| Texto completo | |
| Autor(es): |
Cavallari, Fernanda de Castro
[1, 2, 3]
;
Verde Leal, Claudia Lima
[1]
;
Zvi, Roth
[4]
;
Hansen, Peter J.
[2, 3]
Número total de Autores: 4
|
| Afiliação do(s) autor(es): | [1] Univ Sao Paulo, Fac Anim Sci & Food Engn, Dept Vet Med, BR-13635900 Pirassununga - Brazil
[2] Univ Florida, DH Barron Reprod & Perinatal Biol Res Program, Dept Anim Sci, Gainesville, FL 32611 - USA
[3] Univ Florida, Genet Inst, Gainesville, FL 32611 - USA
[4] Hebrew Univ Jerusalem, Robert H Smith Fac Agr Food & Environm, Dept Anim Sci, IL-76100 Rehovot - Israel
Número total de Afiliações: 4
|
| Tipo de documento: | Artigo Científico |
| Fonte: | ZYGOTE; v. 27, n. 3, p. 180-186, JUN 2019. |
| Citações Web of Science: | 2 |
| Resumo | |
Heat shock may disrupt oocyte function by increasing the generation of reactive oxygen species (ROS). We evaluated the capacity of the antioxidant melatonin to protect oocytes using two models of oxidative stress - heat shock and the pro-oxidant menadione. Bovine cumulus-oocyte complexes (COC) were exposed in the presence or absence of 1 mu M melatonin to the following treatments during maturation: 38.5 degrees C, 41 degrees C and 38.5 degrees C+5 mu M menadione. In the first experiment, COC were matured for 3 h with 5 mu M CellROX (R) and analyzed by epifluorescence microscopy to quantify production of ROS. The intensity of ROS was greater for oocytes exposed to heat shock and menadione than for control oocytes. Melatonin reduced ROS intensity for heat-shocked oocytes and oocytes exposed to menadione, but not for control oocytes. In the second experiment, COC were matured for 22 h. After maturation, oocytes were fertilized and the embryos cultured for 7.5 days. The proportion of oocytes that cleaved after fertilization was lower for oocytes exposed to heat shock and menadione than for control oocytes. Melatonin increased cleavage for heat-shocked oocytes and oocytes exposed to menadione, but not for control oocytes. Melatonin tended to increase the developmental competence of embryos from heat-shocked oocytes but not for embryos from oocytes exposed to menadione or from control oocytes. In conclusion, melatonin reduced production of ROS of maturing oocytes and protected oocytes from deleterious effects of both stresses on competence of the oocyte to cleave after coincubation with sperm. These results suggest that excessive production of ROS compromises oocyte function. (AU) | |
| Processo FAPESP: | 15/20379-0 - Estudos sobre a melatonina na função e qualidade de complexos cumulus-oócitos bovinos |
| Beneficiário: | Cláudia Lima Verde Leal |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 17/04376-6 - Estudo funcional do receptor de melatonina MT1 em complexos cumulus-oócitos bovinos e sua importância na maturação oocitária e desenvolvimento embrionário in vitro sob condições normais e de estresse térmico |
| Beneficiário: | Fernanda Cavallari de Castro |
| Modalidade de apoio: | Bolsas no Exterior - Estágio de Pesquisa - Doutorado |