Andrological Unit, Dermatology, Venerology and Allergology Clinic, University Hospital Leipzig, Leipzig, Germany.
Institute for Medical Physics and Biophysics, Universität Leipzig, Leipzig, Germany.
Andrology. 2018 Mar;6(2):335-344. doi: 10.1111/andr.12467. Epub 2018 Feb 13.
To study apoptosis as a functional pathway in mature spermatozoa and apoptosis correlated to the acrosome reaction via the intracellular calcium concentration, semen samples from 27 healthy human donors were treated with inducers of apoptosis (betulinic acid, thapsigargin), inducers of the acrosome reaction (thapsigargin, calcium ionophore) or hydrogen peroxide to produce reactive oxygen species with and without prior incubation with a calcium chelator. Computer-assisted sperm analysis, flow cytometry, and transmission electron microscopy were performed to analyze changes in the acrosomal status and in apoptotic features. Betulinic acid, thapsigargin, and the calcium ionophore treatment resulted in an increased number of sperm cells with caspase 9 and caspase 3 activation, disrupted mitochondrial membrane potential, and a reacted acrosome. Sperm motility was decreased in all cases. Transmission electron analyses showed ultra-morphological changes, such as membrane integrity, membrane blebbing, the formation of head vacuoles, defects of the nuclear envelope, nuclear fragmentation, and the acrosome reaction. Acrosome reaction and apoptotic features decreased due to the reduction in intracellular calcium by the calcium chelator NP-EGTA, AM. Therefore, apoptotic cell death in acrosome-reacted sperm cells mediated by high intracellular calcium levels is possible.
为了研究成熟精子细胞中的细胞凋亡作为一种功能途径，以及通过细胞内钙离子浓度与顶体反应相关的细胞凋亡，对 27 名健康人类供体的精液样本进行了凋亡诱导剂（白桦脂酸、他普西醇）、顶体反应诱导剂（他普西醇、钙离子载体）或过氧化氢的处理，以产生具有和不具有钙螯合剂预先孵育的活性氧。通过计算机辅助精子分析、流式细胞术和透射电子显微镜分析顶体状态和凋亡特征的变化。白桦脂酸、他普西醇和钙离子载体处理导致具有半胱天冬酶 9 和半胱天冬酶 3 激活、线粒体膜电位破坏以及顶体反应的精子细胞数量增加。在所有情况下，精子运动能力均下降。透射电镜分析显示超形态变化，如膜完整性、膜起泡、头部空泡形成、核膜缺陷、核碎裂和顶体反应。钙离子螯合剂 NP-EGTA、AM 通过减少细胞内钙离子，顶体反应和凋亡特征减少。因此，高细胞内钙离子水平介导的顶体反应精子细胞中的细胞凋亡性死亡是可能的。
