Male pronucleus formation after ICSI: effect of oocyte cysteine or sperm Triton X-100 treatments
Male pronucleus formation after ICSI: effect of oocyte cysteine or sperm Triton X-100 treatments
复制标题
DOI：
10.17221/8237-cjas
复制
发表时间：
2015-01-01
影响因子：
1.2
通讯作者：
Garcia-Rosello, E.
中科院分区：
文献类型：
--
作者：
Garcia-Mengual, E.;Silvestre, M. A.;Garcia-Rosello, E.
在猪中，卵胞浆内单精子注射（ICSI）的效率仍然很差。精子染色质的不充分解凝聚，其转化为雄性原核（MPN）以及随后的不能激活卵母细胞，似乎是ICSI效率低的主要原因。为了改善MPN的形成，我们采取了两种不同的方法。一方面，ICSI后的体外培养（IVC）培养基补充有1.71mM半胱氨酸（CYS）。或者，在ICSI之前用Triton X-100（TX）消化精子膜，以改善精子染色质对卵母细胞细胞质的暴露。ICSI后6h，TX组激活率（70.0%）显著高于CYS组（42.2%）和对照组（48.9%）（P <0.05）。然而，在原核数量、2PN（卵母细胞有2个原核且无可见精子）和1PN+精子（卵母细胞有1个原核和1个精子头）方面，未观察到3组之间的显著差异。ICSI后22小时，TX、CYS和对照组的激活率相似（分别为73.1%、78.9%和75.7%）。此外，我们未观察到TX、CYS和对照组之间原核数量、2PN（分别为52.6、56.7和50%）或1PN+精子（分别为21.1、33.3和32.1%）的显著差异。虽然在CYS组中未观察到卵裂，但在对照组（21.3%）和TX组（10.5%）之间未观察到卵裂率的显著差异。总之，在我们的条件下，无论是CYS补充，也没有精子TX预处理能够改善MPN形成后6和22小时ICSI。然而，精子TX预处理在ICSI后6小时改善了卵母细胞活化，尽管ICSI后22小时这种有益效果并不持续。
In pigs, intracytoplasmic sperm injection (ICSI) efficiency is still poor. The inadequate decondensation of the sperm chromatin, its transformation into the male pronucleus (MPN) together with the subsequent inability to activate the oocyte, seem to be the main causes of the low ICSI efficiency. In order to improve the MPN formation we took two different approaches. On the one hand, the in vitro culture (IVC) medium postICSI was supplemented with 1.71mM cysteine (CYS). Alternatively, the sperm membrane was digested with Triton X-100 (TX) before ICSI, to improve the exposure of the sperm chromatin to the oocyte cytoplasm. After 6 h post-ICSI, the activation rate was significantly higher in TX group (70.0%) compared with CYS and control groups (42.2% and 48.9%, respectively; P < 0.05). However, no significant differences between the three groups were observed in terms of the number of pronuclei, 2PN (oocytes with 2 pronuclei and no visible sperm), and 1PN + sperm (oocytes with 1 pronucleus and one sperm head). At 22 h post-ICSI, the activation rates were similar in TX, CYS, and control groups (73.1, 78.9, and 75.7%, respectively). In addition, we did not observe significant differences between TX, CYS, and control groups for the number of pronuclei, 2PN (52.6, 56.7, and 50%, respectively) or 1PN + sperm (21.1, 33.3, and 32.1%, respectively). While no cleavage was observed in the CYS group, no significant differences in the cleavage rate were observed between control (21.3%) and TX (10.5%) groups. In summary, and under our conditions, neither CYS supplement, nor sperm TX pre-treatment were able to improve MPN formation at 6 and 22 h post-ICSI. However, the sperm TX pre-treatment improved oocyte activation at 6 h post-ICSI, although 22 h post-ICSI such a beneficial effect did not persist.