title: Insulin-like growth factor II (IGF-II) and follicle stimulating hormone (FSH) combinations can improve the in vitro development of grown oocytes enclosed in caprine preantral follicles.
abstract: OBJECTIVE
  Evaluate the possible role of IGF-II alone or in association with FSH on in vitro development of isolated caprine preantral follicles.
  
  
  METHODS
  Preantral follicles (≥150 μm) were isolated from goat ovaries and cultured for 18 days in basic αMEM medium (control) or supplemented with IGF-II alone at 20 or 50 ng/ml, named IGF20 and IGF50, respectively, or in combination with recombinant FSH (FSH, IGF20F or IGF50F). During in vitro culture, the follicles were analyzed by using morphology criteria, antrum formation and growth rate as parameters. After 18 days of follicular culture, oocytes equal to or larger than 110 μm were used for in vitro maturation (IVM). Oocyte viability and meiosis resumption were assessed by fluorescence microscopy after labeling with calcein-AM, ethidium homodimer and Hoechst 33342.
  
  
  RESULTS
  The IGF20 treatment was the only treatment capable of maintaining the percentage of morphologically normal follicles from D0 until D6 and from D12 to D18 (p>0.05), while in all other treatments the percentage of morphologically normal follicles decreased progressively during 18 days of in vitro culture (p<0.05). At D18, all treatments with IGF-II or FSH resulted in a significantly higher percentage of normal follicles when compared to αMEM alone. The IGF50F treatment provided a significantly higher early antrum formation rate when compared to αMEM and FSH alone. The addition of IGF-II alone (20 or 50 ng/ml) or in combination with FSH prevented oocyte degeneration after IVM. Moreover, the FSH treatment demonstrated a lower percentage of oocyte degeneration when compared to control (4.35% vs. 26.3%, respectively; p<0.05). Regarding meiosis resumption, the IGF20F treatment was the only treatment that significantly differed from αMEM alone. All treatments except the control (αMEM alone) presented oocytes at metaphase II.
  
  
  CONCLUSIONS
  IGF-II associated with FSH stimulated in vitro follicular development, oocyte viability and meiotic resumption of caprine oocytes after IVM.
authors: Laboratory of Manipulation of Oocytes and Preantral Follicles, Faculty of Veterinary, State University of Ceará, Fortaleza, Ceará, Brazil. beatriz_duarte34@yahoo.com.br
authors: Ana Beatriz Graça
authors: AB
authors: Duarte
authors: Valdevane Rocha
authors: VR
authors: Araújo
authors: Roberta Nogueira
authors: RN
authors: Chaves
authors: Gerlane Modesto
authors: GM
authors: da Silva
authors: Valesca Barreto
authors: VB
authors: Luz
authors: Keith Thomas
authors: KT
authors: Haag
authors: Deborah Melo
authors: DM
authors: Magalhães-Padilha
authors: Anderson Pinto
authors: AP
authors: Almeida
authors: Carlos Henrique
authors: CH
authors: Lobo
authors: Cláudio Cabral
authors: CC
authors: Campello
authors: José Ricardo
authors: JR
authors: de Figueiredo
mesh_terms: D000818:Animals; D048429:Cell Size / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003470:Culture Media / Q000494:pharmacology; D005260:Female; D005640:Follicle Stimulating Hormone / Q000008:administration & dosage / Q000494:pharmacology*; D006041:Goats / Q000502:physiology; D059471:In Vitro Oocyte Maturation Techniques / Q000379:methods* / Q000662:veterinary; D007335:Insulin-Like Growth Factor II / Q000008:administration & dosage / Q000494:pharmacology*; D009865:Oocytes / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D009866:Oogenesis / Q000187:drug effects / Q000502:physiology; D006080:Ovarian Follicle / Q000166:cytology / Q000187:drug effects* / Q000502:physiology
chemical_list: D003470:Culture Media; D007335:Insulin-Like Growth Factor II; D005640:Follicle Stimulating Hormone