Effect of duloxetine as antidepressant on TM4 Sertoli cells: Evaluation of Bax and Cx43 gene expression

One of main challenges in worldwide is increasing rate of depression and sexual dysfunction associated with antidepressant drug consumption. Regarding the role of Sertoli cells in spermatogenesis, this study investigated the effect of duloxetine on viability, apoptosis and expression of Bax and Cx43 (Connexin 43) expression in Sertoli cells.

TM4 Sertoli cells were cultured in DMEM/F12 medium containing 2.5% FBS, 5% horse serum and 1% penicillin-streptomycin. Cells were treated with different doses of duloxetine (3.75, 7.5, 15, 30, 60 μg/ml) for 24 to 72 hours. MTT assay was performed to evaluate cell viability. The rate of apoptosis was measured by flow cytometry and RT-qPCR was performed to evaluate of Bax (proapoptotic gene) and Cx43 (essential for spermatogenesis) genes.

Duloxetine reduced cell survival in a dose and time-dependent manner. On the basis of MTT data, IC50 was calculated as 15 μg/ml duloxetine (p≤0.05). TM4 cell apoptosis increased compared to the control group at a dose of 15 μg/ml duloxetine (p≤0.01). RT-qPCR results showed increased expression of Cx43 (p≤0.05) and Bax (p≤0.01) genes under the influence of duloxetine.

Considering the flow cytometry data and the increased expression of Bax, duloxetine may induce apoptosis in Sertoli cells and may be a negative and destructive factor for spermatogenesis process. On the other hand, by increasing the expression level of Cx43 gene, duloxetine increases the molecular communication via gap junctions between Sertoli cells and transmits apoptosis-promoting signals to spermatogenic cells which can influence spermatogenesis quantification.