Related Experiment Video
Updated: Feb 10, 2026
Mesenchymal Stem Cell Regulation of Macrophage Phagocytosis; Quantitation and Imaging
Published on: July 16, 2021
MiR-155 inhibits transformation of macrophages into foam cells via regulating CEH expression
Fengxiang Zhang1, Jinsong Zhao1, Dapeng Sun1
1Department of Cardiothoracic Surgery, The First Affiliated Hospital of JINZHOU Medical University, Jinzhou, 121001, China.
Abstract:
MiR-155 can inhibit the formation of atherosclerosis by interfering with the transformation of macrophages into foam cells that plays a critical role in the pathogenesis of atherosclerosis, but the precise mechanisms of miR-155 are still unknown. Herein, we observed that mRNA and protein expression levels of CEH were significantly upregulated in a dose- and time-dependent manner by transfected with miR-155 mimics in THP-1 macrophages. Further studies showed that overexpression of miR-155 can significantly inhibit foam cells formation, reduce intracellular CE accumulation and enhance the efflux of FC and cholesterol, result in a decrease of intracellular lipid accumulation; while this effect was significantly reversed by siCEH. Meanwhile, we found that Tim-3 is associated with miR-155-mediated CEH expression in THP-1 macrophage-derived foam cells. Overexpression of Tim-3 can attenuate miR-155-mediated CEH induction. Taken together, our findings demonstrated that miR-155 can inhibit the transformation of macrophages into foam cells by enhancing CEH signaling pathway in macrophages, this effect is likely to be achieved by inhibiting the expression of Tim-3.
Insights
MicroRNA-155 (miR-155) inhibits atherosclerosis by preventing macrophage foam cell formation. It enhances cholesterol efflux by upregulating CEH, likely by downregulating Tim-3 expression.
Area of Science:
- Biochemistry
- Molecular Biology
- Cardiovascular Research
Background:
- Atherosclerosis pathogenesis involves macrophage transformation into foam cells.
- The precise mechanisms of microRNA-155 (miR-155) in this process are not fully understood.
Purpose of the Study:
- To elucidate the role and mechanism of miR-155 in regulating macrophage foam cell formation.
- To investigate the relationship between miR-155, CEH, and Tim-3 in macrophages.
Main Methods:
- Transfection of THP-1 macrophages with miR-155 mimics and siCEH.
- Quantitative analysis of mRNA and protein expression levels.
- Assessment of intracellular cholesterol accumulation and efflux.
Main Results:
- miR-155 mimics upregulated CEH mRNA and protein expression in a dose- and time-dependent manner.
- Overexpression of miR-155 inhibited foam cell formation, reduced CE accumulation, and enhanced cholesterol efflux.
- siCEH reversed the effects of miR-155, and Tim-3 was found to attenuate miR-155-mediated CEH induction.
Conclusions:
- miR-155 inhibits macrophage transformation into foam cells by enhancing the CEH signaling pathway.
- This effect is mediated by the inhibition of Tim-3 expression, providing a novel therapeutic target for atherosclerosis.
Related Concept Videos
02:24Regulation of Expression Occurs at Multiple Steps
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
02:24Regulation of Expression Occurs at Multiple Steps
01:23Regulation of Expression at Multiple Steps
01:33Bacterial Transformation
Griffith made an unexpected discovery when he killed the pathogenic strain and mixed its remains with the live, non-pathogenic strain. Not only did the mixture kill host mice, but it also contained living pathogenic bacteria that...
01:27Constitutive and Regulated Gene Expression
01:46Epigenetic Regulation