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Meiler S, Baumer Y, Toulmin E, Seng K, Boisvert WA. MicroRNA 302a is a novel modulator of cholesterol homeostasis and atherosclerosis. Arterioscler Thromb Vasc Biol 2014; 35:323-31. [PMID: 25524771 DOI: 10.1161/atvbaha.114.304878] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE Macrophage foam cell formation is a key feature of atherosclerosis. Recent studies have shown that specific microRNAs (miRs) are regulated in modified low-density lipoprotein-treated macrophages, which can affect the cellular cholesterol homeostasis. Undertaking a genome-wide screen of miRs regulated in primary macrophages by modified low-density lipoprotein, miR-302a emerged as a potential candidate that may play a key role in macrophage cholesterol homeostasis. APPROACH AND RESULTS The objective of this study was to assess the involvement of miR-302a in macrophage lipid homeostasis and if it can influence circulating lipid levels and atherosclerotic development when it is inhibited in a murine atherosclerosis model. We found that transfection of primary macrophages with either miR-302a or anti-miR-302a regulated the expression of ATP-binding cassette (ABC) transporter ABCA1 mRNA and protein. Luciferase reporter assays showed that miR-302a repressed the 3' untranslated regions (UTR) activity of mouse Abca1 by 48% and human ABCA1 by 45%. In addition, transfection of murine macrophages with miR-302a attenuated cholesterol efflux to apolipoprotein A-1 (apoA-1) by 38%. Long-term in vivo administration of anti-miR-302a to mice with low-density lipoprotein receptor deficiency (Ldlr(-/-)) fed an atherogenic diet led to an increase in ABCA1 in the liver and aorta as well as an increase in circulating plasma high-density lipoprotein levels by 35% compared with that of control mice. The anti-miR-302a-treated mice also displayed reduced atherosclerotic plaque size by ≈25% and a more stable plaque morphology with reduced signs of inflammation. CONCLUSIONS These studies identify miR-302a as a novel modulator of cholesterol efflux and a potential therapeutic target for suppressing atherosclerosis.
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Affiliation(s)
- Svenja Meiler
- From the Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii, Honolulu (S.M., Y.B., E.T., K.S., W.A.B.); Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, The Netherlands (S.M.); and Kazan Federal University, Kazan, Russia (W.A.B.)
| | - Yvonne Baumer
- From the Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii, Honolulu (S.M., Y.B., E.T., K.S., W.A.B.); Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, The Netherlands (S.M.); and Kazan Federal University, Kazan, Russia (W.A.B.)
| | - Emma Toulmin
- From the Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii, Honolulu (S.M., Y.B., E.T., K.S., W.A.B.); Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, The Netherlands (S.M.); and Kazan Federal University, Kazan, Russia (W.A.B.)
| | - Kosal Seng
- From the Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii, Honolulu (S.M., Y.B., E.T., K.S., W.A.B.); Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, The Netherlands (S.M.); and Kazan Federal University, Kazan, Russia (W.A.B.)
| | - William A Boisvert
- From the Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii, Honolulu (S.M., Y.B., E.T., K.S., W.A.B.); Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, The Netherlands (S.M.); and Kazan Federal University, Kazan, Russia (W.A.B.).
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Kang MH, Zhang LH, Wijesekara N, de Haan W, Butland S, Bhattacharjee A, Hayden MR. Regulation of ABCA1 protein expression and function in hepatic and pancreatic islet cells by miR-145. Arterioscler Thromb Vasc Biol 2013; 33:2724-32. [PMID: 24135019 DOI: 10.1161/atvbaha.113.302004] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Accepted: 10/04/2013] [Indexed: 12/18/2022]
Abstract
OBJECTIVE The ATP-binding cassette transporter A1 (ABCA1) protein maintains cellular cholesterol homeostasis in several different tissues. In the liver, ABCA1 is crucial for high-density lipoprotein biogenesis, and in the pancreas ABCA1 can regulate insulin secretion. In this study, our aim was to identify novel microRNAs that regulate ABCA1 expression in these tissues. APPROACH AND RESULTS We combined multiple microRNA prediction programs to identify 8 microRNAs that potentially regulate ABCA1. A luciferase reporter assay demonstrated that 5 of these microRNAs (miR-148, miR-27, miR-144, miR-145, and miR-33a/33b) significantly repressed ABCA1 3'-untranslated region activity with miR-145 resulting in one of the larger decreases. In hepatic HepG2 cells, miR-145 can regulate both ABCA1 protein expression levels and cholesterol efflux function. In murine islets, an increase in miR-145 expression decreased ABCA1 protein expression, increased total islet cholesterol levels, and decreased glucose-stimulated insulin secretion. Inhibiting miR-145 produced the opposite effect of increasing ABCA1 protein levels and improving glucose-stimulated insulin secretion. Finally, increased glucose levels in media significantly decreased miR-145 levels in cultured pancreatic beta cells. These findings suggest that miR-145 is involved in glucose homeostasis and is regulated by glucose concentration. CONCLUSIONS Our studies demonstrate that miR-145 regulates ABCA1 expression and function, and inhibiting this microRNA represents a novel strategy for increasing ABCA1 expression, promoting high-density lipoprotein biogenesis in the liver, and improving glucose-stimulated insulin secretion in islets.
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Affiliation(s)
- Martin H Kang
- From the Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, BC, Canada
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Rotllan N, Ramírez CM, Aryal B, Esau CC, Fernández-Hernando C. Therapeutic silencing of microRNA-33 inhibits the progression of atherosclerosis in Ldlr-/- mice--brief report. Arterioscler Thromb Vasc Biol 2013; 33:1973-7. [PMID: 23702658 DOI: 10.1161/atvbaha.113.301732] [Citation(s) in RCA: 139] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
OBJECTIVE To study the efficacy of anti-miRNA-33 therapy on the progression of atherosclerosis. APPROACH AND RESULTS Ldlr(-/-) mice were injected subcutaneously with PBS, control, or anti-miR-33 oligonucleotides weekly and fed a Western diet for 12 weeks. At the end of treatment, the expression of miR-33 target genes was increased in the liver and aorta, demonstrating effective inhibition of miR-33 function. Interestingly, plasma high-density lipoprotein (HDL)-cholesterol was significantly increased in anti-miR-33-treated mice but only when they were fed a chow diet. However, HDL isolated from anti-miR-33-treated mice showed an increase cholesterol efflux capacity compared with HDL isolated from nontargeting oligonucleotide-treated mice. Analysis of atherosclerosis revealed a significant reduction of plaque size and macrophage content in mice receiving anti-miR-33. In contrast, no differences in collagen content and necrotic areas were observed among the 3 groups. CONCLUSIONS Long-term anti-miR-33 therapy significantly reduces the progression of atherosclerosis and improves HDL functionality. The antiatherogenic effect is independent of plasma HDL-cholesterol levels.
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Affiliation(s)
- Noemi Rotllan
- Department of Medicine, Leon H Charney Division of Cardiology and Cell Biology and the Marc and Ruti Bell Vascular Biology and Disease Program, New York University School of Medicine, New York, NY, USA
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