{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,16]],"date-time":"2026-05-16T15:51:11Z","timestamp":1778946671497,"version":"3.51.4"},"reference-count":32,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2021,9,9]],"date-time":"2021-09-09T00:00:00Z","timestamp":1631145600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000062","name":"National Institute of Diabetes and Digestive and Kidney Diseases","doi-asserted-by":"publisher","award":["R01 DK106621 (EKS); R01 DK107904 (EKS)"],"award-info":[{"award-number":["R01 DK106621 (EKS); R01 DK107904 (EKS)"]}],"id":[{"id":"10.13039\/100000062","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100007270","name":"University of Michigan","doi-asserted-by":"publisher","award":["Department of Internal Medicine"],"award-info":[{"award-number":["Department of Internal Medicine"]}],"id":[{"id":"10.13039\/100007270","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Non-alcoholic fatty liver disease (NAFLD) is caused by excess lipid accumulation in hepatocytes. Genome-wide association studies have identified a strong association of NAFLD with non-synonymous E167K amino acid mutation in the transmembrane 6 superfamily member 2 (TM6SF2) protein. The E167K mutation reduces TM6SF2 stability, and its carriers display increased hepatic lipids and lower serum triglycerides. However, the effects of TM6SF2 on hepatic lipid metabolism are not completely understood. We overexpressed wild-type or E167K variant of TM6SF2 or knocked down TM6SF2 expression in lipid-treated Huh-7 cells and used untargeted lipidomic analysis, RNAseq transcriptome analysis, and fluorescent imaging to determine changes in hepatic lipid metabolism. Both TM6SF2 knockdown and E167K overexpression increased hepatic lipid accumulation, while wild-type overexpression decreased acylglyceride levels. We also observed lipid chain remodeling for acylglycerides by TM6SF2 knockdown, leading to a relative increase in species with shorter, more saturated side chains. RNA-sequencing revealed differential expression of several lipid metabolizing genes, including genes belonging to AKR1 family and lipases, primarily in cells with TM6SF2 knockdown. Taken together, our data show that overexpression of TM6SF2 gene or its loss-of-function changes hepatic lipid species composition and expression of lipid metabolizing genes. Additionally, our data further confirms a loss-of-function effect for the E167K variant.<\/jats:p>","DOI":"10.3390\/ijms22189758","type":"journal-article","created":{"date-parts":[[2021,9,9]],"date-time":"2021-09-09T12:20:37Z","timestamp":1631190037000},"page":"9758","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Perturbation of TM6SF2 Expression Alters Lipid Metabolism in a Human Liver Cell Line"],"prefix":"10.3390","volume":"22","author":[{"given":"Asmita","family":"Pant","sequence":"first","affiliation":[{"name":"Division of Gastroenterology and Hepatology, University of Michigan Health System, Ann Arbor, MI 48109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yue","family":"Chen","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology and Hepatology, University of Michigan Health System, Ann Arbor, MI 48109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Annapurna","family":"Kuppa","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology and Hepatology, University of Michigan Health System, Ann Arbor, MI 48109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaomeng","family":"Du","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology and Hepatology, University of Michigan Health System, Ann Arbor, MI 48109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Brian D.","family":"Halligan","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology and Hepatology, University of Michigan Health System, Ann Arbor, MI 48109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elizabeth K.","family":"Speliotes","sequence":"additional","affiliation":[{"name":"Division of Gastroenterology and Hepatology, University of Michigan Health System, Ann Arbor, MI 48109, USA"},{"name":"Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI 48109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1851","DOI":"10.1053\/j.gastro.2020.01.052","article-title":"Nonalcoholic Fatty Liver Disease 2020: The State of the Disease","volume":"158","author":"Cotter","year":"2020","journal-title":"Gastroenterology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1111\/liv.13301","article-title":"Pathology of non-alcoholic fatty liver disease","volume":"37","author":"Bedossa","year":"2017","journal-title":"Liver Int."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1196","DOI":"10.1016\/j.jhep.2020.02.020","article-title":"Update on NAFLD genetics: From new variants to the clinic","volume":"72","author":"Valenti","year":"2020","journal-title":"J. Hepatol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"352","DOI":"10.1038\/ng.2901","article-title":"Exome-wide association study identifies a TM6SF2 variant that confers susceptibility to nonalcoholic fatty liver disease","volume":"46","author":"Kozlitina","year":"2014","journal-title":"Nat. Genet."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1959","DOI":"10.1111\/liv.12781","article-title":"TM6SF2 E167K variant is associated with severe steatosis in chronic hepatitis C, regardless of PNPLA3 polymorphism","volume":"35","author":"Coppola","year":"2015","journal-title":"Liver Int."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"657","DOI":"10.1016\/j.jhep.2014.10.010","article-title":"Circulating triacylglycerol signatures and insulin sensitivity in NAFLD associated with the E167K variant in TM6SF2","volume":"62","author":"Zhou","year":"2015","journal-title":"J. Hepatol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"4309","DOI":"10.1038\/ncomms5309","article-title":"TM6SF2 rs58542926 influences hepatic fibrosis progression in patients with non-alcoholic fatty liver disease","volume":"5","author":"Liu","year":"2014","journal-title":"Nat. Commun."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"506","DOI":"10.1002\/hep.27490","article-title":"Transmembrane 6 superfamily member 2 gene variant disentangles nonalcoholic steatohepatitis from cardiovascular disease","volume":"61","author":"Dongiovanni","year":"2015","journal-title":"Hepatology"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"515","DOI":"10.1002\/hep.27556","article-title":"Genetic variation in transmembrane 6 superfamily member 2 and the risk of nonalcoholic fatty liver disease and histological disease severity","volume":"61","author":"Sookoian","year":"2015","journal-title":"Hepatology"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"8913","DOI":"10.1073\/pnas.1323785111","article-title":"TM6SF2 is a regulator of liver fat metabolism influencing triglyceride secretion and hepatic lipid droplet content","volume":"111","author":"Mahdessian","year":"2014","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"345","DOI":"10.1038\/ng.2926","article-title":"Systematic evaluation of coding variation identifies a candidate causal variant in TM6SF2 influencing total cholesterol and myocardial infarction risk","volume":"46","author":"Holmen","year":"2014","journal-title":"Nat. Genet."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1742","DOI":"10.1002\/hep.28142","article-title":"The dual and opposite role of the TM6SF2-rs58542926 variant in protecting against cardiovascular disease and conferring risk for nonalcoholic fatty liver: A meta-analysis","volume":"62","author":"Pirola","year":"2015","journal-title":"Hepatology"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"10659","DOI":"10.1074\/jbc.M116.719955","article-title":"Inactivation of Tm6sf2, a Gene Defective in Fatty Liver Disease, Impairs Lipidation but Not Secretion of Very Low Density Lipoproteins","volume":"291","author":"Smagris","year":"2016","journal-title":"J. Biol. Chem."},{"key":"ref_14","first-page":"6","article-title":"Liver specific deletion of mouse Tm6sf2 promotes steatosis, fibrosis and hepatocellular cancer","volume":"4","author":"Newberry","year":"2021","journal-title":"Hepatology"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"e144079","DOI":"10.1172\/jci.insight.144079","article-title":"Effects of TM6SF2 E167K on hepatic lipid and very low-density lipoprotein metabolism in humans","volume":"5","author":"Adiels","year":"2020","journal-title":"JCI Insight"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"445","DOI":"10.1586\/egh.09.32","article-title":"Lipotoxicity in nonalcoholic fatty liver disease: Not all lipids are created equal","volume":"3","author":"Alkhouri","year":"2009","journal-title":"Expert Rev. Gastroenterol. Hepatol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"G75","DOI":"10.1152\/ajpgi.00170.2018","article-title":"Lipid mediators of liver injury in nonalcoholic fatty liver disease","volume":"316","author":"Liangpunsakul","year":"2019","journal-title":"Am. J. Physiol. Gastrointest. Liver Physiol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"2719","DOI":"10.1093\/hmg\/ddx159","article-title":"Hepatic Tm6sf2 overexpression affects cellular ApoB-trafficking, plasma lipid levels, hepatic steatosis and atherosclerosis","volume":"26","author":"Ehrhardt","year":"2017","journal-title":"Hum. Mol. Genet."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1208","DOI":"10.1053\/j.gastro.2016.01.005","article-title":"Hepatic Transmembrane 6 Superfamily Member 2 Regulates Cholesterol Metabolism in Mice","volume":"150","author":"Fan","year":"2016","journal-title":"Gastroenterology"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Li, B.-T., Sun, M., Li, Y.-F., Wang, J.-Q., Zhou, Z.-M., Song, B.-L., and Luo, J. (2020). Disruption of the ERLIN\u2013TM6SF2\u2013APOB complex destabilizes APOB and contributes to non-alcoholic fatty liver disease. PLoS Genet., 16.","DOI":"10.1371\/journal.pgen.1008955"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"11585","DOI":"10.1038\/s41598-019-47737-w","article-title":"The TM6SF2 E167K genetic variant induces lipid biosynthesis and reduces apolipoprotein B secretion in human hepatic 3D spheroids","volume":"9","author":"Prill","year":"2019","journal-title":"Sci. Rep."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"152","DOI":"10.1186\/s12967-021-02820-7","article-title":"Metabolic analysis of early nonalcoholic fatty liver disease in humans using liquid chromatography-mass spectrometry","volume":"19","author":"Hu","year":"2021","journal-title":"J. Transl. Med."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1081","DOI":"10.1002\/hep.21763","article-title":"A lipidomic analysis of nonalcoholic fatty liver disease","volume":"46","author":"Puri","year":"2007","journal-title":"Hepatology"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"436","DOI":"10.4254\/wjh.v12.i8.436","article-title":"Lipidomics in non-alcoholic fatty liver disease","volume":"12","author":"Kartsoli","year":"2020","journal-title":"World J. Hepatol."},{"key":"ref_25","unstructured":"Mann, J.P., Furse, S., Snowden, S.G., Alisi, A., Draijer, L.G., Jenkins, B., Karnebeek, K., Kelly, D.A., Koot, B.G., and Mosca, A. (2020). Plasma lipidomics distinguishes NASH and fibrosis from simple fatty liver in children. medRxiv."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"128","DOI":"10.1016\/j.jhep.2017.02.014","article-title":"Impaired hepatic lipid synthesis from polyunsaturated fatty acids in TM6SF2 E167K variant carriers with NAFLD","volume":"67","author":"Luukkonen","year":"2017","journal-title":"J. Hepatol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"676","DOI":"10.1016\/j.bbalip.2017.04.004","article-title":"Depletion of TM6SF2 disturbs membrane lipid composition and dynamics in HuH7 hepatoma cells","volume":"1862","author":"Ruhanen","year":"2017","journal-title":"Biochim. Biophys. Acta Mol. Cell Biol. Lipids"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1016\/j.steroids.2013.10.012","article-title":"Role of aldo-keto reductase family 1 (AKR1) enzymes in human steroid metabolism","volume":"79","author":"Penning","year":"2014","journal-title":"Steroids"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"220","DOI":"10.1016\/j.freeradbiomed.2020.12.011","article-title":"ER stress-induced adipocytes secrete-aldo-keto reductase 1B7-containing exosomes that cause nonalcoholic steatohepatitis in mice","volume":"163","author":"Gu","year":"2021","journal-title":"Free Radic. Biol. Med."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"549","DOI":"10.1007\/s00535-019-01551-3","article-title":"Serum aldo-keto reductase family 1 member B10 predicts advanced liver fibrosis and fatal complications of nonalcoholic steatohepatitis","volume":"54","author":"Kanno","year":"2019","journal-title":"J. Gastroenterol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"2119","DOI":"10.2337\/db19-2119-P","article-title":"2119-P: AKR1B10 Is Upregulated in Nonalcoholic Fatty Liver Disease and Is Regulated by Fatty Acid Loading in Hepatocytes and Hepatic Stellate Cells","volume":"68","author":"Davis","year":"2019","journal-title":"Diabetes"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1412","DOI":"10.1053\/j.gastro.2011.06.048","article-title":"Hepatitis B virus core promoter mutations contribute to hepatocarcinogenesis by deregulating SKP2 and its target, p21","volume":"141","author":"Huang","year":"2011","journal-title":"Gastroenterology"}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/22\/18\/9758\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:59:49Z","timestamp":1760165989000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/22\/18\/9758"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,9,9]]},"references-count":32,"journal-issue":{"issue":"18","published-online":{"date-parts":[[2021,9]]}},"alternative-id":["ijms22189758"],"URL":"https:\/\/doi.org\/10.3390\/ijms22189758","relation":{"has-preprint":[{"id-type":"doi","id":"10.1101\/2021.08.04.455062","asserted-by":"object"}]},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,9,9]]}}}