CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Portugal; Department of Life Sciences, University of Coimbra, Portugal.
Mol Cell Endocrinol. 2013 Oct 15;379(1-2):74-84. doi: 10.1016/j.mce.2013.06.005. Epub 2013 Jun 13.
Mitochondria are cellular organelles with crucial roles in ATP synthesis, metabolic integration, reactive oxygen species (ROS) synthesis and management, the regulation of apoptosis (namely via the intrinsic pathway), among many others. Additionally, mitochondria in different organs or cell types may have distinct properties that can decisively influence functional analysis. In terms of the importance of mitochondria in mammalian reproduction, and although there are species-specific differences, these aspects involve both energetic considerations for gametogenesis and fertilization, control of apoptosis to ensure the proper production of viable gametes, and ROS signaling, as well as other emerging aspects. Crucially, mitochondria are the starting point for steroid hormone biosynthesis, given that the conversion of cholesterol to pregnenolone (a common precursor for all steroid hormones) takes place via the activity of the cytochrome P450 side-chain cleavage enzyme (P450scc) on the inner mitochondrial membrane. Furthermore, mitochondrial activity in reproduction has to be considered in accordance with the very distinct strategies for gamete production in the male and female. These include distinct gonad morpho-physiologies, different types of steroids that are more prevalent (testosterone, estrogens, progesterone), and, importantly, the very particular timings of gametogenesis. While spermatogenesis is complete and continuous since puberty, producing a seemingly inexhaustible pool of gametes in a fixed environment; oogenesis involves the episodic production of very few gametes in an environment that changes cyclically. These aspects have always to be taken into account when considering the roles of any common element in mammalian reproduction.
线粒体是细胞细胞器，在 ATP 合成、代谢整合、活性氧（ROS）合成和管理、细胞凋亡（即通过内在途径）调节等方面发挥着关键作用。此外，不同器官或细胞类型的线粒体可能具有不同的特性，这些特性可以决定其功能分析。就线粒体在哺乳动物生殖中的重要性而言，尽管存在物种特异性差异，但这些方面涉及配子发生和受精的能量考虑因素、细胞凋亡的控制以确保产生有活力的配子、ROS 信号以及其他新兴方面。至关重要的是，线粒体是类固醇激素生物合成的起点，因为胆固醇转化为孕烯醇酮（所有类固醇激素的共同前体）是在内质网线粒体膜上通过细胞色素 P450 侧链裂解酶（P450scc）的活性进行的。此外，在考虑生殖中的线粒体活性时，必须根据雄性和雌性中配子发生的非常不同的策略来进行。这些策略包括不同的性腺形态生理学、更常见的不同类型的类固醇（睾酮、雌激素、孕酮），以及非常特殊的配子发生时间。虽然精子发生自青春期以来是完整和连续的，在固定的环境中产生似乎取之不尽的配子池；而卵子发生则涉及在周期性变化的环境中偶尔产生很少的配子。在考虑任何常见元素在哺乳动物生殖中的作用时，这些方面始终都需要考虑。
