Enna Liu; Zheng Li; Yan Zhang; Kuisheng Chen
Abstract
Background: Macrophage polarization plays a critical role in determining the inflammatory states. Hepcidin is a key negative regulator of iron homeostasis and functions. Although hepcidin has been shown to affect ferroportin expression in macrophages, whether it affects macrophage polarization is still ...
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Background: Macrophage polarization plays a critical role in determining the inflammatory states. Hepcidin is a key negative regulator of iron homeostasis and functions. Although hepcidin has been shown to affect ferroportin expression in macrophages, whether it affects macrophage polarization is still largely unknown. Objective: To address whether hepcidin induces macrophage polarization. Methods: The expression of iNOS and CD206, and the ratio of IFN-γ vs IL-4 in THP-1 derived macrophages upon hepcidin stimulation were evaluated. Further detected was the percentage of CD16+ M1, CD23+ M1, CD10+ M2 and CCL22+ M2 cells in monocyte derived macrophages. Results: M1 associated molecules were increased in hepcidin-treated cells, yet M2 associated molecules were increased when hepcidin was neutralized. Concomitantly, we observed a significant increase in IRF3 phosphorylation in hepcidin-stimulated cells. However, STAT6 phosphorylation with hepcidin was neutralized. Conclusion: Hepcidin is able to induce macrophage polarization towards M1 type, and might be utilized as a potential M1 macrophage agonist in clinical practice.
Gege Li; Jiahui Pan; Qiuling Tang; Xinchan Liu; Liuran Wang; Yang Meng; Weixian Yu
Abstract
Background: C5areceptor antagonistPMX205 is a synthetic hexapeptidecapable of blocking C5a-C5a receptor (C5aR) axis by simulating C5a active C-terminal amino acid residues. This hexapeptide presents good anti-inflammatory effects in a myriad inflammation models. The anti-inflammatory effect of PMX205 ...
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Background: C5areceptor antagonistPMX205 is a synthetic hexapeptidecapable of blocking C5a-C5a receptor (C5aR) axis by simulating C5a active C-terminal amino acid residues. This hexapeptide presents good anti-inflammatory effects in a myriad inflammation models. The anti-inflammatory effect of PMX205 on periodontitis is yet to be fully fathomed. Objective: To examine the anti-inflammatory effects of PMX205 on RAW264.7 murine macrophages exposed togingipain extracts and Porphyromonas gingivalis (P. gingivalis). Methods: MTT assay was carried out so as to specify the cytotoxicity of PMX205. RAW264.7 cells were co-cultured in vitro with gingipain extracts or P. gingivalis to simulate the periodontitis inflammatory milieu. Real-time quantitative PCR, ELISA and Griess assay were performed in order to detect tumor necrosis factor-α (TNF-α), IL-6, IL-23, nitric oxide (NO), IL-10, transforming growth factor-β1 (TGF-β1), andarginase-1 (Arg-1). Furthermore, phagocytosis assay was done to evaluate the phagocytic capacity of RAW 264.7 cells. Finally, western blot analysis was conducted to evaluate myeloid differentiation factor 88 (MyD88). Results: PMX205 increased the expression levels of bacteriostatic substances (NO and IL-23) and anti-inflammatory cytokines (TGF-β1, IL-10 and Arg-1); however, it reduced the expression levels of proinflammatory cytokines TNF-α and IL-6once RAW 264.7 macrophages were stimulated via gingipain extracts or P. gingivalis. In addition, PMX205 promoted the macrophage phagocytosis and down-regulated protein expression of MyD88. Conclusion: PMX205 has recognizable anti-inflammatory effects in RAW 264.7 cell inflammation model, a finding which probably opens doors to future investigations on new targets for the prevention and treatment of chronic periodontitis.
