title: Group IVA phospholipase A2 regulates testosterone biosynthesis by murine Leydig cells and is required for timely sexual maturation.
abstract: In the present paper, we report that PLA2G4A (Group IVA phospholipase A2) is important in the development and function of rodent testes. Interstitial cells of rat testes had high PLA2 (phospholipase A2) activity that was very sensitive to the PLA2G4A-preferential inhibitor AACOCF3 (arachidonyl trifluoromethyl ketone). PLA2G4A protein was expressed primarily in the interstitial cells of wild-type mouse testes throughout maturation. Although Pla2g4a knockout (Pla2g4a-/-) male mice are fertile, their sexual maturation was delayed, as indicated by cauda epididymal sperm count and seminal vesicle development. Delayed function of Pla2g4a-/- mice testes was associated with histological abnormalities including disorganized architecture, swollen appearance and fewer interstitial cells. Basal secretion of testosterone was attenuated significantly and steroidogenic response to hCG (human chorionic gonadotropin) treatment was reduced in Pla2g4a-/- mice compared with their Pla2g4a+/+ littermates during the sexual maturation period. Chemical inhibition of PLA2G4A activity by AACOCF3 or pyrrophenone significantly reduced hCG-stimulated testosterone production in cultured rat interstitial cells. AACOCF3 inhibited forskolin- and cAMP analogue-stimulated testosterone production. These results provide the first evidence that PLA2G4A plays a role in male testes physiology and development. These results may have implications for the potential clinical use of PLA2G4A inhibitors.
authors.affiliation: Department of Anesthesia and Critical Care, Massachusetts General Hospital, Boston, MA 02114, U.S.A.
authors.forename: Shiro
authors.initials: S
authors.lastname: Kurusu
authors.forename: Adam
authors.initials: A
authors.lastname: Sapirstein
authors.forename: Harumi
authors.initials: H
authors.lastname: Sawada
authors.forename: Mitsumori
authors.initials: M
authors.lastname: Kawaminami
authors.forename: Joseph V
authors.initials: JV
authors.lastname: Bonventre
mesh_terms: D000367:Age Factors; D000818:Animals; D002478:Cells, Cultured; D054500:Group IB Phospholipases A2 / Q000037:antagonists & inhibitors / Q000172:deficiency / Q000502:physiology; D054513:Group IV Phospholipases A2 / Q000037:antagonists & inhibitors / Q000502:physiology*; D006801:Humans; D007985:Leydig Cells / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D051381:Rats; D012741:Sexual Maturation / Q000502:physiology*; D013739:Testosterone / Q000096:biosynthesis* / Q000737:chemistry
chemical_list: D013739:Testosterone; D054500:Group IB Phospholipases A2; D054513:Group IV Phospholipases A2; C516389:PLA2G4A protein, human; C516203:Pla2g1b protein, mouse; C516204:Pla2g1b protein, rat