Breathing easier about lung injury?

Patients with heart or lung problems, including premature babies, are given supplemental oxygen. But this intervention is sometimes too much of a good thing, because prolonged high concentrations of oxygen can cause hyperoxic acute lung injury, or HALI, in which the lungs’ capillaries become leaky.

The protein angiopoietin-2 (Ang2) destabilizes blood vessels, so Jack A. Elias, M.D., the Waldemar Von Zedtwitz Professor and chair of internal medicine, led a study to see whether Ang2 might contribute to HALI.

In the November 5, 2006 issue of Nature Medicine, Elias’s team reported high Ang2 levels and greater cell death in fluids and lung tissue taken from mice, adult humans and premature infants after exposure to high oxygen levels. But mice treated with RNA that suppressed Ang2 expression had far less damage, and mice bred to lack Ang2 lived significantly longer than their counterparts, raising the possibility that drugs designed to curb Ang2 could protect patients against HALI.

Vineet Bhandari, M.B.B.S., M.D., D.M., assistant professor of pediatrics and first author, says that the study was true bench-to-bedside research. “All the work was initially done on mice ... and then we showed its clinical relevance by documenting its presence in human patients with acute lung injury.”