Camargo Luiz Sergio Almeida, Costa Fernanda Queiros, Munk Michele, Wohlres-Viana Sabine, Serapião Raquel Varela, Carvalho Bruno Campos, Campos Paulo Henrique, Vieira Alex Cabral, Nogueira Luiz Altamiro Garcia, Viana Joao Henrique Moreira
Brazilian Agricultural Research Corporation (Embrapa), Dairy Cattle, Juiz de Fora, Brazil.
UENF, Campos dos Goytacazes, Brazil.
Reprod Domest Anim. 2019 Oct;54(10):1357-1365. doi: 10.1111/rda.13544. Epub 2019 Aug 23.
This study investigated the influence of heat shock during in vitro maturation on embryo development following in vitro fertilization (IVF) or parthenogenesis (Part). Immature bovine cumulus-oocyte complexes were exposed to heat shock (41.0°C) during the first 12 hr of in vitro maturation (IVM), followed by 12 hr at 38.5°C. Control group consisted of in vitro maturation for 24 hr at 38.5°C. Oocytes were in vitro-fertilized or activated with ionomycin and cultured in vitro for 192 hr post-in vitro insemination or parthenogenetic activation (hpia). There was an interaction (p < .01) between temperature of IVM and method of oocyte activation (IVF or Part) for cleavage at 48 hpia. Heat shock had a negative impact (p < .01) on cleavage of IVF embryos, whereas no (p > .05) effect was found in the Part embryos. Embryo development towards blastocyst stage at 168 and 192 hpia decreased in both IVF and Part embryos derived from heat-shocked oocytes. Heat shock increased (p < .05) the apoptotic index in Part blastocysts, but no effect (p > .05) was found in IVF counterparts. Heat shock also down-regulated the expression of AQP3 (p < .01) and up-regulated the expression of HSP70.1 (p < .01) in Part blastocysts, whereas it down-regulated the expression of ATP1A1 (p < .05) in IVF blastocysts. In conclusion, the effects of heat shock during IVM on early embryo cleavage and blastocyst apoptosis are influenced by the method of oocyte activation and expression of some genes can be disturbed in embryos derived from heat-shocked oocytes.
本研究调查了体外成熟过程中的热休克对体外受精（IVF）或孤雌生殖（Part）后胚胎发育的影响。未成熟牛卵丘-卵母细胞复合体在体外成熟（IVM）的前12小时暴露于热休克（41.0°C），随后在38.5°C下培养12小时。对照组在38.5°C下进行24小时体外成熟。卵母细胞进行体外受精或用离子霉素激活，并在体外受精或孤雌激活（hpia）后体外培养192小时。在48 hpia时，IVM温度与卵母细胞激活方法（IVF或Part）之间存在相互作用（p <.01），对卵裂有影响。热休克对IVF胚胎的卵裂有负面影响（p <.01），而在Part胚胎中未发现影响（p >.05）。来自热休克卵母细胞的IVF和Part胚胎在168和192 hpia时向囊胚阶段的胚胎发育均减少。热休克增加了（p <.05）Part囊胚中的凋亡指数，但在IVF囊胚中未发现影响（p >.05）。热休克还下调了Part囊胚中AQP3的表达（p <.01）并上调了HSP70.1的表达（p <.01），而在IVF囊胚中下调了ATP1A1的表达（p <.05）。总之，IVM期间热休克对早期胚胎卵裂和囊胚凋亡的影响受卵母细胞激活方法的影响，并且热休克卵母细胞来源的胚胎中一些基因的表达可能受到干扰。
