Individualized treatment for allergic rhinitis based on key nasal clinical manifestations combined with histamine and leukotriene D4 levels / Tratamento individualizado para a rinite alérgica baseado nas principais manifestações clínicas nasais e dos níveis de histamina e leucotrieno D4

Abstract Introduction The types of allergic rhinitis are roughly classified based on the causative antigens, disease types, predilection time, and symptom severity. Objective To examine the clinical typing and individualized treatment approach for allergic rhinitis and to determine the optimal treatment method for this disease using various drug combination therapies. Methods A total of 108 participants with allergic rhinitis were divided into three groups based on symptoms. Subsequently, each group was further categorized into four subgroups based on the medications received. The efficacy of the treatments was evaluated using the visual analog scale VAS scores of the total and individual nasal symptoms, decline index of the symptom score, histamine and leukotriene levels, and mRNA and protein expression levels of histamine 1 and cysteinyl leukotriene 1 receptors. Results Loratadine + mometasone furoate and loratadine + mometasone furoate + montelukast significantly improved the sneezing symptom and reduced the histamine levels compared with the other combination therapies (p < 0.05). Meanwhile, montelukast + mometasone furoate and montelukast + mometasone furoate + loratadine considerably improved the nasal obstruction symptom and decreased the leukotriene D4 levels compared with the other combination therapies (p < 0.05). Conclusion Clinical symptom evaluation combined with experimental detection of histamine and leukotriene levels can be an objective and accurate method to clinically classify the allergic rhinitis types. Furthermore, individualized treatment based on allergic rhinitis classification can result in a good treatment efficacy.

Resumo Introdução A rinite alérgica é basicamente classificada de acordo com os antígenos causadores, tipos de doença, peridiocidade e gravidade dos sintomas. Objetivo Avaliar os tipos clínicos e a abordagem terapêutica individualizada para cada tipo de rinite alérgica e determinar o método de tratamento ideal utilizando várias terapias de combinação de fármacos. Método Um total de 108 participantes com rinite alérgica foram divididos em três grupos com base nos sintomas. Posteriormente, cada grupo foi subsequentemente categorizado em quatro subgrupos com base nos medicamentos recebidos. A eficácia dos tratamentos foi avaliada utilizando os escores da escala visual analógica EVA dos sintomas nasais totais e individualmente, índice de declínio do escore de sintomas, níveis de histamina e leucotrienos e níveis de expressão de mRNA e proteína dos receptores de histamina 1 e cisteinil-leucotrieno 1. Resultados As associações entre loratadina + furoato de mometasona, assim como a de loratadina + furoato de mometasona + montelucaste melhoraram significativamente o sintoma de espirros e reduziram os níveis de histamina em comparação às outras terapias combinadas (p < 0,05). Por outro lado, a associação montelucaste + furoato de mometasona, assim como a associação montelucaste + furoato de mometasone + loratadina melhoraram consideravelmente o sintoma de obstrução nasal e diminuíram os níveis de leucotrieno D4 em comparação com as outras combinações (p < 0,05). Conclusão A avaliação clínica dos sintomas combinada com a detecção experimental dos níveis de histamina e leucotrieno pode ser um método objetivo e preciso para classificar clinicamente os tipos de rinite alérgica. Além disso, o tratamento individualizado baseado na classificação da rinite alérgica pode resultar no aumento da eficácia do tratamento.

Effects of cysteinyl leukotriene receptors on phagocytosis of mouse microglial cells / 浙江大学学报·医学版

OBJECTIVE@#: To determine the effects of cysteinyl leukotriene receptors (CysLTR and CysLTR) on phagocytosis of mouse BV2 microglial cells.@*METHODS@#: BV2 cells were stimulated with microglial activators lipopolysaccharide (LPS) or CysLT receptor agonists LTD. The phagocytosis of BV2 cells was observed by immunofluorescence analysis and flow cytometry. The intracellular distributions of CysLTR and CysLTR in BV2 cells were examined with immunofluorescence staining.@*RESULTS@#: Both LPS and LTD could significantly enhance the phagocytosis of BV2 cells, and such effect could be inhibited by CysLTR selective antagonist Montelukast and CysLTR selective antagonist HAMI 3379. The activation of BV2 cells induced by LTD or LPS resulted in changes in intracellular distributions of CysLTR and CysLTR. CysLTR and CysLTR was co-localization with a similar distribution.@*CONCLUSIONS@#: CysLTR and CysLTR regulate the phagocytosis of mouse BV2 microglial cells with a synergistic effect.

Effects of cysteinyl leukotrienes receptor antagonists on chronic brain injury after global cerebral ischemia/reperfusion / 浙江大学学报·医学版

OBJECTIVE@#: To investigate the effects of cysteinyl leukotrienes receptor (CysLTR) antagonists on global cerebral ischemia/reperfusion (CI/R) injury in gerbils, and to explore its mechanism.@*METHODS@#: Totally 40 gerbils weighting 45-65 g were randomized into sham, saline, Pranlukast and HAMI 3379 groups with 10 animals in each. The CI/R model was established in gerbils by bilateral common carotid occlusion for 10 min followed by reperfusion. After ischemia, the CysLTR antagonists Pranlukast (0.1 mg/kg) and HAMI 3379 (0.1 mg/kg) were injected intraperitoneally for 5 consecutive days in the last two groups,while the former two groups were injected with saline only (10 mL/kg). After 24 h or 14 d reperfusion, neurological deficit score was evaluated and the behavioral dysfunction was assessed, respectively. And 14 d after reperfusion, the neuron morphology of cerebral cortex was observed in brain sections stained with Cresyl violet. In addition, the Iba-1 (microgila) and GFAP (astrocyte) positive cells in cerebral cortex were observed by using immunohistochemitry method.@*RESULTS@#: CI/R models were successfully established in 21 out of 30 gerbils with 7 in saline group, 6 in Pranlukast group, and 8 in HAMI 3379 group. Compared with saline group, Pranlukast and HAMI 3379 significantly attenuated neurological deficits, improved the behavioral function 24 h after reperfusion(all 0.05). In addition, Pranlukast and HAMI 3379 also inhibited the neuron loss and injury, suppressed microgila and astrocyte activation 14 d after reperfusion(all <0.01).@*CONCLUSIONS@#: CysLTR antagonists Pranlukast and HAMI 3379 have long-term neuroprotective effect on chronic brain injury induced by global cerebral ischemia/reperfusion in gerbils.

Add-on Therapy for Symptomatic Asthma despite Long-Acting Beta-Agonists/Inhaled Corticosteroid / 결핵

Asthma, remains symptomatic despite ongoing treatment with high doses of inhaled corticosteroids (ICS) in conjunction with long-acting beta-agonists (LABA), is classified as “severe” asthma. In the course of caring for those patients diagnosed with severe asthma, stepping up from ICS/LABA to more aggressive therapeutic measures would be justified, though several aspects have to be checked in advance (including inhaler technique, adherence to therapy, and possible associated comorbidities). That accomplished, it would be advisable to step up care in accordance with the Global Initiative for Asthma (GINA) recommendations. Possible strategies include the addition of a leukotriene receptor antagonist or tiotropium (to the treatment regimen). The latter has been shown to be effective in the management of several subgroups of asthma. Oral corticosteroids have commonly been used for the treatment of patients with severe asthma in the past; however, the use of oral corticosteroids is commonly associated with corticosteroid-related adverse events and comorbidities. Therefore, according to GINA 2017 these patients should be referred to experts who specialize in the treatment of severe asthma to check further therapeutic options including biologics before starting treatment with oral corticosteroids.

Factors associated with the treatment of chronic spontaneous urticaria in children

PURPOSE: Chronic spontaneous urticaria (CSU) in children is a common skin disorder, but its clinical course varies. We investigated the clinical course and associated factors for CSU treatment in children. METHODS: A total of 107 children, diagnosed with CSU from 2001 to 2016 in Dong-A University Hospital, who had been followed up for more than 6 months after treatment, were enrolled. The laboratory findings, and clinical aspects and courses were retrospectively investigated by a medical record review. We divided the 152 patients into 3 groups according to the treatment modalities: group 1, 1 antihistamine; group 2, more than 2 kinds of antihistamines; and group 3, antihistamines plus leukotriene receptor antagonist. RESULTS: The mean age of patients in group 3 was 3.4 years (range, 2.6–4.2 years), which was significantly lower than those at the other 2 group patients (P=0.01). The urticaria activity score (UAS) of group 3 (6.1 [5.7–6.6]) was significantly higher compared to those of the other 2 groups (P=0.01). The improvement rate of the condition in children with positive specific immunoglobulin E (sIgE) reactivity to food or inhalant allergens was significantly lower than that of children with negative sIgE reactivity (P=0.01). Sex, age, history of allergic diseases, disease duration, UAS, previous treatment, and treatment modality were not correlated with the symptom improvement rate. CONCLUSION: Younger children and those with higher UAS needed more medication to ensure the improvement in symptoms. Moreover, it took more time for the improvement in symptoms in children who were sensitized to food or inhalant allergens.

Successful desensitization of a patient with albumin hypersensitivity

There have been few cases of albumin hypersensitivity reported, and there is limited information on this condition. When a patient is anaphylactic to a certain drug and no alternative drug is available to treat the underlying condition, desensitization is a reasonable option and can be performed successfully to treat the patient. A standard 12-step, 3-solution rapid desensitization protocol allows the safe readministration of a medication after certain types of immediate hypersensitivity. However, we demonstrated that a new 10-step, 1-solution desensitization protocol using antihistamine and leukotriene receptor antagonist as premedications, which was effective and safe in a patient with hypersensitivity. We report a 13-year-old boy with Gorham-stout syndrome who was presented with newly acquired albumin anaphylaxis and successfully treated with the 10-step rapid drug desensitization protocol.

Montelukast reduces seizures in pentylenetetrazol-kindled mice

Cysteinyl leukotrienes (CysLTs) have been implicated in seizures and kindling; however, the effect of CysLT receptor antagonists on seizure frequency in kindled animals and changes in CysLT receptor expression after pentylenetetrazol (PTZ)-induced kindling have not been investigated. In this study, we evaluated whether the CysLT1 inverse agonist montelukast, and a classical anticonvulsant, phenobarbital, were able to reduce seizures in PTZ-kindled mice and alter CysLT receptor expression. Montelukast (10 mg/kg, sc) and phenobarbital (20 mg/kg, sc) increased the latency to generalized seizures in kindled mice. Montelukast increased CysLT1 immunoreactivity only in non-kindled, PTZ-challenged mice. Interestingly, PTZ challenge decreased CysLT2 immunoreactivity only in kindled mice. CysLT1 antagonists appear to emerge as a promising adjunctive treatment for refractory seizures. Nevertheless, additional studies are necessary to evaluate the clinical implications of this research.

A Double-Blind, Randomized, Crossover Study to Compare the Effectiveness of Montelukast on Atopic Dermatitis in Korean Children

PURPOSE: Some studies report a role of leukotrienes in the pathogenesis of atopic dermatitis and suggest a rationale for the use of leukotriene receptor antagonist (LTRA) in the treatment of atopic dermatitis. This study aimed to evaluate the treatment effectiveness of montelukast in children with atopic dermatitis. METHODS: Fifty-four children between the ages of 2 and 6 years with moderate to severe atopic dermatitis were enrolled. Group A received montelukast for 8 weeks, followed by a crossover to 8 weeks of placebo after a 2-week washout period. Group B reversed the administration according to a randomized, double-blind, placebo-controlled, crossover design. The SCORing atopic dermatitis (SCORAD) index, urinary leukotriene E4 (LTE4), and eosinophil-derived neurotoxin (EDN) were assessed at every visit. RESULTS: Forty-three patients (21 males) completed the study. Although the SCORAD index was decreased in both groups, there was no statistically significant difference between montelukast and placebo (-3.0±11.2 vs -5.7±11.3, P=0.43). The level of urinary LTE4 was decreased after taking montelukast when compared to placebo, but there was no statistically significant difference (-65.9±556.2 vs 87.7±618.3, P=0.26). The changes in urinary EDN after taking montelukast and placebo had no significant difference (37.0±1,008.6 vs -195.8±916.7, P=0.10). When analyzing SCORAD indices, urinary LTE4, and EDN, we could not prove the effectiveness of montelukast in the atopic, non-atopic or high ECP (ECP ≥15 µg/L) subgroups. CONCLUSIONS: There was no statistically significant difference in clinical improvement or biomarkers between montelukast and placebo treatment. Therefore, conventional treatments with skin care and infection control might be more important strategies in the treatment of atopic dermatitis.

Capsular Contracture after Breast Augmentation: An Update for Clinical Practice

Capsular contracture is the most common complication following implant based breast surgery and is one of the most common reasons for reoperation. Therefore, it is important to try and understand why this happens, and what can be done to reduce its incidence. A literature search using the MEDLINE database was conducted including search terms 'capsular contracture breast augmentation', 'capsular contracture pathogenesis', 'capsular contracture incidence', and 'capsular contracture management', which yielded 82 results which met inclusion criteria. Capsular contracture is caused by an excessive fibrotic reaction to a foreign body (the implant) and has an overall incidence of 10.6%. Risk factors that were identified included the use of smooth (vs. textured) implants, a subglandular (vs. submuscular) placement, use of a silicone (vs. saline) filled implant and previous radiotherapy to the breast. The standard management of capsular contracture is surgical via a capsulectomy or capsulotomy. Medical treatment using the off-label leukotriene receptor antagonist Zafirlukast has been reported to reduce severity and help prevent capsular contracture from forming, as has the use of acellular dermal matrices, botox and neopocket formation. However, nearly all therapeutic approaches are associated with a significant rate of recurrence. Capsular contracture is a multifactorial fibrotic process the precise cause of which is still unknown. The incidence of contracture developing is lower with the use of textured implants, submuscular placement and the use of polyurethane coated implants. Symptomatic capsular contracture is usually managed surgically, however recent research has focussed on preventing capsular contracture from occurring, or treating it with autologous fat transfer.

Clinical significance of cysteinyl leukotriene receptor expression in primary hepatocellular carcinoma / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate expression of the cysteinyl leukotriene receptor (CysLT1R) in hepatocellular carcinoma (HCC) tissues and determine its clinical significance.</p><p><b>METHODS</b>Cancerous and paraneoplastic liver tissues were collected from 30 patients with HCC and from 12 patients with liver hemangioma patients (controls). Real-time PCR and immunohistochemistry were used to evaluate the expression of CysLT1R in these tissues and assess the relationship with clinical pathological features. T-test,?Fisher's exact test and Kaplan-Meier survival analysis were used for statistical analysis.</p><p><b>RESULTS</b>The expression of CysLT1R in adjacent liver tissues (100%) was higher than that in the HCC (43.33%, P = 0.000) and normal liver tissues (41.67%, P = 0.000). The level of CysLT1R mRNA was also higher in paraneoplastic liver tissues (0.0339+/-0.0221) than in the paired HCC tissues (0.0127+/-0.0116, t = 2.911, P = 0.008) and normal liver tissues (0.0154+/-0.0123, t = -2.310, P = 0.033). There was no difference between the levels in HCC and normal liver tissues (P more than 0.05). Higher level of CysLT1R mRNA, higher level of serum alpha-fetoprotein, and higher tumor stage (III-IV) were associated with poor prognosis (respectively 4.372, P = 0.037; 24.187, P = 0.000; 8.75, P = 0.003). However, no evident relationship between the expression of CysLT1R and other clinical features was observed. Conclusions Overexpression of CysLT1R may contribute to the occurrence and progression of HCC.</p>

Expression of CysLTR-1 and CysLTR-2 in adenoid tissues from children with adenoid hypertrophy / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To examine the expression of cysteinyl leukotriene receptor-1 (CysLTR-1) and cysteinyl leukotriene receptor-2 (CysLTR-2) in the adenoid tissues from children with adenoid hypertrophy (AH) and to explore the role of leukotrienes in the pathogenesis of AH.</p><p><b>METHODS</b>Sixty children with AH who were treated by adenoidectomy and/or tonsillectomy were classified into two groups: simple AH and AH plus allergic rhinitis (n=30 each). Twenty children who underwent tonsillectomy due to recurrent purulent tonsillitis were selected as the control group. The expression of CysLTR-1 and CysLTR-2 in the excised tonsil and/or adenoid tissues was determined by immunofluorescence histochemical labeling and integrated optical density measurement.</p><p><b>RESULTS</b>The expression of CysLTR-1 and CysLTR-2 in the adenoid and tonsil tissues increased significantly in both the simple AH group and AH plus allergic rhinitis group compared with the control group (P<0.01). The expression of CysLTR-1 and CysLTR-2 in the AH plus allergic rhinitis group increased more significantly compared with the simple AH group (P<0.01).</p><p><b>CONCLUSIONS</b>CysLTR-1 and CysLTR-2 are highly expressed in the adenoid tissues from children with AH, suggesting that leukotrienes are involved in the pathogenesis of AH.</p>

Expression and distribution of cysteinyl leukotriene receptors CysLT1R and CysLT2R, and GPR17 in brain of Parkinson disease model mice / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To examine the spatiotemporal profiles and localization of CysLT1R, CysLT2R and GPR17 in mice with 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced Parkinson disease (PD).</p><p><b>METHODS</b>PD model was induced by subcutaneous injection of MPTP (25 mg/kg) for 5 d in adult male C57BL/6 mice. At d10 after MPTP injection, the expression and cellular localization of CysLT1R, CysLT2R and GPR17 in the substantia nigra were detected by immunohistochemistry and immunofluorescence.</p><p><b>RESULTS</b>CysLT1R, CysLT22 and GPR17 were normally localized in TH-positive dopaminergic neurons and microglia, while CysLT2R was also expressed in astrocytes. In dopaminergic neurons, approximately 91% co-expressed GPR17, 77% co-expressed CysLT1R and 52% co-expressed CysLT2R. Compared with the control group, TH-positive cells in the substantia nigra were significantly reduced in PD mice. CysLT1R, CysLT2R and GPR17-positive cells were significantly reduced; and CysLT1R, CysLT2R, GPR17-positive dopaminergic neurons were also significantly reduced in the PD group. In the striatum, both CysLT1R and GPR17 were normally expressed in neurons; whereas CysLT2R was expressed in astrocytes. In PD striatum, CysLT1R and GPR17-positive cells were decreased, but CysLT2R expression was significantly increased which mainly expressed in the proliferating astrocytes.</p><p><b>CONCLUSION</b>CysLT1R, CysLT2R and GPR17 may be involved in the MPTP-induced PD damage in mice.</p>

Leukotriene D4 activates BV2 microglia in vitro / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effects of CysLT receptor agonist leukotriene D4(LTD4) and antagonists on activation of microglia BV2 cells.</p><p><b>METHODS</b>The expression of CysLT1 and CysLT2 protein was determined by Western blotting and immunostaining in microglia BV2 cells. BV2 cells were pretreated with or without CysLT1 receptor selective antagonist montelukast, CysLT2 receptor selective antagonist HAMI 3379, or CysLT1/CysLT2 receptor dual antagonist BAY u9773 for 30 min, then the cells were treated with LTD4 for 24 h. Cell viability was detected by MTT reduction assay. Phagocytosis and mRNA expression of IL-6 were determined by fluorescent bead tracking and RT-PCR, respectively.</p><p><b>RESULTS</b>In BV2 cells, LTD4 did not affect proliferation but significantly enhanced phagocytosis and increased IL-6 mRNA expression in a concentration-dependent manner. LTD4 at 100 nmol/L induced a 1.4-fold increase of phagocytic index and a 2-fold up-regulation of IL-6 mRNA expression (P<0.01). HAMI 3379 and BAY u9773 (100 nmol/L) further increased LTD4-induced phagocytosis; BAY u9773 and montelukast decreased LTD4-induced IL-6 mRNA expression, while HAMI 3379 had no effect on that.</p><p><b>CONCLUSION</b>LTD4 activates BV2 cells in vitro and enhances IL-6 mRNA expression mediated by CysLT1 receptor, LTD4 induces phagocytosis which might be negatively regulated by CysLT2 receptor in BV2 cells.</p>

Therapeutic Effect of Combination Treatment of Antihistamine and Montelukast in Allergic Rhinitis

BACKGROUND: Montelukast is a type 1 cysteinyl-leukotrienes receptor antagonist that has been widely used in allergic disease. However, the effect of combination of leukotriene receptor antagonist and antihistamine is controversial. The aim of this study was to compare the effect of combination treatment of montelukast and antihistamine, fexofenadine, over antihistamine alone in patients with allergic rhinitis (AR). SUBJECTS AND METHODS: Retrospective chart review of 60 patients with AR was undertaken. Patients were classified into combination group (montelukast and fexofenadine, n=28) and antihistamine only group (fexofenadine, n=32) according to treatment modalities. Questionnaire survey was performed and allergic symptoms (VAS scale, 5pointscale), and SNOT (sinonasal outcome test)-20 score were obtained before and after the treatment. RESULTS: Mean follow-up duration was 6.7+/-4.6weeks. There was no significant difference in demographic data between two groups. Allergic symptoms and SNOT-20 score(nasal, QOL domain) were improved significantly in both groups after the treatment (all p 0.05, respectively). CONCLUSION: A combination treatment of montelukast and fexofenadine showed more efficacies in nasal obstruction than single fexofenadine treatment in patients with AR. Therefore, montelukast could be used effectively with antihistamine in patients with AR complaining nasal congestion.

Bloqueio do receptor de leucotrieno CysLT1 em pacientes com fenômeno de Raynaud: evidência capilaroscópica do papel do leucotrieno / CysLT1 receptor inhibition in patients with Raynaud's phenomenon: capillaroscopic evidence of the role of leukotriene

OBJETIVO: Avaliar a ação do medicamento inibidor do receptor de leucotrieno CysLT1 (montelucaste) nas alterações vasculares das mãos em pacientes com fenômeno de Raynaud. MÉTODOS: Foram selecionadas pacientes com fenômeno de Raynaud secundário à doença inflamatória do tecido conjuntivo, excluindo tabagismo, hipertensão arterial e diabetes mellitus. As pacientes mantiveram a medicação prévia e iniciaram o uso de montelucaste 10 mg/dia por 60 dias. Foi realizada capilaroscopia periungueal dos dedos das mãos antes do uso da medicação e após 30 e 60 dias. A análise estatística foi feita por meio de porcentagem, média, desvio-padrão e teste exato de Fisher, com intervalo de confiança de 95 por cento. RESULTADOS: Foram estudadas cinco pacientes mulheres, brancas, com fenômeno de Raynaud secundário a doenças do tecido conjuntivo, das quais três apresentavam esclerodermia e duas apresentavam doença mista do tecido conjuntivo. A média de idade foi de 42,4 ± 12,4 anos, e a média de tempo de doença foi de 9,6 ± 4,8 anos. As pacientes estavam em uso de até 20 mg/dia de prednisona (pacientes com doença mista do tecido conjuntivo), nifedipina, pentoxifilina. As medicações foram mantidas. Após o uso de inibidor de receptor de leucotrieno por dois meses, o controle com capilaroscopia ungueal demonstrou diminuição do edema e da palidez e normalização do número, tamanho e distribuição dos capilares. CONCLUSÃO: O uso do montelucaste modificou as alterações capilares observadas na capilaroscopia periungueal de pacientes com fenômeno de Raynaud.

OBJECTIVE: To assess the effect of the leukotriene receptor inhibitor (montelukast) on vascular alterations in fingers of patients with Raynaud's phenomenon. METHODS: Patients with Raynaud's phenomenon of the hands secondary to inflammatory connective tissue disease were selected, and those with the following characteristics were excluded: smokers, arterial hypertension, and diabetes mellitus. All patients maintained their previous medications and started the use of montelukast, 10 mg/day, for 60 days. Naifold capillaroscopy of fingers was performed before the use of medication and after 30 and 60 days. Statistical analysis was performed with percentage, media, standard deviation, Fisher exact test, with 95 percent of confidence interval. RESULTS: The study assessed five Caucasian, female patients with Raynaud's phenomenon secondary to inflammatory connective tissue disease (three with scleroderma and two with mixed connective tissue disease), aged 42.4 ± 11.5 years, and with 9.6 ± 4.8 years of disease duration. Patients were on nifedipine and pentoxifylline, and those with mixed connective tissue disease were also on prednisone. The medications were maintained. After using montelukast for two months, nailfold capillaroscopy showed a reduction in edema and pallor, and normalization of capillary number, size, and distribution. CONCLUSION: The use of montelukast modified the capillary abnormalities observed on nailfold capillaroscopy of patients with Raynaud's phenomenon.

Cysteinyl leukotriene receptor 1 is involved in rotenone-induced injury of PC12 cells / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate whether cysteinyl leukotriene receptor 1 (CysLT₁ receptor) is involved in rotenone-induced injury of PC12 cells.</p><p><b>METHODS</b>After 24 h treatment with rotenone or with rotenone and the CysLT₁ receptor antagonist montelukast, PC12 cell viability was determined by the colorimetric MTT reduction assay. After PC12 cells were treated with various concentrations of rotenone for 24 h or with 3 μmol/L rotenone for various durations, the expression of CysLT(1) receptor was determined by Western blotting, and its intracellular distribution was detected by immunocytochemistry.</p><p><b>RESULTS</b>Rotenone (0.3-30 μmol/L) induced PC12 cell injury; this injury was significantly attenuated by montelukast at 1 and 5 μmol/L.The expression of CysLT(1) receptor increased after rotenone treatment at 1-10 μmol/L, or at 3 μmol/L for 3 and 24 h. Rotenone caused concentration-and time-dependent translocation of CysLT₁ receptor from the nucleus to the cytosol.</p><p><b>CONCLUSION</b>Cysteinyl leukotriene receptor 1 is involved in rotenone-induced injury of PC12 cells.</p>

The Effects of Anti-histamine and Leukotriene Receptor Antagonist Against Ischemia-Reperfusion Injury

PURPOSE: The purpose of this study was to investigate the role of mast cells and their product, histamine and leukotriene in ischemia-reperfusion injury. METHODS: Forty Sprague-Dawley rats were divided into four groups. (Group I: Control group without ischemia, Group II: Normal saline with ischemia, Group III: Cimetidine with ischemia, Group IV: Zafirlukast with ischemia) Skin flap was elevated and ischemic insult was given by clamping the artery for 12 hours. Before reperfusion, the rats were treated with saline, cimetidine and zafirlukast. Flap survival was evaluated at 7 days. Neutrophil counts, mast cell counts were evaluated 24 hours after reperfusion. RESULTS: Flap survival rate in the control group was 92.33%, whereas normal saline group had 37.34% survivals. Cimetidine and zafirlukast treated group showed significantly higher survival rates than normal saline group. The neutrophil and mast cell counts in cimetidine and zafirlukast treated group were significantly decreased than normal saline group. Cimetidine treated group showed higher survival rate and lower cell counts than zafirlukast treated group. CONCLUSION: The administration of cimetidine and zafirlukast can decrease neutrophils and mast cells caused by ischemia-reperfusion and increase flap survivals. It is suggests that antihistamine and leukotriene receptor antagonist have protective effect against ischemia-reperfusion injury to skin flap in rat.

Construction of HEK293 cell lines expressing hCysLT₂ receptor and its application in screening of antagonists / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To construct HEK293 cell lines stably expressing hCysLT(2) receptor, and to evaluate its application in screening of synthetic compounds with antagonist activity.</p><p><b>METHODS</b>The recombinant plasmid pcDNA3.1(+)-hCysLT(2) was transfected into HEK293 cells using Lipofectamin 2000. The transfected HEK293 cells were selected in 96 well plates by limiting dilution with 600 μg/ml C418 for 8 weeks. The expression of human CysLT(2) receptor was detected by RT-PCR and immunofluorescence staining. In HEK293 cells stably transfected with hCysLT(2), the agonist LTD(4)-induced elevation of intracellular calcium concentration ([Ca2(+)]i) was measured as the index for screening compounds with antagonist activity.</p><p><b>RESULT</b>After selection in 96 well plates by limiting dilution, 12 monoclones were obtained and 11 of them highly expressed hCysLT(2) receptor. The positive control ATP at 50 μmol/L and LTD(4) at 100 nmol/L elevated [Ca2(+)]i in hCysLT(2)-HEK293 cells. AP-2100984 inhibited LTD(4)-induced [Ca2(+)]i elevation, but selective CysLT(1) receptor antagonists did not exert such an effect. The newly synthesized compounds DXW2, DXW3, DXW4, DXW5, DXW9, DXW25, DXW26, DXW29 and DXW35 at 1 μmol/L significantly inhibited LTD(4)-induced [Ca2(+)]i elevation. The IC(50) values of DXW4 and DXW5 were 0.25 μmol/L and 7.5 μmol/L.</p><p><b>CONCLUSION</b>HEK293 cell lines stably expressing hCysLT(2) receptor have been successfully constructed, and can be used to screen compounds with CysLT(2) receptor antagonist activity.</p>

Rotenone-induced changes of cysteinyl leukotriene receptor 1 expression in BV2 microglial cells / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To prepare and identify a polyclonal antibody (pAb) against (mouse) cysteinyl leukotriene receptor 1 (CysLT(1)) and to investigate the changes of CysLT(1) receptor expression in BV2 microglial cells after rotenone treatment.</p><p><b>METHODS</b>Rabbits were immunized with KLH-coupled CysLT(1) peptide to prepare the pAb. The titer of the pAb in rabbit plasma was detected by ELISA method, and the specificity of the pAb was tested by antigen blockade. After BV2 cells were treated with rotenone (0.01-1 μmol/L) for 24 h, the expression of CysLT(1) was determined by immunostaining, Western blotting and RT-PCR.</p><p><b>RESULT</b>The pAb showed a titer of 1/32728, and was not cross-reacted with antigens of CysLT(2) receptor and GPR17. Immunostaining, Western blotting and RT-PCR analysis showed the expression of CysLT(1) receptor in BV2 microglia. Rotenone at 1μmol/L significantly induced an increased expression of CysLT(1) receptor.</p><p><b>CONCLUSION</b>The prepared CysLT(1) receptor polyclonal antibody has a high titer and high specificity to meet testing requirements of Western blotting and immunostaining; CysLT(1) is associated with rotenone-induced injury of BV2 microglial cells.</p>

Effects of agonist and antagonist of cysteinyl leukotriene receptors on differentiation of rat glioma C6 cells / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the role of cysteinyl leukotriene (CysLT) receptors in the differentiation of rat glioma C6 cells.</p><p><b>METHODS</b>Rat glioma C6 cells were treated with the agonist LTD(4), the CysLT(1) receptor antagonist montelukast and the differentiation inducer forskolin. Cell morphology and GFAP protein expression were determined after treatments.</p><p><b>RESULT</b>Forskolin (10 μmol/L) induced morphological changes and GFAP protein expression (cell differentiation) in C6 cells, but LTD(4) (0.1-100 nmol/L) did not induce these changes. Montelukast (1 μmol/L) alone did not affect C6 cell differentiation, while it induced the differentiation when combined with the LTD(4) (100 nmol/L).</p><p><b>CONCLUSION</b>The CysLT(2) receptor may modulate the differentiation of rat glioma C6 cells.</p>