Sweet talk: insights into the nature and importance of glucose transport in lung epithelium
JP Garnett, EH Baker, DL Baines - European Respiratory …, 2012 - Eur Respiratory Soc
JP Garnett, EH Baker, DL Baines
European Respiratory Journal, 2012•Eur Respiratory SocFor over 50 years, glucose has been recognised to cross the lung epithelial barrier and be
transported by lung epithelial cells. However, until recently, research into these processes
focused on their effects on lung liquid volume. Here, we consider a newly identified role for
pulmonary glucose transport in maintaining low airway surface liquid (ASL) glucose
concentrations and propose that this contributes to lung defence against infection. Glucose
diffuses into ASL via paracellular pathways at a rate determined by paracellular permeability …
transported by lung epithelial cells. However, until recently, research into these processes
focused on their effects on lung liquid volume. Here, we consider a newly identified role for
pulmonary glucose transport in maintaining low airway surface liquid (ASL) glucose
concentrations and propose that this contributes to lung defence against infection. Glucose
diffuses into ASL via paracellular pathways at a rate determined by paracellular permeability …
For over 50 years, glucose has been recognised to cross the lung epithelial barrier and be transported by lung epithelial cells. However, until recently, research into these processes focused on their effects on lung liquid volume. Here, we consider a newly identified role for pulmonary glucose transport in maintaining low airway surface liquid (ASL) glucose concentrations and propose that this contributes to lung defence against infection.
Glucose diffuses into ASL via paracellular pathways at a rate determined by paracellular permeability and the transepithelial glucose gradient. Glucose is removed from ASL in proximal airways via facilitative glucose transporters, down a concentration gradient generated by intracellular glucose metabolism. In the distal lung, glucose transport via sodium-coupled glucose transporters predominates. These processes vary between species but universally maintain ASL glucose at 3–20-fold lower concentrations than plasma.
ASL glucose concentrations are increased in respiratory disease and by hyperglycaemia. Elevated ASL glucose in intensive care patients was associated with increased Staphylococcus aureus infection. Diabetic patients with and without chronic lung disease are at increased risk of respiratory infection. Understanding of mechanisms underlying lung glucose homeostasis could identify new therapeutic targets for control of ASL glucose and prevention and treatment of lung infection.
European Respiratory Society