title: Induction of heparanase in bovine granulosa cells by luteinizing hormone: possible role during the ovulatory process.
abstract: Follicular development, follicular rupture, and corpus luteum (CL) formation are accompanied by extensive tissue remodeling. We examined whether heparanase (HPSE), which cleaves heparan sulfate glycosaminoglycans, is induced during these processes. Prostaglandin F2alpha injection, which initiated luteolysis and the development of a preovulatory follicle, moderately increased HPSE mRNA in bovine granulosa cells (GCs). GnRH, used to induce gonadotropin surge, markedly augmented HPSE mRNA levels 12 h after its injection. The temporal pattern of HPSE gene expression in follicular-luteal transition was further examined in follicles collected before, and 4, 10, 20, 25, and 60 h after GnRH injection. HPSE mRNA increased transiently 10-20 h after GnRH injection to levels 10-fold higher than in untreated heifers. HPSE protein levels were similarly elevated 20 h after GnRH injection in GCs, but not in the theca layer. Cyclooxygenase-2 (PTGS2) mRNA peaked before ovulation when HPSE levels returned to baseline levels. HPSE mRNA abundance also remained low in the CLs. The antiprogesterone, RU-486, elevated HPSE levels in GC culture, suggesting that progesterone secreted by CLs may inhibit HPSE. HPSE immunostaining was more abundant in GCs than thecae. In cultured GCs, LH induced a transient increase in HPSE mRNA 3-6 h after its addition, but not at 24 h. However, PTGS2 mRNA was clearly induced at this time. These findings suggest that: 1) HPSE may play a role in ovulation but much less so during CL development, and 2) GC-derived HSPE may be a novel member of the LH-induced extracellular matrix-degrading enzyme family and may contribute to follicular rupture.
authors.affiliation: Department of Animal Sciences, Faculty of Agricultural, Food and Environmental Quality Sciences, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
authors.forename: Eyal
authors.initials: E
authors.lastname: Klipper
authors.forename: Ehud
authors.initials: E
authors.lastname: Tatz
authors.forename: Tatiana
authors.initials: T
authors.lastname: Kisliouk
authors.forename: Israel
authors.initials: I
authors.lastname: Vlodavsky
authors.forename: Uzi
authors.initials: U
authors.lastname: Moallem
authors.forename: Dieter
authors.initials: D
authors.lastname: Schams
authors.forename: Yaniv
authors.initials: Y
authors.lastname: Lavon
authors.forename: David
authors.initials: D
authors.lastname: Wolfenson
authors.forename: Rina
authors.initials: R
authors.lastname: Meidan
mesh_terms: D000818:Animals; D001141:Aromatase / Q000235:genetics; D002417:Cattle; D005260:Female; D005786:Gene Expression Regulation; D005966:Glucuronidase / Q000096:biosynthesis / Q000235:genetics*; D007987:Gonadotropin-Releasing Hormone / Q000502:physiology; D006107:Granulosa Cells / Q000187:drug effects / Q000201:enzymology*; D007774:Lactation / Q000502:physiology; D007986:Luteinizing Hormone / Q000494:pharmacology* / Q000502:physiology; D006080:Ovarian Follicle / Q000187:drug effects / Q000502:physiology; D010060:Ovulation; D016133:Polymerase Chain Reaction; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D012333:RNA, Messenger / Q000235:genetics; D000099175:Heparanase
chemical_list: D001141:Aromatase; D005966:Glucuronidase; D007987:Gonadotropin-Releasing Hormone; D007986:Luteinizing Hormone; D012313:RNA; D012333:RNA, Messenger; D000099175:Heparanase