Molecular Mechanism of TNIP3 in Regulating M2 Polarization of Macrophages: A Study Based on the Inhibitory Effect of the NF-κB Signaling Pathway

Objective To explore the regulatory effect of TNIP3 on the M2 polarization of macrophages and its molecular mechanism.Methods Macrophage models with TNIP3 overexpression (OV-M0) and TNIP3 interference (si-M0) were constructed. Meanwhile, untreated macrophages (M0) and M2 macrophages (M2) were set as control groups. qPCR and immunofluorescence techniques for detecting the expression levels of M2 macrophage markers. Western blot was applied to analyze the activation status of the NF-κB signaling pathway. RNA-Seq was used to screen the differentially expressed genes (DEGs) regulated by TNIP3, and GO functional annotation and KEGG pathway enrichment analysis were carried out.Results (1) Phenotypic analysis showed that compared with the si-M0, M0, and M2 groups, the expression of the M2 marker CD206 in the OV-M0 group was significantly increased (P < 0.05). Notably, Arg-1, TGF-β, and IL-10 demonstrated significantly enhanced transcriptional activity in experimental groups compared to controls. (2) Western blot detection revealed that the p-P65/P65 ratio in the OV-M0 group was significantly decreased, suggesting that the NF-κB pathway was inhibited. (3) RNA Seq analysis showed that a total of 2923 differentially expressed genes were identified in the OV-M0 group, including 1297 upregulated genes and 1626 downregulated genes. Comparing the differences between M2 group vs M0 group and OV-M0 group vs M0 group, 535 down regulated genes and 163 up regulated genes were screened, and 15 key differentially expressed genes were ultimately identified; (4) GO and KEGG analysis showed that these differentially expressed genes are mainly involved in biological processes such as immune regulation and cytokine interactions.Conclusion TNIP3 may promote M2 polarization of macrophages by inhibiting the NF - κ B pathway. Transcriptome analysis identified key upregulated genes such as LOC105370202 and KAZALD1, as well as downregulated genes such as C12orf75 and CCNB1, which may participate in the M2 polarization process by regulating the cytokine network.