Involvement of mitochondrial activity in mediating ELF‐EMF stimulatory effect on human sperm motility

Abstract

It has recently been reported that the exposure of human spermatozoa to an extremely low frequency (ELF) electromagnetic field (EMF) with a square waveform of 5 mT amplitude and frequency of 50 Hz improves sperm motility. The functional relationship between the energy metabolism and the enhancement of human sperm motility induced by ELF-EMF was investigated. Sperm exposure to ELF-EMF resulted in a progressive and significant increase of mitochondrial membrane potential and levels of ATP, ADP and NAD(+) that was associated with a progressive and significant increase in the sperm kinematic parameters. No significant effects were detected on other parameters such as ATP/ADP ratio and energy charge. When carbamoyl cyanide m-chlorophenylhydrazone (CICCP) was applied to inhibit the oxidative phosphorylation in the mitochondria, the values of energy parameters and motility in the sperm incubated in the presence of glucose and exposed to ELF-EMF did not change, thus indicating that the glycolysis was not involved in mediating ELF-EMF stimulatory effect on motility. By contrast, when pyruvate and lactate were provided instead of glucose, the energy status and motility increased significantly in ELF-EMF-treated sperm. Under these culture conditions, the inhibition of glycolitic metabolism by 2-deoxy-D-glucose (DOG) again resulted in increased values of energy and kinematic parameters, indicating that gluconeogenesis was not involved in producing glucose for use in glycolysis. We concluded that the key role in mediating the stimulatory effects exerted by ELF-EMF on human sperm motility is played by mitochondrial oxidative phosphorylation rather than glycolysis.

Effects of intermediate frequency magnetic fields on male fertility indicators in mice

“…These higher frequencies might be responsible for the motility-stimulating effect of the square wave. Understanding of the mechanisms of the regulation of sperm motility is limited, but motion naturally needs energy, and reported evidence indicates that mitochondrial oxidative phosphorylation has a key role in mediating the effect of 50-Hz square wave MF on sperm motility (Turner, 2006, Iorio et al, 2011). …”

Proteomic analysis and microtubule dynamicity of human sperm in electromagnetic cryopreservation

“…Therefore, optimizing the cryopreservation procedure to reduce the concentration of ROS can be efficient for the preservation of microtubules in sperm during the freeze‐thaw process. Recently, earlier studies reported the beneficial effects of the extremely low electromagnetic field (ELEF) on the cryopreservation process of the sperm . The ELEF affects the physicochemical properties of water including the inhibition of ice nucleation at the higher degrees of supercooling, the production of small ice crystals throughout the frozen product, and the prevention of the cell destruction .…”

Evaluations of the Effects of Extremely Low-Frequency Electromagnetic Fields on Growth and Antibiotic Susceptibility ofEscherichia coliandPseudomonas aeruginosa

“…In latest years, several studies have been performed to verify direct effects exerted by ELF-EMF on cell functions. Although results have been somewhat controversial, a variety of cell responses have been observed involving proliferation and differentiation [1–10], gene expression [11–14], modulation of the membrane receptors functionality [15–20], apoptosis [21–23], alteration in ion homeostasis [1, 6, 13, 24–26], and free radicals generation [25, 27–30]. …”