OBJECTIVETo 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.

METHODSMale Kunming mice were divided randomly into 8 groups, including negative control group, reagent control group, 100 mg/kg benzene group, 200 mg/kg benzene 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 TRAPELISA.

RESULTSCompared with negative and reagent control 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).

CONCLUSIONIncreased telomerase activity in lymphocytes stimulated by benzene at different concentrations indicates activation and proliferation of these lymphocytes of mice in vivo. Telomerase activity is probably a sensitive early marker of lymphocyte proliferation by benzene. Selenium can upregulate the telomerase activity.