Oxidative Stress Produced by Hyperthyroidism Status Induces the Antioxidant Enzyme Transcription through the Activation of the Nrf-2 Factor in Lymphoid Tissues of Balb/c Mice

Figure 4

Induction of ROS on the genomic expression of antioxidant enzymes. (a) Lymph nodes and spleen cells of euthyroid mice were incubated at 37°C in the absence or presence of H₂O₂ (250 μM) for 4 hours and/or N-acetyl-cysteine (NAC; 2 mM) for 12 hours. Then, the genomic expression of CAT, GPX-1, and SOD-1 was evaluated by conventional PCR. The amplified products were subjected to agarose gel electrophoresis and stained with ethidium bromide. Representative gels from 3 independent experiments performed in duplicate are shown. The bar graph shows the densitometric analysis of each band relativized to β-microglobulin used as housekeeping. differs significantly from control cells without treatment with ; # differs significantly from cells treated with H₂O₂ with . (b) The lymph node and spleen cells were treated as described above, and then, the cells were incubated with 10 μM DCFH-DA to evaluate the production of reactive oxygen species by a flow cytometer. Histograms show the production of ROS in lymph node cells subjected to different treatments. Similar results were obtained in spleen cells (data not shown). The average values of mean fluorescence intensity are indicated in the table. The results shown are representative of 3 independent experiments performed in duplicate. differs significantly from control cells without treatment with ; # differs significantly from cells treated with H₂O₂ with .

(a)

(b)