Age-Related Changes in Glucocorticoid and Androgen Receptors of Cultured Human Pubic Skin Fibroblasts

Abstract
In order to evaluate age-related changes in glucocorticoid receptor and androgen receptor of cultured human pubic skin fibroblasts in young and aged men, we determined both [3H]dexamethasone binding and [3H]methyltrienolone (R1881, potent androgenic steroid) binding, using dispersed whole cell assay. Scatchard analyses of specific [3H]dexamethasone binding to the fibroblasts of young and aged men showed a single class of high-affinity binding sites with a mean ( ± SD) binding site concentration (Bmax) of 12.69 ± 2.36 × 104 and 12.87 ± 12.21 X 104 sites/cell, respectively, and mean ( ± SD) dissociation constant (Kd) of 5.60 ± 0.41 and 7.36 ± 2.17 nM, respectively. Scatchard analyses of specific [3H]R1881 binding to the same cultured skin fibroblasts of young and aged men showed a single class of high-affinity binding sites with a mean Bmax of 5.77 ± 1.02 × 103 and 2.82 ± 0.97 × 103 sites/cell, respectively, and a mean Kd of 0.56 ± 0.23 and 0.50 ± 0.28 nM, respectively. These findings indicate that there were no significant age-related changes in binding site and affinity of glucocorticoid receptor in cultured human pubic skin fibroblasts, whereas binding sites of androgen receptor significantly decreased in those of aged men as compared to young men, without significant change in affinity.