TITLE
Comparison of finasteride (Proscar), a 5 alpha reductase inhibitor, and
various commercial plant extracts in in vitro and in vivo 5 alpha reductase
inhibition.
AUTHOR
Rhodes L; Primka RL; Berman C; Vergult G; Gabriel M; Pierre-Malice M;
Gibelin B
ORGANISATION
Department of Biochemistry, Merck Research Laboratories, Rahway, New Jersey
07065.
SOURCE
Prostate 1993; 22 (1): 43-51
LANGUAGE OF PUBLICATION
English
ABSTRACT
Human prostate was used as a source of 5 alpha reductase. Compounds were
incubated with an enzyme preparation and [3H]testosterone.
[3H]-dihydrotestosterone production was measured to calculate 5 alpha reductase
activity. IC50 values (ng/ml) were finasteride=1; Permixon=5,600; Talso=7,000;
Strogen Forte=31,000; Prostagutt=40,000; and Tadenan=63,000. Bazoton and Harzol
had no activity at concentrations up to 500,000 ng/ml. In castrate rats
stimulated with testosterone (T) or dihydrotestosterone (DHT), finasteride, but
not Permixon or Bazoton, inhibited T stimulated prostate growth, while none of
the three compounds inhibited DHT stimulated growth. These results demonstrate
that finasteride inhibits 5 alpha reductase, while Permixon and Bazoton have
neither anti-androgen nor 5 alpha reductase inhibitory activity. In addition,
in a 7 day human clinical trial, finasteride, but not Permixon or placebo,
decreased serum DHT in men, further confirming the lack of 5 alpha reductase
inhibition by Permixon. Finasteride and the plant extracts listed above do not
inhibit the binding of DHT to the rat prostatic androgen receptor
(concentrations to 100 micrograms/ml). Based on these results, it is unlikely
that these plant extracts would shrink the prostate by inhibiting androgen
action or 5 alpha reductase. (AUTHOR)
MJTR: Androstenes PD. Azasteroids PD. Plant
Extracts PD. Testosterone 5-alpha-Reductase AI.
MNTR: Animal. Comparative Study. Human. In
Vitro. Male. Prostate DE. Prostate EN. Rats. Receptors, Androgen DE. Stanolone
BL. Testosterone BL. CLINICAL TRIAL. CONTROLLED CLINICAL TRIAL. JOURNAL
ARTICLE
RNUM: EC 1.3.99.5 (Testosterone
5-alpha-Reductase); 0 (Androstenes); 0 (Azasteroids); 0 (Permixon); 0 (Plant
Extracts); 0 (Receptors, Androgen); 521-18-6 (Stanolone); 57-85-2
(Testosterone); 98319-26-7 (Finasteride)
GEOT: UNITED STATES
IDEN: ISSN: 0270-4137. JOURNAL-CODE: PB4.
ENTRY-DATE: 930226. JOURNAL-SUBSET: M X. IM-DATE: 9305.
ACCE: 93149919