Effect of piperlongumine during exposure to cigarette smoke reduces inflammation and lung injury.

Chronic obstructive pulmonary disease (COPD) is related to smoking and anti-inflammatory therapy is indicated. Among the mediators with anti-inflammatory properties, we highlight piperlongumine (PL), an alkaloid/amide of Piper longum. Here we evaluated the PL administration on an experimental model of respiratory inflammation resulting from exposure to cigarette smoke. Male Balb/c mice were exposed to burning of 10 commercial cigarettes, 2x/day, for five weeks on specific equipment. PL efficacy was evaluated in control, exposed to smoke without treatment and PL treated (2.0 mg/kg, 3x/week) groups. Animals were weighed and plethysmographic analyses performed at the end of the exposure protocol. Inflammatory cells were evaluated in the bronchoalveolar lavage (BAL) and hemoglobin and glucose in the blood. Lung fragments were processed for histopathological studies and AnxA1, COX-2, NF-kB and neutrophil elastase expressions. Plethysmography revealed that PL maintained pulmonary frequency, volume and ventilation parameters similar to controls, with respiratory volume reduction compared to untreated animals. Final weight was reduced in both exposed groups. PL decreased hemoglobin concentration, attenuated the reduction of glucose levels and reduced influx of lymphocytes, neutrophils and macrophages in BAL. Histopathologically occured infiltration of inflammatory cells, increase of the interalveolar septa and intra-alveolar spaces in untreated animals. But, PL administration recovered lung tissues and, immunohistochemically, promoted increased expression of AnxA1 and reduction of COX-2, NF-kB and neutrophil elastase. Together the results indicate that PL attenuates systemic and pulmonary inflammatory changes, partially by modulating the expression the endogenous AnxA1, and may represent a promising therapy in preventing the inflammation induced by cigarette smoke.

Mimetic peptide AC2-26 of annexin A1 as a potential therapeutic agent to treat COPD.

Chronic obstructive pulmonary disease (COPD) is related to inflammatory process caused by smoking habit. In this scenario, the anti-inflammatory protein Annexin A1 (AnxA1) may represent a therapeutic alternative. We performed experiments to evaluate the effects of the AnxA1 mimetic peptide Ac2-26 in an initial COPD model by physiological, histopathological, biochemical and immunohistochemical analyses. Weight loss, increased blood pressure, reductions in the pulmonary frequency and ventilation, loss of tracheal cilia, enlargement of the pulmonary intra-alveolar spaces and lymphoid tissue found in untreated smoke-exposed group were attenuated by AnxA1 peptide treatment. The Ac2-26 administration also protected against leukocytes influx in bronchoalveolar lavage (BAL), lung and trachea, and it also led to decreased hemoglobin, glucose, cholesterol, gamma glutamyl transferase and aspartato aminotransferase levels. Similarly, reduction of proinflammatory mediators and higher concentration of anti-inflammatory cytokine were found in macerated lung supernatant, blood plasma and BAL in the treated animals. Besides Ac2-26 group showed reduced tissue expressions of AnxA1, cyclooxygenase-2 and metalloproteinase-9, but formylated peptide receptor 2 (FPR2) overexpression. Our results all together highlighted the protective role of the Ac2-26 mimetic peptide in COPD with promising perspectives.

Expression profiles of Annexin A1, formylated peptide receptors and cyclooxigenase-2 in gastroesophageal inflammations and neoplasias.

The anti-inflammatory protein Annexin-A1 (ANXA1) is associated to tumor invasion process and its actions can be mediated by formylated peptides receptors (FPRs). Therefore, we evaluated the expression and correlation of ANXA1, FPR and cyclooxygenase-2 (COX-2) enzyme in esophageal and stomach inflammations and neoplasias. The study of proteins was performed by immunohistochemistry in biopsies of esophagitis, Barrett's esophagus, squamous cell carcinoma and adenocarcinoma of the esophagus, as well as gastritis, stomach polypus and gastric adenocarcinoma. The intensity of the expressions was evaluated by densitometry. The immunohistochemical and densitometric analyzes showed specificity for the FPR1 receptor and modulation of the ANXA1, COX-2 and FPR1 expressions in the epithelial cells in the different studied conditions. Increased immunoreactivity of these proteins was observed in cases of inflammation and stomach polypus. Interestingly, moderate immunoreactivity for ANXA1 and FPR1 but increased immunolabeling for COX-2 were observed in Barrett́s esophagus and esophageal adenocarcinomas. Also, there was reduced expression of ANXA1 and FPR1 in esophageal carcinoma but COX-2 overexpression in this tumor. There was no expression of FPR2 but ANXA1 and FPR1 expressions were positively correlated in all clinical conditions studied. Positive correlation between ANXA1 and COX-2 were also observed in inflammation conditions while negative correlation between ANXA1 and COX-2 was observed in esophageal carcinoma. Our results demonstrate the unregulated expression of ANXA1 and COX-2 in precursor lesions of esophageal and stomach cancers, reinforcing their involvement in gastroesophageal carcinogenesis. In addition, the data show that the actions of ANXA1 in the inflammatory and neoplastic processes of the esophagus and stomach are specifically mediated by the FPR1 receptor.