Azar Afshar - Department of Biology and Anatomical Sciences School of Medicine, Shahid Beheshti University of Medical Sciences Tehran, Iran
Fakhroddin Aghajanpour - Department of Biology and Anatomical Sciences School of Medicine, Shahid Beheshti University of Medical Sciences Tehran, Iran
Mohammad-Amin Abdollahifar - Department of Biology and Anatomical Sciences School of Medicine, Shahid Beheshti University of Medical Sciences Tehran, Iran

Spermatogenesis is a complex process that occurs a few degrees below the body temperature; accordingly, spermatogenic cells are extremely heat sensitive. The current study aimed to evaluate the effects of iron oxide nanoparticles loaded by curcumin on spermatogenesis in the scrotal hyperthermia mice model. In this experiment, 18 mice were randomly allocated into the following three groups; Control, Scrotal hyperthermia and Scrotal hyperthermia+ curcumin-loaded iron particles (NPs) (240 μL) (mice were treated for 20 days). Hyperthermia was induced by exposure to the temperature of 43 ° C for 20 minutes every other day for 5 weeks. Afterward, the animals were euthanized; sperm samples were collected for sperm parameters analysis and testis samples were taken for histopathology experiments, evaluation of serum testosterone level and RNA extraction to examine the expression of c-Kit, Stra8 and PCNA genes. Our result indicated that curcumin-loaded iron particles could significantly increase the volume of testis, length of seminiferous tubules, sperm parameters and stereological parameters (i.e. spermatogonia, primary spermatocyte, round spermatid and Leydig cells) thereby increasing serum testosterone level; also, TUNEL positive cells showed a significant decrease in curcumin-loaded iron particles group. Thus, based on the obtained results, the expression of c-Kit, Stra8 and PCNA genes was significantly increased in treatment groups by curcumin-loaded iron particles compared to scrotal hyperthermia induced mice. In conclusion, curcumin-loaded iron particles can be considered an alternative treatment for improving the spermatogenesis process in scrotal hyperthermia induced mice.

Curcumin-loaded iron particles, Spermatogenesis, Long-term scrotal hyperthermia