ABSTRACT
Objective:To ascertain whether the immune complexes (ICs) formed by Dengue virus 1 non-structure protein 1 (DENV1 NS1)and its IgG antibodies could mediate passive systemic anaphylaxis (PSA) and to explain the pathogenesis of Dengue hemorrhagic fever or Dengue shock syndrome (DHF/DSS).Methods:The monoclonal antibodies (mAbs) or mAb cocktails from 20 IgG mAbs of DENV1 NS1 prepared in this lab were screened to initiate PSA and passive cutaneous anaphylaxis (PCA) in mice.Meanwhile, the effects of GdCl3 and platelet activating factor ( PAF) antagonist CV-3988 on PSA induced by the NS1-IgG ICs were observed.Results:Two groups of monoclonal antibody cocktails with purified NS 1 were proved to be capable of provoking PCA and PSA in mice,whereas the other mAbs or mAb cocktails could be not .The murine PSA initiated by NS1-IgG(5D25+3B1) ICs could be sig-nificantly inhibited by in vivo treatment with GdCl3 or PAF antagonist CV-3988.Conclusion: The NS1-IgG ICs formed with DENV1 NS1 and IgG mAb cocktails can mediate PSA and PCA ,but not all of ICs formed by DENV 1 NS1 mAbs or mAb cocktails with DENV 1 NS1 can induce PSA ,indicating that it may be related to the special epitopes of DENV 1 NS1.The monocyte/macrophages and PAF may be as major effector cells and the major mediator for PSA induced by NS 1-IgG ICs,respectively.
ABSTRACT
Curcumin is naturally occurring polyphenolic compound found in turmeric and has many pharmacological activities. The present study was undertaken to evaluate anti-allergic inflammatory activity of curcumin, and to investigate its inhibitory mechanisms in immunoglobulin E (IgE)/Ag-induced mouse bone marrow-derived mast cells (BMMCs) and in a mouse model of IgE/Ag-mediated passive systemic anaphylaxis (PSA). Curcumin inhibited cyclooxygenase-2 (COX-2) dependent prostaglandin D2 (PGD2) and 5-lipoxygenase (5-LO) dependent leukotriene C4 (LTC4) generation dose-dependently in BMMCs. To probe the mechanism involved, we assessed the effects of curcumin on the phosphorylation of Syk and its downstream signal molecules. Curcumin inhibited intracellular Ca2+ influx via phospholipase Cgamma1 (PLCgamma1) activation and the phosphorylation of mitogen-activated protein kinases (MAPKs) and the nuclear factor-kappaB (NF-kappaB) pathway. Furthermore, the oral administration of curcumin significantly attenuated IgE/Ag-induced PSA, as determined by serum LTC4, PGD2, and histamine levels. Taken together, this study shows that curcumin offers a basis for drug development for the treatment of allergic inflammatory diseases.
Subject(s)
Animals , Mice , Administration, Oral , Anaphylaxis , Arachidonate 5-Lipoxygenase , Curcuma , Curcumin , Cyclooxygenase 2 , Histamine , Immunoglobulin E , Immunoglobulins , Leukotriene C4 , Mast Cells , Mitogen-Activated Protein Kinases , Phospholipases , Phosphorylation , Prostaglandin D2ABSTRACT
Curcumin is naturally occurring polyphenolic compound found in turmeric and has many pharmacological activities. The present study was undertaken to evaluate anti-allergic inflammatory activity of curcumin, and to investigate its inhibitory mechanisms in immunoglobulin E (IgE)/Ag-induced mouse bone marrow-derived mast cells (BMMCs) and in a mouse model of IgE/Ag-mediated passive systemic anaphylaxis (PSA). Curcumin inhibited cyclooxygenase-2 (COX-2) dependent prostaglandin D2 (PGD2) and 5-lipoxygenase (5-LO) dependent leukotriene C4 (LTC4) generation dose-dependently in BMMCs. To probe the mechanism involved, we assessed the effects of curcumin on the phosphorylation of Syk and its downstream signal molecules. Curcumin inhibited intracellular Ca2+ influx via phospholipase Cgamma1 (PLCgamma1) activation and the phosphorylation of mitogen-activated protein kinases (MAPKs) and the nuclear factor-kappaB (NF-kappaB) pathway. Furthermore, the oral administration of curcumin significantly attenuated IgE/Ag-induced PSA, as determined by serum LTC4, PGD2, and histamine levels. Taken together, this study shows that curcumin offers a basis for drug development for the treatment of allergic inflammatory diseases.