Vitamin A supplementation to prevent respiratory infection in the elderly

We are interested in developing methods for preserving mucociliary clearance in the aging lung in order to prevent respiratory infections. These infections occur more often and cause more death in older people. Lung health is highly dependent on the mucociliary clearance system where a protective layer of mucus lines the airways trapping inhaled bacteria, viruses, and toxins. Underneath the mucus, motile cilia beat synchronously within a thin periciliary liquid layer, clearing the mucus continuously from the lung and protecting it from infection and mucus obstruction. Studies show that the number of cilia in the airways and effectiveness of mucociliary clearance (MC) decreases substantially with age. We hypothesize that this effect can be reversed with oral vitamin A supplementation which promotes airway ciliation. We are interested in testing this hypothesis using measurements of mucus clearance and sampling of cells from the nasal airway.