刚地弓形虫感染致小鼠睾丸细胞DNA的损伤作用

DNA damage in mice testicular cell caused by Toxoplasma gondii infection

目的探讨刚地弓形虫感染对小鼠睾丸细胞DNA的损伤作用。方法选用9～10周龄雄性BALB／c小鼠20只，随机分为对照组（CG）和3个染虫组（G1、G2和G3）。采用腹腔注射法建立小鼠刚地弓形虫感染的动物模型，CG组注射PBS0．2ml／只，染虫G1、G2和G3组各注射纯化刚地弓形虫速殖子悬液0．2ml，剂量分别为2．5×10^3个、5×10^3个和1×10^4个。应用单细胞凝胶电泳（彗星实验）检测睾丸细胞DNA的损伤。结果对照组和3个染虫组的彗星实验尾矩分别为10．94±7．57、40．37±6．25、69．76±3．97和79．16±6．36；Olive尾矩分别为10．57±6．72、31．39±4．59、48．66±4．60和53．87±6．55，对照组和实验组彗星尾矩和Olive尾矩差异有统计学意义（P〈0．01）。结论弓形虫感染可致小鼠睾丸细胞DNA不同程度的损伤。对小鼠有生殖遗传毒性。

Objective To explore the adverse effect caused by infection of Toxoplasma gondii on the mice testicular cell. Methods Twenty BALB/c male mice （9--10 weeks old） were randomized into 4 groups, one negative control group（CG）, three experimental group （G1： 2. 5 × 10^3 , G2：5 × 10^3 and G3：1 × 10^4 tachyzoites）. The negative control group was injected intraperitoneally with PBS and the experimental group was inoculated intraperitoneally with T. gondii tachyzoites （RH strain）. All mice were sacrificed 6 days after infection and the testicular cells were applied onto single cell gel electrophoresis （comet assay） for detection of DNA damage. Results The tail moment mean value of the negative control group was 10.94± 7.57. Three experimental groups mean values of tail moment each were 40. 37±6.25, 69.76 ± 3.97 and 79.16 ±6.36. Significant difference in tail moment had been seen between the experimental groups and the negative control group （P〈0. 01）. Similar difference in Olive tail moment were observed among the experimental groups and the negative control group （P〈0.01）. Conclusion T. gondii could cause DNA damage of mice testicular cell and have genetic genotoxicity to mice.