Mitochondrial Functionality and Chemical Compound Action on Sperm Function

Abstract

During the last decade, several studies have shown that mitochondrial parameters, such as integrity, respiratory activity, membrane potential and ROS production are intimately linked with sperm quality. Given the limitations of conventional semen analyses in terms of predicting male fertility, an increasing number of studies are focusing on the characterization of sperm mitochondria in order to more accurately assess sperm functionality. Moreover, mitochondria from several organs, such as the liver, have been described as a powerful screening tool for drug safety, being an easy in vitro model to assess the toxicity of distinct families of compounds. Given that mitochondrial functionality is intimately related to sperm homeostasis, it has become important to understand how compounds, ranging from dietary supplements, environmental pollutants, dependency-inducing drugs to pharmacological agents (such as erectile dysfunction-targeted drugs and male contraceptives) affect sperm mitochondrial function. In this review, we discuss studies describing the effects of various chemical agents on spermatozoa, with particular emphasis on mitochondrial function. From the extensive literature analyzed, we conclude that in some cases the role of sperm mitochondria as putative predictors of sperm functionality is very obvious, while in others further studies are needed to clarify this issue.

Incubation of human sperm with micelles made from glycerophospholipid mixtures increases sperm motility and resistance to oxidative stress

“…Since the viability and motility of sperm are related to the health of their mitochondria [ 95 , 96 ], and because we have observed incorporation of GPL in regions of sperm where mitochondria are abundant, we sought to determine if these effects are correlated with mitochondrial function. Moreover, most of the ROS/RNS damage in sperm is linked to mitochondrial dysfunction.…”

“…Mitochondria and glycolysis are the main sources of energy production needed for sperm motility. Mitochondria are also one of the main sources of ROS involved in sperm oxidative stress [ 96 , 144 , 153 ]. Excessive ROS production in the mitochondria impacts sperm on many cell levels, among them are damage to lipids in the plasma membrane and mitochondrial membranes, resulting in loss of MIMP [ 154 , 155 ].…”

Autophagy is increased in cryptorchid testis resulting in abnormal spermatozoa

“…Remarkably, ROS is known to activate autophagy in vitro 50. ROS have a pathological effect on male gametes resulting in apoptosis-like phenomenon 4951. Swollen mitochondria are one of the hallmarks of early apoptosis stages in cells,52 and the disruption of mitochondrial membrane facilitates the release of cytochrome c in cell cytoplasm triggering intrinsic mitochondria-mediated apoptosis 53…”

In vivo analysis of Bisphenol A induced dose-dependent adverse effects in cauda epididymis of mice

“…The effect was comparatively more pronounced in high-dose bisphenol A-treated group than with a low dose. These results indicate that the onset of cytotoxicity caused by BPA may depend on the intracellular energy status and that mitochondria are important targets of the compound (Amaral et al, 2016). The toxicity caused by inhibition of ATP synthesis may be related to the concentration of unmetabolized free BPA remaining in the cell suspensions.…”