Background: One of the mechanisms of action of nitrofen is intracellular oxidative stress. It is therefore likely that anti-oxidant agents can counteract its action. The aim of this study was to examine whether vitamin C mitigates the effects of nitrofen on the proliferation/apoptosis balance and functional maturation of cultured human pneumocytes.
Methods: Lung aCa type II pneumocytes (NIH-H441) in culture were exposed to 1.5 microM of nitrofen alone or followed 48 h later by 60 microM of vitamin C. The culture dishes were recovered at 72 h for immunohistochemical (PCNA for proliferation, bis-benzimide for apoptosis, anti-SpB and anti-TTF-1 antibodies for SpB and TTF-1 assessment) and molecular studies. Real-time PCR was used to quantitate TTF-1 RNAm, with S26 as internal control. ANOVA or Kruskall-Wallis with appropriate post hoc tests were used for comparison with p<0.05 as threshold of significance.
Results: Nitrofen decreased proliferation and TTF/1 and SpB expression with no apparent affect on apoptosis. Additional exposure to vitamin C reverted these effects. Furthermore, nitrofen decreased TTF/1 mRNA and vitamin C tended to rescue normal values.
Conclusions: Vitamin C partially rescued proliferation and maturity in nitrofen-treated human pneumocytes. The likely beneficial influence of this prenatal anti-oxidant medication should be further investigated.