玉米赤霉烯酮致大鼠睾丸支持细胞DNA损伤的研究

Study on DNA damage of sertoli cell in rat induced by zearalenone

以大鼠原代睾丸支持细胞为材料，用0（对照组）、5、10、20μmol／L的玉米赤霉烯酮（ZEA）进行染毒。24h后，通过彗星试验观、免疫荧光试验、Western—blot等方法检测ZEA对细胞DNA及相关蛋白表达的影响。结果显示，随着ZEA浓度的增加，DNA彗星样拖尾现象逐渐明显，与对照组比较，10μmol／L和20μmol／LZEA剂量组的细胞的彗星拖尾尾长、尾部DNA含量比例和尾矩均有极显著差异（P〈0．01）；10μmol／L和20μmol／LZEA剂量组γ—H2AX焦点数量均较对照组有极显著差异（P〈0．01）；各染毒组γ-H2AX、P53、P21等蛋白的表达水平均较对照组有显著或极显著差异（P〈0．05或P〈0．01）。结果表明。ZEA能致大鼠睾丸支持细胞DNA损伤。这一过程能激活P—ATM—P53-P21信号通路，促使细胞发生生长阻滞并抑制其增殖。

The sertoli cells of primary rat testis were used as materials treated with 0（control group）,5,10 and 20 μmol/L gEA,respectively,for 24 h. The effects of ZEA on the expression of DNA and related proteins were detected by comet assay,immunofluorescence assay and Western-blot. With the increase of the concentration of ZEA,the results showed that the phenomenon of comet trailing became more and more obvious. The tail length,tail DNA content ratio and tail moment of comet cells in 10 μmol/L and 20 μmol/L ZEA groups were significantly different from those in control group（P〈0.01）,and the number of T-H2AX foci in 10 μmol/L and 20μmol/L ZEA groups was significantly different from that in control group（P〈0.01）,and T-H2AX content ratio and tail moment in 10μmol/L and 20 μmol/L gEAgroups were significantly different from those in control group（P〈0. 01）. The expression levels ofp53,P21 and other proteins were significantly higher than those in the control group（P〈0.05 or P〈0.01）.In conclusion, ZEA could induce DNAdamage in sertoli cells and this process could activate the P-ATM→P53→P21 signaling pathway,induce growth arrest of sertoli cells and inhibit the proliferation of sertoli cells.