MicroRNA-24 Modulates Staphylococcus aureus-Induced Macrophage Polarization by Suppressing CHI3L1.
Macrophages play a crucial role in host innate anti-Staphylococcus aureus defense, which is tightly regulated by multiple factors, including microRNAs. A recent study showed that miR-24 plays an important role in macrophage polarization. Here, we investigated the biological function of miR-24 in S. aureus-stimulated macrophages. The results revealed that miR-24 expression was significantly decreased in both human and mouse macrophage cell lines with S. aureus stimulation in a time-dependent manner. Moreover, miR-24 overexpression significantly decreased the production of M1 phenotype markers, such as IL-6, iNOS, TNF-α, CD86, and CD80, whereas it increased the production of M2 markers, such as Arg1, CCL17, CCL22, CD163, and CD206, in S. aureus-stimulated macrophages. Conversely, knockdown of miR-24 promoted M1 macrophage polarization but diminished M2 macrophage polarization in S. aureus-stimulated macrophages. Furthermore, CHI3L1 was predicted as a target gene of miR-24 using bioinformatics software and identified by luciferase reporter assay. Additionally, miR-24 overexpression inhibited CHI3L1 expression and downregulated the downstream MAPK pathway in S. aureus-stimulated macrophages. Finally, CHI3L1 overexpression rescued macrophage polarization and MAPK pathway inhibition induced by miR-24 mimic transfection in S. aureus-stimulated macrophages. In conclusion, the data suggest that miR-24 serves as a molecular regulator in S. aureus-induced macrophage polarization through targeting of CHI3L1 and regulation of the MAPK pathway, which may provide a promising therapeutic target for S. aureus-related infections and inflammatory diseases.
['Jingjing|Zhang|Z|', 'Nan|Zhang|Z|', 'Wei|Wu|W|', 'Qinghe|Guo|G|', 'Weijuan|Wang|W|', 'Peng|Wang|W|', 'Xiangpeng|Wang|W|']
D000818:Animals D002460:Cell Line D000071451:Chitinase-3-Like Protein 1 D006801:Humans D008262:Macrophage Activation D008264:Macrophages D051379:Mice D035683:MicroRNAs D020929:Mitogen-Activated Protein Kinase Kinases D013211:Staphylococcus aureus
macrophage polarization CHI3L1 miR-24 MAPK pathway Staphylococcus aureus