Reproductive Dysfunction and Testicular Epigenetic Alterations in Male Rats with Experimental Amebiasis: Evaluation of SPATA6 Methylation and Therapeutic Outcomes.

DNA methylation is a key epigenetic mechanism regulating gene expression during spermatogenesis. This study investigated the effects of experimental amebiasis induced by Entamoeba histolytica and its treatment with metronidazole (MTZ) on the methylation status of the Spermatogenesis Associated 6 (SPATA6) gene and male reproductive function. Twenty-four adult male rats were assigned to control, infected, and MTZ-treated groups. Following treatment, testicular tissues were analyzed for SPATA6 promoter methylation via bisulfite sequencing, infection confirmation by PCR, histopathological changes by hematoxylin and eosin (H&E) staining, Inhibin B and Androgen-Binding Protein (ABP) expression by immunohistochemistry, and sperm quality indices. The infected group exhibited distinct non-CpG methylation at a SPATA6 locus, confirmed reproductive tract infection, severe testicular damage, increased expression of Inhibin B and ABP, and significantly impaired sperm parameters. MTZ treatment successfully cleared the parasite and partially restored testicular architecture and sperm count; however, residual abnormalities in sperm motility, histology, and SPATA6 methylation persisted. While these findings suggest that parasitic infection and its treatment may induce epigenetic dysregulation in the testis, the direct functional link between the observed methylation change and reproductive outcomes remains inconclusive due to the limited scope of analysis. These results underscore the need for genome-wide methylation and transcriptomic profiling to better characterize the molecular basis of infection- and treatment-related reproductive effects. The study provides initial insights into infection-associated epigenetic modulation in male reproduction, with potential implications for fertility and reproductive health.