Involvement of metabolic pathway in the sperm spontaneous acrosome reaction
Involvement of metabolic pathway in the sperm spontaneous acrosome reaction
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DOI：
10.1016/j.theriogenology.2022.08.018
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发表时间：
2022-08-28
期刊：
影响因子：
2.8
通讯作者：
Breitbart, Haim
中科院分区：
文献类型：
--
作者：
Dahan, Tsipora;Breitbart, Haim
为了使卵子受精，精子必须在雌性生殖道中经历一系列生化过程，统称为获能。只有有能力的精子才能与卵子相互作用，导致顶体反应（AR），使卵子穿透和受精。精子在到达卵子之前可以进行自发AR (sAR)，从而阻止成功受精。本研究研究了精子获能和sAR的代谢途径。糖酵解或氧化磷酸化的抑制不影响获能或sAR水平；然而，当这两个系统被抑制时，没有发生获能，sAR显著增加。在这种atp饥饿下，sAR的增加是由Ca2+通过CatSper阳离子通道流入精子引起的。蛋白激酶A （PKA）是精子获能过程中必不可少的关键酶；当单一代谢系统被抑制时，其活性没有变化，而当两个代谢系统被抑制时，其活性被完全抑制。蛋白酪氨酸磷酸化（PTP）也发生在精子获能过程中，当一个代谢系统受到抑制时，PTP被部分降低，当两个代谢系统受到抑制时，PTP被完全阻断。我们得出结论，ATP， PKA和PTP参与了保护精子免受sAR的机制。(C) 2022 Elsevier Inc.。版权所有。
In order to fertilize the egg, spermatozoa must undergo a series of biochemical processes in the female reproductive tract collectively called capacitation. Only capacitated sperm can interact with the egg resulting in the acrosome reaction (AR), allowing egg penetration and fertilization. Sperm can undergo spontaneous AR (sAR) before reaching the egg, preventing successful fertilization. Here we investigated the metabolic pathways involved in sperm capacitation and sAR. Inhibition of glycolysis or oxidative phosphorylation did not affect capacitation or sAR levels; however, when both systems were inhibited, no capacitation occurred, and there was a significant increase in sAR. Under such ATP-starvation, the increase in sAR is triggered by Ca2+ influx into the sperm via the CatSper cation channel. Protein kinase A (PKA) is an essential key enzyme in sperm capacitation; there was no change in its activity when a single metabolic system was inhibited, while complete inhibition of was observed when the two systems were inhibited. Protein tyrosine phosphorylation (PTP), also known to occur in sperm capacitation, was partially reduced by inhibition of one metabolic system, and completely blocked when the two metabolic systems were inhibited. We conclude that ATP, PKA and PTP are involved in the mechanisms protecting sperm from sAR. (C) 2022 Elsevier Inc. All rights reserved.