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.

Efeito antiinflamatório da folha de batata-doce (Ipomoea batatas) / Anti-inflammatory effects of sweet potato leaves (Ipomoea batatas)

Neste trabalho testamos os efeitos antiinflamatórios do extrato hidroalcoólico de folhas de Ipomoea batatas. O modelo experimental de inflamaçäo utilizado foi de edema de pata de ratos induzido pelo composto 48/80. Apesar de ser comumente utilizada na medicina popular, esse tipo de extrato näo apresentou nenhum efeito antiinflamatório no modelo experimental utilizado

Efeito da inibiçäo crônica do óxido nítrico no rim de ratos diabéticos / Effect of nitric oxide chronic inhibition on kidney of diabetic rats

O presente trabalho teve como finalidade analisar o efeito de um inibidor do óxido nítrico no rim de ratos normais e diabéticos. Observamos que L-NG-nitro arginina metil éster (L-NAME), além de causar hipertensäo arterial, näo teve nenhum efeito na morfologia renal e, também näo atenuou a diabetes pela inibiçäo da produçäo do NO. O conhecimento sobre a produçäo de NO por ilhotas de Langerhans ainda precisa ser melhor estudado, porém este é um modelo eficaz para estudo de hipertensäo