Effects of evodiamine on the secretion of testosterone in rat testicular interstitial cells.
Lin H, Tsai SC, Chen JJ, Chiao YC, Wang SW, Wang GJ, Chen CF, Wang PS.
Department of Physiology, School of Life Science, and School of Medicine, National Yang-Ming University, Taipei, Taiwan, Republic of China.
Evodiamine, a bioactive
component isolated from the Chinese medicine Wu-chu-yu, exhibits vasodilative
and antianoxic action.
Although evodiamine indeed has many biological effects, its effects on the
endocrine system are not clear.
The present study explored the effects of evodiamine on testosterone secretion
in vitro.
Rat collagenase-dispersed testicular interstitial cells (TICs) were incubated
with evodiamine (0 to 10(-4) mol/L) in the presence or absence of human chorionic
gonadotropin (hCG), forskolin, 8-bromo-adenosine 3':5'-cyclic monophosphate
(8-Br-cAMP), or steroidogenic precursors (including 25-hydroxycholesterol,
pregnenolone, progesterone, 17alpha-hydroxyprogesterone, and androstenedione)
at 34 degrees C for 1 hour. The testosterone concentration in the media samples
was measured by radioimmunoassay. Evodiamine 10(-4) mol/L was effective to
reduce both basal and hCG-stimulated testosterone secretion in rat TICs after
1, 2, or 4 hours of incubation.
The stimulatory effect of forskolin on testosterone release in TICs was prevented
by administration of evodiamine. Evodiamine 10(-4) mol/L also decreased
8-Br-cAMP- and androstenedione-stimulated testosterone
secretion.
These results suggest that evodiamine reduces testosterone secretion in rat
TICs via a mechanism involving reduced activity of cAMP-related pathways and
17beta-hydroxysteroid dehydrogenase (17beta-HSD).