<i>Mir147</i> Limits the Contribution of Non-Foamy Macrophages to Atherosclerosis
Abstract
BACKGROUND: Hypercholesterolemia and a high-fat diet promote 2 macrophage subtypes involved in atherosclerosis by inducing lipid droplet accumulation in foamy macrophages (FMs) and triggering inflammatory activation in non-foamy macrophages (NFMs). MicroRNAs are key regulators of macrophage subtypes in atherosclerosis; for instance, miR-10a-5p limits lipid droplet formation, while miR-155-5p enhances inflammation. miR-147-3p is upregulated by inflammatory stimuli in macrophages and in atherosclerotic lesions, suggesting a potential role in NFMs. METHODS: The role of miR-147-3p in macrophages, with or without enhanced green fluorescent protein expression, in atherosclerosis was examined in Apoe –/– (apolipoprotein E-deficient) mice with a myeloid cell-specific knockout of the microRNA 147 ( Mir147 ) gene. Using live-plaque 4D confocal imaging, we assessed lipid droplets, caspase-3 activation, phagocytosis of apoptotic DNA, cholesterol crystal (CC) formation, mitochondrial function, macrophage migration, and tubular membrane extension formation. Green fluorescent protein-tAgo2 (tagged Argonaute 2) immunoprecipitation combined with prime RNA sequencing was performed using atherosclerotic aortas from Apoe –/– mice that expressed tAgo2 in myeloid cells. The effect of the galectin-3 inhibitor GB1107 was studied using 4D live-plaque imaging. RESULTS: Unlike FMs, NFMs are primarily located in the plaque core and show higher miR-147-3p levels in both mouse and human atherosclerosis. Knocking out Mir147 in myeloid cells increases atherosclerosis, with enhanced CC formation and apoptotic DNA accumulation in necrotic cores. Removing Mir147 reduces mitochondrial activity and elevates caspase-3 activity in NFMs, but not in FMs, and lowers the spare respiratory capacity of plaque macrophages. Moreover, deleting Mir147 impairs NFM uptake of apoptotic DNA, increases extracellular apoptotic DNA, and promotes CC formation. Additionally, Mir147 deficiency in NFMs induces caspase-3 activation in endothelial cells, facilitating the transendothelial extension of FM projections. The Lgals3 transcript, encoding galectin-3, was reduced in the tAgo2 immunoprecipitate after Mir147 knockout. A miR-147-3p binding site in the Lgals3 3’-UTR was functionally confirmed. GB1107 treatment reversed the Mir147 knockout effect in macrophages. CONCLUSIONS: miR-147-3p reduces atherosclerosis by suppressing the harmful effects of NFMs on endothelial cells and by enhancing their clearance of apoptotic DNA through targeting galectin-3. Increasing miR-147-3p levels might thus slow the expansion of the necrotic core and reduce atherothrombosis caused by NFM-induced endothelial damage.
Article Details
Authors (25)
Nan Li
Khadijeh Taherdangkoo
Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich; Munich, Germany (N.L., K.T., I.M.B., T.G., Q.M., S.L., Y.Z., X.L., M.Z., S.K.P., C.G., R.T.A.M., H.N., Y.L., C.J., A.B., Y.D., P.vH., C.W., M.N.-J., A.S.).
Isabelle M. Baatsch
Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich; Munich, Germany (N.L., K.T., I.M.B., T.G., Q.M., S.L., Y.Z., X.L., M.Z., S.K.P., C.G., R.T.A.M., H.N., Y.L., C.J., A.B., Y.D., P.vH., C.W., M.N.-J., A.S.).
Tanya Guduru
Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich; Munich, Germany (N.L., K.T., I.M.B., T.G., Q.M., S.L., Y.Z., X.L., M.Z., S.K.P., C.G., R.T.A.M., H.N., Y.L., C.J., A.B., Y.D., P.vH., C.W., M.N.-J., A.S.).
Qiuxing Meng
Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich; Munich, Germany (N.L., K.T., I.M.B., T.G., Q.M., S.L., Y.Z., X.L., M.Z., S.K.P., C.G., R.T.A.M., H.N., Y.L., C.J., A.B., Y.D., P.vH., C.W., M.N.-J., A.S.).
Shilun Li
Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich; Munich, Germany (N.L., K.T., I.M.B., T.G., Q.M., S.L., Y.Z., X.L., M.Z., S.K.P., C.G., R.T.A.M., H.N., Y.L., C.J., A.B., Y.D., P.vH., C.W., M.N.-J., A.S.).
Yanyi Zhou
Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich; Munich, Germany (N.L., K.T., I.M.B., T.G., Q.M., S.L., Y.Z., X.L., M.Z., S.K.P., C.G., R.T.A.M., H.N., Y.L., C.J., A.B., Y.D., P.vH., C.W., M.N.-J., A.S.).
Xinwei Li
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016, P. R. China
Mengyu Zhu
Sarah K. Polczer
Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich; Munich, Germany (N.L., K.T., I.M.B., T.G., Q.M., S.L., Y.Z., X.L., M.Z., S.K.P., C.G., R.T.A.M., H.N., Y.L., C.J., A.B., Y.D., P.vH., C.W., M.N.-J., A.S.).
Claudia Geissler
Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich; Munich, Germany (N.L., K.T., I.M.B., T.G., Q.M., S.L., Y.Z., X.L., M.Z., S.K.P., C.G., R.T.A.M., H.N., Y.L., C.J., A.B., Y.D., P.vH., C.W., M.N.-J., A.S.).
Eva Briem
Anthropology and Human Genomics, Faculty of Biology, Ludwig-Maximilians-University Munich; Martinsried, Germany (E.B., D.R., W.E.).
Remco T.A. Megens
Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich; Munich, Germany (N.L., K.T., I.M.B., T.G., Q.M., S.L., Y.Z., X.L., M.Z., S.K.P., C.G., R.T.A.M., H.N., Y.L., C.J., A.B., Y.D., P.vH., C.W., M.N.-J., A.S.).
Heya Na
State Key Laboratory of Virology and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences
Joerg Kumbrink
Institute for Pathology, Ludwig-Maximilians-University Munich; Munich, Germany (J.K.).
Daniel Richter
Ya Li
Carolin Jethwa
Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich; Munich, Germany (N.L., K.T., I.M.B., T.G., Q.M., S.L., Y.Z., X.L., M.Z., S.K.P., C.G., R.T.A.M., H.N., Y.L., C.J., A.B., Y.D., P.vH., C.W., M.N.-J., A.S.).
Alexander Bartelt
Yvonne Döring
Philipp von Hundelshausen
Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich; Munich, Germany (N.L., K.T., I.M.B., T.G., Q.M., S.L., Y.Z., X.L., M.Z., S.K.P., C.G., R.T.A.M., H.N., Y.L., C.J., A.B., Y.D., P.vH., C.W., M.N.-J., A.S.).
Wolfgang Enard
Christian Weber
Maliheh Nazari-Jahantigh
Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich; Munich, Germany (N.L., K.T., I.M.B., T.G., Q.M., S.L., Y.Z., X.L., M.Z., S.K.P., C.G., R.T.A.M., H.N., Y.L., C.J., A.B., Y.D., P.vH., C.W., M.N.-J., A.S.).
Andreas Schober
Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich; Munich, Germany (N.L., K.T., I.M.B., T.G., Q.M., S.L., Y.Z., X.L., M.Z., S.K.P., C.G., R.T.A.M., H.N., Y.L., C.J., A.B., Y.D., P.vH., C.W., M.N.-J., A.S.).