 0.001, p = 0.01, respectively). AR H score showed a negative correlation with age (p = 0.04) with no significant difference in immunoreactivity in different age groups, either in sun-unprotected or sun-protected skin. There was also a significant correlation between ERβ H score and epidermal thickness in sun-unprotected (p = 0.04) and sun-protected skin (p = 0.04) in studied subjects regardless of age. The same relationships did not reach significance with AR expression. However, a significant positive correlation was detected between H scores and percent of expression of ERβ and AR in sun-unprotected (p = 0.01, p = 0.02, respectively) and sun-protected skin (p = 0.005, p = 0.02, respectively) regardless of age. In conclusion, both ERβ and AR decline gradually with intrinsic and extrinsic aging. This decline is more obvious with extrinsic aging. Further large-scaled studies are recommended to expand, validate and translate current findings to clinically significant, diagnostic and therapeutic applications. Molecular studies to investigate the probable ligand-independent action of both receptors are warranted. In addition, their gene expression patterns and associated signaling and metabolic pathways can also be tackled to provide a basis for further interventions in pathological processes that involve their dysregulation., (© 2016 S. Karger AG, Basel.)
- Published
- 2016
- Full Text
- View/download PDF