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Titolo:
PANHYPOPITUITARISM AS A MODEL TO STUDY THE METABOLISM OF DEHYDROEPIANDROSTERONE (DHEA) IN HUMANS
Autore:
YOUNG J; COUZINET B; NAHOUL K; BRAILLY S; CHANSON P; BAULIEU EE; SCHAISON G;
Indirizzi:
HOP BICETRE,SERV ENDOCRINOL & MALAD REPROD F-94275 LE KREMLIN BICETR FRANCE HOP BICETRE,LAB BIOCHIM HORMONALE F-94275 LE KREMLIN BICETR FRANCE HOP BICETRE,INSERM,U33 F-94275 LE KREMLIN BICETR FRANCE HOP BICETRE,IFR 21 F-94275 LE KREMLIN BICETR FRANCE
Titolo Testata:
The Journal of clinical endocrinology and metabolism
fascicolo: 8, volume: 82, anno: 1997,
pagine: 2578 - 2585
SICI:
0021-972X(1997)82:8<2578:PAAMTS>2.0.ZU;2-1
Fonte:
ISI
Lingua:
ENG
Soggetto:
HUMAN LIVER; 17-BETA-HYDROXYSTEROID DEHYDROGENASE; ORAL DEHYDROEPIANDROSTERONE; UNCONJUGATED STEROIDS; POSTMENOPAUSAL WOMEN; PLASMA; MEN; SULFOTRANSFERASE; AGE; RAT;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
36
Recensione:
Indirizzi per estratti:
Citazione:
J. Young et al., "PANHYPOPITUITARISM AS A MODEL TO STUDY THE METABOLISM OF DEHYDROEPIANDROSTERONE (DHEA) IN HUMANS", The Journal of clinical endocrinology and metabolism, 82(8), 1997, pp. 2578-2585

Abstract

The physiological importance and therapeutical interest of dehydroepiandrosterone (DHEA) and its sulfate ester (DHEAS), are still controversial. Panhypopituitarism is characterized by the absence of secretion of adrenal and gonadal steroids and thus the production of their metabolites. The conversion of DHEA given orally into Delta 5 derivatives. androgens, androgen metabolites, and estrogens was studied in ten patients with complete panhypopituitarism. Sex steroid therapy was withdrawn for at least 2 months. Each patient received, at 1-month intervals and in a random order, two single oral doses of DHEA (50 mg and 200 mg) and placebo. During each treatment, urine samples were collected for24 h, and blood samples were drawn at hourly intervals For 8 h. In patients with pituitary deficiency, plasma DHEA and DHEAS were not detectable and increased, with the 50 mg dose, up to levels observed in young adults. The administration of 200 mg of DHEA induced an increase ofboth steroids to supraphysiological plasma levels. A small increase of Delta 5-androstenediol was observed. In contrast, the increase of plasma Delta 4-androstenedione was important and dose dependent. DHEA was also converted into the potent sex steroid testosterone (T). The administration of a 50 mg dose of DHEA restored plasma T to levels similar to those observed in young women. The 200 mg dose induced an important increase of plasma T, slightly below the levels observed in normal men. The increase of plasma dihydrotestosterone levels was small at both doses of DHEA, in contrast with the large conversion of DHEA into androsterone glucuronide and androstanediol glucuronide. Finally, DHEA administration induced a significant and dose dependent increase of plasma estrogens and particularly of Estradiol.In conclusion, this shortterm study demonstrates that: 1) panhypopituitarism is a model of interest to study the metabolism of DHEA; 2) in the absence of pituitary hormones and of adrenal and gonadal steroids, DHEA given orally is mainly converted into Delta 4 derivatives, which in turn are strongly metabolized into 5 alpha-3keto-reduced steroids; 3) a significant increase of sex active hormones was observed in plasma after 200 and even 50 mg of DHEA. Thus, biotransformation of DHEA into potent androgens and estrogens may explain several of the reported beneficial actions of this steroid in aging people.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 27/11/20 alle ore 23:45:14