猪通常通过人工授精繁殖,液体精液保存在15-20℃。虽然这种保存方法带来了许多好处,包括与冻融精子相比更高的生殖性能,储存期是一个限制因素。由于线粒体调节精子生理的许多方面,调节其活性可能会对其寿命产生影响。与这个假设一致,本研究试图调查是否抑制电压依赖性阴离子通道(VDAC),它位于线粒体外膜,调节线粒体和体细胞中细胞质之间的离子流,影响猪精子在17°C下液体保存的恢复力。为此,用两种不同浓度的TRO19622(5μM和50μM)处理精液样品(N=7),VDAC的抑制剂,并在17°C下储存10天。在第0、4和10天,通过流式细胞术和计算机辅助精子分析(CASA)评估精子质量和功能参数。抑制VDAC的效果取决于抑制剂的浓度。一方面,最大浓度的TRO19622(50μM)导致精子活力下降,活力和线粒体膜电位,这可能与观察到的细胞内Ca2+增加有关。相比之下,用5μMTRO19622处理的样品的总精子运动性高于对照组,这表明,当VDACs通道被最低浓度的阻断剂抑制时,猪精子对液体储存的恢复能力增加。总之,目前的研究表明线粒体功能,如受线粒体外膜离子通道如VDAC的调节,与精子对液体保存的恢复力有关,并可能影响细胞寿命。
Pigs are usually bred through artificial insemination with liquid semen preserved at 15-20 °C. While this method of preservation brings many benefits, including a greater reproductive performance compared to frozen-thawed sperm, the period of storage is a limiting factor. As the mitochondrion regulates many facets of sperm physiology, modulating its activity could have an impact on their lifespan. Aligned with this hypothesis, the present study sought to investigate whether inhibition of voltage-dependent anion channels (VDACs), which reside in the outer mitochondrial membrane and regulate the flux of ions between mitochondria and the cytosol in somatic cells, influences the resilience of pig sperm to liquid preservation at 17 °C. For this purpose, semen samples (N = 7) were treated with two different concentrations of TRO19622 (5 μM and 50 μM), an inhibitor of VDACs, and stored at 17 °C for 10 days. At days 0, 4 and 10, sperm quality and functionality parameters were evaluated by flow cytometry and computer-assisted sperm analysis (CASA). The effects of inhibiting VDACs depended on the concentration of the inhibitor. On the one hand, the greatest concentration of TRO19622 (50 μM) led to a decrease in sperm motility, viability and mitochondrial membrane potential, which could be related to the observed intracellular Ca2+ increase. In contrast, total sperm motility was higher in samples treated with 5 μM TRO19622 than in the control, suggesting that when VDACs channels are inhibited by the lowest concentration of the blocking agent the resilience of pig sperm to liquid storage increases. In conclusion, the current research indicates that mitochondrial function, as regulated by ion channels in the outer mitochondrial membrane like VDACs, is related to the sperm resilience to liquid preservation and may influence cell lifespan.