Department of Life Science and Bioinformatics, Assam University, Silchar, India.
Adv Exp Med Biol. 2022;1358:9-40. doi: 10.1007/978-3-030-89340-8_2.
Reactive oxygen species (ROS) are oxygen-containing molecules which are reactive in nature and are capable of independent existence in the body. ROS comprise mostly of free radicals that contain at least one unpaired electron. Endogenous sources are the foremost birthplaces of ROS, which include mitochondrial electron transport chain, endoplasmic reticulum and peroxisome. Conversely, numerous enzymatic pathways such as xanthine oxidase and cyclooxygenase systems are among the prominent generators of cellular ROS. Major sources of ROS in the female reproductive tract include Graafian follicles, follicular fluid, fallopian tube, peritoneal cavity and endometrium. On the contrary, leukocytes, immature spermatozoa and varicocele are the key originators of ROS in the male reproductive system. For the sake of maintaining a proper oxidative balance, cells have evolved a variety of antioxidative molecules. From the physiological perspective, ROS and antioxidants are actively involved in the regulation of myriad female reproductive processes, such as cyclic luteal and endometrial changes, follicular development, ovulation, fertilization, embryonic implantation, maintenance of pregnancy and parturition. Similarly, physiological amounts of ROS are crucial in the accomplishment of various male reproductive functions as well, which include spermatozoa maturation, capacitation, hyperactivation and acrosome reaction. This chapter highlights the birthplaces of ROS in the female and male reproductive tract along with mechanisms of their production. This chapter will also put forward specific physiological roles of these reactive molecules in upholding the structural integrity and functionality of both the reproductive systems.
活性氧（ROS）是一类含氧的分子，具有反应活性，能够在体内独立存在。ROS 主要由自由基组成，自由基至少含有一个不成对的电子。内源性来源是 ROS 的首要发源地，包括线粒体电子传递链、内质网和过氧化物酶体。相反，许多酶促途径，如黄嘌呤氧化酶和环氧化酶系统，是细胞 ROS 的主要生成者。女性生殖道中 ROS 的主要来源包括格拉夫卵泡、卵泡液、输卵管、腹腔和子宫内膜。相反，白细胞、未成熟的精子和精索静脉曲张是男性生殖系统中 ROS 的主要来源。为了维持适当的氧化还原平衡，细胞已经进化出多种抗氧化分子。从生理角度来看，ROS 和抗氧化剂积极参与调节许多女性生殖过程，如周期性黄体和子宫内膜变化、卵泡发育、排卵、受精、胚胎着床、妊娠维持和分娩。同样，生理量的 ROS 对完成各种男性生殖功能也至关重要，包括精子成熟、获能、超激活和顶体反应。本章重点介绍女性和男性生殖道中 ROS 的发源地以及它们产生的机制。本章还将提出这些反应性分子在维持生殖系统结构完整性和功能方面的具体生理作用。
