Long‐term therapeutic silencing of miR‐33 increases circulating triglyceride levels and hepatic lipid accumulation in mice

EMBO Molecular Medicine

Leigh Goedeke⁵  Alessandro Salerno²  Cristina M Ramírez⁵  Liang Guo²  Ryan M Allen¹  Xiaoke Yin³  Sarah R Langley³  Christine Esau⁴  Amarylis Wanschel²  Edward A Fisher²  Yajaira Suárez⁵  Angel Baldán¹  Manuel Mayr³ 

[1] Edward A. Doisy Department of Biochemistry and Molecular Biology, Center for Cardiovascular Research, Saint Louis University School of Medicine, Saint Louis, MO, USA;Leon H. Charney Division of Cardiology, Department of Medicine, New York University School of Medicine, New York, NY, USA;King's British Heart Foundation Centre, King's College London, London, UK;Regulus Therapeutics, San Diego, CA, USA;Vascular Biology and Therapeutics Program, Yale University School of Medicine, New Haven, CT, USA

关键词: cholesterol;    fatty acids;    hepatic steatosis;    microRNA;   

DOI  :  10.15252/emmm.201404046

来源: Wiley

【 摘 要 】

Abstract

Plasma high-density lipoprotein (HDL) levels show a strong inverse correlation with atherosclerotic vascular disease. Previous studies have demonstrated that antagonism of miR-33 in vivo increases circulating HDL and reverse cholesterol transport (RCT), thereby reducing the progression and enhancing the regression of atherosclerosis. While the efficacy of short-term anti-miR-33 treatment has been previously studied, the long-term effect of miR-33 antagonism in vivo remains to be elucidated. Here, we show that long-term therapeutic silencing of miR-33 increases circulating triglyceride (TG) levels and lipid accumulation in the liver. These adverse effects were only found when mice were fed a high-fat diet (HFD). Mechanistically, we demonstrate that chronic inhibition of miR-33 increases the expression of genes involved in fatty acid synthesis such as acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) in the livers of mice treated with miR-33 antisense oligonucleotides. We also report that anti-miR-33 therapy enhances the expression of nuclear transcription Y subunit gamma (NFYC), a transcriptional regulator required for DNA binding and full transcriptional activation of SREBP-responsive genes, including ACC and FAS. Taken together, these results suggest that persistent inhibition of miR-33 when mice are fed a high-fat diet (HFD) might cause deleterious effects such as moderate hepatic steatosis and hypertriglyceridemia. These unexpected findings highlight the importance of assessing the effect of chronic inhibition of miR-33 in non-human primates before we can translate this therapy to humans.

Synopsis

Although short-term anti-miR-33 therapy was reported to increase circulating HDL-cholesterol and reduce atherosclerosis, long-term adverse effects are here shown for the first time in mice fed a high-fat diet to result in hypertriglyceridemia and moderate hepatic steatosis.

• The effect of long-term inhibition of miR-33 was determined in mice fed a chow diet and high-fat diet.
• Chronic therapeutic silencing of miR-33 increased circulating triglycerides and lipid accumulation in the livers of mice fed a high-fat diet.
• miR-33 inhibition raised the expression of genes involved in fatty acid synthesis and lipid metabolism.
• Further studies are warranted to understand the complex gene regulatory network controlled by miR-33.

【 授权许可】

CC BY   
© 2014 The Authors. Published under the terms of the CC BY 4.0 license

Creative Commons Attribution 4.0 License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.