title: The effect of hormonal estrus induction on maternal effect and apoptosis-related genes expression in porcine cumulus-oocyte complexes.
abstract: BACKGROUND
  The effect of hormonal estrus induction on maternal effect (MATER - maternal antigen that embryo requires, ZAR-1 - zygote arrest 1, and BMP15 - bone morphogenetic protein 15) and apoptosis-related genes expression (BCL-2 and BAX) in porcine cumulus-oocyte complexes (COCs) and selected follicular parameters was investigated in this study.
  
  
  METHODS
  Gilts were divided into three groups: (I) with natural estrus; (II) stimulated with PMSG/hCG; and (III) with PMSG/hCG + PGF2alpha. Analysis of maternal effect and apoptosis-related transcripts expression in COCs, and progesterone synthesis pathway genes expression (P450scc and 3betaHSD) in granulosa cells was performed by qPCR. BMP15 protein expression in follicular fluid (FF) was analyzed by western blot. Oocyte nuclear maturation was assessed by aceto-orcein staining. Progesterone (P4) and estradiol (E2) concentrations in FF and serum were measured by ELISA. Data were analyzed with the one-way ANOVA and Bonferroni post-test or Kruskal-Wallis test and Dunns post-test.
  
  
  RESULTS
  The highest expression of MATER, ZAR-1, and BMP15 genes was found in COCs recovered from gilts treated with PMSG/hCG when compared to PMSG/hCG + PGF2alpha-stimulated or non-stimulated gilts. Hormonal treatment did not affect the BMP15 protein expression in FF, but increased the expression of genes participating in P4 synthesis in granulosa cells. The higher percentage of immature oocytes was found in PMSG/hCG-treated when compared to the non-stimulated gilts. The expression of BCL-2 and BAX mRNA, and BCL-2/BAX mRNA ratio was significantly higher in COCs derived from PMSG/hCG-treated when compared to PMSG/hCG + PGF2alpha-treated or non-stimulated subjects. The level of P4 in serum was similar in animals from all experimental groups, while its concentration in FF was greater in gilts subjected to PMSG/hCG treatment than in PMSG/hCG + PGF2alpha-stimulated and non-stimulated gilts. The concentration of E2 did not differ in the serum or FF between the control group and the hormonally stimulated groups.
  
  
  CONCLUSIONS
  Hormonal induction of estrus affected maternal effect gene transcripts levels in COCs and and oocyte nuclear maturation. The inclusion of PGF2alpha into the stimulation protocol enabled maintaining of physiological concentration of P4 in FF. Additionally, both hormonal treatments seem to be beneficial for apoptosis prevention through increasing BCL-2/BAX transcript ratio.
authors.affiliation: Institute of Animal Reproduction and Food Research of Polish Academy of Sciences, Tuwima 10, Olsztyn 10-748, Poland. m.bogacki@pan.olsztyn.pl.
authors.forename: Marek
authors.initials: M
authors.lastname: Bogacki
authors.forename: Marta
authors.initials: M
authors.lastname: Wasielak
authors.forename: Anna
authors.initials: A
authors.lastname: Kitewska
authors.forename: Iwona
authors.initials: I
authors.lastname: Bogacka
authors.forename: Beenu Moza
authors.initials: BM
authors.lastname: Jalali
mesh_terms: D000818:Animals; D001324:Autoantigens / Q000235:genetics / Q000378:metabolism; D055430:Bone Morphogenetic Protein 15 / Q000235:genetics / Q000378:metabolism; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D054885:Cumulus Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D015237:Dinoprost / Q000494:pharmacology; D004527:Egg Proteins / Q000235:genetics / Q000378:metabolism; D004971:Estrus / Q000187:drug effects; D005260:Female; D005300:Fertility Agents, Female / Q000494:pharmacology*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects*; D006064:Gonadotropins, Equine / Q000494:pharmacology; D054315:Oocyte Retrieval / Q000662:veterinary; D009865:Oocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D009866:Oogenesis / Q000187:drug effects; D010062:Ovulation Induction / Q000662:veterinary*; D011374:Progesterone / Q000097:blood / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism*; D034421:Sus scrofa / Q000502:physiology*; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism
chemical_list: D001324:Autoantigens; D055430:Bone Morphogenetic Protein 15; D006063:Chorionic Gonadotropin; D004527:Egg Proteins; D005300:Fertility Agents, Female; D006064:Gonadotropins, Equine; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; D011374:Progesterone; D015237:Dinoprost