How irritating: the role of TRPA1 in sensing cigarette smoke and aerogenic oxidants in the airways

Airway irritants cause a variety of lung pathologies. Two separate studies, the first recently reported in the JCI by Bessac et al. and the second reported by Andre et al. in the current issue of the JCI (see the related article beginning on page 2574), have identified irritants that activate transient receptor potential cation channel, subfamily A, member 1 (TRPA1) receptors in airway sensory neurons, resulting in neurogenic inflammation and respiratory hypersensitivity. The identification of TRPA1 activation by toxicants from cigarette smoke and polluted air, such as crotonaldehyde, acrolein, and oxidizing agents such as hydrogen peroxide, is an important finding. These two studies enhance our understanding of how pollution-and cigarette smoke can damage airway function and will hopefully pave the way for the development of rational alternative therapeutics for such airway injury.