Natália da Silva Lima1, Marcos F Fondevila2, Eva Nóvoa1, Xabier Buqué3, Maria Mercado-Gómez4, Sarah Gallet5, Maria J González-Rellan1, Uxia Fernandez1, Anne Loyens5, Maria Garcia-Vence6, Maria Del Pilar Chantada-Vazquez6, Susana B Bravo6, Patricia Marañon7, Ana Senra1, Adriana Escudero1, Magdalena Leiva8, Diana Guallar9, Miguel Fidalgo1, Pedro Gomes10, Marc Claret11, Guadalupe Sabio8, Marta Varela-Rey12, Teresa C Delgado4, Rocio Montero-Vallejo13, Javier Ampuero13, Miguel López2, Carlos Diéguez2, Laura Herrero14, Dolors Serra14, Markus Schwaninger15, Vincent Prevot5, Rocio Gallego-Duran16, Manuel Romero-Gomez17, Paula Iruzubieta18, Javier Crespo18, Maria L Martinez-Chantar19, Carmelo Garcia-Monzon20, Agueda Gonzalez-Rodriguez21, Patricia Aspichueta22, Ruben Nogueiras23. 1. Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain. 2. Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain; CIBER Fisiopatologia de la Obesidad y Nutrición (CIBERobn), Spain. 3. Department of Physiology, University of the Basque Country UPV/EHU, Spain; Biocruces Bizkaia Health Research Institute, Spain. 4. Liver Disease Lab, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), 48160 Derio, Bizkaia, Spain. 5. Univ. Lille, Inserm, CHU Lille, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Lille Neuroscience & Cognition, UMR-S 1172, European Genomic Institute for Diabetes (EGID), F-59000 Lille, France. 6. Proteomic Unit, Health Research Institute of Santiago de Compostela (IDIS), Santiago de Compostela, 15705 A Coruña, Spain. 7. LiverResearchUnit, Santa Cristina University Hospital, Instituto de Investigación Sanitaria Princesa, Madrid, Spain. 8. Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain. 9. Department of Biochemistry, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain. 10. Department of Biomedicine, Unit of Pharmacology and Therapeutics, Faculty of Medicine, University of Porto, Porto, Portugal; Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal; Institute of Pharmacology and Experimental Therapeutics, Coimbra Institute for Clinical and Biomedical Research(iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal. 11. Neuronal Control of Metabolism (NeuCoMe) Laboratory, Institut d'Investigacions Biomèdiques August Pi iSunyer (IDIBAPS), 08036, Barcelona, Spain; CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 08036, Barcelona, Spain. 12. Liver Disease Lab, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), 48160 Derio, Bizkaia, Spain; Gene Regulatory Control in Disease, CIMUS, University of Santiago de Compostela, Santiago de Compostela, Spain. 13. UGC Aparato Digestivo, Instituto de Biomedicina de Sevilla. Hospital Universitario Virgen del Rocío, Universidad de Sevilla, Sevilla, Spain. 14. CIBER Fisiopatologia de la Obesidad y Nutrición (CIBERobn), Spain; Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Barcelona, Spain. 15. University of Lübeck, Institute for Experimental and Clinical Pharmacology and Toxicology, Lübeck, Germany. 16. Neuronal Control of Metabolism (NeuCoMe) Laboratory, Institut d'Investigacions Biomèdiques August Pi iSunyer (IDIBAPS), 08036, Barcelona, Spain; CIBER Enfermedades Hepáticas y Digestivas (CIBERehd), Spain. 17. UGC Aparato Digestivo, Instituto de Biomedicina de Sevilla. Hospital Universitario Virgen del Rocío, Universidad de Sevilla, Sevilla, Spain; CIBER Enfermedades Hepáticas y Digestivas (CIBERehd), Spain. 18. Gastroenterology and Hepatology Department, Marqués de Valdecilla University Hospital. Clinical and Translational Digestive Research Group, IDIVAL, Santander, Spain. 19. Liver Disease Lab, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), 48160 Derio, Bizkaia, Spain; CIBER Enfermedades Hepáticas y Digestivas (CIBERehd), Spain. 20. LiverResearchUnit, Santa Cristina University Hospital, Instituto de Investigación Sanitaria Princesa, Madrid, Spain; CIBER Enfermedades Hepáticas y Digestivas (CIBERehd), Spain. 21. LiverResearchUnit, Santa Cristina University Hospital, Instituto de Investigación Sanitaria Princesa, Madrid, Spain; CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERdem), Spain. 22. Department of Physiology, University of the Basque Country UPV/EHU, Spain; Biocruces Bizkaia Health Research Institute, Spain; CIBER Enfermedades Hepáticas y Digestivas (CIBERehd), Spain. 23. Department of Physiology, CIMUS, University of Santiago de Compostela-Instituto de Investigación Sanitaria, Santiago de Compostela, Spain; CIBER Fisiopatologia de la Obesidad y Nutrición (CIBERobn), Spain. Electronic address: ruben.nogueiras@usc.es.
Abstract
BACKGROUND & AIMS: Autophagy-related gene 3 (ATG3) is an enzyme mainly known for its actions in the LC3 lipidation process, which is essential for autophagy. Whether ATG3 plays a role in lipid metabolism or contributes to non-alcoholic fatty liver disease (NAFLD) remains unknown. METHODS: By performing proteomic analysis on livers from mice with genetic manipulation of hepatic p63, a regulator of fatty acid metabolism, we identified ATG3 as a new target downstream of p63. ATG3 was evaluated in liver samples from patients with NAFLD. Further, genetic manipulation of ATG3 was performed in human hepatocyte cell lines, primary hepatocytes and in the livers of mice. RESULTS: ATG3 expression is induced in the liver of animal models and patients with NAFLD (both steatosis and non-alcoholic steatohepatitis) compared with those without liver disease. Moreover, genetic knockdown of ATG3 in mice and human hepatocytes ameliorates p63- and diet-induced steatosis, while its overexpression increases the lipid load in hepatocytes. The inhibition of hepatic ATG3 improves fatty acid metabolism by reducing c-Jun N-terminal protein kinase 1 (JNK1), which increases sirtuin 1 (SIRT1), carnitine palmitoyltransferase 1a (CPT1a), and mitochondrial function. Hepatic knockdown of SIRT1 and CPT1a blunts the effects of ATG3 on mitochondrial activity. Unexpectedly, these effects are independent of an autophagic action. CONCLUSIONS: Collectively, these findings indicate that ATG3 is a novel protein implicated in the development of steatosis. LAY SUMMARY: We show that autophagy-related gene 3 (ATG3) contributes to the progression of non-alcoholic fatty liver disease in humans and mice. Hepatic knockdown of ATG3 ameliorates the development of NAFLD by stimulating mitochondrial function. Thus, ATG3 is an important factor implicated in steatosis.
BACKGROUND & AIMS: Autophagy-related gene 3 (ATG3) is an enzyme mainly known for its actions in the LC3 lipidation process, which is essential for autophagy. Whether ATG3 plays a role in lipid metabolism or contributes to non-alcoholic fatty liver disease (NAFLD) remains unknown. METHODS: By performing proteomic analysis on livers from mice with genetic manipulation of hepatic p63, a regulator of fatty acid metabolism, we identified ATG3 as a new target downstream of p63. ATG3 was evaluated in liver samples from patients with NAFLD. Further, genetic manipulation of ATG3 was performed in human hepatocyte cell lines, primary hepatocytes and in the livers of mice. RESULTS: ATG3 expression is induced in the liver of animal models and patients with NAFLD (both steatosis and non-alcoholic steatohepatitis) compared with those without liver disease. Moreover, genetic knockdown of ATG3 in mice and human hepatocytes ameliorates p63- and diet-induced steatosis, while its overexpression increases the lipid load in hepatocytes. The inhibition of hepatic ATG3 improves fatty acid metabolism by reducing c-Jun N-terminal protein kinase 1 (JNK1), which increases sirtuin 1 (SIRT1), carnitine palmitoyltransferase 1a (CPT1a), and mitochondrial function. Hepatic knockdown of SIRT1 and CPT1a blunts the effects of ATG3 on mitochondrial activity. Unexpectedly, these effects are independent of an autophagic action. CONCLUSIONS: Collectively, these findings indicate that ATG3 is a novel protein implicated in the development of steatosis. LAY SUMMARY: We show that autophagy-related gene 3 (ATG3) contributes to the progression of non-alcoholic fatty liver disease in humans and mice. Hepatic knockdown of ATG3 ameliorates the development of NAFLD by stimulating mitochondrial function. Thus, ATG3 is an important factor implicated in steatosis.
Authors: Jerome Garcia; Rudy Chang; Ross A Steinberg; Aldo Arce; Joshua Yang; Peter Van Der Eb; Tamara Abdullah; Devaraj V Chandrashekar; Sydney M Eck; Pablo Meza; Zhang-Xu Liu; Enrique Cadenas; David H Cribbs; Neil Kaplowitz; Rachita K Sumbria; Derick Han Journal: Front Physiol Date: 2022-09-15 Impact factor: 4.755