Losartan ameliorates TGF-β1-induced CFTR dysfunction and improves correction by cystic fibrosis modulator therapies

• Published in: The Journal of clinical investigation Vol. 132; no. 11; pp. 1 - 6
• Main Authors: Kim, Michael D, Bengtson, Charles D, Yoshida, Makoto, Niloy, Asef J, Dennis, John S, Baumlin, Nathalie, Salathe, Matthias
• Format: Journal Article
• Language: English
• Published: United States American Society for Clinical Investigation 01.06.2022
• Subjects: Angiotensin; Angiotensin II; Benzodioxoles - pharmacology; Biomedical research; Chloride; Concise Communication; Cyclooxygenase 2 - metabolism; Cyclooxygenase-2; Cystic fibrosis; Cystic Fibrosis - drug therapy; Cystic Fibrosis - genetics; Cystic Fibrosis - metabolism; Cystic Fibrosis Transmembrane Conductance Regulator - metabolism; Epithelial cells; Epithelium; Gene expression; Humans; Hydration; Inflammation; Losartan - pharmacology; Lung diseases; Mutation; Potentiation; Proteins; Pulmonology; Respiratory function; Respiratory tract; RNA, Messenger; Transforming Growth Factor beta1 - genetics; Transforming Growth Factor beta1 - metabolism; Transforming growth factor-b1; Tumor Necrosis Factor-alpha - genetics; Tumor Necrosis Factor-alpha - metabolism; Tumor necrosis factor-α; Pulmonology; Inflammation; Ion channels
• ISSN: 1558-8238; 0021-9738; 1558-8238
• DOI: 10.1172/JCI155241

Highly effective modulator therapies dramatically improve the prognosis for those with cystic fibrosis (CF). The triple combination of elexacaftor, tezacaftor, and ivacaftor (ETI) benefits many, but not all, of those with the most common F508del mutation in the CF transmembrane conductance regulator (CFTR). Here, we showed that poor sweat chloride concentration responses and lung function improvements upon initiation of ETI were associated with elevated levels of active TGF-β1 in the upper airway. Furthermore, TGF-β1 impaired the function of ETI-corrected F508del-CFTR, thereby increasing airway surface liquid (ASL) absorption rates and inducing mucus hyperconcentration in primary CF bronchial epithelial cells in vitro. TGF-β1 not only decreased CFTR mRNA, but was also associated with increases in the mRNA expression of TNFA and COX2 and TNF-α protein. Losartan improved TGF-β1-mediated inhibition of ETI-corrected F508del-CFTR function and reduced TNFA and COX2 mRNA and TNF-α protein expression. This likely occurred by improving correction of mutant CFTR rather than increasing its mRNA (without an effect on potentiation), thereby reversing the negative effects of TGF-β1 and improving ASL hydration in the CF airway epithelium in vitro. Importantly, these effects were independent of type 1 angiotensin II receptor inhibition.