Department of Gastroenterology, Changhai Hospital, Naval Medical University, Shanghai, China; Department of Gastroenterology, the General Hospital of Central Theater Command, Wuhan, China.
Department of Gastroenterology, Changhai Hospital, Naval Medical University, Shanghai, China.
Int Immunopharmacol. 2023 Aug;121:110447. doi: 10.1016/j.intimp.2023.110447. Epub 2023 Jun 8.
BACKGROUND & AIM: Exosomes are effective mediators of cell-to-cell interactions and transport several regulatory molecules, including microRNAs (miRNAs), involved in diverse fundamental biological processes. The role of macrophage-derived exosomes in the development of inflammatory bowel disease (IBD) has not been previously reported. This study investigated specific miRNAs in macrophage-derived exosomes in IBD and their molecular mechanism.
A dextran sulfate sodium (DSS)-induced IBD mouse model was established. The culture supernatant of murine bone marrow-derived macrophages (BMDMs) cultured with or without lipopolysaccharide (LPS) was used for isolating exosomes, which were subjected to miRNA sequencing. Lentiviruses were used to alter miRNA expression and investigate the role of macrophage-derived exosomal miRNAs. Both mouse and human organoids were co-cultured with macrophages in a Transwell system to model cellular IBD in vitro.
LPS-induced macrophages released exosomes containing various miRNAs and exacerbated IBD. Based on miRNA sequencing of macrophage-derived exosomes, miR-223 was selected for further analysis. Exosomes with upregulated miR-223 expression contributed to the exacerbation of intestinal barrier dysfunction in vivo, which was further verified using both mouse and human colon organoids. Furthermore, time-dependent analysis of the mRNAs in DSS-induced colitis mouse tissue and miR-223 target gene prediction were performed to select the candidate gene, resulting in the identification of the barrier-related factor Tmigd1.
Macrophage-derived exosomal miR-223 has a novel role in the progression of DSS-induced colitis by inducing intestinal barrier dysfunction through the inhibition of TMIGD1.
外泌体是细胞间相互作用的有效介质，可转运多种调节分子，包括参与多种基本生物过程的 microRNAs（miRNAs）。巨噬细胞衍生的外泌体在炎症性肠病（IBD）中的作用尚未见报道。本研究探讨了 IBD 中巨噬细胞衍生的外泌体中的特定 miRNAs 及其分子机制。
建立葡聚糖硫酸钠（DSS）诱导的 IBD 小鼠模型。用或不用脂多糖（LPS）培养的鼠骨髓来源巨噬细胞（BMDM）的培养上清液用于分离外泌体，并进行 miRNA 测序。慢病毒用于改变 miRNA 表达并研究巨噬细胞衍生的外泌体 miRNA 的作用。在 Transwell 系统中，将小鼠和人类类器官与巨噬细胞共培养，以体外模拟细胞 IBD。
LPS 诱导的巨噬细胞释放含有各种 miRNAs 的外泌体，加重了 IBD。基于巨噬细胞衍生的外泌体 miRNA 测序，选择 miR-223 进行进一步分析。上调 miR-223 表达的外泌体有助于体内肠道屏障功能障碍的加重，这在使用小鼠和人类结肠类器官进一步验证。此外，对 DSS 诱导的结肠炎小鼠组织中 mRNAs 的时间依赖性分析和 miR-223 靶基因预测进行了分析，以选择候选基因，从而确定了与屏障相关的基因 Tmigd1。
巨噬细胞衍生的外泌体 miR-223 通过抑制 TMIGD1 诱导肠道屏障功能障碍，在 DSS 诱导的结肠炎进展中具有新的作用。
