Imidacloprid inhibits IgE-mediated RBL-2H3 cell degranulation and passive cutaneous anaphylaxis

Abstract

BackgroundImidacloprid has been commonly used as a pesticide for crop protection and acts as nicotinic acetylcholine receptor agonists. Little information about the relationship between imidacloprid and allergy is available.ObjectiveThis study aims to examine the effects of imidacoprid on IgE-mediated mast cell activation.MethodsThe rat basophilic leukemia cell line RBL-2H3 (RBL-2H3 cells) were treated with 10-3 – 10-12 mol/L imidacloprid, followed by measuring the mediator production, influx of Ca2+ in IgE-activated RBL-2H3 cells, and the possible effects of imidacoprid on anti-dinitrophenyl IgE-induced passive cutaneous anaphylaxis (PCA).ResultsIt was shown that imidacoprid suppressed the production of histamine, β-hexosaminidase, leukotriene C4, interleukin-6, tumor necrosis factor-α, and Ca2+ mobilization in IgE-activated RBL-2H3 cells and decreased vascular extravasation in IgE-induced PCA.ConclusionIt is the first time to show that imidacloprid suppressed the activation of RBL-2H3 cells.

Phellinus linteusGrown on Germinated Brown Rice Inhibits IgE-Mediated Allergic Activity through the Suppression of FcεRI-Dependent Signaling PathwayIn VitroandIn Vivo

“…The increased intracellular calcium constitutes calcium-calmodulin complex that leads to the exocytosis of granules by inducing the SNARE complex activation [53, 74, 75]. Consistent with previously reported studies, we found that stimulation of IgE/Ag increases the levels of intracellular calcium in RBL-2H3 cells (Figure 4) [40, 41]. We observed that PBR-BuOH inhibited calcium influx assay compared with that in IgE/Ag-stimulated RBL-2H3 cells (Figure 4).…”

“…IgE-mediated degranulation requires increased calcium mobilization [40, 41]. To evaluate whether PBR-BuOH affects the calcium influx induced by IgE/antigen, RBL-2H3 cells were stained with calcium-sensitive dye Fluo-4.…”

“…Intracellular calcium levels were measured as previously described [30, 40, 41]. RBL-2H3 cells (2 × 10 4 cells/well) were sensitized with 200 ng/mL of DNP-specific IgE overnight and then pretreated with PBR-BuOH (25 and 50 μ g/mL) for 30 min.…”

Effect of clothianidin exposure at the no-observed-adverse-effect level (NOAEL) in a mouse model of atopic dermatitis

“…In addition, previous studies on plasma histamine have shown that imidacloprid, a class of NN, inhibits IgE-mediated degranulation in rat mast cell model cells (RBL-2H3), mouse bone marrow-derived mast cells, and human basophilic cells (KU812). This inhibition of degranulation has been associated with α7 nAChR [ 20 , 21 , 22 ]. Therefore, in the present study, CLO exposure may have inhibited mast cell degranulation via α7 nAChR, thereby suppressing histamine secretion and the induction of inflammation.…”