Effects of the addition of oocyte meiosis-inhibiting drugs on the expression of maturation-promoting factor components and organization of cytoplasmic organelles

Autor(es)

Maziero, Rosiara Rosaria Dias ^{[1, 2]} ; de Freitas Guaitolini, Carlos Renato ^{[1, 2]} ; Paschoal, Daniela Martins ^[1] ; Crespilho, Andre Maciel ^[3] ; Oliveira Sestari, Danielle Andressa ^[2] ; Nunes Dode, Margot Alves ^[4] ; Landim-Alvarenga, Fernanda da Cruz ^[1]

Afiliação do(s) autor(es)

^[1] Sao Paulo State Univ, Coll Vet Med & Anim Sci, Dept Anim Reprod & Vet Radiol, Botucatu, SP - Brazil

^[2] Univ Paranaense, Dept Anim Reprod, Umuarama, Parana - Brazil

^[3] Univ Santo Amaro, Dept Anim Reprod, Sao Paulo, SP - Brazil

^[4] Embrapa Genet Resources & Biotechnol, Lab Anim Reprod, Brasilia, DF - Brazil

• Tipo de documento: Artigo Científico
• Fonte: REPRODUCTIVE BIOLOGY; v. 20, n. 1, p. 48-62, MAR 2020.
• Citações Web of Science: 0

Resumo

The present study evaluated the effects of the blockade of meiosis in bovine oocytes by the cyclin-dependent kinase inhibitors roscovitine (ROS) and butyrolactone-I (BL-I) on nuclear maturation and extracellular signal-regulated kinase 1/2 (ERK1/2), cyclin B1 and p34(cdc2) protein expression and localization. We also evaluated ultrastructural changes in oocytes. Immature oocytes were obtained from slaughtered bovines and divided into: (1) control (oocytes for in vitro maturation only in tissue culture medium-199 for 24 h), (2) oocytes that were treated with 12.5 mu MROS for 6 h, (3) oocytes that were treated with 50 mu MBL-I for 6 h and (4) oocytes that were treated with 6.25 mu MROS + 25 mu MBL-I for 6 h. Incubation with inhibitors was followed by the reversal of blockade for 18 h. Oocytes then underwent immunohistochemical analysis to visualize chromatin and assess ERK1/2, cyclin B1 and p34 cdc2 localization/expression, followed by preparation of the cells for ultrastructure analysis by electron microscopy. The groups at 6 h of maturation and before IVM exhibited the lowest number of oocytes in metaphase I. ROS group had the highest number of degenerating oocytes (p < 0.05). After maturation, majority of oocytes were in metaphasell with no differences among groups (p > 0.05). ERK1/2, cyclin B1 and p34(cdc2) expression differed throughout inhibition and oocyte maturation (p < 0.05). No difference was observed in the localization of these proteins in the ooplasm. No ultrastructural changes in oocytes were observed between treatments, with the exception of treatment with drugs that augmented lipid metabolism (p < 0.05). Results indicate that the effects of CDK1 inhibitors are reversible in bovine oocytes, indicated by nuclear, cytoplasmic, and molecular maturation parameters. (AU)

• Processo FAPESP: 10/18994-4 - Ação da butirolactona I e da roscovitina na maturação de oócitos bovinos e suas implicações na resistência à criopreservação
• Beneficiário: Rosiára Rosária Dias Maziero
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 11/08926-4 - Ação do forskolin, da butirolactona I e da roscovitina na maturação de oócitos bovinos e suas implicações na resistência à criopreservação
• Beneficiário: Fernanda da Cruz Landim
• Modalidade de apoio: Auxílio à Pesquisa - Regular