Salbutamol improves markers of epithelial function in mice with chronic allergic pulmonary inflammation

We investigated the effects of salbutamol on the markers of epithelial function in a murine model of chronic allergic pulmonary inflammation by recording the ciliary beat frequency (CBF) and the transepithelial potential difference (PD) in vivo. Mice were sensitized and received four challenges of ovalbumin (OVA group) or 0.9% saline (control group). Forty-eight hours after the 4th inhalation, we observed eosinophilia in the bronchoalveolar lavage and epithelium remodeling with stored acid mucus in the OVA group (P < 0.001). No difference in the baseline CBF was noticed between the groups; however, the OVA group had a significantly lower baseline PD (P = 0.013). Salbutamol increased the CBF in all groups studied, and the dose response curve to salbutamol increased the PD in the OVA group from 10(-4) M to 10(-2) M. We suggest that salbutamol affects the CBF and the depth of the periciliary layer, which, in great part, determines the ability of the cilia to propel the mucus layer. This effect may have a positive impact on airway mucociliary transport in asthma and may have clinical implications. (C) 2011 Elsevier B.V. All rights reserved.

Oral tolerance attenuates airway inflammation and remodeling in a model of chronic pulmonary allergic inflammation

We investigated the effects of oral tolerance (OT) in controlling inflammatory response, hyperresponsiveness and airway remodeling in guinea pigs (GP) with chronic allergic inflammation. Animals received seven inhalations of ovalbumin (1-5 mg/mL-OVA group) or normal saline (NS group). OT was induced by offering ad libitum ovalbumin 2% in sterile drinking water starting with the 1st ovalbumin inhalation (OT1 group) or after the 4th (OT2 group). The induction of OT in sensitized animals decreased the elastance of respiratory system (Ers) response after both antigen and methacholine challenges, peribronchial edema formation, eosinophilic airway infiltration, eosinophilopoiesis, and airways collagen and elastic fiber content compared to OVA group (P < 0.05). The number of mononuclear cells and resistance of respiratory system (Rrs) responses after antigen and methacholine challenges were decreased only in OT2 group compared to OVA group (P < 0.05). Concluding, our results show that inducing OT attenuates airway remodeling as well as eosinophilic inflammation and respiratory system mechanics. (C) 2008 Elsevier B.V. All rights reserved.