The effect of midazolam on mouse Leydig cell steroidogenesis and apoptosis.
The peripheral-type benzodiazepine receptor (PBR), a putative receptor in Leydig cells, modulates steroidogenesis. Since benzodiazepines are commonly used in regional anesthesia, their peripheral effects need to be defined. Therefore, this study set out to investigate in vitro effects of the benzodiazepine midazolam (MDZ) on Leydig cell steroidogenesis, and the possible underlying mechanisms. The effects of MDZ on steroidogenesis in primary mouse Leydig cells and MA-10 Leydig tumor cells were determined by radioimmunoassay. PBR, P450scc, 3beta-HSD and StAR protein expression induced by MDZ was determined by Western blotting. Inhibitors of the signal transduction pathway and a MDZ antagonist were used to investigate the intracellular cascades activated by MDZ. In both cell types, MDZ-stimulated steroidogenesis in dose- and time-dependent manners, and induced the expression of PBR and StAR proteins, but had no effect on P450scc and 3beta-HSD expressions. Moreover, H89 (PKA inhibitor) and GF109203X (PKC inhibitor) attenuated MDZ-stimulated steroid production. Interestingly, the MDZ antagonist (flumazenil) did not decrease MDZ-induced steroid production in both cell types. These results highly indicated that MDZ-induced steroidogenesis in mouse Leydig cells via PKA and PKC pathways, along with the expression of PBR and StAR proteins. In addition, MDZ at high dosages induced rounding-up, membrane blebbing, and then death in MA-10 cells. In conclusion, midazolam could induce Leydig tumor cell steroidogenesis, and high dose of midazolam could induce apoptosis in Leydig tumor cells.
Department of Anesthesia, Chi-Mei Medical Center, Tainan, Taiwan, ROC.
Edmund Cheung
EC
So
Ya-Ting
YT
Chang
Chung-His
CH
Hsing
Paul Wai-Fung
PW
Poon
Sew-Fen
SF
Leu
Bu-Miin
BM
Huang
D000777:Anesthetics / Q000633:toxicity*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D005442:Flumazenil / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects; D007211:Indoles / Q000494:pharmacology; D007546:Isoquinolines / Q000494:pharmacology; D007985:Leydig Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008301:Maleimides / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D008874:Midazolam / Q000633:toxicity*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D013256:Steroids / Q000096:biosynthesis*; D013449:Sulfonamides / Q000494:pharmacology
D000777:Anesthetics; D007211:Indoles; D007546:Isoquinolines; D008301:Maleimides; D047428:Protein Kinase Inhibitors; D013256:Steroids; D013449:Sulfonamides; D005442:Flumazenil; D011493:Protein Kinase C; C070515:bisindolylmaleimide I; C063509:N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide; D008874:Midazolam