Sebastian Cremer1,2, Katharina M Michalik1, Ariane Fischer1, Larissa Pfisterer1, Nicolas Jaé1, Carla Winter3, Reinier A Boon1,4,5, Marion Muhly-Reinholz1, David John1, Shizuka Uchida1,6, Christian Weber3,5,7, Wolfgang Poller8, Stefan Günther9, Thomas Braun9, Daniel Y Li10, Lars Maegdefessel3,10, Ljubica Perisic Matic11, Ulf Hedin11, Oliver Soehnlein3,5,12, Andreas Zeiher2,5, Stefanie Dimmeler1,5. 1. Institute for Cardiovascular Regeneration, Centre of Molecular Medicine, Goethe University, Frankfurt, Germany (S.C., K.M.M., A.F., L.P., N.J., R.A.B., M.M.-R., D.J., S.U., S.D.). 2. Department of Cardiology, Internal Medicine III, Johann Wolfgang Goethe-University Hospital, Frankfurt, Germany (S.C., A.Z.). 3. Institute for Cardiovascular Prevention (IPEK), Ludwig Maximilians University, Munich, Germany (C. Winter, C. Weber, L.M., O.S.). 4. Department of Physiology, Amsterdam Cardiovascular Sciences, VU University Medical Center, Amsterdam, the Netherlands (R.A.B.). 5. German Centre of Cardiovascular Research (DZHK), Berlin-Wedding, Germany (R.A.B., C. Weber, O.S., A.Z., S.D.). 6. Cardiovascular Innovation Institute University of Louisville, KY (S.U.). 7. Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht, The Netherlands (C. Weber). 8. Charité Centrum für Herz-, Kreislauf- und Gefäßmedizin, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Germany (W.P.). 9. Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany (S.G., T.B.). 10. Department of Vascular and Endovascular Surgery, Klinikum rechts der Isar der Technischen Universität München, Germany (D.Y.L., L.M.). 11. Department of Molecular Medicine and Surgery, Karolinska University Hospital, Stockholm, Sweden (L.P.M., U.H.). 12. Department of Physiology and Pharmacology (FyFa), Karolinska Institutet, Stockholm, Sweden (O.S.).
Abstract
BACKGROUND: The majority of the human genome comprises noncoding sequences, which are in part transcribed as long noncoding RNAs (lncRNAs). lncRNAs exhibit multiple functions, including the epigenetic control of gene expression. In this study, the effect of the lncRNA MALAT1 (metastasis-associated lung adenocarcinoma transcript 1) on atherosclerosis was examined. METHODS: The effect of MALAT1 on atherosclerosis was determined in apolipoprotein E-deficient (Apoe-/-) MALAT1-deficient (Malat1-/-) mice that were fed with a high-fat diet and by studying the regulation of MALAT1 in human plaques. RESULTS: Apoe-/- Malat1-/- mice that were fed a high-fat diet showed increased plaque size and infiltration of inflammatory CD45+ cells compared with Apoe-/- Malat1+/+ control mice. Bone marrow transplantation of Apoe-/- Malat1-/- bone marrow cells in Apoe-/- Malat1+/+ mice enhanced atherosclerotic lesion formation, which suggests that hematopoietic cells mediate the proatherosclerotic phenotype. Indeed, bone marrow cells isolated from Malat1-/- mice showed increased adhesion to endothelial cells and elevated levels of proinflammatory mediators. Moreover, myeloid cells of Malat1-/- mice displayed enhanced adhesion to atherosclerotic arteries in vivo. The anti-inflammatory effects of MALAT1 were attributed in part to reduction of the microRNA miR-503. MALAT1 expression was further significantly decreased in human plaques compared with normal arteries and was lower in symptomatic versus asymptomatic patients. Lower levels of MALAT1 in human plaques were associated with a worse prognosis. CONCLUSIONS: Reduced levels of MALAT1 augment atherosclerotic lesion formation in mice and are associated with human atherosclerotic disease. The proatherosclerotic effects observed in Malat1-/- mice were mainly caused by enhanced accumulation of hematopoietic cells.
BACKGROUND: The majority of the human genome comprises noncoding sequences, which are in part transcribed as long noncoding RNAs (lncRNAs). lncRNAs exhibit multiple functions, including the epigenetic control of gene expression. In this study, the effect of the lncRNA MALAT1 (metastasis-associated lung adenocarcinoma transcript 1) on atherosclerosis was examined. METHODS: The effect of MALAT1 on atherosclerosis was determined in apolipoprotein E-deficient (Apoe-/-) MALAT1-deficient (Malat1-/-) mice that were fed with a high-fat diet and by studying the regulation of MALAT1 in human plaques. RESULTS:Apoe-/- Malat1-/- mice that were fed a high-fat diet showed increased plaque size and infiltration of inflammatory CD45+ cells compared with Apoe-/- Malat1+/+ control mice. Bone marrow transplantation of Apoe-/- Malat1-/- bone marrow cells in Apoe-/- Malat1+/+ mice enhanced atherosclerotic lesion formation, which suggests that hematopoietic cells mediate the proatherosclerotic phenotype. Indeed, bone marrow cells isolated from Malat1-/- mice showed increased adhesion to endothelial cells and elevated levels of proinflammatory mediators. Moreover, myeloid cells of Malat1-/- mice displayed enhanced adhesion to atherosclerotic arteries in vivo. The anti-inflammatory effects of MALAT1 were attributed in part to reduction of the microRNA miR-503. MALAT1 expression was further significantly decreased in human plaques compared with normal arteries and was lower in symptomatic versus asymptomatic patients. Lower levels of MALAT1 in human plaques were associated with a worse prognosis. CONCLUSIONS: Reduced levels of MALAT1 augment atherosclerotic lesion formation in mice and are associated with humanatherosclerotic disease. The proatherosclerotic effects observed in Malat1-/- mice were mainly caused by enhanced accumulation of hematopoietic cells.
Authors: Laura Denby; Judith C Sluimer; Francesca Vacante; Julie Rodor; Mukesh K Lalwani; Amira D Mahmoud; Matthew Bennett; Azzurra L De Pace; Eileen Miller; Kim Van Kuijk; Jenny de Bruijn; Marion Gijbels; Thomas C Williams; Michael B Clark; Jessica P Scanlon; Amanda C Doran; Rusty Montgomery; David E Newby; Mauro Giacca; Dónal O'Carroll; Patrick W F Hadoke; Andrew H Baker Journal: Circ Res Date: 2021-02-24 Impact factor: 17.367