Effects of sulfur dioxide on expressions of p53, bax and bcl-2 in lungs of asthmatic rats

Abstract

Inhibition of cell apoptosis is an increasingly important factor in modulating airway inflammation in asthma, which is related to environmental pollutants. To investigate the effects of sulfur dioxide (SO₂) on the mRNA and protein expressions of apoptosis-related genes in lungs from asthmatic rats, male Wistar rats were challenged by ovalbumin (OVA) or SO₂ (2 ppm) inhalation alone or together. Examinations were performed 24 h after the last treatment. The mRNA and protein levels of p53, bax, and bcl-2 were analyzed in lungs using real-time reverse transcription-polymerase chain reaction (RT-PCR) assay and Western blot analysis, respectively. The results indicated that increases of bcl-2 or decreases of p53 and bax mRNA and protein levels were not significant in lungs of rats exposed to SO₂ alone, compared with controls, but elevated or reduced levels of these genes appeared in lungs of asthmatic rats exposed to SO₂ plus OVA, compared with controls, suggesting that SO₂ exposure could result in OVA-induced increases or decreases of transcription and translation levels of these apoptosis-related genes in rat lungs, and may have relations to airway inflammation in asthma. The regulation mechanism of apoptosis in asthma disease exposure to SO₂ needs further study.

Keywords::

• sulfur dioxide
• asthmatic rats
• lungs
• bax
• bcl-2
• p53

Acknowledgements

This research was supported by grant nos. 20677035 and 30740037 from the National Natural Science Foundation of China.