Geniposide Plays an Anti-inflammatory Role via Regulating TLR4 and Downstream Signaling Pathways in Lipopolysaccharide-Induced Mastitis in Mice
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Geniposide is a medicine isolated from Gardenia jasminoides Ellis, which is a traditional Chinese herb that is widely used in Asia for the treatment of inflammation, brain diseases, and hepatic disorders. Mastitis is a highly prevalent and important infectious disease. In this study, we used a lipopolysaccharide (LPS)-induced mouse mastitis model and LPS-stimulated primary mouse mammary epithelial cells (mMECs) to explore the anti-inflammatory effect and the mechanism of action of geniposide. Using intraductal injection of LPS as a mouse model of mastitis, we found that geniposide significantly reduced the infiltration of inflammatory cells and downregulated the production of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6). To further investigate the anti-inflammatory mechanism, we used LPS-stimulated mMECs as an in vitro mastitis model. The results of enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qRT-PCR) showed that geniposide inhibited the expression of TNF-α, IL-1β, and IL-6 in a dose-dependent manner. Western blot analysis demonstrated that geniposide could suppress the phosphorylation of inhibitory kappa B (IκBα), nuclear factor-κB (NF-κB), p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). Geniposide also inhibited the expression of toll-like receptor 4 (TLR4) in the LPS-stimulated mMECs. In conclusion, geniposide exerted its anti-inflammatory effect by regulating TLR4 expression, which affected the downstream NF-κB and mitogen-activated protein kinase (MAPK) signaling pathways. Thus, geniposide may be a potential drug for mastitis therapy.
KEY WORDSgeniposide lipopolysaccharide (LPS) anti-inflammatory toll-like receptor nuclear factor-κB (NF-κB) mitogen-activated protein kinase (MAPK)
This work was supported by a grant from the National Natural Science Foundation of China (Nos. 31272622, 31201925), the Research Fund for the Doctoral Program of Higher Education of China (Nos. 20110061130010, 20120061120098), and Jilin Province Science Foundation for Youths (No. 20130522087JH).
Conflict of Interest
All authors declare that they have no conflict of interest.
- 4.Opal, S.M., P.J. Scannon, J.L. Vincent, M. White, S.F. Carroll, J.E. Palardy, N.A. Parejo, J.P. Pribble, and J.H. Lemke. 1999. Relationship between plasma levels of lipopolysaccharide (LPS) and LPS-binding protein in patients with severe sepsis and septic shock. Journal of Infectious Diseases 180(5): 1584–1589.PubMedCrossRefGoogle Scholar
- 5.Oliver, S., and L. Calvinho. 1995. Influence of inflammation on mammary gland metabolism and milk composition. Journal of Animal Science 73(suppl 2): 18–33.Google Scholar
- 9.Wu, S.Y., G.F. Wang, Z.Q. Liu, J.J. Rao, L. Lu, W. Xu, S.G. Wu, and J.J. Zhang. 2009. Effect of geniposide, a hypoglycemic glucoside, on hepatic regulating enzymes in diabetic mice induced by a high-fat diet and streptozotocin. Acta Pharmacologica Sinica 30(2): 202–208.PubMedCrossRefPubMedCentralGoogle Scholar
- 10.Liu, H.T., J.L. He, W.M. Li, Z. Yang, Y.X. Wang, J. Yin, Y.G. Du, and C. Yu. 2010. Geniposide inhibits interleukin-6 and interleukin-8 production in lipopolysaccharide-induced human umbilical vein endothelial cells by blocking p38 and ERK1/2 signaling pathways. Inflammation Research : Official Journal of the European Histamine Research Society 59(6): 451–461.CrossRefGoogle Scholar
- 12.Fu, Y., B. Liu, J. Liu, Z. Liu, D. Liang, F. Li, D. Li, Y. Cao, X. Zhang, N. Zhang, et al. 2012. Geniposide, from Gardenia jasminoides Ellis, inhibits the inflammatory response in the primary mouse macrophages and mouse models. International Immunopharmacology 14(4): 792–798.PubMedCrossRefGoogle Scholar
- 13.Barham W, Sherrill T, Connelly L, Blackwell T, Yull F. 2012. Intraductal injection of LPS as a mouse model of mastitis: signaling visualized via an NF-κB reporter transgenic. Journal of visualized experiments: JoVE (67).Google Scholar
- 17.Fu, Y., L. Bo, X. Feng, Z. Liu, D. Liang, F. Li, D. Li, Y. Cao, S. Feng, and X. Zhang. 2012. Lipopolysaccharide increases Toll-like receptor 4 and downstream Toll-like receptor signaling molecules expression in bovine endometrial epithelial cells. Veterinary Immunology and Immunopathology 151: 20–27.PubMedCrossRefGoogle Scholar
- 18.Li, F., D. Liang, Z. Yang, T. Wang, W. Wang, X. Song, M. Guo, E. Zhou, D. Li, Y. Cao, et al. 2013. Astragalin suppresses inflammatory responses via down-regulation of NF-kappaB signaling pathway in lipopolysaccharide-induced mastitis in a murine model. International Immunopharmacology 17(2): 478–482.PubMedCrossRefGoogle Scholar
- 19.Liang, D., Y. Sun, Y. Shen, F. Li, X. Song, E. Zhou, F. Zhao, Z. Liu, Y. Fu, M. Guo, et al. 2013. Shikonin exerts anti-inflammatory effects in a murine model of lipopolysaccharide-induced acute lung injury by inhibiting the nuclear factor-kappaB signaling pathway. International Immunopharmacology 16(4): 475–480.PubMedCrossRefGoogle Scholar
- 29.Guo, M.Y., N.S. Zhang, D.P. Li, D.J. Liang, Z.C. Liu, F.Y. Li, Y.H. Fu, Y.G. Cao, X.M. Deng, and Z.T. Yang. 2013. Baicalin plays an anti-inflammatory role through reducing nuclear factor-kappa B and p38 phosphorylation in S. aureus-induced mastitis. International Immunopharmacology 16(2): 125–130.PubMedCrossRefGoogle Scholar
- 31.Demeyere, K., Q. Remijsen, D. Demon, K. Breyne, S. Notebaert, F. Boyen, C.J. Guérin, P. Vandenabeele, and E. Meyer. 2013. Escherichia coli induces bovine neutrophil cell death independent from caspase-3/-7/-1, but with phosphatidylserine exposure prior to membrane rupture. Veterinary Immunology and Immunopathology 153(1): 45–56.PubMedCrossRefGoogle Scholar
- 34.Muzio, M., J. Ni, P. Feng, and V.M. Dixit. 2013. IRAK (Pelle) family member IRAK-2 and MyD88 as proximal mediators of IL-1 signaling (reprinted from Science, vol 278, pg 1612-1615, 1997). Journal of Immunology 190(1): 16–19.Google Scholar
- 38.Goldammer, T., H. Zerbe, A. Molenaar, H.-J. Schuberth, R. Brunner, S. Kata, and H.-M. Seyfert. 2004. Mastitis increases mammary mRNA abundance of β-defensin 5, toll-like-receptor 2 (TLR2), and TLR4 but not TLR9 in cattle. Clinical and Diagnostic Laboratory Immunology 11(1): 174–185.PubMedPubMedCentralGoogle Scholar