This study reveals the central role of the lncRNA MIR181A1HG in vascular endothelial inflammation, providing novel experimental design insights into the non-coding RNA regulatory mechanisms of atherosclerosis, and suggesting that targeting the NLRP3 signaling axis may have therapeutic potential.
Literature Overview
The study titled 'LncRNA MIR181A1HG Deficiency Attenuates Vascular Inflammation and Atherosclerosis,' published in the journal Circulation Research, systematically investigates the function and molecular mechanisms of the long non-coding RNA MIR181A1HG in atherosclerosis progression. The study finds that MIR181A1HG is significantly upregulated in atherosclerotic plaques from both humans and mice, predominantly expressed in endothelial cells (ECs), and its deletion markedly reduces vascular inflammation and plaque formation. Using various genetically modified animal models, single-cell RNA sequencing (scRNA-seq), and RNA-protein interaction assays, the authors demonstrate that MIR181A1HG acts as a 'molecular trap' by sequestering the transcription factor Foxp1, thereby relieving its repression of pro-inflammatory genes such as NLRP3, ultimately promoting endothelial activation and atherosclerosis. This finding expands our understanding of the regulatory network of lncRNAs in cardiovascular diseases.Background Knowledge
Atherosclerosis is an arterial wall disease characterized by chronic vascular inflammation and is the primary pathological basis for cardiovascular events such as myocardial infarction and stroke. Current treatments mainly focus on lipid-lowering; however, increasing evidence indicates that inflammatory pathways are key drivers independent of lipids. Although the CANTOS trial targeting IL-1β has demonstrated the feasibility of anti-inflammatory therapy, more precise intervention targets remain lacking. Non-coding RNAs, particularly long non-coding RNAs (lncRNAs), have recently been found to widely participate in vascular biological processes, but the functions of most lncRNAs remain unclear, and their mechanisms are often complex, involving chromatin remodeling, transcriptional regulation, or acting as miRNA sponges. MIR181A1HG is located adjacent to the miR-181a1/b1 locus, and miR-181b has been reported to inhibit the NF-κB pathway and reduce vascular inflammation, so it remains unclear whether this lncRNA functions independently. This study focuses on systematically elucidating the role of MIR181A1HG in endothelial cells and its interactions with key factors such as the NLRP3 inflammasome and Foxp1, thereby revealing a novel lncRNA-mediated inflammatory regulatory axis.
Research Methods and Experiments
The study employed various animal models and cellular systems for functional validation. First, the authors generated MIR181A1HG−/−ApoE−/− mice and found that after high-fat diet feeding, the plaque area in the aorta and aortic root was significantly reduced, with decreased macrophage and T cell infiltration in plaques and increased smooth muscle cells and collagen, indicating more stable plaques. Bone marrow transplantation experiments showed that deletion of MIR181A1HG in myeloid cells did not affect atherosclerosis progression, indicating its effect primarily depends on non-immune cells, particularly endothelial cells. To confirm cell-autonomous effects, the authors used an AAV system to achieve endothelial-specific overexpression of MIR181A1HG, which significantly exacerbated plaque formation, and this phenotype was reversed by the NLRP3 inhibitor MCC950, demonstrating that NLRP3 is a key downstream effector.
Mechanistically, the authors identified Foxp1 as a direct binding protein of MIR181A1HG through RNA pull-down and mass spectrometry, and confirmed via RIP and CUT&Tag assays that MIR181A1HG binds to the forkhead domain of Foxp1 via nucleotides 1371–1440, thereby 'trapping' it away from promoter regions of genes such as NLRP3, CASP1, and IL1B, thus relieving transcriptional repression. Furthermore, single-cell RNA-seq analysis revealed that upon MIR181A1HG deletion, pro-inflammatory pathways (e.g., TNF, NF-κB) were significantly downregulated in endothelial cell clusters, while anti-inflammatory signals were enhanced, further supporting its central role in endothelial inflammation regulation.Key Conclusions and Perspectives
Research Significance and Prospects
This study not only elucidates the mechanism by which the lncRNA MIR181A1HG promotes inflammation in atherosclerosis but also proposes a novel model in which lncRNAs regulate inflammatory genes by 'trapping' transcription factors. This finding provides a theoretical basis for developing therapeutic strategies targeting non-coding RNAs; for example, using ASOs or small molecules to inhibit MIR181A1HG may represent a new anti-inflammatory approach.
From a drug development perspective, this study supports the rationale for targeting NLRP3 and suggests that MIR181A1HG expression levels could serve as a biomarker for patient stratification or treatment response prediction. Moreover, due to its endothelial-specific expression, targeting MIR181A1HG may offer high tissue specificity and reduce systemic side effects.
In terms of disease modeling, the MIR181A1HG−/−ApoE−/− mouse can serve as a valuable tool model for studying endothelial-specific anti-inflammatory mechanisms. Combined with single-cell multi-omics technologies, it will help further dissect cellular interaction networks within the plaque microenvironment.
Conclusion
This study systematically elucidates the pro-inflammatory mechanism of the lncRNA MIR181A1HG in atherosclerosis, whereby it acts as a molecular trap to sequester the transcriptional repressor Foxp1, thereby relieving inhibition of the NLRP3 inflammasome and driving endothelial activation and monocyte infiltration. This discovery not only expands our understanding of lncRNA-mediated regulation in cardiovascular diseases but also provides new potential therapeutic targets for atherosclerosis. From a translational perspective, MIR181A1HG may emerge as a future biomarker or drug target for anti-inflammatory therapy, particularly in patient populations with hyperactivated inflammatory signaling. Combined with existing ApoE−/− models and gene-editing technologies, more precise disease models can be developed for drug efficacy evaluation. This study lays the foundation for a vascular inflammatory regulatory network centered on non-coding RNAs, potentially advancing the treatment paradigm for cardiovascular diseases from 'lipid-lowering only' to 'dual control of lipids and inflammation,' with significant implications for improving long-term outcomes in atherosclerosis patients.
