title: Inhibition of the antigen-induced activation of RBL-2H3 cells by sinomenine.
abstract: The present study was designed to investigate the effect of sinomenine (SIN), an alkaloid extracted from sinomenium acutum, on the antigen-induced activation of RBL-2H3. For this investigation, the RBL-2H3 cells were sensitized with dinitrophenyl (DNP)-specific IgE overnight in 1.0 ml of Eagle's MEM (EMEM), and varying doses of SIN were added to the culture medium for 30 min and challenged with dinitrophenyl-human serum albumin (DNP-HSA) to induce mast cell degranulation before supernatants were collected. The effects of SIN on antigen-induced release of beta-hexosaminidase were measured by enzymatic assay, calcium influx by FACS, cytokines by ELISA, and signaling events by immunoblotting. The results showed that treatment with SIN was followed by a decrease in FcepsilonRI-mediated mast cell release of beta-hexosaminidase, production of IL-4 and TNF-alpha, phosphorylation of Gab2 (Scaffolding adapter Grb2-associated binder 2), Akt and p38 mitogen-activated protein kinase (MAPK). In addition, SIN had no effect on the phosphorylation of LAT and no significant difference on calcium mobilization was observed between control and SIN treated group. These results suggested that SIN might suppress the antigen-induced activation of RBL-2H3 cells via a Ca2+ independent pathway.
authors.affiliation: Department of Pharmacology, Kobe Pharmaceutical University, Kobe, Hyogo, Japan.
authors.forename: Feng
authors.initials: F
authors.lastname: Huang
authors.forename: Kouya
authors.initials: K
authors.lastname: Yamaki
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Tong
authors.forename: Lianqing
authors.initials: L
authors.lastname: Fu
authors.forename: Ronghua
authors.initials: R
authors.lastname: Zhang
authors.forename: Yu
authors.initials: Y
authors.lastname: Cai
authors.forename: Rie
authors.initials: R
authors.lastname: Yanagisawa
authors.forename: Ken-ichiro
authors.initials: K
authors.lastname: Inoue
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Takano
authors.forename: Shin
authors.initials: S
authors.lastname: Yoshino
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000502:physiology; D000818:Animals; D000941:Antigens / Q000276:immunology*; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D015847:Interleukin-4 / Q000096:biosynthesis; D008407:Mast Cells / Q000187:drug effects* / Q000378:metabolism; D009019:Morphinans / Q000494:pharmacology*; D051381:Rats; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D001619:beta-N-Acetylhexosaminidases / Q000276:immunology / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D000941:Antigens; C490895:GAB2 protein, human; D009019:Morphinans; D014409:Tumor Necrosis Factor-alpha; D015847:Interleukin-4; C009271:sinomenine; D048051:p38 Mitogen-Activated Protein Kinases; D001619:beta-N-Acetylhexosaminidases; D002118:Calcium