The effects of Nrf2 gene expression induced by RU486 at different doses on A549 cell damage induced by paraquat / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To observe the effects of Nrf2 gene expression induced by RU486 at different doses on A549 cell damage induced by paraquat (PQ).</p><p><b>METHODS</b>After A549 cells transfected with Ad-RUNrf2 were treated by RU486 at the doses of 10(-10), 10(-9), 10(-8) and 10(-7) mol/L for 6 h, A549 cell cultures were exposed to 10(-3) mol/L of PQ for 48 h. Then qRT-PCR and EMSA assays were used to detect the expression of Nrf2 gene, and qRT-PCR and ELISA assays were utilized to measure the effects of Nrf2 gene on the expression of the inflammatory cytokines IL-6, IL-10 and TNF-α, apoptotic factors Caspase-3, Caspase-9 and Cytochrome C. The oxidation factors (CAT and MDA protein contents) were observed by Chemical Colorimetric Analysis.</p><p><b>RESULTS</b>Nrf2 gene relative expression and protein contents increased with RU486 concentrations, and the above expression was the highest when the concentration of RU486 was 10(-7) mol/L, which was significantly higher than those in control and PQ exposure groups (P < 0.01 or P < 0.05). The relative gene expression and protein expression of IL-6 and TNF-α enhanced with the reduced concentrations of RU486, which were the lowest when RU486 concentration was 10(-7) mol/L, as compared with control and PQ exposure groups (P < 0.01 or P < 0.05), while the change of IL-10 content was the opposite. The relative expression of Caspase3, Caspase9 and Cytochrome C genes also increased with the reduced concentrations of RU486, which were the lowest when RU486 concentration was 10(-7) mol/L, as compared with control and PQ exposure groups (P < 0.01 or P < 0.05). The content of CAT enhanced with RU486 concentration, which was the highest when RU486 concentration was 10(-7) mol/L, as compared with control and PQ exposure groups (P < 0.05). But the change of MDA content was the contrary.</p><p><b>CONCLUSION</b>Nrf2 expression induced by RU486 can promote the balance of oxidation-antioxidation system in A549 cells and inhibit the inflammation and apoptosis factors, which has a protective effect on A549 cell injury induced by PQ.</p>

Effect of bromoxynil on membrane potential and respiratory control rate in isolated mitochondria from mice liver and intervention effect of NAC / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To demonstrate the effect of bromoxynil on membrane potential and respiratory control rate (RCR) in isolate mitochondria from mice liver tissue in vitro and the intervention of NAC.</p><p><b>METHODS</b>The mitochondrial was randomized to control group, bromoxynil-poisoned group and NAC-protected group. S3, S4 and RCR of the mitochondria in each sample was detected by the method of oxygen electrode. Each sample was stained by JC-1 and the changes of membrane potential of mitochondria were observed under fluorescence microscope.</p><p><b>RESULTS</b>The S3 [(0.031 +/- 0.008) nano atoms oxygen x mg(-1) x min(-1)], RCR (1.820 +/- 0.181) of bromoxynil-poisoned group and RCR (4.253 +/- 0.210) of NAC-protected group were significantly lower than those of control group (P<0.01); the S4 [(0.017 +/- 0.004) nano atoms oxygen x mg(-1) x min(-1)] of NAC-protected group was significantly higher than control group (P<0.01). The S3 [(0.046 +/- 0.005) nano atoms oxygen x mg(-1) x min(-1)] and RCR of NAC-protected group were significantly higher than group B (P<0.01), S4 [(0.011 +/- 0.001) nano atoms oxygen x mg(-1) x min(-1)] of NAC-protected group was significantly lower than bromoxynil-poisoned group (P< 0.01). Observation under fluorescence microscope: the red fluorescence of mitochondria was dim or disappeared in bromoxynil-poisoned group while brightened in NAC-protected group but still dimmer than control group.</p><p><b>CONCLUSION</b>In vitro, the mitochondrial RCR and the mitochondrial membrane potential are decreased after the mitochondria is incubated with bromoxynil, and NAC could improve it.</p>