Comparison of the Effects of Aerobic Conditioning Before and After Pulmonary Allergic Inflammation

Angiotensin-(1-7)/Mas receptor modulates anti-inflammatory effects of exercise training in a model of chronic allergic lung inflammation

AIMS

Exercise training increases circulating and tissue levels of angiotensin-(1-7) [Ang-(1-7)], which was shown to attenuate inflammation and fibrosis in different diseases. Here, we evaluated whether Ang-(1-7)/Mas receptor is involved in the beneficial effects of aerobic training in a chronic model of asthma.

MATERIAL AND METHODS

BALB/c mice were subjected to a protocol of asthma induced by ovalbumin sensitization (OVA; 4 i.p. injections) and OVA challenge (3 times/week for 4 weeks). Simultaneously to the challenge period, part of the animals was continuously treated with Mas receptor antagonist (A779, 1 μg/h; for 28 days) and trained in a treadmill (TRE; 60% of the maximal capacity, 1 h/day, 5 days/week during 4 weeks). PGC1-α mRNA expression (qRT-PCR), plasma IgE and lung cytokines (ELISA), inflammatory cells infiltration (enzymatic activity assay) and airway remodeling (by histology) were evaluated.

KEY FINDINGS

Blocking the Mas receptor with A779 increased IgE and IL-13 levels and prevented the reduction in extracellular matrix deposition in airways in OVA-TRE mice. Mas receptor blockade prevented the reduction of myeloperoxidase activity, as well as, prevented exercise-induced IL-10 increase. These data show that activation of Ang-(1-7)/Mas receptor pathway is involved in the anti-inflammatory and anti-fibrotic effects of aerobic training in an experimental model of chronic asthma.

SIGNIFICANCE

Our results support exercise training as a non-pharmacological tool to defeat lung remodeling induced by chronic pulmonary inflammation. Further, our result also supports development of new therapy based on Ang-(1-7) or Mas agonists as important tool for asthma treatment in those patients that cannot perform aerobic training.

Anti-Asthmatic Effects of Ginsenoside Rb1 in a Mouse Model of Allergic Asthma Through Relegating Th1/Th2

The aim of the study was to investigate the anti-asthma effects of ginsenoside Rb1 (Rb1) and its possible mechanisms. A total of 50 mice were randomly assigned to five experimental groups: control, model, dexamethasone (2 mg/kg), and Rb1 (10 and 20 mg/kg). Airway resistance (RI) was measured; histological studies were evaluated by the hematoxylin and eosin (HE) staining; Th1/Th2, ovalbumin (OVA)-specific serum, and bronchoalveolar lavage fluid (BALF) IgE levels were evaluated enzyme-linked immunosorbent assay (ELISA); and T-bet/GATA3 proteins were evaluated by Western blot. Our study demonstrated that Rb1 inhibited OVA-induced increases in RI and eosinophil counts; interleukin (IL)-4 was recovered, and IFN-γlevel increased in bronchoalveolar lavage fluid. Histological studies demonstrated that Rb1 substantially inhibited OVA-induced eosinophilia in lung tissue. Western blot studies demonstrated that Rb1 substantially inhibited GATA3 and increased T-bet. These findings suggest that Rb1 may effectively ameliorate the progression of asthma and could be used as a therapy for patients with allergic asthma.

Inflammation and its genesis in cystic fibrosis

The host inflammatory response in cystic fibrosis (CF) lung disease has long been recognized as a central pathological feature and an important therapeutic target. Indeed, many believe that bronchiectasis results largely from the oxidative and proteolytic damage comprised within an exuberant airway inflammatory response that is dominated by neutrophils. In this review, we address the longstanding argument of whether or not the inflammatory response is directly attributable to impairment of the cystic fibrosis transmembrane conductance regulator or only secondary to airway obstruction and chronic bacterial infection and challenge the importance of this distinction in the context of therapy. We also review the centrality of neutrophils in CF lung pathophysiology and highlight more recent data that suggest the importance of other cell types and signaling beyond NF-κB activation. We discuss how protease and redox imbalance are critical factors in CF airway inflammation and end by reviewing some of the more promising therapeutic approaches now under development.