Vanderbilt University researchers are coming to some surprising conclusions about abnormally low levels of oxygen in organs or tissues (hypoxia) and the effect on kidney disease. Hypoxia has been linked to inflammation in a number of ailments, including kidney disease, where it is also believed to cause kidney scarring or fibrosis. When hypoxia occurs, the body may adapt by producing hypoxia-inducible factors (HIF), transcription factors which signal a protective response.
The Vanderbilt scientists set out to discover how HIF behaves in kidney disease by experimenting with HIF-1 and HIF-2, HIF variants which are expressed in different cells of the kidney. They found that global activation of HIF suppressed inflammation and fibrosis in a mouse model of kidney injury; activation of HIF in the myeloid cells alone suppressed inflammation, but not fibrosis. Deleting HIF promoted inflammation. They also found that prolonged hypoxia suppressed the inflammatory response in healthy kidneys. The researchers hope to continue their studies to find out how HIF might be used to protect kidneys in chronic kidney disease.
Myeloid Cell-Derived Hypoxia-Inducible Factor Attenuates Inflammation in Unilateral Ureteral Obstruction-Induced Kidney Injury, The Journal of Immunology, April 6, 2012
Low Oxygen Could Protect Sick Kidneys, Vanderbilt University Medical Center, June 28, 2012