Effects of testosterone administration on growth hormone pulse dynamics in human immunodeficiency virus-infected women.
The effects of testosterone administration on the GH axis in androgen-deficient HIV-infected women are unknown. In this study, we determined the effects of transdermal testosterone administration on GH secretory dynamics and pulse characteristics in this population. GH-IGF-I parameters were determined in response to testosterone (4.1 mg/patch, twice a week; estimated delivery rate, 150 microg/d) vs. placebo over 6 months in 31 HIV-infected women. IGF-I increased significantly in the testosterone-treated compared with the placebo-treated patients [37 (-4, 73) vs. -30 (-98, 39) ng/ml, P = 0.01; 4.8 (-0.5, 9.6) vs. -3.9 (-12.8, 5.1) nmol/liter]. GH pulse frequency increased significantly in the testosterone-treated compared with the placebo-treated subjects [1.0 (1.0, 2.0) vs. 0.0 (-0.5, 1.5) peaks per 12 h, respectively; P = 0.02]. Before testosterone administration, overnight GH pulse amplitude was significantly related to IGF-I in univariate (r = 0.41, P = 0.03) and multivariate regression analysis; however, free testosterone, estradiol, and body mass index were not significantly correlated with baseline IGF-I. In contrast, after 6 months of treatment with testosterone, the change in IGF-I was significantly correlated to the change in free testosterone in univariate (r = 0.40, P = 0.04) and multivariate regression analysis. For each 1.0 pg/ml (3.5 pmol/liter) increase in free testosterone, IGF-I increased 19 ng/ml (2.5 nmol/liter), controlling for estradiol, body mass index, and GH pulse parameters (r(2) = 0.64). We demonstrate that IGF-I increases in response to physiologic, transdermal testosterone in HIV-infected women. The mechanism of this effect is unknown, but may involve a direct effect of testosterone on IGF-I, independent of changes in GH pulse dynamics.
Schurgin
Sunita
S
Program in Nutritional Metabolism, Longfellow 207, Massachusetts General Hospital, 55 Fruit Street, Boston, MA 02114, USA.
Dolan
Sara
S
Perlstein
Ari
A
Sullivan
Meghan P
MP
Aliabadi
Negar
N
Grinspoon
Steven
S
D000279:Administration, Cutaneous; D000328:Adult; D004958:Estradiol / Q000097:blood; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000378:metabolism*; D019382:Human Growth Hormone / Q000378:metabolism*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008875:Middle Aged; D013739:Testosterone / Q000008:administration & dosage / Q000097:blood / Q000627:therapeutic use*
D019382:Human Growth Hormone; D013739:Testosterone; D004958:Estradiol; D007334:Insulin-Like Growth Factor I