Pharmacological blockade of protease-Activated Receptor 2 improves airway remodeling and lung inflammation in experimental allergic asthma

Abstract Protease-activated receptors (PARs) are metabotropic G-protein-coupled receptors that are activated via proteolytic cleavage of a specific sequence of amino acids in their N-terminal region. PAR2 has been implicated in mediating allergic airway inflammation. This study aims to study the effect of PAR2 antagonist ENMD1068in lung inflammation and airway remodeling in experimental asthma. Allergic lung inflammation was induced in sensitized BALB/c mice through intranasal instillations of ovalbumin (OVA), and mice were pretreated with ENMD1068 1 hour before each OVA challenge. Bronchoalveolar lavage fluid (BALF) was collected, and the lungs were removed at different time intervals after OVA challenge to analyze inflammation, airway remodeling and airway hyperresponsiveness. Ovalbumin promoted leukocyte infiltration into BALF in a PAR2-dependent manner. ENMD1068 impaired eosinophil peroxidase (EPO) and myeloperoxidase (MPO) activity in the lung parenchyma into BALF and reduced the loss of dynamic pulmonary compliance, lung resistance in response to methacholine, mucus production, collagen deposition and chemokine (C-C motif) ligand 5 expression compared to those in OVA-challenged mice. We propose that proteases released after an allergen challenge may be crucial to the development of allergic asthma in mice, and PAR2 blockade may be useful as a new pharmacological approach for the treatment of airway allergic diseases.

Evaluation of the improvement of quality of life with Azithromycin in the treatment of eosinophilic nasal polyposis / Avaliação da melhora da qualidade de vida com o uso de Azitromicina no tratamento da polipose nasossinusal eosinofílica

ABSTRACT INTRODUCTION: The Sino-Nasal Outcome Test 22 (SNOT-22) is an important tool in assessing the quality of life (QoL) of patients with chronic rhinosinusitis with a validated version in Brazil. The eosinophilic nasal polyposis (ENP) represents most of the cases of nasal polyposis (85-90%) and belongs to the group of chronic rhinosinusitis. It is a chronic inflammatory disease that impacts the QoL of patients, not only causing localized symptoms, but also resulting in a general malaise. The standard treatments (corticosteroids and nasal endoscopic surgery) lead to partial control of symptoms, but relapses are frequent. Macrolide acting as an immunomodulator is a promising tool for more effective control of this disease. Studies are still lacking to assess the real impact on the QoL in patients treated with macrolides. OBJECTIVE: To evaluate the improvement of QL, evaluated using SNOT-22, in patients with PNSE treated with immunomodulatory dose azithromycin. METHODS: This is a paired experimental study in patients with ENP. Comparison of pre-treatment and post-treatment with azithromycin was performed. Patients completed the SNOT-22 questionnaire before the start of treatment and returned for evaluation after eight weeks of treatment. Azithromycin was prescribed at a dose of 500 mg, orally, three times a week, for 8 weeks. RESULTS: SNOT-22 score decreased 20.3 points on average. There was a significant decrease in the SNOT-22 (difference greater than 14 points) in 19 patients (57.6%). There was no significant difference in improvement in SNOT in subgroups with or without asthma/aspirin intolerance. CONCLUSION: Azithromycin resulted in significant improvement of QoL, assessed by SNOT-22, in the studied population.

RESUMO INTRODUÇÃO: O Sino-Nasal Outcome Test 22 (SNOT-22) está entre os principais instrumentos na avaliação da qualidade de vida dos pacientes com rinossinusite crônica, com versão validada no Brasil. A polipose nasossinusal eosinofílica (PNSE) representa a maioria dos casos de polipose nasossinusal (85% a 90%) e pertence ao grande grupo das rinossinusites crônicas. É uma doença inflamatória crônica que impacta sobremaneira a qualidade de vida (QV) dos pacientes, não só pelos sintomas locais, mas também por resultarem em um quadro de mal-estar geral. Os tratamentos padronizados (corticosteroides e cirurgia endoscópica nasal) levam ao controle parcial dos sintomas e as recidivas são frequentes. Os macrolídeos usados como imunomoduladores são uma promissora ferramenta para um controle mais eficaz dessa doença. Ainda faltam estudos para avaliar o real impacto na QV dos pacientes tratados com macrolídeos. OBJETIVO: Avaliar a melhora da QV do paciente portador de PNSE tratado com azitromicina em dose imunomoduladora baseando-se questionário SNOT-22. MÉTODO: Trata-se de estudo experimental autopareado em pacientes com PNSE. Foi realizada a comparação dos pacientes pré-tratamento e pós-tratamento com azitromicina. Os pacientes preencheram o questionário SNOT-22 antes do início do tratamento e no retorno após as oito semanas de tratamento. Foi prescrita azitromicina na dose de 500 mg, VO, três vezes por semana, durante 8 semanas. RESULTADOS: O valor do índice SNOT-22 dos pacientes reduziu 20,3 pontos, em média. Houve diminuição significativa do SNOT-22 (diferença maior que 14 pontos) em 19 pacientes (57,6%). Não houve uma diferença significativa na melhora do SNOT nos subgrupos com ou sem asma/intolerância à aspirina. CONCLUSÃO: A azitromicina resultou em melhora significativa da QV, avaliada pelo questionário SNOT-22, na população estudada.