Impact of Oxidative Stress on Male Reproduction: Amelioration by Melatonin and Some Selected Food-Grade Antioxidants

Abstract

Infertility is a common issue. In India, it has doubled in prevalence, raising health issues in both individuals and communities. Couples who are infertile suffer emotionally, socially, and financially. The Indian Society of Assisted Reproduction estimates that there are up to 27.5 million infertile persons living in India, both men and women. Endocrine disruptors, environmental stress, and abnormalities/imbalances in the body’s natural antioxidant defence mechanism all put male fertility at greater risk. Studies on how high altitude affects male fertility are very few. Recent research has shown that oxidative stress from different sources impairs spermatogenesis and causes an imbalance in the level of male hormones. There are two primary causes of oxidative stress: extrinsic and intrinsic, responsible for free-radical generation. There is an internal antioxidant defence mechanism that scavenges the reactive oxygen species, i.e., free radical generation which neutralizes oxidative stress. These antioxidants are important for the protection of cellular integrity. Apart from the antioxidants, various food supplements like melatonin, vitamin C, vitamin E, carotenoids, cysteines, etc., are suitable antioxidants for improving male fertility. Therefore, there is a great need for information on some clinically examined edible phytooxidants, including melatonin, for amelioration of oxidative stress-induced male infertility. This review focuses on the information available as of now about free radical (ROS)-induced reproductive damages in the plains and the high-altitude regions and the role of various antioxidants, including melatonin, in male infertility.