Ouabain Modulates Airway Remodeling Caused by Th2-High Asthma in Mice

Ouabain is a hormone able to modulate the acute inflammatory process, including type 2 inflammation. In this study, ouabain effect on allergic asthma was evaluated. BALB/c mice were submitted to chronic airway allergic inflammation induced by an ovalbumin (OVA) protocol. The animals were treated with ouabain or standard drug, budesonide. The following parameters were evaluated: cell migration, cytokine profile, IgE levels, lung histological modifications and MAPK activation. At first, it was observed that ouabain reduced OVA-induced cell migration into the lung, observed by bronchoalveolar lavage fluid (BALF) cell counting and lung histological analysis (HE stain). Additionally, ouabain negatively modulated alarmins (IL-33 and TSLP), Th2 high cytokines levels (IL-1β and IL-4) and tissue remodeling markers such as TNF-α and TGF-β. Treatment with ouabain also reduced OVA-specific IgE titers in BALF and serum, respectively, when compared to the OVA group. Lung histological parameters, including collagen deposition and mucus production induced by OVA were also attenuated by ouabain treatment. Finally, our results showed that p38 mitogen-activated protein kinase (MAPK) signaling pathways were suppressed by ouabain in this model. All these parameters were reduced by budesonide, a steroidal anti-inflammatory standard drug. These data together suggest that, in addition to its acute anti-inflammatory action, ouabain is also able to modulate allergic asthma.