玉米赤霉烯酮致睾丸间质细胞毒性作用分子机制的研究

Zearalenone widely exists in mouldy cereals and dairy products. It has reproductive toxicity, immune toxicity and strong cytotoxicity. It is great harm to human and animal health, and can cause serious enconomic losses in breeding industry. Many research showed that zearalenone can reduce the activity of Leydig cells in vitro and has cytotoxic effect on Leydig cells. Our studies showed that ZEN reduced the activity of Leydig cells, decreased testosterone secretion in Leydig cells, and caused DNA damage of the Leydig cells. However, the exact molecular mechanism remains unclear. In this project, we will use gene chip technology, two-dimensional electrophoresis technology and MALDI-TOF MS technology to compare the differences of the genome and proteome of the R2C Leydig cells after treatment by zearalenone on the Leydig cells, to identify the key regulatory genes and proteins in Leydig cells in the cytotoxicity induced by zearalenone, and then discuss the cellular signal transduction pathway and cytotoxic mechanism in Leydig cell injury by zearalenone. This study can provide the theoretical basis of the cytotoxic effect of zearalenone on genital system, help to prevent and control zearalenone toxication.

玉米赤霉烯酮（ZEN）毒素广泛存在于霉变谷类作物和奶制品中，具有很强的生殖毒性、免疫毒性、细胞毒性，对人和动物健康造成巨大危害，对养殖业造成严重的经济损失。已有大量研究表明，ZEN可引起雄性动物睾酮分泌减少，对睾丸间质细胞具有毒性作用。本课题组研究表明，ZEN可在体外降低睾丸间质细胞活性，减少睾酮分泌，造成睾丸间质细胞DNA损伤，但具体分子机制尚不清楚。因此，本项目拟采用基因芯片技术、双向电泳技术和生物质谱鉴定技术，通过比较ZEN作用大鼠睾丸间质细胞R2C后差异基因和差异蛋白，确定ZEN致睾丸间质细胞毒性作用的重要调控基因和蛋白，从而为探讨玉米赤霉烯酮致睾丸间质细胞损伤的细胞信号转导通路和毒性作用机理奠定基础。本研究结果可为今后深入研究该毒素雄性生殖毒性的分子作用机制提供理论依据。

蛋白质组学结果表明：iTRAQ核素标记和LC-MS/MS质谱检测鉴定ZEN作用于大鼠睾丸间质细胞R2c后检测差异蛋白共135个，其中上调的为59个、下调的为76个。分析差异蛋白结果表明，这些差异蛋白大多参与代谢进程和细胞定位，其中部分蛋白可能与ZEN致R2C细胞内质网氧化应激有关。经Western Blot验证，Bip，XBP-1蛋白表达明显上调，表明ZEN作用于R2c睾丸间质细胞时，确实能够引发内质网应激。基因组学结果表明：ZEN作用于小鼠睾丸间质细胞TM3，可显著影响细胞能量代谢相关通路，其次是免疫反应；ZEN可引起氧化磷酸化通路上多个基因上调和下调；ZEN可下调一些重要的免疫因子相关基因，如CXCL7，CXCL10，CXCL12，C3，CCL11等；ZEN可增强细胞动蛋白基因F-actin表达。结果首次证实，ZEN会增加癌症恶化和转移的几率。