In vitro toxicity evaluation of melamine on mouse TM4 Sertoli cells

- We demonstrated cytotoxicity of melamine (MA) on the TM4 mouse Sertoli cells (TM4 cells).
- MA suppressed TM4 cell viability.
- MA induced ultrastructural lesions in TM4 cells.
- MA induced cell apoptosis in TM4 cells.
- MA induced down-regulations of junction-associated protein expression in TM4 cells.

The male reproductive toxicity of melamine (MA) has been recognized in recent years excepted for its renal toxicity. Our previous in vivo studies revealed that the damages of Sertoli cell barrier played a critical role in MA-induced testicular toxicity in mice. Herein, we performed an in vitro study to comprehensively evaluate the toxicity of MA on Sertoli cell by examining the influences of MA on the viability, morphology, mortality and intercellular junctions of mouse TM4 Sertoli cells (TM4 cells). The results showed that MA suppressed cell viability, induced obvious ultrastructural changes and cell apoptosis in concentration-dependent manner. Moreover, MA down-regulated the expressions of junction-associated proteins including occludin, N-cadherin, and vimentin, suggesting that MA disrupted the integrity of Sertoli cell barrier. Thus, these results indicated that Sertoli cell might be an important cellular target for MA-induced male reproductive toxicity.