摘要
Background: Androgens have been implicated in androgenic alopecia as evidenced by the increased cutaneous expression of androgen receptor (AR), 5α-reductase, and decreased aromatase. Abnormalities of the AR-signal transduction pathway probably participate in the development of androgenic alopecia. ARA70/ELE1 is an AR coactivator with two isoforms, one full-length form (ARA70α/ELE1α), and a n internally deleted form (ARA70β/ELE1β). We decided to examine the cutaneous expression of both isoforms in male androgenic alopecia. Methods: Formalin-fixe d, paraffin-embedded tissue sections from seven subjects with androgenic alopec ia with matched punch biopsies from non-balding and balding areas were examined by in situ hybridization. Results: Expression of at least one of the two probes for ARA70/ELE1 was present in all phases of the hair-growth cycle in all epith elial hair structures except for the inner root sheath. The dermal papilla and h air bulb expressed only the short (β) but not the long (α) form of ARA70/ELE1. In situ labeling for ARA70β/ELE1βwas weaker in the dermal papilla of balding recipient areas than those from donor ones. Conclusions: Our data further suppor t that the hair growth is regulated by androgens. The differential expression pa ttern of ARA70/ELE1 suggests that this key androgen receptor coactivator is invo lved in androgenic alopecia.
Background: Androgens have been implicated in androgenic alopecia as evidenced by the increased cutaneous expression of androgen receptor (AR), 5α-reductase, and decreased aromatase. Abnormalities of the AR-signal transduction pathway probably participate in the development of androgenic alopecia. ARA70/ELE1 is an AR coactivator with two isoforms, one full-length form (ARA70α/ELE1α), and a n internally deleted form (ARA70β/ELE1β). We decided to examine the cutaneous expression of both isoforms in male androgenic alopecia. Methods: Formalin-fixe d, paraffin-embedded tissue sections from seven subjects with androgenic alopec ia with matched punch biopsies from non-balding and balding areas were examined by in situ hybridization. Results: Expression of at least one of the two probes for ARA70/ELE1 was present in all phases of the hair-growth cycle in all epith elial hair structures except for the inner root sheath. The dermal papilla and h air bulb expressed only the short (β) but not the long (α) form of ARA70/ELE1. In situ labeling for ARA70β/ELE1βwas weaker in the dermal papilla of balding recipient areas than those from donor ones. Conclusions: Our data further suppor t that the hair growth is regulated by androgens. The differential expression pa ttern of ARA70/ELE1 suggests that this key androgen receptor coactivator is invo lved in androgenic alopecia.
