ORIGINAL RESEARCH article

Front. Immunol.

Sec. Inflammation

Volume 16 - 2025 | doi: 10.3389/fimmu.2025.1601272

This article is part of the Research TopicUnraveling the Molecular Web of Inflammation and Fibrosis: Pathways, Immune Interactions, Epigenetics, and Therapeutic FrontiersView all 7 articles

circ-0001875 downregulation is associated with M1 macrophage activation and lung inflammation in severe asthma

Provisionally accepted
Gege  LiuGege Liu*Jiahao  CaoJiahao CaoYiyan  LinYiyan LinBingyu  LongBingyu LongYanyu  SuYanyu SuGuiqiang  QiuGuiqiang QiuChi  JiangChi JiangYue  WangYue WangXuanna  ZhaoXuanna ZhaoDan  HuangDan HuangDong  WuDong Wu
  • Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong Province, China

The final, formatted version of the article will be published soon.

Background: Asthma is a heterogeneous group of diseases. The mechanism by which dysregulated circRNAs affect severe asthma by regulating macrophage polarization remains unclear.Methods: High-throughput RNA sequencing technology was used to analyze circRNA expression in peripheral blood mononuclear cells (PBMCs) from patients with severe asthma. RT-qPCR and ELISA were used to analyze the expression of inflammatory factors in a mouse model of severe asthma induced by ovalbumin-lipopolysaccharide. The effect of circ-0001875 on macrophage activation and the underlying mechanism were analyzed by RT-qPCR, Western blot, and ELISA. Subsequently, the regulatory relationships among circ-0001875, miR-31-5p, and SP1 were examined through dual luciferase reporter gene assay, and the mechanism by which they regulate macrophage polarization was analyzed by Western blot.Results: Compared with the healthy control group, 420 circRNAs were differentially expressed in PBMCs from patients with severe asthma. Among them, circ-0001875, which was mainly expressed in the cytoplasm of monocytes, was significantly downregulated in asthmatics, especially those with severe disease. circ-0001875 overexpression inhibited M1 macrophage activation in vitro and alleviated lung inflammation in a mouse model of severe asthma.Mechanistically, circ-0001875 promoted SP1 translation by competitively binding to miR-31-5p, thereby reducing its inhibitory effect on SP1 translation; SP1 then inhibited M1 macrophage 删除了: induced polarization, which is associated with severe asthma, through the NF-κB signaling pathway.Conclusions: We found that circ-0001875 plays an important role in regulating M1 macrophage polarization, which is associated with a severe pro-inflammatory response.

Keywords: Severe asthma, circ-0001875, miR-31-5p, Sp1, M1 polarization

Received: 27 Mar 2025; Accepted: 04 Jun 2025.

Copyright: © 2025 Liu, Cao, Lin, Long, Su, Qiu, Jiang, Wang, Zhao, Huang and Wu. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence: Gege Liu, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong Province, China

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