Abstract
Objective
The aim of the present study was to investigate the effects of folic acid on the inflammatory responses to lipopolysaccharide (LPS) in RAW264.7 cells and the signal transduction pathways involved.
Methods
RAW264.7 macrophages were used. The production of nitric oxide (NO) was determined by the Griess test. The protein levels and mRNA expression of tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) were determined by ELISA and RT-PCR, respectively. The phosphorylation of mitogen-activated protein kinases (MAPKs) and nuclear nuclear factor-kappa B (NF-κB) p65 protein were analyzed by Western blotting.
Results
Folic acid inhibited LPS-induced production of NO, TNF-α and IL-1β with decreased mRNAs of inducible nitric oxide synthase (iNOS), TNF-α and IL-1β. Further study showed that folic acid inhibited the LPS-induced phosphorylation of MAPKs and the nuclear translocation of NF-κB.
Conclusion
Folic acid inhibits the inflammatory response of RAW 264.7 cells to LPS through inhibiting the MAPKs and NF-κB pathways.




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This work was supported by the National Natural Science Foundation of China (Grant No. 30872101).
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Responsible Editor: Liwu Li.
D. Feng and Y. Zhou are contributed equally to this work.
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Feng, D., Zhou, Y., Xia, M. et al. Folic acid inhibits lipopolysaccharide-induced inflammatory response in RAW264.7 macrophages by suppressing MAPKs and NF-κB activation. Inflamm. Res. 60, 817–822 (2011). https://doi.org/10.1007/s00011-011-0337-2
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DOI: https://doi.org/10.1007/s00011-011-0337-2