Challenges in the Therapeutic Targeting of KCa Channels: From Basic Physiology to Clinical Applications.

Calcium-activated potassium (KCa) channels are ubiquitously expressed throughout the body and are able to regulate membrane potential and intracellular calcium concentrations, thereby playing key roles in cellular physiology and signal transmission. Consequently, it is unsurprising that KCa channels have been implicated in various diseases, making them potential targets for pharmaceutical interventions. Over the past two decades, numerous studies have been conducted to develop KCa channel-targeting drugs, including those for disorders of the central and peripheral nervous, cardiovascular, and urinary systems and for cancer. In this review, we synthesize recent findings regarding the structure and activating mechanisms of KCa channels. We also discuss the role of KCa channel modulators in therapeutic medicine. Finally, we identify the major reasons behind the delay in bringing these modulators to the pharmaceutical market and propose new strategies to promote their application.

Inhibition of Ca2+-permeable TRPV3 and inflammatory cytokine release by honokiol and magnolol in human epidermal keratinocytes.

Transient receptor potential vanilloid-3 (TRPV3) ion channels are prominently expressed in keratinocytes, playing a vital role in skin functions. Honokiol and magnolol (H&M) the primary bioactive constituents in Magnolia officinalis extract, demonstrate anti-inflammatory and skin-protective properties. Nevertheless, the underlying mechanism regarding their effect on Ca2+-permeable ion channels remain unclear. Our purpose in this study is to investigate the effect of H&M on TRPV3 and cytokine release in normal human epidermal keratinocytes (NHEKs), including its gain-of-function (GOF) mutants (G573S and G573C) associated with Olmstead syndrome. We performed whole-cell patch-clamp, fura-2 spectrofluorimetry to investigate channels activity, CCK-8 assay to analyze cell death and enzyme-linked immunosorbent assay to assess the cytokine release from NHEKs. H&M inhibited the TRPV3 current (ITRPV3) and cytosolic calcium increase in NHEKs, HEK293T cells overexpressing hTRPV3 and its GOF mutants. Moreover, the release of pro-inflammatory cytokines (interleukin-6 and -8) from keratinocytes stimulated by TRPV3 agonist was effectively suppressed by H&M. Our findings provide insights into the mechanism underlying the anti-inflammatory effects of H&M, highlighting their potential in treating skin diseases.

Anti-Inflammatory Effects of Alphitolic Acid Isolated from Agrimonia coreana Nakai Extracts Are Mediated via the Inhibition of ICRAC Activity in T Cells.

Agrimonia pilosa Ledeb., an important medicinal herb in traditional East Asian medicine, is primarily used to treat abdominal pain, dysentery, and hemostasis. There are ten other reported species of Agrimonia plants, including Agrimonia coreana Nakai-a naturally growing species in South Korea-and Agrimonia eupatoria Linn. Although recent studies have isolated numerous active constituents and investigated their effects, the medicinal utility of this herb is not yet fully explored. Through patch-clamp recording, a previous study reported that Agrimonia plant extracts inhibit the function of Ca2+ release-activated Ca2+ channels (CRACs). Herein, we aimed to identify and isolate the main compounds in A. coreana responsible for CRAC inhibition while assessing the anti-inflammatory effects mediated by this inhibition. We demonstrated for the first time that alphitolic acid isolated from A. coreana has a dose-dependent inhibitory effect on CRAC activity and, thus, an inhibitory effect on intracellular calcium increase. Furthermore, analysis of human CD4+ T cell proliferation via the carboxyfluorescein diacetate succinimidyl ester method revealed that alphitolic acid inhibited T cell proliferation in a concentration-dependent manner. Our findings provide a theoretical basis for the potential therapeutic use of alphitolic acid in the treatment of inflammatory diseases.

Alpha-Mangostin: A Potent Inhibitor of TRPV3 and Pro-Inflammatory Cytokine Secretion in Keratinocytes.

The TRPV3 calcium ion channel is vital for maintaining skin health and has been associated with various skin-related disorders. Since TRPV3 is involved in the development of skin inflammation, inhibiting TRPV3 could be a potential treatment strategy. Alpha-mangostin isolated from Garcinia mangostana L. extract exhibits diverse positive effects on skin health; however, the underlying mechanisms remain obscure. This study investigated the TRPV3-inhibitory properties of alpha-mangostin on TRPV3 hyperactive mutants associated with Olmsted syndrome and its impact on TRPV3-induced cytokine secretion and cell death. Our findings demonstrate that alpha-mangostin effectively inhibits TRPV3, with an IC50 of 0.077 ± 0.013 µM, showing inhibitory effects on both wild-type and mutant TRPV3. TRPV3 inhibition with alpha-mangostin decreased calcium influx and cytokine release, protecting cells from TRPV3-induced death. These results indicate that alpha-mangostin reduced inflammation in TRPV3-activated skin keratinocytes, suggesting that alpha-mangostin could be potentially used for improving inflammatory skin conditions such as dermatitis.

Overlooked KCNQ4 variants augment the risk of hearing loss.

Pathogenic variants of KCNQ4 cause symmetrical, late-onset, progressive, high-frequency-affected hearing loss, which eventually involves all frequencies with age. To understand the contribution of KCNQ4 variants to hearing loss, we analyzed whole-exome and genome sequencing data from patients with hearing loss and individuals whose hearing phenotypes were unknown. In KCNQ4, we identified seven missense variants and one deletion variant in 9 hearing loss patients and 14 missense variants in the Korean population with an unknown hearing loss phenotype. The p.R420W and p.R447W variants were found in both cohorts. To investigate the effects of these variants on KCNQ4 function, we performed whole-cell patch clamping and examined their expression levels. Except for p.G435Afs*61, all KCNQ4 variants exhibited normal expression patterns similar to those of wild-type KCNQ4. The p.R331Q, p.R331W, p.G435Afs*61, and p.S691G variants, which were identified in patients with hearing loss, showed a potassium (K+) current density lower than or similar to that of p.L47P, a previously reported pathogenic variant. The p.S185W and p.R216H variants shifted the activation voltage to hyperpolarized voltages. The channel activity of the p.S185W, p.R216H, p.V672M, and p.S691G KCNQ4 proteins was rescued by the KCNQ activators retigabine or zinc pyrithione, whereas p.G435Afs*61 KCNQ4 proteins were partially rescued by sodium butyrate, a chemical chaperone. Additionally, the structure of the variants predicted using AlphaFold2 showed impaired pore configurations, as did the patch-clamp data. Our findings suggest that KCNQ4 variants may be overlooked in hearing loss that starts in adulthood. Some of these variants are medically treatable; hence, genetic screening for KCNQ4 is important.

Multi-target modulation of ion channels underlying the analgesic effects of α-mangostin in dorsal root ganglion neurons.

BACKGROUND: α-Mangostin is a xanthone isolated from the pericarps of mangosteen fruit with, and has analgesic properties. Although the effects suggest an interaction of α-mangostin with ion channels in the nociceptive neurons, electrophysiological investigation of the underlying mechanism has not been performed. HYPOTHESIS: We hypothesized that α-Mangostin exerts its analgesic effects by modulating the activity of various ion channels in dorsal root ganglion (DRG) neurons. METHODS: We performed a whole-cell patch clamp study using mouse DRG neurons, HEK293T cells overexpressing targeted ion channels, and ND7/23 cells. Molecular docking (MD) and in silico absorption, distribution, metabolism, and excretion (ADME) analyses were conducted to obtain further insights into the binding sites and pharmacokinetics, respectively. RESULTS: Application of α-mangostin (1-3 µM) hyperpolarized the resting membrane potential (RMP) of small-sized DRG neurons by increasing background K+ conductance and thereby inhibited action potential generation. At micromolar levels, α-mangostin activates TREK-1, TREK-2, or TRAAK, members of the two-pore domain K+ channel (K2P) family known to be involved in RMP formation in DRG neurons. Furthermore, capsaicin-induced TRPV1 currents were potently inhibited by α-mangostin (0.43 ± 0.27 µM), and partly suppressed tetrodotoxin-sensitive voltage-gated Na+ channel (NaV) currents. MD simulation revealed that multiple oxygen atoms in α-mangostin may form stable hydrogen bonds with TREKs, TRAAK, TRPV1, and NaV channels. In silico ADME tests suggested that α-mangostin may satisfy the drug-likeness properties without penetrating the blood-brain barrier. CONCLUSION: The analgesic properties of α-mangostin might be mediated by the multi-target modulation of ion channels, including TREK/TRAAK activation, TRPV1 inhibition, and reduction of the tetrodotoxin-sensitive NaV current. The findings suggest that the phytochemical can be a multi-ion channel-targeting drug and an alternative drug for effective pain management.

The traditional herbal medicines mixture, Banhasasim-tang, relieves the symptoms of irritable bowel syndrome via modulation of TRPA1, NaV1.5 and NaV1.7 channels.

ETHNOPHARMACOLOGICAL RELEVANCE: The cause of irritable bowel syndrome (IBS), a functional gastrointestinal (GI) disorder, remains unclear. Banhasasim-tang (BHSST), a traditional herbal medicines mixture, mainly used to treat GI-related diseases, may have a potential in IBS treatment. IBS is characterized by abdominal pain as the main clinical symptom, which seriously affects the quality of life. AIM OF THE STUDY: We conducted a study to evaluate the effectiveness of BHSST and its mechanisms of action in treating IBS. MATERIALS AND METHODS: We evaluated the efficacy of BHSST in a zymosan-induced diarrhea-predominant animal model of IBS. Electrophysiological methods were used to confirm modulation of transient receptor potential (TRP) and voltage-gated Na+ (NaV) ion channels, which are associated mechanisms of action. RESULTS: Oral administration of BHSST decreased colon length, increased stool scores, and increased colon weight. Weight loss was also minimized without affecting food intake. In mice administered with BHSST, the mucosal thickness was suppressed, making it similar to that of normal mice, and the degree of tumor necrosis factor-α was severely reduced. These effects were similar to those of the anti-inflammatory drug-sulfasalazine-and antidepressant-amitriptyline. Moreover, pain-related behaviors were substantially reduced. Additionally, BHSST inhibited TRPA1, NaV1.5, and NaV1.7 ion channels associated with IBS-mediated visceral hypersensitivity. CONCLUSIONS: In summary, the findings suggest that BHSST has potential beneficial effects on IBS and diarrhea through the modulation of ion channels.

Laparo-endoscopic single-site versus conventional laparoscopic surgery for early-stage endometrial cancer: A randomized controlled non-inferiority trial.

OBJECTIVE: To evaluate the feasibility and safety of laparo-endoscopic single-site surgery (LESS) compared with conventional laparoscopic surgery (CLS) for early-stage endometrial cancer. METHODS: Patients with clinical stage IA, IB, grade 1-3 endometrial cancer were randomly assigned to undergo LESS or CLS. The primary endpoint was the non-inferiority of LESS to CLS in terms of operation time and the number of resected pelvic lymph nodes. We set the non-inferior margin of the operation time as within 15% (24 min) and the number of resected pelvic lymph nodes as within 20% (5.2 lymph nodes). RESULTS: There was no significant difference between the LESS group (n = 53) and the CLS group (n = 54) in terms of age, weight, body mass index, parity, menopausal status, history of abdominal surgery, and preoperative CA-125 levels. The total operation time was comparable between the two groups. On average, 4.6 fewer pelvic lymph nodes were retrieved in the LESS group, which was within the non-inferiority margin. There were no significant differences in the incidence of intra- and postoperative complications, estimated blood loss, and postoperative hospital stay between the two groups. After a median follow-up time of 34 months (range, 2-242), the progression-free survival rates were 96.2% and 98.1% (P = 0.55) in the LESS group and the CLS group, and the overall survival rates were 98.1% and 100.0% (P = 0.31), respectively. CONCLUSION: LESS surgical staging was non-inferior to CLS and had acceptable feasibility, safety, and efficacy for the surgical management of early-stage endometrial cancer. TRIAL REGISTRATION: Clinicaltrial.gov identifier number: NCT01679522.

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 (ITREK2), but pretreatments with Ech A markedly facilitated ITREK2 activation by 2-APB, arachidonic acid (AA), and acidic extracellular pH (pHe). 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 ITREK2 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.

Inhibition of ANO1 by Cis- and Trans-Resveratrol and Their Anticancer Activity in Human Prostate Cancer PC-3 Cells.

Anoctamin1 (ANO1), a calcium-activated chloride channel, is involved in the proliferation, migration, and invasion of various cancer cells including head and neck squamous cell carcinoma, lung cancer, and prostate cancer. Inhibition of ANO1 activity or downregulation of ANO1 expression in these cancer cells is known to exhibit anticancer effects. Resveratrol, a natural polyphenol abundant in wines, grapes, berries, soybeans, and peanuts, shows a wide variety of biological effects including anti-inflammatory, antioxidant, and anticancer activities. In this study, we investigated the effects of two stereoisomers of resveratrol on ANO1 activity and found that cis- and trans-resveratrol inhibited ANO1 activity with different potencies. Cis- and trans-resveratrol inhibited ANO1 channel activity with IC50 values of 10.6 and 102 µM, respectively, and had no significant effect on intracellular calcium signaling at 10 and 100 µM, respectively. In addition, cis-resveratrol downregulated mRNA and protein expression levels of ANO1 more potently than trans-resveratrol in PC-3 prostate cancer cells. Cis- and trans-resveratrol significantly reduced cell proliferation and cell migration in an ANO1-dependent manner, and both resveratrol isomers strongly increased caspase-3 activity, PARP cleavage, and apoptotic sub-G1 phase ratio in PC-3 cells. These results revealed that cis-resveratrol is a potent inhibitor of ANO1 and exhibits ANO1-dependent anticancer activity against human metastatic prostate cancer PC-3 cells.

A phase II evaluation of temsirolimus with carboplatin and paclitaxel followed by temsirolimus consolidation in clear cell ovarian cancer: An NRG oncology trial.

OBJECTIVE: The primary objective of the study was to estimate the 12-month progression-free survival (PFS) for carboplatin/paclitaxel + temsirolimus in women with newly diagnosed clear cell ovarian cancer (CCOC), compared to historical controls in this patient population. METHODS: Patients with Stage III or IV CCOC were treated with Paclitaxel 175 mg/m2 on Day 1, Carboplatin AUC 6 Day 1, and temsirolimus (CCI-779) 25 mg IV Days 1 and 8 every 3 weeks for Cycles 1-6 or disease progression, followed by consolidation therapy with temsirolimus 25 mg Days 1, 8, and 15 every 3 weeks cycles 7-17 or until disease progression. RESULTS: Ninety patients were accrued to the study: 45 in the US and Korea (US/Korea) and 45 in Japan. Twenty-two percent received ≤6 cycles of therapy while 28% completed all 17 cycles of chemotherapy. Median PFS (OS) was 11 (23) months for US/Korea and 12 (26) months for Japan. In the US, none of suboptimally debulked patients had PFS >12 months, and 49% of optimal patients did, compared to 25% and 59% in Japan. Most common grade 3-4 adverse events were neutropenia, leukopenia, anemia, thrombocytopenia, hypertension, hypertriglyceridemia, and oral mucositis. CONCLUSION: The carboplatin/paclitaxel + temsirolimus regimen was well tolerated. In optimally debulked patients, 54% had a PFS >12 months. This regimen did not statistically significantly increase PFS at 12 months compared to historical controls. No statistically significant differences in PFS or OS were observed between US/Korea vs Japan, or Asians vs non-Asians.

NADPH Oxidase 1 Mediates Acute Blood Pressure Response to Angiotensin II by Contributing to Calcium Influx in Vascular Smooth Muscle Cells.

BACKGROUND: Reactive oxygen species (ROS) and calcium ions (Ca2+) are among the major effectors of Ang II (angiotensin II) in vascular smooth muscle cells. ROS are related to Ca2+ signaling or contraction induced by Ang II, but little is known about their detailed functions. Here, NOX (NADPH oxidase), a major ROS source responsive to Ang II, was investigated regarding its contribution to Ca2+ signaling. METHODS: Vascular smooth muscle cells were primary cultured from rat aorta. Ca2+ and ROS were monitored mainly using fura-2 and HyPer family probes' respectively. Signals activating NOX were examined with relevant pharmacological inhibitors and genetic manipulation techniques. RESULTS: Ang II-induced ROS generation was found to be biphasic: the first phase of ROS production, which was mainly mediated by NOX1, was small and transient, preceding a rise in Ca2+, and the second phase of ROS generation, mediated by NOX1 and NOX4, was slow but sizeable, continuing over tens of minutes. NOX1-derived superoxide in the first phase is required for Ca2+ influx through nonselective cation channels. AT1R (Ang II type 1 receptor)-Gßγ-PI3Kγ (phosphoinositide 3-kinase γ) signaling pathway was responsible for the rapid activation of NOX1 in the first phase, while in the second phase, NOX1 was further activated by a separate AT1R-Gαq/11-PLC (phospholipase C)-PKCß (protein kinase C ß) signaling axis. Consistent with these observations, aortas from NOX1-knockout mice exhibited reduced contractility in response to Ang II, and thus the acute pressor response to Ang II was also attenuated in NOX1-knockout mice. CONCLUSIONS: NOX1 mediates Ca2+ signal generation and thereby contributes to vascular contraction and blood pressure elevation by Ang II.

In-vitro and in-vivo anti-allergic effects of magnolol on allergic rhinitis via inhibition of ORAI1 and ANO1 channels.

ETHNOPHARMACOLOGICAL RELEVANCE: Flos Magnoliae (the dried flower buds of Magnolia biondii Pamp, FM) is a known herbal traditional medicine used for the symptomatic relief of nasal congestion and rhinorrhea caused by rhinitis and sinusitis. Magnolol, a neolignan from the magnolia family, is a secondary metabolite known to have anti-allergic and anti-inflammatory effects. However, the underlying mechanisms and therapeutic effect of magnolol in the treatment of allergic rhinitis (AR) remain elusive. AIMS OF THE STUDY: Anoctamin 1 (ANO1), a calcium-activated anion channel, mediates mucus and electrolyte secretion in nasal airway epithelial cells, whereas calcium release-activated calcium channel protein 1 (ORAI1) participates in the activation of T-lymphocytes and mast cells. The aim of our study is to understand the mechanisms of action of magnolol against AR, i.e., whether it acts through the modulation of ANO1 and ORAI1 channels that are expressed in nasal epithelial cells and T-lymphocytes, respectively. MATERIALS AND METHODS: Whole-cell patch clamp was used to record the activity of ORAI1 and ANO1 ion channels in ORAI1 or ANO1 overexpressed HEK293T cells, while the Ussing chamber apparatus was used to measure electrolyte transport via the epithelium, in Calu-3 cells cultured in an air-liquid interface. Additionally, calcium imaging of Jurkat T-lymphocytes was used to assess changes in the intracellular calcium concentration. Magnolol toxicity was assessed using the CCK-8 assay, and its effect on T-lymphocyte proliferation was measured by labeling human primary T-lymphocytes with carboxyfluorescein succinimidyl ester. Finally, OVA-induced Balb/c mice were employed to evaluate the effect of magnolol on nasal symptoms, as well as cytokine and eosinophil infiltration in AR. RESULTS: Magnolol inhibits ORAI1 and ANO1 channels in a concentration-dependent manner. Magnolol (30 µM) inhibits anti-CD3 induced cellular proliferation and production of IL-2 via ORAI1 channels in T-lymphocytes. Further, ATP-induced electrolyte transport mediated by ANO1 channels is significantly inhibited by magnolol in IL-4 sensitized Calu-3 cells. Notably, 300 µM magnolol significantly attenuates cytokine and eosinophil infiltration, thus alleviating AR symptoms in mice OVA-induced AR. CONCLUSION: Magnolol may be a promising therapeutic agent for the treatment and prevention of AR.

A serial multiple mediator model of sense of coherence, coping strategies, depression, and quality of life among gynecologic cancer patients undergoing chemotherapy.

PURPOSE: This study evaluated whether coping strategies (positive reframing, planning, and active coping) and depression mediate the relationship between sense of coherence (SOC) and quality of life (QoL) using a serial multiple mediator model in patients with gynecologic cancer who are undergoing chemotherapy. METHODS: A sample of 148 participants, with a mean age of 52.17 years (range 20-75) and diagnosed with gynecological cancer (e.g., cervix, ovary and endometrium) was surveyed in a cross-sectional study. Data were collected using a structured self-reporting questionnaire. A serial multiple mediator model was analyzed to explain sequential causality among two mediators (coping strategy and depression) and to investigate the direct and indirect effects of the mediator model in SPSSWIN 26.0 and PROCESS macro program. RESULTS: The conceptual serial mediation model of SOC, positive reframing, depression, and QoL revealed a significant positive total effect (coefficient c = 13.099, SE = 1.647, p < 0.001). The path through single mediation of positive reframing (Effect = 0.925) and depression (Effect = 5.942) and that through both mediators (Effect = 1.161) were statistically significant. The total indirect effect was also statistically significant (Effect = 8.028). Moreover, the conceptual serial mediation model on SOC, planning, depression, and QoL revealed a significant positive total effect (coefficient c = 13.099, SE = 1.647, p < 0.001). The path through both mediation of planning and depression (Effect = 1.162) and the total indirect effect were statistically significant (Effect = 8.172). CONCLUSIONS: Helping patients with gynecologic cancer undergoing chemotherapy to strengthen SOC may improve QoL by equipping them with efficient positive reframing or planning strategies to reduce depression.

Definitive Chemoradiotherapy versus Radical Hysterectomy Followed by Tailored Adjuvant Therapy in Women with Early-Stage Cervical Cancer Presenting with Pelvic Lymph Node Metastasis on Pretreatment Evaluation: A Propensity Score Matching Analysis.

To compare the oncologic outcomes between chemoradiotherapy (CRT) and radical hysterectomy followed by tailored adjuvant therapy in patients with early cervical cancer presenting with pelvic lymph node metastasis. We retrospectively analyzed the medical records of women with early cervical cancer presenting with positive pelvic nodes identified on pretreatment imaging assessment. Propensity score matching was employed to control for the heterogeneity between two groups according to confounding factors. Overall survival, disease-free survival, and pattern of failure were compared between the two groups. A total of 262 patients were identified; among them, 67 received definitive CRT (group A), and 195 received hysterectomy (group B). Adjuvant therapy was administered to 88.7% of group B. There were no significant differences between group A and group B regarding the 5-year overall survival rates (89.2% vs. 89.0%) as well as disease-free survival rates (80.6% vs. 82.7%), and patterns of failure. Distant metastasis was the major failure pattern identified in both groups. In multivariate analysis, non-squamous histology was significantly associated with poorer overall survival. As there are no significant differences in 5-year OS, DFS, and patterns of failure, definitive CRT could avoid the combined modality therapy without compromising oncologic outcomes.

The Clinical Significance and Utility of HPV-DNA Testing in Korean Women with Atypical Glandular Cells in Cervical Pap Tests: An Analysis of 311 Cases at a Single Institution.

The aim of this study is to analyze the correlation between clinically significant histologic results and HPV in women with AGC in pap test. Of the 311 women confirmed as AGC, 111 women (35.7%) was identified as positive for HPV. In the AGC analysis, cervical lesions were significantly more common in HPV positive group compared to HPV negative group (61.2 vs. 10.5%, p < 0.001). In contrast, endometrial lesions were not associated with HPV infection (8.1 vs. 4.5%, p = 0.12). The HPV-DNA testing in women with AGC may be a useful tool for predicting clinically significant cervical lesions.

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.

Inhibitory effects of α-Mangostin on T cell cytokine secretion via ORAI1 calcium channel and K+ channels inhibition.

BACKGROUND: As one of the main components of mangosteen (Garcinia mangostana), a tropical fruit, α-mangostin has been reported to have numerous pharmacological benefits such as anti-cancer, anti-inflammatory, and anti-allergic effects through various mechanisms of action. The effects of α-mangostin on intracellular signaling proteins is well studied, but the effects of α-mangostin on ion channels and its physiological effects in immune cells are unknown. Generation of intracellular calcium signaling is a fundamental step for T cell receptor stimulation. This signaling is mediated not only by the ORAI1 calcium channel, but also by potassium ion channels, which provide the electrical driving forces for generating sufficient calcium ion influx. This study investigated whether α-mangosteen suppress T cell stimulation by inhibiting ORAI1 and two kinds of potassium channels (Kv1.3 and KCa3.1), which are normally expressed in human T cells. METHODS: This study analyzed the inhibitory effect of α-mangostin on immune cell activity via inhibition of calcium and potassium ion channels expressed in immune cells. RESULTS: α-mangostin inhibited ORAI1 in a concentration-dependent manner, and the IC50 value was 1.27 ± 1.144 µM. Kv1.3 was suppressed by 41.38 ± 6.191% at 3 µM, and KCa3.1 was suppressed by 51.16 ± 5.385% at 3 µM. To measure the inhibition of cytokine secretion by immune cells, Jurkat T cells were stimulated to induce IL-2 secretion, and α-mangostin was found to inhibit it. This study demonstrated the anti-inflammatory effect of α-mangostin, the main component of mangosteen, through the regulation of calcium signals.

Ca2+ Sensitivity of Anoctamin 6/TMEM16F Is Regulated by the Putative Ca2+-Binding Reservoir at the N-Terminal Domain.

Anoctamin 6/TMEM16F (ANO6) is a dual-function protein with Ca2+-activated ion channel and Ca2+-activated phospholipid scramblase activities, requiring a high intracellular Ca2+ concentration (e.g., half-maximal effective Ca2+ concentration [EC50] of [Ca2+]i > 10 µM), and strong and sustained depolarization above 0 mV. Structural comparison with Anoctamin 1/TMEM16A (ANO1), a canonical Ca2+- activated chloride channel exhibiting higher Ca2+ sensitivity (EC50 of 1 µM) than ANO6, suggested that a homologous Ca2+-transferring site in the N-terminal domain (Nt) might be responsible for the differential Ca2+ sensitivity and kinetics of activation between ANO6 and ANO1. To elucidate the role of the putative Ca2+-transferring reservoir in the Nt (Nt-CaRes), we constructed an ANO6-1-6 chimera in which Nt-CaRes was replaced with the corresponding domain of ANO1. ANO6- 1-6 showed higher sensitivity to Ca2+ than ANO6. However, neither the speed of activation nor the voltage-dependence differed between ANO6 and ANO6-1-6. Molecular dynamics simulation revealed a reduced Ca2+ interaction with Nt- CaRes in ANO6 than ANO6-1-6. Moreover, mutations on potentially Ca2+-interacting acidic amino acids in ANO6 Nt- CaRes resulted in reduced Ca2+ sensitivity, implying direct interactions of Ca2+ with these residues. Based on these results, we cautiously suggest that the net charge of Nt- CaRes is responsible for the difference in Ca2+ sensitivity between ANO1 and ANO6.

Apoptotic effects of alisol B 23­acetate on gastric cancer cells.

Alisol B 23­acetate (AB23A) is a natural triterpenoid isolated from Alismatis rhizoma, which exhibits a number of pharmacological activities. In the present study, AB23A­induced anticancer efficacy was examined in AGS gastric cancer cells. Cell viability assay, cell cycle analysis, caspase activity assay, western blotting and reactive oxygen species (ROS) assay were used to investigate the anticancer effects of AB23A on AGS cells. AB23A reduced the viability of AGS cells, increased the sub­G1 cell fraction and depolarized the mitochondrial membrane. Notably, AB23A­induced cell death was associated with downregulation of the B­cell lymphoma 2 and survivin proteins, and upregulation of the Bax protein. In addition, AB23A increased caspase­3 and ­9 activities, and regulated the activation of mitogen­activated protein kinases (MAPK). Moreover, AB23A increased the production of reactive oxygen species. These results suggested that AB23A may induce apoptosis through cell cycle arrest and the mitochondrial pathway, accompanied by the caspase and MAPK signaling cascades. In conclusion, AB23A may have potential as a novel anticancer drug for the treatment of gastric cancer.