DNA damage and changes of antioxidative enzymes in chronic benzene poisoning mice / 中华劳动卫生职业病杂志

ABSTRACT

<p><b>OBJECTIVE</b>To study the damage effect of benzene on DNA and its mechanism and the changes of antioxidative enzymes in vivo.</p><p><b>METHODS</b>DNA break in bone marrow cells and peripheral blood lymphocytes of mice exposed to benzene by 4 h static inhalation per day at different concentrations for two months were analyzed with single cell gel electrophoresis (SCGE). Meanwhile, the activity of SOD, GSH-Px and the level of MDA in liver, spleen and brain were detected.</p><p><b>RESULTS</b>In low and high dosage groups, the rate of DNA migration of bone marrow cells (83.56% +/- 10.28%, 92.54% +/- 15.93%) and peripheral blood lymphocytes (41.27% +/- 6.03%, 65.79% +/- 11.62%) were higher than those in control (4.13% +/- 0.52% and 2.21% +/- 0.31% respectively, P<0.05]. The activity of SOD in liver [(754.33 +/- 116.30), (694.26 +/- 116.30) U/mg pro] and GSH-Px [(22.52 +/- 3.31), (18.56 +/- 4.97) U/mg pro] were lower than those in control [(999.92 +/- 188.24) and (35.31 +/- 6.63) U/mg pro respectively, P<0.05, P<0.01]. But there was no significant difference between the two dosage groups. The activity of GSH-Px in spleen of both groups [(31.38 +/- 2.71), (25.30 +/- 7.44) U/mg pro] were lower than that of control [(37.11 +/- 3.42) U/mg pro, P<0.05] and there was significant difference between the two dosage groups. The activity of GSH-Px in brain of both groups [(5.70 +/- 0.84), (5.24 +/- 1.19) U/mg pro, P<0.05] were lower than that of control [(7.10 +/- 0.46) U/mg pro, P<0.05], but there was no significant difference between the two dosage groups. The level of MDA in brain of high dosage group [(3.99 +/- 1.15) nmol/mg pro] was higher than that of control [(2.58 +/- 0.53) nmol/mg pro, P<0.05].</p><p><b>CONCLUSION</b>Chronic benzene poisoning may result in DNA break in bone marrow cells and peripheral blood lymphocytes and decrease in the activity of antioxidative enzymes.</p>