Figure 6.

Gene expression of NF-E2 related factor-2 (NRF-2) and downstream antioxidant genes in wild-type (WT) and surfactant protein D overexpressing (SP-D OE) mice. Total lung mRNA was extracted from SP-D OE and littermate WT mice exposed to 21% or 80% O₂ for 5 days. Quantitative real-time reverse transcription–polymerase chain reaction analysis was performed for NRF-2, glutathione peroxidase-2 (Gpx-2), hemoxygenase-1 (HO-1), and NAD(P)H quinone oxidoreductase-1 (Nqo-1) and normalized to 18S RNA as described. Data are expressed as mean ± SEM (n = 5–10), normalized to WT level (*P < 0.05; ***P < 0.0001 vs. SP-D OE normoxia group). Hyperoxia-exposed SP-D OE mice exhibit significantly higher levels of NRF-2, GPx-2, HO-1, and Nqo-1 mRNA in the lung as compared with similarly exposed WT group.