PDF(Pubmed)
Abstract：
The preservation of liquid semen is pivotal for both industrial livestock production and genetic management/conservation of species with sperm that are not highly cryo-tolerant. Nevertheless, with regard to poultry semen, even brief in vitro storage periods can lead to a notable decline in fertility, despite the in vivo capacity to maintain fertility for several weeks when within the hen\'s sperm storage tubules. For fertility in sperm, intracellular calcium ions ([Ca2+]i) play a key role in signaling towards modifying energy metabolism. While reducing [Ca2+]i has been found to enhance the preservation of sperm fertility in some mammals, the connection between semen fertility and calcium availability in avian sperm has received limited attention. In this study, we demonstrate that the use of extracellular and intracellular calcium chelators in liquid semen extenders, specifically EGTA and EGTA-AM, has distinct effects on prolonging the fertility of chicken sperm. These results were validated through in vivo fertility tests. Mechanistically, the effects observed were linked to coordination of mitochondrial metabolism and ATP catabolism. Despite both calcium chelators inducing hypoxia, they differentially regulated mitochondrial respiration and ATP accumulation. This regulation was closely linked to a bimodal control of dynein ATPase activity; a direct initial activation with reduction in [Ca2+]i, and subsequent suppression by cytoplasmic acidification caused by lactic acid. These findings not only contribute to advancing poultry liquid semen preservation techniques, but also elucidates biologically relevant mechanisms that may underlie storage within the female reproductive tract in birds.
摘要：
液体精液的保存对于工业牲畜生产和具有不具有高度耐低温性的精子的物种的遗传管理/保护至关重要。然而，关于家禽精液，即使是短暂的体外储存时间也会导致生育能力的显著下降，尽管在体内有能力维持几个星期的生育能力，但在母鸡的精子储存小管内。为了精子的生育能力，细胞内钙离子（[Ca2]i）在改变能量代谢的信号传导中起关键作用。虽然已发现减少[Ca2]i可以增强某些哺乳动物的精子生育能力，精液生育力与禽类精子中钙的利用率之间的联系受到了有限的关注。在这项研究中,我们证明了在液体精液补充剂中使用细胞外和细胞内钙螯合剂，特别是EGTA和EGTA-AM，对延长鸡精子的生育力有明显的影响。这些结果通过体内生育力测试得到了验证。机械上,观察到的效应与线粒体代谢和ATP分解代谢的协调有关.尽管两种钙螯合剂都能诱导缺氧，它们差异调节线粒体呼吸和ATP积累。这种调节与动力蛋白ATPase活性的双峰控制密切相关；[Ca2]i减少的直接初始激活，以及随后由乳酸引起的细胞质酸化的抑制。这些发现不仅有助于推进家禽液体精液保存技术，而且还阐明了可能在鸟类雌性生殖道内储存的生物学相关机制。
