Diospyros kaki calyx inhibits immediate-type hypersensitivity via the reduction of mast cell activation

Abstract

Context:Diospyros kaki L. (Ebenaceae) fruit is widely distributed in Asia and is known to exert anti-inflammatory and antithrombotic effects.Objective: We evaluated the inhibitory effect of aqueous extract of D. kaki calyx (AEDKC) on mast cell-mediated immediate-type hypersensitivity and underlying mechanism of action.Materials and methods: For in vivo, ovalbumin (OVA)-induced active systemic anaphylaxis (ASA) and immunoglobulin (Ig) E-mediated passive cutaneous anaphylaxis (PCA) models were used. In the ASA, AEDKC (1–100 mg/kg) was orally administered 3 times during 14 days. In the PCA, AEDKC was orally treated 1 h before the antigen challenge. The control drug dexamethasone was used to compare the effectiveness of AEDKC. For in vitro, IgE-stimulated RBL-2H3 cells and primary cultured peritoneal mast cells were used to determine the role of AEDKC (0.01–1 mg/mL).Results: Oral administration of AEDKC dose dependently suppressed rectal temperature decrease and increases in serum histamine, total IgE, OVA-specific IgE, and interleukin (IL)-4 in the ASA. In the PCA, AEDKC reduced Evans blue pigmentation. Compared to dexamethasone (10 mg/kg), AEDKC (100 mg/kg) showed similar inhibitory effects in vivo. AEDKC concentration dependently suppressed the release of histamine and β-hexosaminidase through the reduction of intracellular calcium in mast cells. In addition, AEDKC decreased the expression and secretion of tumour necrosis factor-α and IL-4 by the reduction of nuclear factor-κB. The inhibitory potential of AEDKC (1 mg/mL) was similar with dexamethasone (10 μM) in vitro.Conclusions: We suggest that AEDKC may be a potential candidate for the treatment of mast cell-mediated allergic diseases.

Raf kinase inhibitor protein negatively regulates FcεRI-mediated mast cell activation and allergic response

“…Suppresses the Activation of PI3K on IgE−FceRI Stimulation. PI3K consists of the p85 regulatory subunit and the p110 catalytic subunit, and both are involved in mast cell activation signaling (23). During FceRI-mediated mast cell activation, the adapter protein Gab2 binds to the PI3K p85 regulatory subunit and recruits it to the cell membrane, resulting in activation of p85 by Fyn or Syk (5).…”

“…All PI3K p85 isoforms have an N-terminal Src homology 3 (SH3) domain; two Prorich regions near the N terminus; a BCR homology domain, which binds to phosphorylated tyrosine; and a PI3K p110 binding domain located between two Src homology 2 domains, which form the PI3K p85 core domain (SI Appendix, Fig. S5C) (23). Domain-mapping experiments showed that RKIP interacted with p85 in a manner dependent on the domain of the p85 core (aa 332 to 724) but not on the SH3 domain and P-BH-P domain (aa 1 to 331) (SI Appendix, Fig.…”

The Anti-inflammatory and Immune-Boosting Potential of Quercetin-3-O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranoside in LPS–Stimulated RAW264.7 Macrophages

“…Reports have shown that the plant has anti-allergic and attenuation effects in atopic dermatitis-like skin lesions. The D. kaki plant extract effectively inhibits the mast cell activation by reducing the expression of a chemokine and proinflammatory cytokines through the modulation of NF-κB signaling pathway (Kim et al 2017;Yu et al 2017). In our previous studies, we demonstrated the anti-inflammatory and anti-melanogenesis effects of quercetin (QC) and its modified form quercetin 3-O-β-D-(2"-O-galloyl)-glucopyranoside (Q32G) isolated from D. kaki (Jung et al 2015;Cho et al 2016).…”

Unveiling major ethnopharmacological aspects of genus Diospyros in context to its chemical diversity: A comprehensive overview

“…Regarding the anthelmintic activity, (Sadun & Vajrasthira, 1954) factor-κB. The results suggested that the extract might be a potential candidate for the management of mast cell-mediated allergic conditions (Kim, Park, et al, 2017).…”