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Mancina RM, Sasidharan K, Lindblom A, Wei Y, Ciociola E, Jamialahmadi O, Pingitore P, Andréasson AC, Pellegrini G, Baselli G, Männistö V, Pihlajamäki J, Kärjä V, Grimaudo S, Marini I, Maggioni M, Becattini B, Tavaglione F, Dix C, Castaldo M, Klein S, Perelis M, Pattou F, Thuillier D, Raverdy V, Dongiovanni P, Fracanzani AL, Stickel F, Hampe J, Buch S, Luukkonen PK, Prati D, Yki-Järvinen H, Petta S, Xing C, Schafmayer C, Aigner E, Datz C, Lee RG, Valenti L, Lindén D, Romeo S. PSD3 downregulation confers protection against fatty liver disease. Nat Metab 2022; 4:60-75. [PMID: 35102341 PMCID: PMC8803605 DOI: 10.1038/s42255-021-00518-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 12/08/2021] [Indexed: 12/17/2022]
Abstract
Fatty liver disease (FLD) is a growing health issue with burdening unmet clinical needs. FLD has a genetic component but, despite the common variants already identified, there is still a missing heritability component. Using a candidate gene approach, we identify a locus (rs71519934) at the Pleckstrin and Sec7 domain-containing 3 (PSD3) gene resulting in a leucine to threonine substitution at position 186 of the protein (L186T) that reduces susceptibility to the entire spectrum of FLD in individuals at risk. PSD3 downregulation by short interfering RNA reduces intracellular lipid content in primary human hepatocytes cultured in two and three dimensions, and in human and rodent hepatoma cells. Consistent with this, Psd3 downregulation by antisense oligonucleotides in vivo protects against FLD in mice fed a non-alcoholic steatohepatitis-inducing diet. Thus, translating these results to humans, PSD3 downregulation might be a future therapeutic option for treating FLD.
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Grants
- the MyFirst Grant AIRC n.16888, Ricerca Finalizzata Ministero della Salute RF-2016-02364358 (LV), Ricerca Corrente Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico (LV), and the European Union (EU) Programme Horizon 2020 (under grant agreement no. 777377) for the project LITMUS–“Liver Investigation: Testing Marker Utility in Steatohepatitis” (LV).
- Swedish Research Council (Vetenskapsradet (VR), 2021-005208) (SR), the Swedish state under the Agreement between the Swedish government and the county councils (the ALF agreement, SU 2018-04276) (SR), the Swedish Diabetes Foundation (DIA2020-518) (SR), the Swedish Heart Lung Foundation (20200191) (SR), the Wallenberg Academy Fellows from the Knut and Alice Wallenberg Foundation (KAW 2017.0203) (SR), the Novonordisk Project grants in Endocrinology and Metabolism (NNF20OC0063883) (SR), Astra Zeneca Agreement for Research, and Grant SSF ITM17-0384 (SR), Swedish Foundation for Strategic Research (SR)
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Affiliation(s)
- Rosellina M Mancina
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Kavitha Sasidharan
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Anna Lindblom
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism (CVRM) BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Ying Wei
- Ionis Pharmaceuticals, Carlsbad, CA, USA
| | - Ester Ciociola
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Oveis Jamialahmadi
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Piero Pingitore
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Anne-Christine Andréasson
- Bioscience Cardiovascular, Research and Early Development Cardiovascular, Renal and Metabolism (CVRM) BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Giovanni Pellegrini
- Pathology, Clinical Pharmacology and Safety Sciences BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Guido Baselli
- Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico and Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Ville Männistö
- Department of Medicine, University of Eastern Finland and Kuopio University Hospital, Kuopio, Finland
| | - Jussi Pihlajamäki
- Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
- Clinical Nutrition and Obesity Centre, Kuopio University Hospital, Kuopio, Finland
| | - Vesa Kärjä
- Department of Pathology, University of Eastern Finland and Kuopio University Hospital, Kuopio, Finland
| | - Stefania Grimaudo
- Section of Gastroenterology and Hepatology, PROMISE, University of Palermo, Palermo, Italy
| | - Ilaria Marini
- Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico and Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Marco Maggioni
- Department of Pathology, Fondazione Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Barbara Becattini
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Federica Tavaglione
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Carly Dix
- Antibody Discovery and Protein Engineering (ADPE), AstraZeneca, Cambridge, UK
| | - Marie Castaldo
- Discovery Biology, Discovery Sciences R&D, AstraZeneca, Gothenburg, Sweden
| | | | | | - Francois Pattou
- University of Lille, Inserm, Lille Pasteur Institute, CHU Lille, European Genomic Institute for Diabetes, U1190 Translational Research in Diabetes, Lille University, Lille, France
- CHU Lille, Department of General and Endocrine Surgery, Intergrated Center for Obesity, Lille, France
| | - Dorothée Thuillier
- University of Lille, Inserm, Lille Pasteur Institute, CHU Lille, European Genomic Institute for Diabetes, U1190 Translational Research in Diabetes, Lille University, Lille, France
| | - Violeta Raverdy
- University of Lille, Inserm, Lille Pasteur Institute, CHU Lille, European Genomic Institute for Diabetes, U1190 Translational Research in Diabetes, Lille University, Lille, France
- CHU Lille, Department of General and Endocrine Surgery, Intergrated Center for Obesity, Lille, France
| | - Paola Dongiovanni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Anna Ludovica Fracanzani
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Felix Stickel
- Department of Gastroenterology and Hepatology, University Hospital of Zurich, Zurich, Switzerland
| | - Jochen Hampe
- Medical Department 1, University Hospital Dresden, Technische Universitaät Dresden (TU Dresden), Dresden, Germany
| | - Stephan Buch
- Medical Department 1, University Hospital Dresden, Technische Universitaät Dresden (TU Dresden), Dresden, Germany
| | - Panu K Luukkonen
- Department of Medicine, University of Helsinki and Helsinki University Central Hosptial, Helsinki, Finland
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
- Department of Internal Medicine, Yale University, New Haven, CT, USA
| | - Daniele Prati
- Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico and Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Hannele Yki-Järvinen
- Department of Medicine, University of Helsinki and Helsinki University Central Hosptial, Helsinki, Finland
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | - Salvatore Petta
- Section of Gastroenterology and Hepatology, PROMISE, University of Palermo, Palermo, Italy
| | - Chao Xing
- McDermott Center for Human Growth and Development University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Clemens Schafmayer
- Department of General, Visceral, Vascular and Transplantation Surgery, University of Rostock, Rostock, Germany
| | - Elmar Aigner
- First Department of Medicine, Paracelsus Medical University, Salzburg, Austria
| | - Christian Datz
- Department of Internal Medicine, General Hospital Oberndorf, Teaching Hospital of the Paracelsus Medical University Salzburg, Oberndorf, Austria
| | | | - Luca Valenti
- Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico and Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Daniel Lindén
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism (CVRM) BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden.
- Division of Endocrinology, Department of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden.
- Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden.
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, University Magna Graecia, Catanzaro, Italy.
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Caddeo A, Hedfalk K, Romeo S, Pingitore P. LPIAT1/MBOAT7 contains a catalytic dyad transferring polyunsaturated fatty acids to lysophosphatidylinositol. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:158891. [PMID: 33513444 DOI: 10.1016/j.bbalip.2021.158891] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 01/13/2021] [Accepted: 01/23/2021] [Indexed: 11/17/2022]
Abstract
Human membrane bound O-acyltransferase domain-containing 7 (MBOAT7), also known as lysophosphatidylinositol acyltransferase 1 (LPIAT1), is an enzyme involved in the acyl-chain remodeling of phospholipids via the Lands' cycle. The MBOAT7 rs641738 variant has been associated with the entire spectrum of fatty liver disease (FLD) and neurodevelopmental disorders, but the exact enzymatic activity and the catalytic site of the protein are still unestablished. Human wild type MBOAT7 and three MBOAT7 mutants missing in the putative catalytic residues (N321A, H356A, N321A + H356A) were produced into Pichia pastoris, and purified using Ni-affinity chromatography. The enzymatic activity of MBOAT7 wild type and mutants was assessed measuring the incorporation of radiolabeled fatty acids into lipid acceptors. MBOAT7 preferentially transferred 20:4 and 20:5 polyunsaturated fatty acids (PUFAs) to lysophosphatidylinositol (LPI). On the contrary, MBOAT7 showed weak enzymatic activity for transferring saturated and unsaturated fatty acids, regardless the lipid substrate. Missense mutations in the putative catalytic residues (N321A, H356A, N321A + H356A) result in a loss of O-acyltransferase activity. Thus, MBOAT7 catalyzes the transfer of PUFAs to lipid acceptors. MBOAT7 shows the highest affinity for LPI, and missense mutations at the MBOAT7 putative catalytic dyad inhibit the O-acyltransferase activity of the protein. Our findings support the hypothesis that the association between the MBOAT7 rs641738 variant and the increased risk of NAFLD is mediated by changes in the hepatic phosphatidylinositol acyl-chain remodeling. Taken together, the increased knowledge of the enzymatic activity of MBOAT7 gives insights into the understanding on the basis of FLD.
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Affiliation(s)
- Andrea Caddeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - Kristina Hedfalk
- Department of Chemistry and Molecular Biology, University of Gothenburg, Sweden
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden; Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden; Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy.
| | - Piero Pingitore
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden.
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Schwartz BE, Rajagopal V, Smith C, Cohick E, Whissell G, Gamboa M, Pai R, Sigova A, Grossman I, Bumcrot D, Sasidharan K, Romeo S, Sehgal A, Pingitore P. Discovery and Targeting of the Signaling Controls of PNPLA3 to Effectively Reduce Transcription, Expression, and Function in Pre-Clinical NAFLD/NASH Settings. Cells 2020; 9:cells9102247. [PMID: 33036387 PMCID: PMC7600576 DOI: 10.3390/cells9102247] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/01/2020] [Accepted: 10/05/2020] [Indexed: 02/07/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are emerging worldwide epidemics, projected to become the leading cause of liver transplants. The strongest genetic risk factor for NAFLD/NASH susceptibility and progression is a single-nucleotide polymorphism (SNP) in the patatin-like phospholipase domain-containing 3 gene (PNPLA3), rs738409, encoding the missense mutation I148M. This aminoacidic substitution interferes with the normal remodeling of lipid droplets in hepatocytes. It is also thought to play a key role in promoting liver fibrosis by inhibiting the release of retinol from hepatic stellate cells. Reducing PNPLA3 levels in individuals homozygous for 148M may be an effective treatment for the entire spectrum of NAFLD, based on gene dosage analysis in the human population, as well as the protective effect of another naturally occurring SNP (rs2294918) in PNPLA3 which, when co-inherited, reduces PNPLA3 mRNA levels to 50% and counteracts disease risk. By screening a clinical compound library targeting specific signaling pathways active in primary human hepatocytes, we identified momelotinib, a drug evaluated in clinical trials to treat myelofibrosis, as a potent down-regulator of PNPLA3 expression, across all genotypes. We found that momelotinib treatment yielded >80% reduction in PNPLA3 mRNA in human primary hepatocytes and stellate cells, as well as in vivo via acute and chronic treatment of WT mice. Using a human multilineage 3D spheroid model of NASH homozygous for the PNPLA3 mutant protein, we additionally show that it decreases PNPLA3 mRNA as well as intracellular lipid content. Furthermore, we show that the effects on PNPLA3 coincide with changes in chromatin accessibility within regulatory regions of the PNPLA3 locus, consistent with inhibition occurring at the level of transcription. In addition to its primary reported targets, the JAK kinases, momelotinib inhibits several non-JAK kinases, including ACVR1. Using a combination of targeted siRNA knockdowns and signaling pathway perturbations, we show that momelotinib reduces the expression of the PNPLA3 gene largely through the inhibition of BMP signaling rather than the JAK/STAT pathway. Overall, our work identified momelotinib as a potential NASH therapeutic and uncovered previously unrecognized connections between signaling pathways and PNPLA3. These pathways may be exploited by drug modalities to “tune down” the level of gene expression, and therefore offer a potential therapeutic benefit to a high at-risk subset of NAFLD/NASH patients.
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Affiliation(s)
- Brian E. Schwartz
- CAMP4 Therapeutics, Cambridge, MA 02139, USA; (V.R.); (C.S.); (E.C.); (G.W.); (M.G.); (R.P.); (A.S.); (I.G.); (D.B.); (A.S.)
- Correspondence: (B.E.S.); (P.P.); Tel.: +1-617-651-8867 (B.E.S.)
| | - Vaishnavi Rajagopal
- CAMP4 Therapeutics, Cambridge, MA 02139, USA; (V.R.); (C.S.); (E.C.); (G.W.); (M.G.); (R.P.); (A.S.); (I.G.); (D.B.); (A.S.)
| | - Cynthia Smith
- CAMP4 Therapeutics, Cambridge, MA 02139, USA; (V.R.); (C.S.); (E.C.); (G.W.); (M.G.); (R.P.); (A.S.); (I.G.); (D.B.); (A.S.)
| | - Evan Cohick
- CAMP4 Therapeutics, Cambridge, MA 02139, USA; (V.R.); (C.S.); (E.C.); (G.W.); (M.G.); (R.P.); (A.S.); (I.G.); (D.B.); (A.S.)
| | - Gavin Whissell
- CAMP4 Therapeutics, Cambridge, MA 02139, USA; (V.R.); (C.S.); (E.C.); (G.W.); (M.G.); (R.P.); (A.S.); (I.G.); (D.B.); (A.S.)
| | - Mario Gamboa
- CAMP4 Therapeutics, Cambridge, MA 02139, USA; (V.R.); (C.S.); (E.C.); (G.W.); (M.G.); (R.P.); (A.S.); (I.G.); (D.B.); (A.S.)
| | - Rutuja Pai
- CAMP4 Therapeutics, Cambridge, MA 02139, USA; (V.R.); (C.S.); (E.C.); (G.W.); (M.G.); (R.P.); (A.S.); (I.G.); (D.B.); (A.S.)
| | - Alla Sigova
- CAMP4 Therapeutics, Cambridge, MA 02139, USA; (V.R.); (C.S.); (E.C.); (G.W.); (M.G.); (R.P.); (A.S.); (I.G.); (D.B.); (A.S.)
| | - Iris Grossman
- CAMP4 Therapeutics, Cambridge, MA 02139, USA; (V.R.); (C.S.); (E.C.); (G.W.); (M.G.); (R.P.); (A.S.); (I.G.); (D.B.); (A.S.)
| | - David Bumcrot
- CAMP4 Therapeutics, Cambridge, MA 02139, USA; (V.R.); (C.S.); (E.C.); (G.W.); (M.G.); (R.P.); (A.S.); (I.G.); (D.B.); (A.S.)
| | - Kavitha Sasidharan
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE-413 45 Gothenburg, Sweden; (K.S.); (S.R.)
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE-413 45 Gothenburg, Sweden; (K.S.); (S.R.)
| | - Alfica Sehgal
- CAMP4 Therapeutics, Cambridge, MA 02139, USA; (V.R.); (C.S.); (E.C.); (G.W.); (M.G.); (R.P.); (A.S.); (I.G.); (D.B.); (A.S.)
| | - Piero Pingitore
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE-413 45 Gothenburg, Sweden; (K.S.); (S.R.)
- Correspondence: (B.E.S.); (P.P.); Tel.: +1-617-651-8867 (B.E.S.)
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4
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Baselli GA, Dongiovanni P, Rametta R, Meroni M, Pelusi S, Maggioni M, Badiali S, Pingitore P, Maurotti S, Montalcini T, Taliento AE, Prati D, Rossi G, Fracanzani AL, Mancina RM, Romeo S, Valenti L. Liver transcriptomics highlights interleukin-32 as novel NAFLD-related cytokine and candidate biomarker. Gut 2020; 69:1855-1866. [PMID: 32001554 PMCID: PMC7497582 DOI: 10.1136/gutjnl-2019-319226] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 12/05/2019] [Accepted: 12/22/2019] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Efforts to manage non-alcoholic fatty liver disease (NAFLD) are limited by the incomplete understanding of the pathogenic mechanisms and the absence of accurate non-invasive biomarkers. The aim of this study was to identify novel NAFLD therapeutic targets andbiomarkers by conducting liver transcriptomic analysis in patients stratified by the presence of the PNPLA3 I148M genetic risk variant. DESIGN We sequenced the hepatic transcriptome of 125 obese individuals. 'Severe NAFLD' was defined as the presence of steatohepatitis, NAFLD activity score ≥4 or fibrosis stage ≥2. The circulating levels of the most upregulated transcript, interleukin-32 (IL32), were measured by ELISA. RESULTS Carriage of the PNPLA3 I148M variant correlated with the two major components of hepatic transcriptome variability and broadly influenced gene expression. In patients with severe NAFLD, there was an upregulation of inflammatory and lipid metabolism pathways. IL32 was the most robustly upregulated gene in the severe NAFLD group (adjusted p=1×10-6), and its expression correlated with steatosis severity, both in I148M variant carriers and non-carriers. In 77 severely obese, and in a replication cohort of 160 individuals evaluated at the hepatology service, circulating IL32 levels were associated with both NAFLD and severe NAFLD independently of aminotransferases (p<0.01 for both). A linear combination of IL32-ALT-AST showed a better performance than ALT-AST alone in NAFLD diagnosis (area under the curve=0.92 vs 0.81, p=5×10-5). CONCLUSION Hepatic IL32 is overexpressed in NAFLD, correlates with hepatic fat and liver damage, and is detectable in the circulation, where it is independently associated with the presence and severity of NAFLD.
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Affiliation(s)
- Guido Alessandro Baselli
- Department of Pathophysiology and Transplantation, Universita degli Studi di Milano, Milano, Lombardia, Italy,Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Lombardia, Italy
| | - Paola Dongiovanni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Lombardia, Italy
| | - Raffaela Rametta
- General Medicine and Metabolic Diseases, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Lombardia, Italy
| | - Marica Meroni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Lombardia, Italy
| | - Serena Pelusi
- Department of Pathophysiology and Transplantation, Universita degli Studi di Milano, Milano, Lombardia, Italy,Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Lombardia, Italy
| | - Marco Maggioni
- Pathology, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Lombardia, Italy
| | - Sara Badiali
- Surgery, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Lombardia, Italy
| | - Piero Pingitore
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University of Catanzaro, Catanzaro, Calabria, Italy
| | - Samantha Maurotti
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University of Catanzaro, Catanzaro, Calabria, Italy
| | - Tiziana Montalcini
- Department of Clinical and Experimental Medicine, Nutrition Unit, Magna Graecia University of Catanzaro, Catanzaro, Calabria, Italy
| | - Alice Emma Taliento
- Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Lombardia, Italy
| | - Daniele Prati
- Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Lombardia, Italy
| | - Giorgio Rossi
- Department of Pathophysiology and Transplantation, Universita degli Studi di Milano, Milano, Lombardia, Italy,Liver Transplantation Center, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Italy
| | - Anna Ludovica Fracanzani
- Department of Pathophysiology and Transplantation, Universita degli Studi di Milano, Milano, Lombardia, Italy,General Medicine and Metabolic Diseases, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Lombardia, Italy
| | | | - Stefano Romeo
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University of Catanzaro, Catanzaro, Calabria, Italy .,Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Cardiology Department, University of Gothenburg, Goteborg, Sweden
| | - Luca Valenti
- Department of Pathophysiology and Transplantation, Universita degli Studi di Milano, Milano, Lombardia, Italy .,Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Lombardia, Italy
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5
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Prill S, Caddeo A, Baselli G, Jamialahmadi O, Dongiovanni P, Rametta R, Kanebratt KP, Pujia A, Pingitore P, Mancina RM, Lindén D, Whatling C, Janefeldt A, Kozyra M, Ingelman-Sundberg M, Valenti L, Andersson TB, Romeo S. The TM6SF2 E167K genetic variant induces lipid biosynthesis and reduces apolipoprotein B secretion in human hepatic 3D spheroids. Sci Rep 2019; 9:11585. [PMID: 31406127 PMCID: PMC6690969 DOI: 10.1038/s41598-019-47737-w] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 07/15/2019] [Indexed: 02/08/2023] Open
Abstract
There is a high unmet need for developing treatments for nonalcoholic fatty liver disease (NAFLD), for which there are no approved drugs today. Here, we used a human in vitro disease model to understand mechanisms linked to genetic risk variants associated with NAFLD. The model is based on 3D spheroids from primary human hepatocytes from five different donors. Across these donors, we observed highly reproducible differences in the extent of steatosis induction, demonstrating that inter-donor variability is reflected in the in vitro model. Importantly, our data indicates that the genetic variant TM6SF2 E167K, previously associated with increased risk for NAFLD, induces increased hepatocyte fat content by reducing APOB particle secretion. Finally, differences in gene expression pathways involved in cholesterol, fatty acid and glucose metabolism between wild type and TM6SF2 E167K mutation carriers (N = 125) were confirmed in the in vitro model. Our data suggest that the 3D in vitro spheroids can be used to investigate the mechanisms underlying the association of human genetic variants associated with NAFLD. This model may also be suitable to discover new treatments against NAFLD.
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Affiliation(s)
- Sebastian Prill
- DMPK, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Andrea Caddeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Guido Baselli
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milano, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Oveis Jamialahmadi
- Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Paola Dongiovanni
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milano, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Raffaela Rametta
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milano, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Kajsa P Kanebratt
- DMPK, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Arturo Pujia
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, University Magna Graecia, Catanzaro, Italy
| | - Piero Pingitore
- Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden
| | | | - Daniel Lindén
- Bioscience Diabetes, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
- Division of Endocrinology, Department of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Carl Whatling
- Translational Sciences, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Annika Janefeldt
- DMPK, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Mikael Kozyra
- Department of Physiology and Pharmacology, Section of Pharmacogenetics, Karolinska Institutet, Stockholm, Sweden
| | - Magnus Ingelman-Sundberg
- Department of Physiology and Pharmacology, Section of Pharmacogenetics, Karolinska Institutet, Stockholm, Sweden
| | - Luca Valenti
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milano, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Tommy B Andersson
- DMPK, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
- Department of Physiology and Pharmacology, Section of Pharmacogenetics, Karolinska Institutet, Stockholm, Sweden
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden.
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, University Magna Graecia, Catanzaro, Italy.
- Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden.
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Caddeo A, Jamialahmadi O, Solinas G, Pujia A, Mancina RM, Pingitore P, Romeo S. MBOAT7 is anchored to endomembranes by six transmembrane domains. J Struct Biol 2019; 206:349-360. [PMID: 30959108 DOI: 10.1016/j.jsb.2019.04.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 03/17/2019] [Accepted: 04/05/2019] [Indexed: 01/08/2023]
Abstract
Membrane bound O-acyltransferase domain- containing 7 (MBOAT7, also known as LPIAT1) is a protein involved in the acyl chain remodeling of phospholipids via the Lands' cycle. The MBOAT7 is a susceptibility risk genetic locus for non-alcoholic fatty liver disease (NAFLD) and mental retardation. Although it has been shown that MBOAT7 is associated to membranes, the MBOAT7 topology remains unknown. To solve the topological organization of MBOAT7, we performed: A) solubilization of the total membrane fraction of cells overexpressing the recombinant MBOAT7-V5, which revealed MBOAT7 is an integral protein strongly attached to endomembranes; B) in silico analysis by using 22 computational methods, which predicted the number and localization of transmembrane domains of MBOAT7 with a range between 5 and 12; C) in vitro analysis of living cells transfected with GFP-tagged MBOAT7 full length and truncated forms, using a combination of Western Blotting, co-immunofluorescence and Fluorescence Protease Protection (FPP) assay; D) in vitro analysis of living cells transfected with FLAG-tagged MBOAT7 full length forms, using a combination of Western Blotting, selective membrane permeabilization followed by indirect immunofluorescence. All together, these data revealed that MBOAT7 is a multispanning transmembrane protein with six transmembrane domains. Based on our model, the predicted catalytic dyad of the protein, composed of the conserved asparagine in position 321 (Asn-321) and the preserved histidine in position 356 (His-356), has a lumenal localization. These data are compatible with the role of MBOAT7 in remodeling the acyl chain composition of endomembranes.
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Affiliation(s)
- Andrea Caddeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE 41345, Sweden
| | - Oveis Jamialahmadi
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE 41345, Sweden; Biotechnology Group, Faculty of Chemical Engineering, Tarbiat Modares University, Tehran, Iran
| | - Giovanni Solinas
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE 41345, Sweden
| | - Arturo Pujia
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | | | - Piero Pingitore
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE 41345, Sweden
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE 41345, Sweden; Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy; Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden.
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Pingitore P, Sasidharan K, Ekstrand M, Prill S, Lindén D, Romeo S. Human Multilineage 3D Spheroids as a Model of Liver Steatosis and Fibrosis. Int J Mol Sci 2019; 20:ijms20071629. [PMID: 30986904 PMCID: PMC6480107 DOI: 10.3390/ijms20071629] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 03/29/2019] [Accepted: 03/30/2019] [Indexed: 02/06/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the most common liver disorder in western countries. Despite the high prevalence of NAFLD, the underlying biology of the disease progression is not clear, and there are no approved drugs to treat non-alcoholic steatohepatitis (NASH), the most advanced form of the disease. Thus, there is an urgent need for developing advanced in vitro human cellular systems to study disease mechanisms and drug responses. We attempted to create an organoid system genetically predisposed to NAFLD and to induce steatosis and fibrosis in it by adding free fatty acids. We used multilineage 3D spheroids composed by hepatocytes (HepG2) and hepatic stellate cells (LX-2) with a physiological ratio (24:1). HepG2 and LX-2 cells are homozygotes for the PNPLA3 I148M sequence variant, the strongest genetic determinant of NAFLD. We demonstrate that hepatic stellate cells facilitate the compactness of 3D spheroids. Then, we show that the spheroids develop accumulations of fat and collagen upon exposure to free fatty acids. Finally, this accumulation was rescued by incubating spheroids with liraglutide or elafibranor, drugs that are in clinical trials for the treatment of NASH. In conclusion, we have established a simple, easy to handle, in vitro model of genetically induced NAFLD consisting of multilineage 3D spheroids. This tool may be used to understand molecular mechanisms involved in the early stages of fibrogenesis induced by lipid accumulation. Moreover, it may be used to identify new compounds to treat NASH using high-throughput drug screening.
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Affiliation(s)
- Piero Pingitore
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE-413 45 Gothenburg, Sweden.
| | - Kavitha Sasidharan
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE-413 45 Gothenburg, Sweden.
| | - Matias Ekstrand
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE-413 45 Gothenburg, Sweden.
| | - Sebastian Prill
- Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, SE-431 83 Gothenburg, Sweden.
| | - Daniel Lindén
- Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, SE-431 83 Gothenburg, Sweden.
- Division of Endocrinology, Department of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, SE-405 30 Gothenburg, Sweden.
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, SE-413 45 Gothenburg, Sweden.
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, 88100 Catanzaro, Italy.
- Cardiology Department, Sahlgrenska University Hospital, SE-413 45 Gothenburg, Sweden.
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8
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Botta M, Maurer E, Ruscica M, Romeo S, Stulnig TM, Pingitore P. Deciphering the role of V200A and N291S mutations leading to LPL deficiency. Atherosclerosis 2019; 282:45-51. [DOI: 10.1016/j.atherosclerosis.2019.01.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 12/19/2018] [Accepted: 01/09/2019] [Indexed: 11/25/2022]
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9
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Lindén D, Ahnmark A, Pingitore P, Ciociola E, Ahlstedt I, Andréasson AC, Sasidharan K, Madeyski-Bengtson K, Zurek M, Mancina RM, Lindblom A, Bjursell M, Böttcher G, Ståhlman M, Bohlooly-Y M, Haynes WG, Carlsson B, Graham M, Lee R, Murray S, Valenti L, Bhanot S, Åkerblad P, Romeo S. Pnpla3 silencing with antisense oligonucleotides ameliorates nonalcoholic steatohepatitis and fibrosis in Pnpla3 I148M knock-in mice. Mol Metab 2019; 22:49-61. [PMID: 30772256 PMCID: PMC6437635 DOI: 10.1016/j.molmet.2019.01.013] [Citation(s) in RCA: 129] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Revised: 01/22/2019] [Accepted: 01/30/2019] [Indexed: 01/18/2023] Open
Abstract
Objective Nonalcoholic fatty liver disease (NAFLD) is becoming a leading cause of advanced chronic liver disease. The progression of NAFLD, including nonalcoholic steatohepatitis (NASH), has a strong genetic component, and the most robust contributor is the patatin-like phospholipase domain-containing 3 (PNPLA3) rs738409 encoding the 148M protein sequence variant. We hypothesized that suppressing the expression of the PNPLA3 148M mutant protein would exert a beneficial effect on the entire spectrum of NAFLD. Methods We examined the effects of liver-targeted GalNAc3-conjugated antisense oligonucleotide (ASO)-mediated silencing of Pnpla3 in a knock-in mouse model in which we introduced the human PNPLA3 I148M mutation. Results ASO-mediated silencing of Pnpla3 reduced liver steatosis (p = 0.038) in homozygous Pnpla3 148M/M knock-in mutant mice but not in wild-type littermates fed a steatogenic high-sucrose diet. In mice fed a NASH-inducing diet, ASO-mediated silencing of Pnpla3 reduced liver steatosis score and NAFLD activity score independent of the Pnpla3 genotype, while reductions in liver inflammation score (p = 0.018) and fibrosis stage (p = 0.031) were observed only in the Pnpla3 knock-in 148M/M mutant mice. These responses were accompanied by reduced liver levels of Mcp1 (p = 0.026) and Timp2 (p = 0.007) specifically in the mutant knock-in mice. This may reduce levels of chemokine attracting inflammatory cells and increase the collagenolytic activity during tissue regeneration. Conclusion This study provides the first evidence that a Pnpla3 ASO therapy can improve all features of NAFLD, including liver fibrosis, and suppress the expression of a strong innate genetic risk factor, Pnpla3 148M, which may open up a precision medicine approach in NASH. ASO-mediated silencing of Pnpla3 reduced liver steatosis specifically in homozygous Pnpla3 148M/M mice fed a high-sucrose diet. In mice fed a NASH-inducing diet this treatment reduced liver inflammation and fibrosis specifically in the Pnpla3 148M/M mutant mice. This is the first proof of concept of a NASH precision medicine treatment exploiting an innate genetic risk variant for the disease.
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Affiliation(s)
- Daniel Lindén
- Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden; Division of Endocrinology, Department of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Sweden.
| | - Andrea Ahnmark
- Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Piero Pingitore
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - Ester Ciociola
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - Ingela Ahlstedt
- Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | | | - Kavitha Sasidharan
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - Katja Madeyski-Bengtson
- Translational Genomics, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Magdalena Zurek
- Drug Safety & Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Rosellina M Mancina
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - Anna Lindblom
- Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Mikael Bjursell
- Translational Genomics, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Gerhard Böttcher
- Drug Safety & Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Marcus Ståhlman
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - Mohammad Bohlooly-Y
- Translational Genomics, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - William G Haynes
- Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Björn Carlsson
- Cardiovascular, Renal and Metabolism Translational Medicine Unit, Early Clinical Development, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | | | | | | | - Luca Valenti
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milano, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | | | - Peter Åkerblad
- Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden; Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy; Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden.
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10
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Pingitore P, Romeo S. The role of PNPLA3 in health and disease. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:900-906. [PMID: 29935383 DOI: 10.1016/j.bbalip.2018.06.018] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 06/12/2018] [Accepted: 06/14/2018] [Indexed: 01/04/2023]
Abstract
The human patatin-like phospholipase domain-containing 3 (PNPLA3) gene encodes for a protein of 481 amino-acids. The variant rs738409 is a cytosine to guanine substitution, encoding for the isoleucine to methionine substitution at position 148 (I148M) of the protein. This variant is strongly associated with the entire spectrum of liver disease. Although this variant is one of the best characterized and deeply studied, the mechanism behind the PNPLA3 and the liver disease is still not well defined. Functionally, it has become clear that the PNPLA3 protein is an enzyme with lipase activity towards triglycerides and retinyl esters, and acyltransferase activity on phospholipids. The aim of this review is to collect the latest data, obtained by in vitro and in vivo experiments, on the functional aspects of the PNPLA3 protein. Defining the precise role of PNPLA3 in the liver lipid metabolism, in order to develop novel therapies for the treatment of liver disease, will be the key of future research.
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Affiliation(s)
- Piero Pingitore
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden; Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden; Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy.
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11
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Dongiovanni P, Stender S, Pietrelli A, Mancina RM, Cespiati A, Petta S, Pelusi S, Pingitore P, Badiali S, Maggioni M, Mannisto V, Grimaudo S, Pipitone RM, Pihlajamaki J, Craxi A, Taube M, Carlsson LMS, Fargion S, Romeo S, Kozlitina J, Valenti L. Causal relationship of hepatic fat with liver damage and insulin resistance in nonalcoholic fatty liver. J Intern Med 2018; 283:356-370. [PMID: 29280273 PMCID: PMC5900872 DOI: 10.1111/joim.12719] [Citation(s) in RCA: 230] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND AND AIMS Nonalcoholic fatty liver disease is epidemiologically associated with hepatic and metabolic disorders. The aim of this study was to examine whether hepatic fat accumulation has a causal role in determining liver damage and insulin resistance. METHODS We performed a Mendelian randomization analysis using risk alleles in PNPLA3, TM6SF2, GCKR and MBOAT7, and a polygenic risk score for hepatic fat, as instruments. We evaluated complementary cohorts of at-risk individuals and individuals from the general population: 1515 from the liver biopsy cohort (LBC), 3329 from the Swedish Obese Subjects Study (SOS) and 4570 from the population-based Dallas Heart Study (DHS). RESULTS Hepatic fat was epidemiologically associated with liver damage, insulin resistance, dyslipidemia and hypertension. The impact of genetic variants on liver damage was proportional to their effect on hepatic fat accumulation. Genetically determined hepatic fat was associated with aminotransferases, and with inflammation, ballooning and fibrosis in the LBC. Furthermore, in the LBC, the causal association between hepatic fat and fibrosis was independent of disease activity, suggesting that a causal effect of long-term liver fat accumulation on liver disease is independent of inflammation. Genetically determined hepatic steatosis was associated with insulin resistance in the LBC and SOS. However, this association was dependent on liver damage severity. Genetically determined hepatic steatosis was associated with liver fibrosis/cirrhosis and with a small increase in risk of type 2 diabetes in publicly available databases. CONCLUSION These data suggest that long-term hepatic fat accumulation plays a causal role in the development of chronic liver disease.
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Affiliation(s)
- P Dongiovanni
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milan, Italy
| | - S Stender
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - A Pietrelli
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milan, Italy.,Bioinformatic unit, Istituto Nazionale Genetica Molecolare, Milan, Italy
| | - R M Mancina
- Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden
| | - A Cespiati
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milan, Italy
| | - S Petta
- Department of Gastroenterology, Università di Palermo, Palermo, Italy
| | - S Pelusi
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milan, Italy
| | - P Pingitore
- Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden
| | - S Badiali
- Department of Surgery, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milan, Italy
| | - M Maggioni
- Department of Pathology, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milan, Italy
| | - V Mannisto
- Department of Gastroenterology, University of Eastern Finland, Kuopio University Hospital, Kuopio, Finland
| | - S Grimaudo
- Department of Gastroenterology, Università di Palermo, Palermo, Italy
| | - R M Pipitone
- Department of Gastroenterology, Università di Palermo, Palermo, Italy
| | - J Pihlajamaki
- Department of Medicine, University of Eastern Finland, Kuopio University Hospital, Kuopio, Finland.,Clinical Nutrition and Obesity Center, Kuopio University Hospital, Kuopio, Finland.,Department of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
| | - A Craxi
- Department of Gastroenterology, Università di Palermo, Palermo, Italy
| | - M Taube
- Department of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
| | - L M S Carlsson
- Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - S Fargion
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milan, Italy.,Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - S Romeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden.,Clinical Nutrition Unit, Department of Medical and Surgical Sciences, University Magna Graecia, Catanzaro, Italy.,Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - J Kozlitina
- McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - L Valenti
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milan, Italy.,Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
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12
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Affiliation(s)
| | - Piero Pingitore
- University of Gothenburg, Sweden Department of Molecular and Clinical Medicine
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13
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Caddeo A, Mancina RM, Pirazzi C, Russo C, Sasidharan K, Sandstedt J, Maurotti S, Montalcini T, Pujia A, Leren TP, Romeo S, Pingitore P. Molecular analysis of three known and one novel LPL variants in patients with type I hyperlipoproteinemia. Nutr Metab Cardiovasc Dis 2018; 28:158-164. [PMID: 29288010 DOI: 10.1016/j.numecd.2017.11.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 10/19/2017] [Accepted: 11/13/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND AND AIMS Type I hyperlipoproteinemia, also known as familial chylomicronemia syndrome (FCS), is a rare autosomal recessive disorder caused by variants in LPL, APOC2, APOA5, LMF1 or GPIHBP1 genes. The aim of this study was to identify novel variants in the LPL gene causing lipoprotein lipase deficiency and to understand the molecular mechanisms. METHODS AND RESULTS A total of 3 individuals with severe hypertriglyceridemia and recurrent pancreatitis were selected from the Lipid Clinic at Sahlgrenska University Hospital and LPL was sequenced. In vitro experiments were performed in human embryonic kidney 293T/17 (HEK293T/17) cells transiently transfected with wild type or mutant LPL plasmids. Cell lysates and media were used to analyze LPL synthesis and secretion. Media were used to measure LPL activity. Patient 1 was compound heterozygous for three known variants: c.337T > C (W113R), c.644G > A (G215E) and c.1211T > G (M404R); patient 2 was heterozygous for the known variant c.658A > C (S220R) while patient 3 was homozygous for a novel variant in the exon 5 c.679G > T (V227F). All the LPL variants identified were loss-of-function variants and resulted in a substantial reduction in the secretion of LPL protein. CONCLUSION We characterized at the molecular level three known and one novel LPL variants causing type I hyperlipoproteinemia showing that all these variants are pathogenic.
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Affiliation(s)
- A Caddeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - R M Mancina
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - C Pirazzi
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden; Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - C Russo
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - K Sasidharan
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - J Sandstedt
- Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden; Department of Clinical Chemistry, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - S Maurotti
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - T Montalcini
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - A Pujia
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - T P Leren
- Unit for Cardiac and Cardiovascular Genetics, Department of Medical Genetics, Oslo University Hospital Ullevaal, Oslo, Norway
| | - S Romeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden; Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden; Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy.
| | - P Pingitore
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden.
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14
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Pingitore P, Dongiovanni P, Motta BM, Meroni M, Lepore SM, Mancina RM, Pelusi S, Russo C, Caddeo A, Rossi G, Montalcini T, Pujia A, Wiklund O, Valenti L, Romeo S. PNPLA3 overexpression results in reduction of proteins predisposing to fibrosis. Hum Mol Genet 2017; 25:5212-5222. [PMID: 27742777 PMCID: PMC5886043 DOI: 10.1093/hmg/ddw341] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 09/28/2016] [Indexed: 01/22/2023] Open
Abstract
Liver fibrosis is a pathological scarring response to chronic hepatocellular injury and hepatic stellate cells (HSCs) are key players in this process. PNPLA3 I148M is a common variant robustly associated with liver fibrosis but the mechanisms underlying this association are unknown. We aimed to examine a) the effect of fibrogenic and proliferative stimuli on PNPLA3 levels in HSCs and b) the role of wild type and mutant PNPLA3 overexpression on markers of HSC activation and fibrosis. Here, we show that PNPLA3 is upregulated by the fibrogenic cytokine transforming growth factor-beta (TGF-β), but not by platelet-derived growth factor (PDGF), and is involved in the TGF-β-induced reduction in lipid droplets in primary human HSCs. Furthermore, we show that retinol release from human HSCs ex vivo is lower in cells with the loss-of-function PNPLA3 148M compared with 148I wild type protein. Stable overexpression of PNPLA3 148I wild type, but not 148M mutant, in human HSCs (LX-2 cells) induces a reduction in the secretion of matrix metallopeptidase 2 (MMP2), tissue inhibitor of metalloproteinase 1 and 2 (TIMP1 and TIMP2), which is mediated by retinoid metabolism. In conclusion, we show a role for PNPLA3 in HSC activation in response to fibrogenic stimuli. Moreover, we provide evidence to indicate that PNPLA3-mediated retinol release may protect against liver fibrosis by inducing a specific signature of proteins involved in extracellular matrix remodelling.
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Affiliation(s)
- Piero Pingitore
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - Paola Dongiovanni
- Internal Medicine, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milan, Italy
| | | | - Marica Meroni
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Saverio Massimo Lepore
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | | | - Serena Pelusi
- Internal Medicine, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milan, Italy
| | - Cristina Russo
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Andrea Caddeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - Giorgio Rossi
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy.,Liver Surgery and Transplant Unit, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milan, Italy
| | - Tiziana Montalcini
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Arturo Pujia
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Olov Wiklund
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden.,Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Luca Valenti
- Internal Medicine, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milan, Italy.,Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden.,Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy.,Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden
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15
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Lind U, Järvå M, Alm Rosenblad M, Pingitore P, Karlsson E, Wrange AL, Kamdal E, Sundell K, André C, Jonsson PR, Havenhand J, Eriksson LA, Hedfalk K, Blomberg A. Analysis of aquaporins from the euryhaline barnacle Balanus improvisus reveals differential expression in response to changes in salinity. PLoS One 2017; 12:e0181192. [PMID: 28715506 PMCID: PMC5513457 DOI: 10.1371/journal.pone.0181192] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 06/26/2017] [Indexed: 12/13/2022] Open
Abstract
Barnacles are sessile macro-invertebrates, found along rocky shores in coastal areas worldwide. The euryhaline bay barnacle Balanus improvisus (Darwin, 1854) (= Amphibalanus improvisus) can tolerate a wide range of salinities, but the molecular mechanisms underlying the osmoregulatory capacity of this truly brackish species are not well understood. Aquaporins are pore-forming integral membrane proteins that facilitate transport of water, small solutes and ions through cellular membranes, and that have been shown to be important for osmoregulation in many organisms. The knowledge of the function of aquaporins in crustaceans is, however, limited and nothing is known about them in barnacles. We here present the repertoire of aquaporins from a thecostracan crustacean, the barnacle B. improvisus, based on genome and transcriptome sequencing. Our analyses reveal that B. improvisus contains eight genes for aquaporins. Phylogenetic analysis showed that they represented members of the classical water aquaporins (Aqp1, Aqp2), the aquaglyceroporins (Glp1, Glp2), the unorthodox aquaporin (Aqp12) and the arthropod-specific big brain aquaporin (Bib). Interestingly, we also found two big brain-like proteins (BibL1 and BibL2) constituting a new group of aquaporins not yet described in arthropods. In addition, we found that the two water-specific aquaporins were expressed as C-terminal splice variants. Heterologous expression of some of the aquaporins followed by functional characterization showed that Aqp1 transported water and Glp2 water and glycerol, agreeing with the predictions of substrate specificity based on 3D modeling and phylogeny. To investigate a possible role for the B. improvisus aquaporins in osmoregulation, mRNA expression changes in adult barnacles were analysed after long-term acclimation to different salinities. The most pronounced expression difference was seen for AQP1 with a substantial (>100-fold) decrease in the mantle tissue in low salinity (3 PSU) compared to high salinity (33 PSU). Our study provides a base for future mechanistic studies on the role of aquaporins in osmoregulation.
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Affiliation(s)
- Ulrika Lind
- Department of Marine Sciences, Lundberg laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Michael Järvå
- Department of Chemistry and Molecular Biology, Lundberg laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Magnus Alm Rosenblad
- Department of Marine Sciences, National Infrastructure of Bioinformatics (NBIS), Lundberg laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Piero Pingitore
- Department of Molecular and Clinical Medicine, Wallenberg Laboratory, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Emil Karlsson
- Department of Marine Sciences, Lundberg laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Anna-Lisa Wrange
- RISE Research Institute of Sweden, Section for Chemistry and Materials, Borås, Sweden
| | - Emelie Kamdal
- Department of Chemistry and Molecular Biology, Lundberg laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Kristina Sundell
- Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Carl André
- Department of Marine Sciences-Tjärnö, University of Gothenburg, Strömstad, Sweden
| | - Per R. Jonsson
- Department of Marine Sciences-Tjärnö, University of Gothenburg, Strömstad, Sweden
| | - Jon Havenhand
- Department of Marine Sciences-Tjärnö, University of Gothenburg, Strömstad, Sweden
| | - Leif A. Eriksson
- Department of Chemistry and Molecular Biology, Lundberg laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Kristina Hedfalk
- Department of Chemistry and Molecular Biology, Lundberg laboratory, University of Gothenburg, Gothenburg, Sweden
| | - Anders Blomberg
- Department of Marine Sciences, Lundberg laboratory, University of Gothenburg, Gothenburg, Sweden
- * E-mail:
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16
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Donati B, Pietrelli A, Pingitore P, Dongiovanni P, Caddeo A, Walker L, Baselli G, Pelusi S, Rosso C, Vanni E, Daly A, Mancina RM, Grieco A, Miele L, Grimaudo S, Craxi A, Petta S, De Luca L, Maier S, Soardo G, Bugianesi E, Colli F, Romagnoli R, Anstee QM, Reeves HL, Fracanzani AL, Fargion S, Romeo S, Valenti L. Telomerase reverse transcriptase germline mutations and hepatocellular carcinoma in patients with nonalcoholic fatty liver disease. Cancer Med 2017; 6:1930-1940. [PMID: 28677271 PMCID: PMC5548883 DOI: 10.1002/cam4.1078] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Revised: 03/25/2017] [Accepted: 03/27/2017] [Indexed: 12/18/2022] Open
Abstract
In an increasing proportion of cases, hepatocellular carcinoma (HCC) develops in patients with nonalcoholic fatty liver disease (NAFLD). Mutations in telomerase reverse transcriptase (hTERT) are associated with familial liver diseases. The aim of this study was to examine telomere length and germline hTERT mutations as associated with NAFLD‐HCC. In 40 patients with NAFLD‐HCC, 45 with NAFLD‐cirrhosis and 64 healthy controls, peripheral blood telomere length was evaluated by qRT‐PCR and hTERT coding regions and intron–exon boundaries sequenced. We further analyzed 78 patients affected by primary liver cancer (NAFLD‐PLC, 76 with HCC). Enrichment of rare coding mutations (allelic frequency <0.001) was evaluated by Burden test. Functional consequences were estimated in silico and by over‐expressing protein variants in HEK‐293 cells. We found that telomere length was reduced in individuals with NAFLD‐HCC versus those with cirrhosis (P = 0.048) and healthy controls (P = 0.0006), independently of age and sex. We detected an enrichment of hTERT mutations in NAFLD‐HCC, that was confirmed when we further considered a larger cohort of NAFLD‐PLC, and was more marked in female patients (P = 0.03). No mutations were found in cirrhosis and local controls, and only one in 503 healthy Europeans from the 1000 Genomes Project (allelic frequency = 0.025 vs. <0.001; P = 0.0005). Mutations with predicted functional impact, including the frameshift Glu113Argfs*79 and missense Glu668Asp, cosegregated with liver disease in two families. Three patients carried missense mutations (Ala67Val in homozygosity, Pro193Leu and His296Pro in heterozygosity) in the N‐terminal template‐binding domain (P = 0.037 for specific enrichment). Besides Glu668Asp, the Ala67Val variant resulted in reduced intracellular protein levels. In conclusion, we detected an association between shorter telomeres in peripheral blood and rare germline hTERT mutations and NAFLD‐HCC.
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Affiliation(s)
- Benedetta Donati
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, 20122, Italy
| | - Alessandro Pietrelli
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, 20122, Italy.,Istituto Nazionale di Genetica Molecolare (INGM), Romeo ed Enrica Invernizzi, Bioinformatics Group, Milan, 20122, Italy
| | - Piero Pingitore
- Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, SE-405 30, Sweden
| | - Paola Dongiovanni
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, 20122, Italy
| | - Andrea Caddeo
- Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, SE-405 30, Sweden
| | - Lucy Walker
- The Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE7 7DN, United Kingdom
| | - Guido Baselli
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, 20122, Italy
| | - Serena Pelusi
- Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, 20122, Italy
| | - Chiara Rosso
- Division of Gastroenterology, Department of Medical Sciences, University of Torino, Torino, 10126, Italy
| | - Ester Vanni
- Division of Gastroenterology, Department of Medical Sciences, University of Torino, Torino, 10126, Italy
| | - Ann Daly
- The Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE7 7DN, United Kingdom
| | - Rosellina Margherita Mancina
- Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, SE-405 30, Sweden
| | - Antonio Grieco
- Internal Medicine and Gastroenterology Area, Fondazione Policlinico Universitario A. Gemelli, Catholic University of Rome, Rome, 00168, Italy
| | - Luca Miele
- Internal Medicine and Gastroenterology Area, Fondazione Policlinico Universitario A. Gemelli, Catholic University of Rome, Rome, 00168, Italy
| | - Stefania Grimaudo
- Section of Gastroenterology, DIBIMIS, University of Palermo, Palermo, 90127, Italy
| | - Antonio Craxi
- Section of Gastroenterology, DIBIMIS, University of Palermo, Palermo, 90127, Italy
| | - Salvatore Petta
- Section of Gastroenterology, DIBIMIS, University of Palermo, Palermo, 90127, Italy
| | - Laura De Luca
- Clinic of Internal Medicine-Liver Unit, Department of Experimental and Clinical Medical Sciences, University of Udine, Udine, 33100, Italy
| | - Silvia Maier
- Clinic of Internal Medicine-Liver Unit, Department of Experimental and Clinical Medical Sciences, University of Udine, Udine, 33100, Italy
| | - Giorgio Soardo
- Clinic of Internal Medicine-Liver Unit, Department of Experimental and Clinical Medical Sciences, University of Udine, Udine, 33100, Italy
| | - Elisabetta Bugianesi
- Division of Gastroenterology, Department of Medical Sciences, University of Torino, Torino, 10126, Italy
| | - Fabio Colli
- Department of Surgical Sciences, Liver Transplantation Center, University of Torino, Torino, 10126, Italy
| | - Renato Romagnoli
- Department of Surgical Sciences, Liver Transplantation Center, University of Torino, Torino, 10126, Italy
| | - Quentin M Anstee
- The Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE7 7DN, United Kingdom.,Liver Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, NE2 4HH, United Kingdom
| | - Helen L Reeves
- The Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE7 7DN, United Kingdom.,Northern Institute for Cancer Research, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, United Kingdom
| | - Anna Ludovica Fracanzani
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, 20122, Italy.,Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, 20122, Italy
| | - Silvia Fargion
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, 20122, Italy.,Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, 20122, Italy
| | - Stefano Romeo
- Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, SE-405 30, Sweden.,Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, 88100, Italy
| | - Luca Valenti
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, 20122, Italy.,Internal Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, 20122, Italy
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17
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Russo C, Lazzaro V, Gazzaruso C, Maurotti S, Ferro Y, Pingitore P, Fumo F, Coppola A, Gallotti P, Zambianchi V, Fodaro M, Galliera E, Marazzi MG, Corsi Romanelli MM, Giannini S, Romeo S, Pujia A, Montalcini T. Proinsulin C-peptide modulates the expression of ERK1/2, type I collagen and RANKL in human osteoblast-like cells (Saos-2). Mol Cell Endocrinol 2017; 442:134-141. [PMID: 28007656 DOI: 10.1016/j.mce.2016.12.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 12/07/2016] [Accepted: 12/12/2016] [Indexed: 12/29/2022]
Abstract
A lower bone mass accompanied by a higher bone fragility with increased risk of fracture are observed in individuals with type 1 diabetes mellitus. Low C-peptide levels are associated with low lumbar mineral density in postmenopausal woman. In this work, we investigated the role of C-peptide on the osteoblast cell biology in vitro. We examined intracellular pathways and we found that C peptide activates ERK1/2 in human osteoblast-like cells (Saos-2). We also observed that proinsulin C-peptide prevents a reduction of type I collagen expression and decreases, in combination with insulin, receptor activator of nuclear factor-κB (RANKL) levels. In this work we show for the first time that Cpeptide activates a specific intracellular pathway in osteoblasts and it modulates the expression of protein involved in bone remodeling. Our results suggest that both C-peptide may have a role in bone metabolism. Further studies are needing to fully clarify its role.
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Affiliation(s)
- Cristina Russo
- Department of Medical and Surgical Sciences, University "Magna Graecia" of Catanzaro, Catanzaro, Italy
| | - Veronica Lazzaro
- Department of Health Sciences, University "Magna Graecia" of Catanzaro, Catanzaro, Italy
| | - Carmine Gazzaruso
- Internal and Emergency Medicine, and Ce.R.C.A. Clinical Institute "Beato Matteo", Vigevano, Italy
| | - Samantha Maurotti
- Department of Medical and Surgical Sciences, University "Magna Graecia" of Catanzaro, Catanzaro, Italy
| | - Yvelise Ferro
- Department of Medical and Surgical Sciences, University "Magna Graecia" of Catanzaro, Catanzaro, Italy
| | - Piero Pingitore
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - Francesca Fumo
- Department of Medical and Surgical Sciences, University "Magna Graecia" of Catanzaro, Catanzaro, Italy
| | - Adriana Coppola
- Internal and Emergency Medicine, and Ce.R.C.A. Clinical Institute "Beato Matteo", Vigevano, Italy
| | - Pietro Gallotti
- Internal and Emergency Medicine, and Ce.R.C.A. Clinical Institute "Beato Matteo", Vigevano, Italy
| | - Valentina Zambianchi
- Internal and Emergency Medicine, and Ce.R.C.A. Clinical Institute "Beato Matteo", Vigevano, Italy
| | - Mariangela Fodaro
- Internal and Emergency Medicine, and Ce.R.C.A. Clinical Institute "Beato Matteo", Vigevano, Italy
| | - Emanuela Galliera
- Department of Biomedical, Surgical and Dental Science, University of Milan, Italy
| | | | | | - Sandro Giannini
- Department of Medical and Surgical Sciences, University of Padova, Italy
| | - Stefano Romeo
- Department of Medical and Surgical Sciences, University "Magna Graecia" of Catanzaro, Catanzaro, Italy; Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - Arturo Pujia
- Department of Medical and Surgical Sciences, University "Magna Graecia" of Catanzaro, Catanzaro, Italy
| | - Tiziana Montalcini
- Department of Clinical and Experimental Medicine, University "Magna Graecia" of Catanzaro, Italy.
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18
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Pingitore P, Lepore S, Pirazzi C, Mancina R, Motta B, Valenti L, Berge K, Retterstøl K, Leren T, Wiklund O, Romeo S. Identification and characterization of two novel mutations in the LPL gene causing type I hyperlipoproteinemia. Atherosclerosis 2016. [DOI: 10.1016/j.atherosclerosis.2016.07.477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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19
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Mancina RM, Dongiovanni P, Petta S, Pingitore P, Meroni M, Rametta R, Borén J, Montalcini T, Pujia A, Wiklund O, Hindy G, Spagnuolo R, Motta BM, Pipitone RM, Craxì A, Fargion S, Nobili V, Käkelä P, Kärjä V, Männistö V, Pihlajamäki J, Reilly DF, Castro-Perez J, Kozlitina J, Valenti L, Romeo S. The MBOAT7-TMC4 Variant rs641738 Increases Risk of Nonalcoholic Fatty Liver Disease in Individuals of European Descent. Gastroenterology 2016; 150:1219-1230.e6. [PMID: 26850495 PMCID: PMC4844071 DOI: 10.1053/j.gastro.2016.01.032] [Citation(s) in RCA: 441] [Impact Index Per Article: 55.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 01/26/2016] [Accepted: 01/26/2016] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS Nonalcoholic fatty liver disease (NAFLD) is a leading cause of liver damage and is characterized by steatosis. Genetic factors increase risk for progressive NAFLD. A genome-wide association study showed that the rs641738 C>T variant in the locus that contains the membrane bound O-acyltransferase domain-containing 7 gene (MBOAT7, also called LPIAT1) and transmembrane channel-like 4 gene (TMC4) increased the risk for cirrhosis in alcohol abusers. We investigated whether the MBOAT7-TMC4 is a susceptibility locus for the development and progression of NAFLD. METHODS We genotyped rs641738 in DNA collected from 3854 participants from the Dallas Heart Study (a multi-ethnic population-based probability sample of Dallas County residents) and 1149 European individuals from the Liver Biopsy Cross-Sectional Cohort. Clinical and anthropometric data were collected, and biochemical and lipidomics were measured in plasma samples from participants. A total of 2736 participants from the Dallas Heart Study also underwent proton magnetic resonance spectroscopy to measure hepatic triglyceride content. In the Liver Biopsy Cross-Sectional Cohort, a total of 1149 individuals underwent liver biopsy to diagnose liver disease and disease severity. RESULTS The genotype rs641738 at the MBOAT7-TMC4 locus associated with increased hepatic fat content in the 2 cohorts, and with more severe liver damage and increased risk of fibrosis compared with subjects without the variant. MBOAT7, but not TMC4, was found to be highly expressed in the liver. The MBOAT7 rs641738 T allele was associated with lower protein expression in the liver and changes in plasma phosphatidylinositol species consistent with decreased MBOAT7 function. CONCLUSIONS We provide evidence for an association between the MBOAT7 rs641738 variant and the development and severity of NAFLD in individuals of European descent. This association seems to be mediated by changes in the hepatic phosphatidylinositol acyl-chain remodeling.
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Affiliation(s)
| | - Paola Dongiovanni
- Internal Medicine, Fondazione IRCCS Ca’ Granda Ospedale Policlinico Milano, Milan, Italy
| | - Salvatore Petta
- Department of Gastroenterology, Università di Palermo, Palermo, Italy
| | - Piero Pingitore
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - Marica Meroni
- Department of Pathophysiology and Transplantation Università degli Studi di Milano, Milan, Italy
| | - Raffaela Rametta
- Department of Pathophysiology and Transplantation Università degli Studi di Milano, Milan, Italy
| | - Jan Borén
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden
| | - Tiziana Montalcini
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, University Magna Graecia, Catanzaro, Italy
| | - Arturo Pujia
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, University Magna Graecia, Catanzaro, Italy
| | - Olov Wiklund
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden,Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - George Hindy
- Diabetes and Cardiovascular Disease-Genetic Epidemiology, Lund, Sweden
| | - Rocco Spagnuolo
- Division of Gastroenterology, Fondazione Tommaso Campanella, University Magna Graecia of Catanzaro, Italy
| | | | - Rosaria Maria Pipitone
- Department of Pathophysiology and Transplantation Università degli Studi di Milano, Milan, Italy
| | - Antonio Craxì
- Department of Gastroenterology, Università di Palermo, Palermo, Italy
| | - Silvia Fargion
- Internal Medicine, Fondazione IRCCS Ca’ Granda Ospedale Policlinico Milano, Milan, Italy,Department of Pathophysiology and Transplantation Università degli Studi di Milano, Milan, Italy
| | | | - Pirjo Käkelä
- Department of Surgery, University of Eastern Finland and Kuopio University Hospital, Kuopio, Finland
| | - Vesa Kärjä
- Department of Pathology, University of Eastern Finland and Kuopio University Hospital, Kuopio, Finland
| | - Ville Männistö
- Department of Medicine, University of Eastern Finland and Kuopio University Hospital, Kuopio, Finland
| | - Jussi Pihlajamäki
- Clinical Nutrition and Obesity Center, Kuopio University Hospital, Kuopio, Finland,Department of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
| | - Dermot F. Reilly
- Merck Research Laboratories, Genetics and Pharmacogenomics, Boston, Massachusetts, USA
| | - Jose Castro-Perez
- Merck Research Laboratories, Diabetes Department, Kenilworth, New Jersey, USA,Waters Corporation, Milford, Massachusetts, USA
| | - Julia Kozlitina
- McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, Texas.
| | - Luca Valenti
- Internal Medicine, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milan, Italy; Department of Pathophysiology and Transplantationm Università degli Studi di Milano, Milan, Italy.
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, Sweden; Clinical Nutrition Unit, Department of Medical and Surgical Sciences, University Magna Graecia, Catanzaro, Italy; Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden.
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20
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Pingitore P, Lepore SM, Pirazzi C, Mancina RM, Motta BM, Valenti L, Berge KE, Retterstøl K, Leren TP, Wiklund O, Romeo S. Identification and characterization of two novel mutations in the LPL gene causing type I hyperlipoproteinemia. J Clin Lipidol 2016; 10:816-823. [PMID: 27578112 DOI: 10.1016/j.jacl.2016.02.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 02/28/2016] [Indexed: 11/25/2022]
Abstract
BACKGROUND Type 1 hyperlipoproteinemia is a rare autosomal recessive disorder most often caused by mutations in the lipoprotein lipase (LPL) gene resulting in severe hypertriglyceridemia and pancreatitis. OBJECTIVES The aim of this study was to identify novel mutations in the LPL gene causing type 1 hyperlipoproteinemia and to understand the molecular mechanisms underlying the severe hypertriglyceridemia. METHODS Three patients presenting classical features of type 1 hyperlipoproteinemia were recruited for DNA sequencing of the LPL gene. Pre-heparin and post-heparin plasma of patients were used for protein detection analysis and functional test. Furthermore, in vitro experiments were performed in HEK293 cells. Protein synthesis and secretion were analyzed in lysate and medium fraction, respectively, whereas medium fraction was used for functional assay. RESULTS We identified two novel mutations in the LPL gene causing type 1 hyperlipoproteinemia: a two base pair deletion (c.765_766delAG) resulting in a frameshift at position 256 of the protein (p.G256TfsX26) and a nucleotide substitution (c.1211 T > G) resulting in a methionine to arginine substitution (p.M404 R). LPL protein and activity were not detected in pre-heparin or post-heparin plasma of the patient with p.G256TfsX26 mutation or in the medium of HEK293 cells over-expressing recombinant p.G256TfsX26 LPL. A relatively small amount of LPL p.M404 R was detected in both pre-heparin and post-heparin plasma and in the medium of the cells, whereas no LPL activity was detected. CONCLUSIONS We conclude that these two novel mutations cause type 1 hyperlipoproteinemia by inducing a loss or reduction in LPL secretion accompanied by a loss of LPL enzymatic activity.
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Affiliation(s)
- Piero Pingitore
- Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Saverio Massimo Lepore
- Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy
| | - Carlo Pirazzi
- Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden; Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden
| | | | - Benedetta Maria Motta
- Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Luca Valenti
- Internal Medicine, Fondazione IRCCS Ca' Granda Ospedale Policlinico Milano, Milan, Italy; Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milan, Italy
| | - Knut Erik Berge
- Unit for Cardiac and Cardiovascular Genetics, Department of Medical Genetics, Oslo University Hospital, Ullevaal, Oslo, Norway
| | - Kjetil Retterstøl
- Department of Nutrition, Institute for Basic Medical Sciences, University of Oslo, Oslo, Norway; Lipid Clinic, Oslo University Hospital, Rikshospitalet, Oslo, Norway
| | - Trond P Leren
- Unit for Cardiac and Cardiovascular Genetics, Department of Medical Genetics, Oslo University Hospital, Ullevaal, Oslo, Norway
| | - Olov Wiklund
- Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden; Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden; Clinical Nutrition Unit, Department of Medical and Surgical Sciences, Magna Graecia University, Catanzaro, Italy; Cardiology Department, Sahlgrenska University Hospital, Gothenburg, Sweden.
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21
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Donati B, Motta BM, Pingitore P, Meroni M, Pietrelli A, Alisi A, Petta S, Xing C, Dongiovanni P, del Menico B, Rametta R, Mancina RM, Badiali S, Fracanzani AL, Craxì A, Fargion S, Nobili V, Romeo S, Valenti L. The rs2294918 E434K variant modulates patatin-like phospholipase domain-containing 3 expression and liver damage. Hepatology 2016; 63:787-98. [PMID: 26605757 DOI: 10.1002/hep.28370] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 11/23/2015] [Indexed: 12/23/2022]
Abstract
UNLABELLED The patatin-like phosholipase domain-containing 3 (PNPLA3) rs738409 polymorphism (I148M) is a major determinant of hepatic fat and predisposes to the full spectrum of liver damage in nonalcoholic fatty liver disease (NAFLD). The aim of this study was to evaluate whether additional PNPLA3 coding variants contribute to NAFLD susceptibility, first in individuals with contrasting phenotypes (with early-onset NAFLD vs. very low aminotransferases) and then in a large validation cohort. Rare PNPLA3 variants were not detected by sequencing coding regions and intron-exon boundaries either in 142 patients with early-onset NAFLD nor in 100 healthy individuals with alanine aminotransferase <22/20 IU/mL. Besides rs738409 I148M, the rs2294918 G>A polymorphism (E434K sequence variant) was over-represented in NAFLD (adjusted P = 0.01). In 1,447 subjects with and without NAFLD, the 148M-434E (P < 0.0001), but not the 148M-434K, haplotype (P > 0.9), was associated with histological NAFLD and steatohepatitis. Both the I148M (P = 0.0002) and E434K variants (P = 0.044) were associated with serum ALT levels, by interacting with each other, in that the 434K hampered the association with liver damage of the 148M allele (P = 0.006). The E434K variant did not affect PNPLA3 enzymatic activity, but carriers of the rs2294918 A allele (434K) displayed lower hepatic PNPLA3 messenger RNA and protein levels (P < 0.05). CONCLUSIONS Rare loss-of-function PNPLA3 variants were not detected in early-onset NAFLD. However, PNPLA3 rs2294918 E434K decreased PNPLA3 expression, lessening the effect of the I148M variant on the predisposition to steatosis and liver damage. This suggests that the PNPLA3 I148M variant has a codominant negative effect on triglycerides mobilization from lipid droplets, mediated by inhibition of other lipases.
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Affiliation(s)
- Benedetta Donati
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Policlinico, Milano, Italy
| | - Benedetta Maria Motta
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Policlinico, Milano, Italy.,Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Piero Pingitore
- Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Marica Meroni
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Policlinico, Milano, Italy
| | - Alessandro Pietrelli
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Policlinico, Milano, Italy.,Istituto Nazionale Genetica Molecolare (INGM), "Romeo ed Enrica Invernizzi", Bioinformatic Group, Milano, Italy
| | - Anna Alisi
- Hepato-Metabolic Unit, Ospedale Bambin Gesù, Roma, Italy
| | - Salvatore Petta
- Department of Gastroenterology, Università di Palermo, Palermo, Italy
| | - Chao Xing
- UT Southwestern Medical Center, Dallas, TX
| | - Paola Dongiovanni
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Policlinico, Milano, Italy
| | - Benedetta del Menico
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Policlinico, Milano, Italy
| | - Raffaela Rametta
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Policlinico, Milano, Italy
| | - Rosellina Margherita Mancina
- Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Sara Badiali
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Policlinico, Milano, Italy
| | - Anna Ludovica Fracanzani
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Policlinico, Milano, Italy
| | - Antonio Craxì
- Department of Gastroenterology, Università di Palermo, Palermo, Italy
| | - Silvia Fargion
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Policlinico, Milano, Italy
| | - Valerio Nobili
- Hepato-Metabolic Unit, Ospedale Bambin Gesù, Roma, Italy
| | - Stefano Romeo
- Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, University of Gothenburg, Gothenburg, Sweden.,Clinical Nutrition Unit, Department of Medical and Surgical Sciences, University Magna Graecia, Catanzaro, Italy.,Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Luca Valenti
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Policlinico, Milano, Italy
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22
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Burza MA, Motta BM, Mancina RM, Pingitore P, Pirazzi C, Lepore SM, Spagnuolo R, Doldo P, Russo C, Lazzaro V, Fischer J, Berg T, Aghemo A, Cheroni C, De Francesco R, Fargion S, Colombo M, Datz C, Stickel F, Valenti L, Romeo S. DEPDC5 variants increase fibrosis progression in Europeans with chronic hepatitis C virus infection. Hepatology 2016; 63:418-27. [PMID: 26517016 PMCID: PMC4737289 DOI: 10.1002/hep.28322] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 10/25/2015] [Indexed: 12/11/2022]
Abstract
UNLABELLED Chronic hepatitis C virus (HCV) infection may progress to cirrhosis and hepatocellular carcinoma (HCC). Recently, two genetic variants, DEPDC5 rs1012068 and MICA rs2596542, were associated with the onset of HCC in Asian subjects with chronic HCV infection. The aim of the present study was to analyze whether DEPDC5 and MICA genetic variants were associated with liver disease progression in European subjects with chronic HCV infection. In a Northern Italian discovery cohort (n = 477), neither DEPDC5 rs1012068 nor MICA rs2596542 were associated with HCC (n = 150). However, DEPDC5 rs1012068 was independently associated with cirrhosis (n = 300; P = 0.049). The association of rs1012068 with moderate to severe fibrosis was confirmed in an independent cross-sectional German cohort (n = 415; P = 0.006). Furthermore, DEPDC5 rs1012068 predicted faster fibrosis progression in a prospective cohort (n = 247; P = 0.027). Next, we examined the distribution of nonsynonymous DEPDC5 variants in the overall cross-sectional cohort (n = 912). The presence of at least one variant increased the risk of moderate/severe fibrosis by 54% (P = 0.040). To understand the molecular mechanism underlying the genetic association of DEPDC5 variants with fibrosis progression, we performed in vitro studies on immortalized hepatic stellate cells (LX-2). In these cells, down-regulation of DEPDC5 resulted in increased expression of β-catenin and production of its target matrix metallopeptidase 2 (MMP2), a secreted enzyme involved in fibrosis progression. CONCLUSION DEPDC5 variants increase fibrosis progression in European subjects with chronic HCV infection. Our findings suggest that DEPDC5 down-regulation may contribute to HCV-related fibrosis by increasing MMP2 synthesis through the β-catenin pathway.
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Affiliation(s)
- Maria Antonella Burza
- Department of Molecular and Clinical Medicine, Sahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | - Benedetta Maria Motta
- Department of Molecular and Clinical Medicine, Sahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | | | - Piero Pingitore
- Department of Molecular and Clinical Medicine, Sahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | - Carlo Pirazzi
- Department of Molecular and Clinical Medicine, Sahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | - Saverio Massimo Lepore
- Clinical Nutrition Unit, Department of Medical and Surgical SciencesMagna Graecia UniversityCatanzaroItaly
| | - Rocco Spagnuolo
- Department of Experimental and Clinical MedicineMagna Graecia UniversityCatanzaroItaly
| | - Patrizia Doldo
- Department of Experimental and Clinical MedicineMagna Graecia UniversityCatanzaroItaly
| | - Cristina Russo
- Clinical Nutrition Unit, Department of Medical and Surgical SciencesMagna Graecia UniversityCatanzaroItaly
| | - Veronica Lazzaro
- Clinical Nutrition Unit, Department of Medical and Surgical SciencesMagna Graecia UniversityCatanzaroItaly
| | - Janett Fischer
- Department of Gastroenterology and Rheumatology, Section of HepatologyUniversity HospitalLeipzigGermany
| | - Thomas Berg
- Department of Gastroenterology and Rheumatology, Section of HepatologyUniversity HospitalLeipzigGermany
| | - Alessio Aghemo
- Department of GastroenterologyFondazione IRCCS Ca' Granda Ospedale Policlinico MilanoMilanItaly
| | - Cristina Cheroni
- Virology ProgramINGM‐Istituto Nazionale di Genetica Molecolare “Romeo ed Enrica Invernizzi”MilanItaly
| | - Raffaele De Francesco
- Virology ProgramINGM‐Istituto Nazionale di Genetica Molecolare “Romeo ed Enrica Invernizzi”MilanItaly
| | - Silvia Fargion
- Università degli Studi di Milano, Fondazione IRCCS Ca'Granda Ospedale Policlinico Milano, Department of Pathophysiology and TransplantationMilanItaly
| | - Massimo Colombo
- Department of GastroenterologyFondazione IRCCS Ca' Granda Ospedale Policlinico MilanoMilanItaly,Università degli Studi di Milano, Fondazione IRCCS Ca'Granda Ospedale Policlinico Milano, Department of Pathophysiology and TransplantationMilanItaly
| | - Christian Datz
- Department of Internal Medicine, Hospital OberndorfTeaching Hospital of the Paracelsus Private University of SalzburgOberndorfAustria
| | - Felix Stickel
- Department of Gastroenterology and HepatologyUniversity Hospital of Zürich, Rämistrasse 100, CH‐8091ZürichSwitzerland
| | - Luca Valenti
- Università degli Studi di Milano, Fondazione IRCCS Ca'Granda Ospedale Policlinico Milano, Department of Pathophysiology and TransplantationMilanItaly
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, Sahlgrenska AcademyUniversity of GothenburgGothenburgSweden,Clinical Nutrition Unit, Department of Medical and Surgical SciencesMagna Graecia UniversityCatanzaroItaly,Department of CardiologySahlgrenska University HospitalGothenburgSweden
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23
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Pirazzi C, Valenti L, Motta BM, Pingitore P, Hedfalk K, Mancina RM, Burza MA, Indiveri C, Ferro Y, Montalcini T, Maglio C, Dongiovanni P, Fargion S, Rametta R, Pujia A, Andersson L, Ghosal S, Levin M, Wiklund O, Iacovino M, Borén J, Romeo S. PNPLA3 has retinyl-palmitate lipase activity in human hepatic stellate cells. Hum Mol Genet 2014; 23:4077-85. [PMID: 24670599 PMCID: PMC4082369 DOI: 10.1093/hmg/ddu121] [Citation(s) in RCA: 252] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Retinoids are micronutrients that are stored as retinyl esters in the retina and hepatic stellate cells (HSCs). HSCs are key players in fibrogenesis in chronic liver diseases. The enzyme responsible for hydrolysis and release of retinyl esters from HSCs is unknown and the relationship between retinoid metabolism and liver disease remains unclear. We hypothesize that the patatin-like phospholipase domain-containing 3 (PNPLA3) protein is involved in retinol metabolism in HSCs. We tested our hypothesis both in primary human HSCs and in a human cohort of subjects with non-alcoholic fatty liver disease (N = 146). Here we show that PNPLA3 is highly expressed in human HSCs. Its expression is regulated by retinol availability and insulin, and increased PNPLA3 expression results in reduced lipid droplet content. PNPLA3 promotes extracellular release of retinol from HSCs in response to insulin. We also show that purified wild-type PNPLA3 hydrolyzes retinyl palmitate into retinol and palmitic acid. Conversely, this enzymatic activity is markedly reduced with purified PNPLA3 148M, a common mutation robustly associated with liver fibrosis and hepatocellular carcinoma development. We also find the PNPLA3 I148M genotype to be an independent (P = 0.009 in a multivariate analysis) determinant of circulating retinol-binding protein 4, a reliable proxy for retinol levels in humans. This study identifies PNPLA3 as a lipase responsible for retinyl-palmitate hydrolysis in HSCs in humans. Importantly, this indicates a potential novel link between HSCs, retinoid metabolism and PNPLA3 in determining the susceptibility to chronic liver disease.
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Affiliation(s)
- Carlo Pirazzi
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory and
| | - Luca Valenti
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Benedetta Maria Motta
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory and Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Piero Pingitore
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden Department BEST (Biologia, Ecologia, Scienze Della Terra), Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Arcavacata di Rende, Italy
| | - Kristina Hedfalk
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Rosellina Margherita Mancina
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory and Department of Medical and Surgical Sciences, Clinical Nutrition Unit, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Maria Antonella Burza
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory and
| | - Cesare Indiveri
- Department BEST (Biologia, Ecologia, Scienze Della Terra), Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Arcavacata di Rende, Italy
| | - Yvelise Ferro
- Department of Medical and Surgical Sciences, Clinical Nutrition Unit, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Tiziana Montalcini
- Department of Medical and Surgical Sciences, Clinical Nutrition Unit, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Cristina Maglio
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory and
| | - Paola Dongiovanni
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Silvia Fargion
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Raffaela Rametta
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Arturo Pujia
- Department of Medical and Surgical Sciences, Clinical Nutrition Unit, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Linda Andersson
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory and
| | - Saswati Ghosal
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory and
| | - Malin Levin
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory and
| | - Olov Wiklund
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory and
| | - Michelina Iacovino
- Department of Pediatrics, LA Biomedical Research Institute at Harbor-UCLA, 1124 W. Carson Street, HH1, Torrance, CA 90502, USA
| | - Jan Borén
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory and
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory and Department of Medical and Surgical Sciences, Clinical Nutrition Unit, University Magna Graecia of Catanzaro, Catanzaro, Italy
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24
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Galluccio M, Pingitore P, Scalise M, Indiveri C. Cloning, large scale over-expression in E. coli and purification of the components of the human LAT 1 (SLC7A5) amino acid transporter. Protein J 2014; 32:442-8. [PMID: 23912240 DOI: 10.1007/s10930-013-9503-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The high yield expression of the human LAT1 transporter has been obtained for the first time using E. coli. The hLAT1 cDNA was amplified from HEK293 cells and cloned in pH6EX3 vector. The construct pH6EX3-6His-hLAT1 was used to express the 6His-hLAT1 protein in the Rosetta(DE3)pLysS strain of E. coli. The highest level of expression was detected 8 h after induction by IPTG at 28 °C. The expressed protein was collected in the insoluble fraction of cell lysate. On SDS-PAGE the apparent molecular mass of the polypeptide was 40 kDa. After solubilization with sarkosyl and denaturation with urea the protein carrying a 6His N-terminal tag was purified by Ni(2+)-chelating affinity chromatography and identified by anti-His antibody. The yield of the over-expressed protein after purification was 3.5 mg/L (cell culture). The human CD98 cDNA amplified from Imagene plasmid was cloned in pGEX-4T1. The construct pGEX-4T1-hCD98 was used to express the GST-hCD98 protein in the Rosetta(DE3)pLysS strain of E. coli. The highest level of expression was detected in this case 4 h after induction by IPTG at 28 °C. The expressed protein was accumulated in the soluble fraction of cell lysate. The molecular mass was determined on the basis of marker proteins on SDS-PAGE; it was about 110 kDa. GST was cleaved from the protein construct by incubation with thrombin for 12 h and the hCD98 was separated by Sephadex G-200 chromatography (size exclusion). hCD98 showed a 62 kDa apparent molecular mass, as determined on the basis of molecular mass markers using SDS-PAGE. The yield of CD98 was 2 mg/L of cell culture.
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Affiliation(s)
- Michele Galluccio
- Unit of Biochemistry and Molecular Biotechnology, Department BEST (Biologia, Ecologia, Scienze della Terra), University of Calabria, Via P. Bucci 4c, 87036, Arcavacata di Rende, Italy
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25
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Pingitore P, Pirazzi C, Mancina RM, Motta BM, Indiveri C, Pujia A, Montalcini T, Hedfalk K, Romeo S. Recombinant PNPLA3 protein shows triglyceride hydrolase activity and its I148M mutation results in loss of function. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1841:574-80. [PMID: 24369119 DOI: 10.1016/j.bbalip.2013.12.006] [Citation(s) in RCA: 130] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 12/07/2013] [Accepted: 12/14/2013] [Indexed: 12/13/2022]
Abstract
The patatin-like phospholipase domain containing 3 (PNPLA3, also called adiponutrin, ADPN) is a membrane-bound protein highly expressed in the liver. The genetic variant I148M (rs738409) was found to be associated with progression of chronic liver disease. We aimed to establish a protein purification protocol in a yeast system (Pichia pastoris) and to examine the human PNPLA3 enzymatic activity, substrate specificity and the I148M mutation effect. hPNPLA3 148I wild type and 148M mutant cDNA were cloned into P. pastoris expression vectors. Yeast cells were grown in 3L fermentors. PNPLA3 protein was purified from membrane fractions by Ni-affinity chromatography. Enzymatic activity was assessed using radiolabeled substrates. Both 148I wild type and 148M mutant proteins are localized to the membrane. The wild type protein shows a predominant lipase activity with mild lysophosphatidic acid acyl transferase activity (LPAAT) and the I148M mutation results in a loss of function of both these activities. Our data show that PNPLA3 has a predominant lipase activity and I148M mutation results in a loss of function.
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Affiliation(s)
- Piero Pingitore
- Department BEST (Biologia, Ecologia, Scienze della Terra), Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci 4c, 87036 Arcavacata di Rende, Italy; Department of Chemistry and Molecular Biology, University of Gothenburg, PO Box 462, SE-405 30 Göteborg, Sweden
| | - Carlo Pirazzi
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, University of Gothenburg, Bruna Stråket, 16 SE-413 45 Göteborg, Sweden
| | - Rosellina M Mancina
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, University of Gothenburg, Bruna Stråket, 16 SE-413 45 Göteborg, Sweden; Department of Medical and Surgical Sciences, Clinical Nutrition Unit, University Magna Graecia of Catanzaro, Viale Europa, Localitá Germaneto, 88100 Catanzaro, Italy
| | - Benedetta M Motta
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, University of Gothenburg, Bruna Stråket, 16 SE-413 45 Göteborg, Sweden; Department of Pathophysiology and Transplantation, University of Milan, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122 Milan, Italy
| | - Cesare Indiveri
- Department BEST (Biologia, Ecologia, Scienze della Terra), Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci 4c, 87036 Arcavacata di Rende, Italy
| | - Arturo Pujia
- Department of Medical and Surgical Sciences, Clinical Nutrition Unit, University Magna Graecia of Catanzaro, Viale Europa, Localitá Germaneto, 88100 Catanzaro, Italy
| | - Tiziana Montalcini
- Department of Medical and Surgical Sciences, Clinical Nutrition Unit, University Magna Graecia of Catanzaro, Viale Europa, Localitá Germaneto, 88100 Catanzaro, Italy
| | - Kristina Hedfalk
- Department of Chemistry and Molecular Biology, University of Gothenburg, PO Box 462, SE-405 30 Göteborg, Sweden.
| | - Stefano Romeo
- Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, University of Gothenburg, Bruna Stråket, 16 SE-413 45 Göteborg, Sweden; Department of Medical and Surgical Sciences, Clinical Nutrition Unit, University Magna Graecia of Catanzaro, Viale Europa, Localitá Germaneto, 88100 Catanzaro, Italy.
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26
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Pingitore P, Pochini L, Scalise M, Galluccio M, Hedfalk K, Indiveri C. Large scale production of the active human ASCT2 (SLC1A5) transporter in Pichia pastoris--functional and kinetic asymmetry revealed in proteoliposomes. Biochim Biophys Acta 2013; 1828:2238-46. [PMID: 23756778 DOI: 10.1016/j.bbamem.2013.05.034] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2013] [Revised: 05/28/2013] [Accepted: 05/31/2013] [Indexed: 12/11/2022]
Abstract
The human glutamine/neutral amino acid transporter ASCT2 (hASCT2) was over-expressed in Pichia pastoris and purified by Ni(2+)-chelating and gel filtration chromatography. The purified protein was reconstituted in liposomes by detergent removal with a batch-wise procedure. Time dependent [(3)H]glutamine/glutamine antiport was measured in proteoliposomes which was active only in the presence of external Na(+). Internal Na(+) slightly stimulated the antiport. Optimal activity was found at pH7.0. A substantial inhibition of the transport was observed by Cys, Thr, Ser, Ala, Asn and Met (≥70%) and by mercurials and methanethiosulfonates (≥80%). Heterologous antiport of [(3)H]glutamine with other neutral amino acids was also studied. The transporter showed asymmetric specificity for amino acids: Ala, Cys, Val, Met were only inwardly transported, while Gln, Ser, Asn, and Thr were transported bi-directionally. From kinetic analysis of [(3)H]glutamine/glutamine antiport Km values of 0.097 and 1.8mM were measured on the external and internal sides of proteoliposomes, respectively. The Km for Na(+) on the external side was 32mM. The homology structural model of the hASCT2 protein was built using the GltPh of Pyrococcus horikoshii as template. Cys395 was the only Cys residue externally exposed, thus being the potential target of SH reagents inhibition and, hence, potentially involved in the transport mechanism.
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Affiliation(s)
- Piero Pingitore
- Department BEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci 4c, 87036 Arcavacata di Rende, Italy.
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27
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Palmieri G, de Franciscis V, Casamassimi A, Romano G, Torino A, Pingitore P, Califano D, Santelli G, Eva A, Vecchio G, D'Urso M, Ciccodicola A. Human dbl proto-oncogene in 85 kb of xq26, and determination of the transcription initiation site. Gene 2000; 253:107-15. [PMID: 10925207 DOI: 10.1016/s0378-1119(00)00212-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The dbl oncogene is generated by substitution of the 5' portion of its normal counterpart with an unrelated human sequence. To analyze the genomic structure and transcriptional regulation of the dbl proto-oncogene, we have isolated human genomic clones containing the entire human proto-dbl gene, localized in Xq26. Restriction mapping of a 600kb YAC clone (yWXD311) placed proto-dbl about 50kb telomeric to the coagulation Factor IX gene. The genomic DNA fragment containing the 5' end of proto-dbl was subcloned into plasmid vectors and the nucleotide sequences of exon 1, the flanking intronic region and genomic DNA 5' of the first codon were determined. Sequence analysis of 85119bp from the region revealed the genomic structure of proto-dbl. It contains 25 exons coding for a 4.7kb transcript including large 5'- and 3'- (1218bp and 701bp, respectively) untranslated regions (UTRs). RNase protection and primer extension assays on RNA from medullary thyroid carcinoma (TT) cells, which normally express dbl, revealed a transcription start site 1218bp upstream of the ATG of the first exon. A 1.6kb genomic 5' of the translation start sites drives the expression of a CAT-reporter in transient transfections in the TT cell line, though lacking TATA or CAAT boxes.
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Affiliation(s)
- G Palmieri
- International Institute of Genetics and Biophysics, C.N.R., Via Marconi 10, Naples, Italy
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