Calcium release-activated calcium modulator 1 as a therapeutic target in allergic skin diseases

Multiple Effects of Echinochrome A on Selected Ion Channels Implicated in Skin Physiology

Echinochrome A (Ech A), a naphthoquinoid pigment from sea urchins, is known to have anti-inflammatory and analgesic effects that have been suggested to be mediated by antioxidant activity and intracellular signaling modulation. In addition to these mechanisms, the ion channels in keratinocytes, immune cells, and nociceptive neurons may be the target for the pharmacological effects. Here, using the patch clamp technique, we investigated the effects of Ech A on the Ca²⁺-permeable TRPV3, TRPV1 and Orai1 channels and the two-pore domain K⁺ (K2P) channels (TREK/TRAAK, TASK-1, and TRESK) overexpressed in HEK 293 cells. Ech A inhibited both the TRPV3 and Orai1 currents, with IC₅₀ levels of 2.1 and 2.4 μM, respectively. The capsaicin-activated TRPV1 current was slightly augmented by Ech A. Ech A alone did not change the amplitude of the TREK-2 current (I_TREK2), but pretreatments with Ech A markedly facilitated I_TREK2 activation by 2-APB, arachidonic acid (AA), and acidic extracellular pH (pH_e). Similar facilitation effects of Ech A on TREK-1 and TRAAK were observed when they were stimulated with 2-APB and AA, respectively. On the contrary, Ech A did not affect the TRESK and TASK-1 currents. Interestingly, the I_TREK2 maximally activated by the combined application of 2-APB and Ech A was not inhibited by norfluoxetine but was still completely inhibited by ruthenium red. The selective loss of sensitivity to norfluoxetine suggested an altered molecular conformation of TREK-2 by Ech A. We conclude that the Ech A-induced inhibition of the Ca²⁺-permeable cation channels and the facilitation of the TREK/TRAAK K2P channels may underlie the analgesic and anti-inflammatory effects of Ech A.

The role of genetic factors in familial case of acne

Acne is one of the most common dermatoses. A prominent genetic component for this disease has been reported and the manifestation in first-line relatives is considered an important risk factor. Here we present a clinical case illustrating the relevance of particular genetic polymorphisms mapped to NCF1, CD3E, ORAI1, IGHM and TAZ in patients with severe forms and burdened family history of the disease. Genetic examination identified the same allelic variants in five candidate target genes (NCF1, CD3E, ORAI1, IGHM and TAZ) in two closely related patients (father and son) with severe acne. The identified genetic configuration may interfere with the oxidase activity and promote defects in mitochondrial function along with reduced T cell proliferation and imbalanced immunoglobulin production. The findings may provide an important reference point for further clinical investigation and treatment of severe torpid dermatoses.

Genetic polymorphisms of FCGR2A, ORAI1 and CD40 are associated with risk of lung cancer

FCGR2A, ORAI1 and CD40 are all involved in the immune and inflammatory responses in the human body, whereas its association with lung cancer is still unclear. This study aimed to investigate the effects of polymorphisms in these genes on the susceptibility to lung cancer. Six candidate single nucleotide polymorphisms (SNPs) were genotyped using a MassARRAY platform in a discovery cohort, including 400 lung cancer patients and 400 healthy controls, and validated in a replication cohort, including 529 lung cancer cases and 532 controls. Comparing the allele frequency distributions, we found that the rs1801274-G, rs511278-T and rs1883832-T were risk alleles for lung cancer (P < 0.05), whereas the minor allele of rs12320939-T was a protective allele for the disease (P = 0.037). Comparing the genotype frequency distributions, we found that rs1801274-GG, rs511278-CT and of rs1883832-TT were risk genotype for lung cancer (P < 0.05). Genetic model analysis showed that the rs1801274 A>G was correlated with an elevated risk of lung cancer in recessive and log-additive models (P < 0.05); rs511278 C>T exhibited an increased risk of disease in dominant and log-additive models (P < 0.05); rs1883832 C>T had a strong relationship with risk of disease in all three models (P < 0.001), whereas rs12320939 G>T was correlated to a reduced risk of disease in recessive and log-additive models (P < 0.05). Finally, the association between the above SNPs and lung cancer risk was validated in a replication cohort (P < 0.05). These results shed new light on the association between immune-related genes and risk of lung cancer, and might be useful for the identification of high-risk individuals.

Targeted Therapy for Chronıc Spontaneous Urtıcarıa: Ratıonale and Recent Progress

Chronic spontaneous urticaria (CSU) is characterized by the presence of wheals, angioedema, or both for at least 6 weeks. It may persist for a long time-up to 50% of the patients have been reported to be symptomatic 5 years after the onset. Some patients can suffer more than one episode of CSU during their lifetime. Considering the recurrences, disabling symptoms, and significant impact on quality of life, proper and effective treatment of CSU is critical. The use of antihistamines (AHs) is still the mainstay of treatment. However, given the low rates of response to AHs (38.6% and 63.2% to standard doses and higher doses, respectively), the complete control of symptoms seems difficult to attain. The use of omalizumab for CSU has been a major breakthrough in the care of patients with CSU. However, the partial response and lack of response to omalizumab in a subgroup of patients, as high as 70% in some studies, make the development of alternative treatments desirable. Ever-increasing knowledge on the pathogenesis is making new target molecules available and enabling drug development for CSU. In addition to drug repurposing as in anti-IL-4/13, IL-5, and IL-17 antibodies, novel targeted therapy options such as ligelizumab and Bruton's tyrosine kinase inhibitors are currently undergoing clinical trials and will be available in the near future. This article reviews the current challenges in the treatment of CSU, the pathogenesis and potential target molecules, and the rationale for novel treatments and their rapidly developing status.

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

Flos magnoliae (FM), the dry flower buds of Magnolia officinalis or its related species, is a traditional herbal medicine commonly used in Asia for symptomatic relief of and treating allergic rhinitis, headache, and sinusitis. Although several studies have reported the effects of FM on store-operated calcium entry (SOCE) via the ORAI1 channel, which is essential during intracellular calcium signaling cascade generation for T cell activation and mast cell degranulation, the effects of its isolated constituents on SOCE remain unidentified. Therefore, we investigated which of the five major constituents of 30% ethanoic FM (vanillic acid, tiliroside, eudesmin, magnolin, and fargesin) inhibit SOCE and their physiological effects on immune cells. The conventional whole-cell patch clamp results showed that fargesin, magnolin, and eudesmin significantly inhibited SOCE and thus human primary CD4⁺ T lymphocyte proliferation, as well as allergen-induced histamine release in mast cells. Among them, fargesin demonstrated the most potent inhibitory effects not only on ORAI1 (IC50 = 12.46 ± 1.300 μM) but also on T-cell proliferation (by 87.74% ± 1.835%) and mast cell degranulation (by 20.11% ± 5.366%) at 100 μM. Our findings suggest that fargesin can be a promising candidate for the development of therapeutic drugs to treat allergic diseases.

A highly selective and sensitive fluorescence probe for a specific binding site on insect ryanodine receptors

There is a significant need to study the binding of active compounds to the specific sites on insect ryanodine receptors (RyRs) that are the targets of two novel classes of diamide insecticides to which insects are becoming increasingly resistant. Here, we describe a rapid assay to study the action of potential compounds on the flubendiamide (Flu) binding site of insect RyRs that uses a fluorescence polarization assay with the fluorescence probe Flu-R-L that we synthesized. The IC₅₀ of Flu for inhibiting probe binding on insect RyR was 18.82 ng/mL. The binding of 86 novel phthalic diamide derivatives on insect RyRs was studied using this newly established assay, and the compounds that exhibited high-affinity binding in the assay also possessed in vivo insecticidal activity against Plutella xylostella. Thus, Flu-R-L is a highly selective and sensitive fluorescence probe for studying the binding affinity of novel compounds to the Flu binding site of insect RyRs. The assay based on Flu-R-L is a rapid, accurate, and sensitive method for the screening of potentially bioactive molecules that bind specifically to insect RyRs.