Amel Ben Saad1,2, Virginie Vauthier2,3, Ágota Tóth4, Angelika Janaszkiewicz4, Anne-Marie Durand-Schneider2, Alix Bruneau2,5, Jean-Louis Delaunay2, Martine Lapalus1, Elodie Mareux1, Isabelle Garcin1, Emmanuel Gonzales1,6, Chantal Housset2,7, Tounsia Aït-Slimane2, Emmanuel Jacquemin1,6, Florent Di Meo4, Thomas Falguières1. 1. Inserm, Université Paris-Saclay, Physiopathogénèse et traitement des maladies du foie, UMR_S 1193, Orsay, France. 2. Inserm, Sorbonne Université, Centre de Recherche Saint-Antoine (CRSA), UMR_S 938, Institute of Cardiometabolism and Nutrition (ICAN), Paris, France. 3. Université de Paris, Institut Cochin, Inserm U1016, CNRS UMR 8104, Paris, France. 4. Inserm, Université de Limoges, UMR 1248 IPPRITT, Limoges, France. 5. Department of Hepatology & Gastroenterology, Charité Universitätsmedizin Berlin, Berlin, Germany. 6. Assistance Publique - Hôpitaux de Paris, CHU Bicêtre, Paediatric Hepatology & Paediatric Liver Transplant Department, Reference Center for Rare Paediatric Liver Diseases, FILFOIE, ERN Rare-Liver, Faculté de Médecine Paris-Saclay, Le Kremlin-Bicêtre, France. 7. Assistance Publique - Hôpitaux de Paris, Hôpital Saint-Antoine, Reference Center for Inflammatory Biliary Diseases and Autoimmune Hepatitis, FILFOIE, ERN Rare-Liver, Paris, France.
Abstract
BACKGROUND & AIM: ABCB4 is expressed at the canalicular membrane of hepatocytes. This ATP-binding cassette (ABC) transporter is responsible for the secretion of phosphatidylcholine into bile canaliculi. Missense genetic variations of ABCB4 are correlated with several rare cholestatic liver diseases, the most severe being progressive familial intrahepatic cholestasis type 3 (PFIC3). In a repurposing strategy to correct intracellularly retained ABCB4 variants, we tested 16 compounds previously validated as cystic fibrosis transmembrane conductance regulator (CFTR) correctors. METHODS: The maturation, intracellular localization and activity of intracellularly retained ABCB4 variants were analyzed in cell models after treatment with CFTR correctors. In addition, in silico molecular docking calculations were performed to test the potential interaction of CFTR correctors with ABCB4. RESULTS: We observed that the correctors C10, C13, and C17, as well as the combinations of C3 + C18 and C4 + C18, allowed the rescue of maturation and canalicular localization of four distinct traffic-defective ABCB4 variants. However, such treatments did not permit a rescue of the phosphatidylcholine secretion activity of these defective variants and were also inhibitory of the activity of wild type ABCB4. In silico molecular docking analyses suggest that these CFTR correctors might directly interact with transmembrane domains and/or ATP-binding sites of the transporter. CONCLUSION: Our results illustrate the uncoupling between the traffic and the activity of ABCB4 because the same molecules can rescue the traffic of defective variants while they inhibit the secretion activity of the transporter. We expect that this study will help to design new pharmacological tools with potential clinical interest.
BACKGROUND & AIM: ABCB4 is expressed at the canalicular membrane of hepatocytes. This ATP-binding cassette (ABC) transporter is responsible for the secretion of phosphatidylcholine into bile canaliculi. Missense genetic variations of ABCB4 are correlated with several rare cholestatic liver diseases, the most severe being progressive familial intrahepatic cholestasis type 3 (PFIC3). In a repurposing strategy to correct intracellularly retained ABCB4 variants, we tested 16 compounds previously validated as cystic fibrosis transmembrane conductance regulator (CFTR) correctors. METHODS: The maturation, intracellular localization and activity of intracellularly retained ABCB4 variants were analyzed in cell models after treatment with CFTR correctors. In addition, in silico molecular docking calculations were performed to test the potential interaction of CFTR correctors with ABCB4. RESULTS: We observed that the correctors C10, C13, and C17, as well as the combinations of C3 + C18 and C4 + C18, allowed the rescue of maturation and canalicular localization of four distinct traffic-defective ABCB4 variants. However, such treatments did not permit a rescue of the phosphatidylcholine secretion activity of these defective variants and were also inhibitory of the activity of wild type ABCB4. In silico molecular docking analyses suggest that these CFTR correctors might directly interact with transmembrane domains and/or ATP-binding sites of the transporter. CONCLUSION: Our results illustrate the uncoupling between the traffic and the activity of ABCB4 because the same molecules can rescue the traffic of defective variants while they inhibit the secretion activity of the transporter. We expect that this study will help to design new pharmacological tools with potential clinical interest.
Authors: Victor Emanuel Miranda Soares; Thiago Inácio Teixeira do Carmo; Fernanda Dos Anjos; Jonatha Wruck; Sarah Franco Vieira de Oliveira Maciel; Margarete Dulce Bagatini; Débora Tavares de Resende E Silva Journal: Mol Cell Biochem Date: 2021-09-16 Impact factor: 3.396