Overview of the Effects of Moringa oleifera Leaf Extract on Oxidative Stress and Male Infertility: A Review

Abstract

According to a recent report by the WHO, 50–80 million people suffer with infertility. Amongst these populations, male counterparts account for 20–50% of infertility cases. The aetiology of infertility in men includes many factors such as psychological issues, lifestyle and environmental factors, hormonal disorders and chromosomal abnormalities. The pathophysiology of these aetiologies may be initiated by a local inflammatory reaction increasing reactive oxygen species (ROS) production, which can negatively affect the male reproductive system by altering the hypothalamic–pituitary–gonadotropin axis (HPG axis). Alteration of the HPG axis may affect testicular steroidogenesis, spermatogenesis, the Leydig cells and Sertoli cells, leading to poor semen quality. The prevalence of male infertility underscores the need for a thorough scientific investigation to identify treatable or reversible factors using plant adjuvants with antioxidative properties. Therefore, this review aims to provide an overview of the currently available knowledge on the aetiologies of male reproductive dysfunction, emphasising infertility risk factors, as well as elucidating the possible ways by which readily available alternatives, such as Moringa oleifera leaves, may mitigate male infertility by highlighting its role on the oxidative stress parameters, reproductive hormonal levels, testicular steroidogenesis and spermatogenesis, gene expression, weight and morphology of the testis and sperm parameters.