title: Influence of age on metabolism of testosterone, dihydrotestosterone, and 3-alpha-androstanediol in muscle biopsies from patients with neuromuscular diseases.
abstract: We investigated the possible effect of age on the metabolism of androgens in muscle biopsies from patients with neuromuscular diseases. The conversion of testosterone, dihydrotestosterone (DHT) and 5-alpha-androstane-3-alpha-17-beta-diol (3-alpha-androstanediol) was measured in muscle biopsies from 24 patients with neuromuscular diseases and seven controls. The reductive metabolism of 3-alpha-HSDH was significantly higher than the oxidative metabolism. Significant metabolism of testosterone to DHT was not found. Only the age of the patients emerged as a significant negative predictor in a stepwise multiple linear regression model for V(max) and K(m) (Lineweaver-Burke plots) of the reductive metabolism of 3-alpha-HSDH. Therefore, altered metabolism of anabolic androgens in skeletal muscles could be demonstrated. We conclude that this could alter the androgenic catabolic/anabolic balance in the (androgenic target organ) skeletal muscle.
authors.affiliation: Neurological Department, University Hospital Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany.
authors.forename: H J
authors.initials: HJ
authors.lastname: Stuerenburg
authors.forename: B
authors.initials: B
authors.lastname: Schoser