Inhibitory effects of an ellagic acid glucoside, okicamelliaside, on antigen-mediated degranulation in rat basophilic leukemia RBL-2H3 cells and passive cutaneous anaphylaxis reaction in mice

Ellagic acid reduces murine schistosomiasis mansoni immunopathology via up-regulation of IL-10 and down-modulation of pro-inflammatory cytokines production

“…Furthermore, EA treatment led to reduce level of IL-6 and increase level of IL-10 in bronchoalveolar lavage fluid of acute lung injury murine model 54 . EA glucoside inhibited expression of IL-4 and IL-13 in rat basophilic leukemia cells 55 . In addition, pomegranate juice containing EA inhibited the synthesis of IL-17, IL-6 and TNF-a from PBMC; and stimulated the production of IL-2 and G-CSF 56 .…”

Use of a rat basophil leukemia (RBL) cell-based immunological assay for allergen identification, clinical diagnosis of allergy, and identification of anti-allergy agents for use in immunotherapy

“…In RBL-2H3 cells, polyphenolic compounds from grapeseed extract blocked IgE-induced degranulation partly through the suppression on F ce RI expression and decreased Ca 2+ uptake (Chen et al, 2012). Suppression of the phosphorylation of Syk and PLC 1 in the principle signaling pathway might be involved in the attenuated degranulation of these cells by okicamelliaside from Camellia japonica leaves (Kuba-Miyara et al, 2012). Flavonoids from Citrus unshiu inhibited RBL-2H3 cell degranulation, in part, via a suppression of PI3K activity in the complementary signaling pathway (Kobayashi & Tanabe, 2006).…”

“…In recent studies, it was reported that various dietary natural products can inhibit degranulation via suppression of signaling pathways, suggesting their potential use in allergy therapy (Chen et al, 2012;Chung et al, 2013;Han et al, 2011;Ishida et al, 2013;Kobayashi & Tanabe, 2006;Kuba-Miyara et al, 2012;Zhang et al, 2012). In allergic reactions, signal transduction is triggered by the allergen cross-linking mast-cell surface allergenspecific IgE-bound high-affinity receptors (F ce RI).…”

“…After the phosphorylation cascade, release of Ca 2+ from intracellular stores, followed by extracellular Ca 2+ influx, occurs. These events lead eventually to conformational changes in the cytoskeleton that in turn induce degranulation and release of mediators like histamine, -hexosaminidase, and pro-inflammatory cytokines like interleukin (IL)-4 and tumor necrosis factor (TNF)- (Gilfillan & Tkaczyk, 2006;Kuba-Miyara et al, 2012).…”

Synthesis of Okicamelliaside, a Glucoside of Ellagic Acid with Potent Anti-Degranulation Activity

“…1) Since it possessed anti-degranulation activity 12,000 times greater than that of ketotifen fumarate, 1,2) okicamelliaside can be expected to be an anti-allergic agent able to be produced in large quantity by chemical synthesis. Okicamelliaside has a tethered catechol structure that is unique among related -D-glucosides (2a-c) 3,4) of ellagic acid.…”