Myricetin attenuates lipopolysaccharide-stimulated activation of mouse bone marrow-derived dendritic cells through suppression of IKK/NF-κB and MAPK signalling pathways.
BACKGROUND
Myricetin is a naturally occurring flavonoid that is found in many fruits, vegetables, teas and medicinal herbs. It has been demonstrated to have anti-inflammatory properties, but, to date, no studies have described the immunomodulatory effects of myricetin on the functions of dendritic cells (DCs). The aim of this study was to evaluate the potential for myricetin to modulate lipopolysaccharide (LPS)-stimulated activation of mouse bone marrow-derived DCs.


RESULTS
Our experimental data showed that treatment with myricetin up to 10 µg mL(-1) does not cause cytotoxicity in cells. Myricetin significantly decreased the secretion of tumour necrosis factor-α, interleukin-6 and interleukin-12p70 by LPS-stimulated DCs. The expression of LPS-induced major histocompatibility class II, CD40 and CD86 on DCs was also inhibited by myricetin, and the endocytic and migratory capacity of LPS-stimulated DCs was blocked by myricentin. In addition, LPS-stimulated DC-elicited allogeneic T-cell proliferation was reduced by myricetin. Moreover, our results confirmed that myricetin attenuates the responses of LPS-stimulated activation of DCs via suppression of IκB kinase/nuclear factor-κB and mitogen-activated protein kinase-dependent pathways.


CONCLUSIONS
Myricetin has novel immunopharmacological activity, and modulation of DCs by myricetin may be an attractive strategy for the treatment of inflammatory and autoimmune disorders, and for transplantation.
Graduate Institute of Immunology, China Medical University, Taichung, Taiwan; Center for Neuropsychiatry, China Medical University Hospital, Taichung, Taiwan.
Ru-Huei
RH
Fu
Shih-Ping
SP
Liu
Ching-Liang
CL
Chu
Ya-Hsien
YH
Lin
Yu-Chen
YC
Ho
Shao-Chih
SC
Chiu
Wei-Yong
WY
Lin
Woei-Cherng
WC
Shyu
Shinn-Zong
SZ
Lin
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology* / Q000627:therapeutic use; D000941:Antigens / Q000378:metabolism; D001853:Bone Marrow / Q000187:drug effects* / Q000378:metabolism; D003713:Dendritic Cells / Q000187:drug effects* / Q000378:metabolism; D005419:Flavonoids / Q000494:pharmacology* / Q000627:therapeutic use; D051550:I-kappa B Kinase / Q000378:metabolism; D007155:Immunologic Factors / Q000494:pharmacology* / Q000627:therapeutic use; D007249:Inflammation / Q000188:drug therapy / Q000276:immunology* / Q000378:metabolism; D007378:Interleukins / Q000378:metabolism; D008070:Lipopolysaccharides; D008810:Mice, Inbred C57BL; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D000097782:NF-kappaB-Inducing Kinase
D000893:Anti-Inflammatory Agents; D000941:Antigens; D005419:Flavonoids; D051550:I-kappa B Kinase; D007155:Immunologic Factors; D007378:Interleukins; D008070:Lipopolysaccharides; D020928:Mitogen-Activated Protein Kinases; D016328:NF-kappa B; D010936:Plant Extracts; D017346:Protein Serine-Threonine Kinases; D014409:Tumor Necrosis Factor-alpha; D000097782:NF-kappaB-Inducing Kinase; C040015:myricetin