Author/Authors :
Taghian Dinani ، Hengameh Institute of Higher Education - Jahad Daneshgahi Learning Institute (ACECR), Isfahan Branch , Naderi ، Nushin Department of Animal Biotechnology - Reproductive Biomedicine Research Center - Royan Institute for Biotechnology , Tavalaee ، Marziyeh Institute of Higher Education - Jahad Daneshgahi Learning Institute (ACECR), Isfahan Branch , Rabiee ، Farzaneh Department of Animal Biotechnology - Cell Science Research Center - Royan Institute for Biotechnology , Nasr-Esfahani ، Mohammad Hossein ACECR Institute of Higher Education - Jahad Daneshgahi Learning Institute (ACECR), Isfahan Branch
Abstract :
Objective: Epigenetic modifications such as DNA methylation play a key role in male infertility etiology. This study aimedto explore the global DNA methylation status in testicular spermatogenic cells of varicocele-induced rats and considertheir semen quality, with a focus on key epigenetic marks, namely 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine(5-hmC), as well as the mRNA and proteins of ten-eleven translocation (TET) methylcytosine dioxygenases 1-3.Materials and Methods: In this experimental study, 24 mature male Wistar rats (8 in each group) were assignedamongst the control, sham, and varicocele groups. Sperm quality was assessed, and DNA methylation patterns oftesticular spermatogenic cells were investigated using reverse transcription-polymerase chain reaction (RT-PCR),western blot, and immunofluorescence techniques.Results: Sperm parameters, chromatin and DNA integrity were significantly lower, and sperm lipid peroxidation significantlyincreased in varicocele-induced rats in comparison with control rats. During spermatogenesis in rat testis, 5-mC and 5-hmCepigenetic marks, and TET1-3 mRNA and proteins were expressed. In contrast to the 5-mC fluorescent signal which waspresented in all testicular cells, the 5-hmC fluorescent signal was presented exclusively in spermatogonia and a few spermatids.In varicocele-induced rats, the 5-mC signal decreased in all cells within the tubules, whereas a strong signal of 5-hmC wasdetected in seminiferous tubules compared to the control group. As well, the levels of TET2 mRNA and protein expressionwere significantly upregulated in varicocele-induced rats in comparison with the control group. Also, our results showed thatthe varicocele-induced animals exhibited strong fluorescent signals of TET1-3 in testicular cells, whereas weak fluorescentsignals were identified in the seminiferous tubules of the control animals.Conclusion: Consequently, we showed TET2 upregulation and the 5-hmC gain at testicular levels are associated withvaricocele and sperm quality decline, and therefore they can be exploited as potential biomarkers of spermatogenesis.
Keywords :
DNA methylation , Male infertility , Sperm , Varicocele , 5 , methylcytosine
