Photobiomodulation restores spermatogenesis in the transient scrotal hyperthermia-induced mice.

Heat stress shock affects the generation of free radicals and can have a harmful effect on spermatogenesis. Photobiomodulation (PBM) is very effective in andrology for treating male infertility. This research aimed at the evaluation of the impacts of PBM on spermatogenesis on the transient scrotal hyperthermia-induced oligospermia mouse model.

This experimental research divided 24 mice into the following four groups: (1) Control, (2) Scrotal hyperthermia, (3) Scrotal hyperthermia receiving laser 0.03 J/cm² for 30 s for each testis, 35 days after induction of scrotal hyperthermia every other day for 35 days, and (4) Scrotal hyperthermia receiving laser 0.03 J/cm² for 30 s for each testis, immediately after induction of scrotal hyperthermia every other day for 35 days. Scrotal hyperthermia was induced by water bath with 43 °C for 30 min. Then, the mice were euthanized, and their sperm samples were collected for sperm parameters analysis. Then, we took the testis samples for histopathological experimentations, serum testosterone level, reactive oxygen species (ROS), RNA extraction for the examination of IL1-α, IL6 and TNF-α genes expression as well as production and glutathione disulfide (GSH) activity.

Our outputs indicated that PBM could largely improve the sperms parameters and stereological parameters, like spermatogonia, primary spermatocyte, round spermatid and Leydig cells together with an increasing level of the serum testosterone and GSH activity compared to the scrotal hyperthermia induced mice. In addition, it was found that the diameter of seminiferous tubules, ROS production, as well as the expression of IL1-α, IL6, and TNF-α genes significantly decreased in the treatment groups by PBM compared to the scrotal hyperthermia induced mice, but there was not a significant difference in terms of testis weight and Sertoli cells between the studied groups.It could be concluded that PBM may be regarded as an alternative treatment for improving the spermatogenesis process in the scrotal hyperthermia induced mice.