Figure 7

Gene transfer of the Na⁺,K⁺-ATPase β1 subunit has the unique ability, compared to the β2 and β3 subunits, to restore ZO-1, occludin, and VE-cadherin expression in previously LPS injured lungs. Lung injury was established in C57B6 mice (n = 6–8) by aspiration of LPS (5 mg/kg) and 1 day later plasmids (100 μg each) expressing either no insert (pcDNA3), or the β1, β2, or β3 subunits of the Na⁺,K⁺-ATPase (β1, β2, or β3) were delivered in 50 μl to the lungs by aspiration followed immediately by electroporation. Two days later, lungs were perfused with PBS and lysates were prepared for analysis by Western Blot (A). Levels of expression were normalized to GAPDH as a loading control and the relative expression of Occludin (B) and ZO-1 (C) are shown as mean ± SEM. All experiments were carried out three times and representative experiments are shown. One-way ANOVA with post-hoc Tukey’s multiple comparisons was used for statistical analysis; For Occludin (B) a, p < 0.01 compared to naïve; b, p < 0.001 compared to naïve; c, p < 0.05 compared to LPS alone; d, p < 0.01 compared to LPS + pcDNA3; e, p < 0.01 compared to LPS + β1; f, p < 0.05 compared to LPS + β1. For ZO-1 (C) a, p < 0.01 compared to naïve; b, p < 0.05 compared to LPS alone; c, p < 0.05 compared to LPS + pcDNA3. Full gels are in Fig. S3.