苯和硒对小鼠淋巴细胞端粒酶活力的影响

Effects of benzene and selenium on telomerase in mouse lymphocytes in vivo

目的 研究苯和硒对小鼠淋巴细胞端粒酶活力的影响，评价端粒酶作为苯刺激淋巴细胞的早期效应标志物的可能性。方法健康雄性昆明种小鼠随机分为阴性对照组，溶剂对照组，100、200、400mg／kg苯组，200mg／kg苯＋0．75mg／kg亚硒酸钠组，200mg／kg苯＋1．50mg／kg亚硒酸钠组，200mg／kg苯＋3．00mg／kg亚硒酸钠组，每组5只。各组分别给予不同处理，共5d，每天1次。最后1次染毒48h后，分离淋巴细胞，用端粒重复扩增一酶联免疫吸附（TRAP-ELISA）法检测端粒酶活力。结果各剂量苯组的端粒酶活力均增加，与阴性对照组和溶剂对照组比较，其中，100mg／kg苯组差异有统计学意义（P〈0．01）。各剂量苯联合硒组的端粒酶活力均增加，与阴性对照组和溶剂对照组比较，200mg／kg苯＋O．75mg／kg亚硒酸钠组差异有统计学意义（P〈0．01）；与相应的200mg／kg苯组比较，200mg／kg苯＋O．75mg／kg亚硒酸钠组差异有统计学意义（P〈0．05）。结论不同浓度的苯刺激的端粒酶活力均增加，表明小鼠淋巴细胞得到激活和增殖。端粒酶可能是苯刺激淋巴细胞的一种敏感的早期效应标志物。硒可以上调小鼠淋巴细胞端粒酶活力。

Objective To study the effects of benzene and selenium on telomerase in mouse lymphocytes in vivo and evaluate telomerase activity as an early marker of benzene effects on lymphocytes. Methods Male Kunming mice were divided randomly into 8 groups,including negative control group, reagent control group, 100 mg/kg benzene group, 200 mg/kg henzene group,400 mg/kg benzene group,200 mg/kg benzene ＋ 0.75 mg/kg selenium group, 200 mg/kg benzene ＋ 1.50 mg/kg selenium group and 200 mg/kg benzene ＋ 3.00 mg/kg selenium group, 5 mice in each group. The mice in different groups were treated with different methods, once daily for 5 days. After 48 hours of the final exposure, lymphocytes were separated and the telomerase activities were detected with TRAP-ELISA. Results Compared with negative and reagent con- trol groups, the telomerase activity was increased after treatment with different dose of benzene and at the dose of 100 mg/kg benzene group it was significantly increased （P〈0.01）. At the dose of 200 mg/kg benzene ＋ 0.75 mg/kg selenium group,it was significantly increased（P〈0.01 ）. Compared with the counterpart treated with 200 mg/kg benzene group, the expression of telomerase was increased at the different concentrations after treatment with benzene combined with selenium and it was significantly increased at the dose of 200 mg/kg benzene ＋ 0.75 mg/kg selenium group（P〈0.05 ）. Conclusion Increased telomerase activity in lymphocytes stimulated by benzene at different concentrations indicates activation and proliferation of these lymphocytes of mice in vi-vo. Telomerase activity is probably a sensitive early marker of lymphocyte proliferation by benzene. Selenium can upregulate the telomerase activity.