TGR5 activation impairs lung natural killer cell function and promotes bile acid–mediated injury in metabolic liver disease - 18/08/26
, Ahmad SalhabAbstract |
Introduction and aim |
Bile acids (BAs) contribute to acute lung injury (ALI), yet their effects on pulmonary immune cells remain unclear. This study investigated whether elevated hepatic BA levels in metabolic dysfunction–associated steatohepatitis (MASH) promote lung injury by suppressing natural killer (NK) cell function through the bile acid receptor TGR5.
Methods |
Leptin-deficient ( Ob/Ob ) mice were fed a high-fat diet (HFD) for 16 weeks to induce MASH, while wild-type mice served as controls. Lung fibrosis was assessed histologically. NK cell activation (CD107a, NKp46) and TGR5 expression were analyzed by flow cytometry. Lung injury markers (SP-D and sRAGE) and BA concentrations in bronchoalveolar lavage fluid (BALF) were quantified. Ex-vivo assays evaluated the effects of taurocholic acid (TCA) and TGR5 blockade on NK cell activation.
Results |
Ob/Ob HFD mice developed MASH accompanied by lung injury and fibrotic remodeling. Lung weight increased by ∼1.5 g compared with controls. SP-D and sRAGE levels increased 2.5-fold and 2.0-fold, respectively (P < 0.01). BALF BA concentrations rose from 0.2 µM in controls to 1.2–1.9 µM in Ob/Ob HFD mice, indicating hepatic–pulmonary BA trafficking. NK cell activity was markedly suppressed, with a 3.5-fold reduction in activation, decreased CD107a expression, and a 1.75-fold reduction in NKp46 levels. TGR5 expression on lung NK cells increased ∼3.5-fold. TCA exposure impaired NK activation, whereas TGR5 blockade restored CD107a and NKp46 expression.
Conclusion |
BA–TGR5 signaling suppresses pulmonary NK cell function and contributes to lung injury in MASH, suggesting TGR5 as a potential therapeutic target for BA-driven immune dysfunction.
Le texte complet de cet article est disponible en PDF.Graphical Abstract |
Highlights |
• | Bile acids accumulate in lungs during metabolic liver disease. |
• | Lung NK cell activity is suppressed in MASH mice. |
• | Bile acids impair NK cell function via the TGR5 receptor. |
• | TGR5 expression is significantly increased on lung NK cells. |
• | TGR5 blockade restores NK cell activation after bile acid exposure. |
Keywords : Bile acids, TGR5 receptor, Natural killer cells, Metabolic dysfunction–associated steatohepatitis (MASH), Acute lung injury
Plan
Vol 202
Article 119732- septembre 2026 Retour au numéroBienvenue sur EM-consulte, la référence des professionnels de santé.
L’accès au texte intégral de cet article nécessite un abonnement.
Déjà abonné à cette revue ?
