Inhibition of apoptosis in cultured immature rat Leydig cells by human chorionic gonadotropin associated with Bcl-2 mRNA expression.
Bcl-2 is the first identified negative regulator of apoptotic cell death. When the level of Bcl-2 mRNA in rat whole testes was examined in the present study, it gradually decreased in rats from 2.5 to 9 weeks old. We also examined the effect of human chorionic gonadotropin (hCG) on apoptosis and the level of Bcl-2 mRNA expression in immature Leydig cells in vitro. When the cells were cultured with serum free media (SFM), Bcl-2 mRNA levels gradually decreased. On the other hand, the level of Bcl-2 mRNA in cells treated with 50 ng/ml of hCG decreased at 6 h, but increased after 12 h. At 24 h, the level of Bcl-2 mRNA in the treated cells was almost the same as that of control cells (time = 0). At 12 h after the addition of various concentrations (from 0.1-1000 ng/ml) of hCG, Bcl-2 mRNA levels increased in a dose-dependent manner. An analysis of DNA fragmentation showed that treatment with hCG prevents the apoptosis of immature Leydig cells. Our findings suggest that Bcl-2 mRNA may be related to the programmed cell death of immature rat Leydig cells in vitro, which are inhibited by hCG.
Fujisawa
M
M
Department of Urology, Kobe University School of Medicine, Japan. masato@med.kobe-u.ac.jp
Kanzaki
M
M
Tatsumi
N
N
Okuda
Y
Y
Okada
H
H
Arakawa
S
S
Kamidono
S
S
D000818:Animals; D000831:Animals, Newborn / Q000502:physiology; D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000494:pharmacology*; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D053938:DNA Fragmentation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007985:Leydig Cells / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D008297:Male; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013737:Testis / Q000378:metabolism; D013997:Time Factors
D006063:Chorionic Gonadotropin; D016895:Culture Media, Serum-Free; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger