Kopa Zsolt, Keszthelyi Marton, Sofikitis Nikolaos
Andrology Centre, Department of Urology, Semmelweis University, Budapest, Hungary.
Department of Urology, Ioannina University School of Medicine, Ioannina, Greece.
Curr Pharm Des. 2021;27(23):2665-2668. doi: 10.2174/1381612826666200303115552.
Reactive Oxygen Species (ROS) are required for intact spermatogenesis and sperm function, but excessive levels will cause oxidative stress, impairing sperms and sperm function due to membrane damage and DNA fragmentation.
Theoretically, antioxidant supplementation may act as a protection system against free radicals. Since infertile males have higher levels of ROS, nutritional supplements are widely used for protecting sperms. In the recent review, the authors summarize the most recent data regarding the effect of antioxidant treatment and draw the attention of the limitations of antioxidant use in male infertility.
The recent review gives an update of antioxidant treatment in male infertility.
Improvement of sperm parameters was reported in the majority of studies. Comparing different antioxidants versus placebo showed low certainty of evidence with a serious risk of bias, and there is a lack regarding certain doses, pregnancy rate, and live birth rate outcomes. Various clinical studies and randomized control trials reported negative outcomes. Conflicting findings lead the attention to the study of biochemical features of the oxidant vs. antioxidant equilibrium. Higher exposure to antioxidants will result in "reductive stress", which has harmful effects on sperm function, moreover can negatively influence embryo development. Reductive stress is as dangerous as oxidative stress and may act as a cause of different human pathologies.
An intact balance of oxidant and antioxidant systems is required for normal sperm function. No guideline exists for the antioxidant dose regimen and treatment duration. Overdosing can result in reductive stress, which is also harmful to fertility and can cause several diseases. Assessment of the pre-treatment redox status can be recommended before the administration of exogenous antioxidants.
完整的精子发生和精子功能需要活性氧（ROS），但过量的ROS会导致氧化应激，由于膜损伤和DNA片段化而损害精子和精子功能。
从理论上讲，补充抗氧化剂可能作为一种针对自由基的保护系统。由于不育男性的ROS水平较高，营养补充剂被广泛用于保护精子。在最近的综述中，作者总结了有关抗氧化剂治疗效果的最新数据，并提请注意抗氧化剂在男性不育症中使用的局限性。
最近的综述提供了男性不育症抗氧化剂治疗的最新情况。
大多数研究报告了精子参数的改善。将不同的抗氧化剂与安慰剂进行比较，证据的确定性较低，存在严重的偏倚风险，并且在某些剂量、妊娠率和活产率结果方面存在不足。各种临床研究和随机对照试验报告了负面结果。相互矛盾的研究结果促使人们关注氧化剂与抗氧化剂平衡的生化特征研究。更高水平地接触抗氧化剂会导致“还原应激”，这对精子功能有有害影响，而且会对胚胎发育产生负面影响。还原应激与氧化应激一样危险，可能是不同人类疾病的一个原因。
正常的精子功能需要氧化剂和抗氧化剂系统的完整平衡。目前尚无关于抗氧化剂剂量方案和治疗持续时间的指南。过量用药会导致还原应激，这对生育能力也有害，并可能引发多种疾病。在给予外源性抗氧化剂之前，建议评估治疗前的氧化还原状态。
