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Basophils and mast cells are characteristic effector cells in allergic reactions. Sargahydorquinoic acid (SHQA), a compound isolated from Sargassum serratifolium (marine alga), possesses various biochemical properties, including potent antioxidant activities. The objective of the present study was to investigate inhibitory effects of SHQA on the activation of human basophilic KU812F cells induced by phorbol myristate acetate and A23187 (PMACI), a calcium ionophore. Furthermore, we confirmed the inhibitory effects of SHQA on the activation of rat basophilic leukemia (RBL)-2H3 cells induced by compound 48/80 (com 48/80), bone marrow-derived mast cells (BMCMCs) induced by anti-dinitrophenyl(DNP)-immunoglobulin E (IgE)/DNP-bovine serum albumin (BSA), DNP/IgE and on the reaction of passive cutaneous anaphylaxis (PCA) mediated by IgE. SHQA reduced PMACI-induced intracellular reactive oxygen species (ROS) and calcium levels. Western blot analysis revealed that SHQA downregulated the activation of ERK, p38, and NF-κB in a dose-dependent manner. Moreover, SHQA suppressed the production and gene expression of various cytokines, including interleukin (IL)-1 β, IL-4, IL-6, and IL-8 in PMACI-induced KU812F cells and IL-4 and tumor necrosis factor (TNF)- α in com 48/80-induced RBL-2H3 cells. It also determined the inhibition of PMACI, com 48/80- and IgE/DNP-induced degranulation by reducing the release of β -hexosaminidase. Furthermore, it attenuated the IgE/DNP-induced PCA reaction in the ears of BALB/c mice. These results suggest that SHQA isolated from S. serratifolium is a potential therapeutic functional food material for inhibiting effector cell activation in allergic reactions and anaphylaxis in animal model., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Mast cells are the primary cells that play a crucial role in the allergic diseases via secretion of diverse allergic mediators. Ursolic acid (UA) is a naturally occurring anti-inflammatory triterpenoid possessing various biological properties such as immune regulation, antioxidant, and anti-fibrotic. The aim of this study was to evaluate the effects of UA in FcεRI-mediated mast cell activation and allergic inflammation., Methods: In this study, mast cells were stimulated with immunoglobulin E (IgE) and the anti-allergic effects of UA were assessed by measuring the levels of allergic mediators. In vivo effects of UA were observed by generating passive cutaneous anaphylaxis (PCA) and active systemic anaphylaxis (ASA) in mouse model., Results: We found that UA inhibited the degranulation of mast cell by suppressing the intracellular calcium level in a concentration-dependent manner. UA inhibited the expression and the release of pro-inflammatory cytokines in mast cells. Anti-allergic effects of UA were demonstrated via suppression of FcεRI-mediated signaling molecules. In addition, UA inhibited the IgE-mediated PCA and ovalbumin-induced ASA reactions in a dose-dependent manner., Conclusions: Based on these findings, we suggest that UA might have potential as a therapeutic candidate for the treatment of allergic inflammatory diseases via inhibition of FcεRI-mediated mast cell activation., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The functional inhibition of mast cells, which serve as a key effector cells in allergic reactions may be a specific target for treating immunoglobulin (Ig)E-mediated allergic reactions, which occur in various allergic diseases including anaphylaxis, asthma, and atopic dermatitis. In this study, we demonstrated the effects of dabrafenib, a therapeutic agent used to treat metastatic melanoma, with a focus on mast cell activation and local cutaneous anaphylaxis. In two types of mast cells (RBL-2H3 and mouse bone marrow-derived mast cells), dabrafenib (0.01, 0.1, 1 μM) pretreatment significantly decreased IgE-induced degranulation, intracellular calcium influx, and the activity of intracellular signaling molecules, such as Lyn, Syk, Akt, and PLCγ. Dabrafenib ameliorated mRNA and protein expression levels of interleukin-4 and tumor necrosis factor-α by the reduction of nuclear localization of nuclear factor-κB and nuclear factor of activated T-cells. In passive cutaneous anaphylaxis, oral administration of dabrafenib (0.1, 1, 10 mg/kg) reduced local pigmentation and ear thickness in a dose-dependent manner. Taken together, these results suggest that dabrafenib is a therapeutic drug candidate that controls IgE-mediated allergic inflammatory diseases through suppression of mast cell activity., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Dioscoreae Rhizoma (MDR), the root of Dioscorea tokoro MAKINO, has been used for the treatment of arthritis, muscular pain and urinary diseases in oriental medicine. The present work evaluates a methanol extract of Dioscoreae Rhizoma (MDR). MDR did not show any cytotoxic effect on mouse lung fibroblast cells (mLFCs) or human fibroblast-like synovial cells (hFLSCs). However, it significantly reduced the proliferation of hFLSCs stimulated by interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha). MDR significantly inhibited the production of TNF-alpha and IL-1beta as well as down-regulating the expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in IL-1beta- and TNF-alpha-stimulated hFLSCs. MDR also effectively reduced the level of reactive oxygen species (ROS) in these cells. Taken together, these findings provide evidence that MDR may be a candidate for the treatment of rheumatoid arthritis (RA).