Spirodela polyrhiza extract modulates the activation of atopic dermatitis-related ion channels, Orai1 and TRPV3, and inhibits mast cell degranulation

Abstract

Context:Spirodela polyrhiza (L.) Schleid. (Lemnaceae), Spirodelae Herba (SH), has been known to relieve inflammation, urticaria and skin symptoms including pruritus, eczema and rash.Objective: The effects of SH extract on two calcium ion channels, Orai1 and TRPV3, and their potential as novel therapeutics for atopic dermatitis (AD) were investigated. The regulatory role of Orai1 on mast cell degranulation was evaluated.Materials and methods: The dried leaves of SH were extracted by 70% methanol. Effects of SH extract (100 μg/mL) in an HEK293T cell line overexpressing human Orai1 or TRPV3 were assessed. Ion channel modulation in transfected HEK293T cells was measured using a conventional whole-cell patch-clamp technique. IgE-antigen complex-stimulated mast cell degranulation was measured by β-hexosaminidase assay with morphological observation after treatment with 20, 50 and 100 μg/mL SH extract.Results: SH extract (100 μg/mL) significantly inhibited Orai1 activity (63.8 ± 0.97%) in Orai1-STIM1 co-overexpressed HEK293T cells. SH extract significantly increased TRPV3 activity (81.29 ± 0.05% at −100 mV) compared with the positive control 2-APB (100 μM), which induced full activation. SH extract inhibited degranulation in IgE-antigen complex-stimulated RBL-2H3 mast cells by decreasing β-hexosaminidase activity (3.14 ± 0.03, 2.56 ± 0.12 and 2.29 ± 0.08 mU/mg, respectively).Conclusion: Our results suggested that SH extract could treat abnormal skin barrier pathologies in AD through modulation of the activities of the calcium ion channels Orai1 and TRPV3 and inhibition of mast cell degranulation. This is the first report of an herbal effect on the modulation of ion channels associated with skin barrier disruption in AD pathogenesis.

Luteolin reduces fluid hypersecretion by inhibiting TMEM16A in interleukin-4 treated Calu-3 airway epithelial cells

“…SP extract is used to treat allergic inflammatory diseases, such as atopic dermatitis. Furthermore, SP extract inhibits mast cell degranulation and suppresses IL-4 and IL-13 expression, which is mediated by Th2 cells [21,22,25]. Our study clearly showed that SP EtOH and luteolin suppressed ANO1 activity, which is responsible for nasal hypersecretion in AR, in addition to alleviating electrolyte secretion via ANO1 inhibition in Calu-3 cells (Fig.…”

“…(SP) is widely used to relieve inflammation, urticaria, and symptoms of skin irritation, including pruritus, eczema, and rash [20,21]. According to a recent report, SP exerts a potential inhibitory effect on the calcium releaseactivated calcium channel, which is encoded by the ORAI1 gene and is responsible for Th2 activation and mast cell degranulation [22][23][24]. In addition, formulations containing SP or its ethanolic extract have been shown to alleviate allergic inflammation and pruritus in mice with atopic dermatitis [21,25].…”

Flos magnoliae constituent fargesin has an anti-allergic effect via ORAI1 channel inhibition

“…A 1290 Series high-performance liquid chromatograph (Agilent Technologies, Santa Clara, CA, USA) at The Korea Basic Science Institute, Seoul, Republic of Korea, was used to analyze the FM EtOH constituents as previously described [26]. After injecting 10 l of 5 mg/ml FM EtOH into a 3.0 × 100 mM, 2.7 M Poroshell 120 SB-C18 column (Agilent Technologies), the constituents were separated and identified at a 278 nM wavelength.…”

“…The -hexosaminidase activity was determined by colorimetric assay using p-nitrophenyl N-acetyl-D-glucosamine hydrolysis, as previously described [26,27]. RBL-2H3 mast cells were seeded in 48-well plates (2.5 × 10 5 cells/ml) and incubated for 24 h before sensitization with 1.0 mg/ml anti-dinitrophenyl (DNP)-IgE for 3 h followed by discarding the solution and washing the cells four times with PBS.…”

Modulatory Effect of Periostracum Cicadae and Betulae Cortex Extracts on the Activation of Atopic Dermatitis-Related Ion Channels Orai1 and Trpv3

“…To determine the effect of BC and PC on ORAI1 and TRPV3 activity, whole-cell patch clamping was used (Nam et al, 2016(Nam et al, , 2017. All experiments were performed at room temperature.…”