Epigenetic control of lung fluid clearance

The Na,K-ATPase regulates ion transport and fluid balance in the lung, generating the driving force for alveolar fluid clearance (AFC). TGF-β mediates acute lung injury (ALI), and impacts AFC. We hypothesized that TGF-β impacts Na,K-ATPase function and activity by modifying subunit stoichiometry. Cell surface density of the Na,K-ATPase is regulated by the ATP1B1 subunit. Quantitative PCR analysis revealed that ATP1B1 gene expression was reduced both in TGF-β-treated A549 lung epithelial cell line and in lungs from ALI patients or mice with bleomycin-induced experimental ALI. Moreover, cell surface biotinylation…