Disease linked to amino acid deficiency

USA Today (Society for the Advancement of Education), Oct, 2005

An amino acid deficiency in sickle cell anemia patients is the result of hemolysis, a process where red blood cells rupture and release their contents into the bloodstream, reports a study from Children's Hospital & Research Center, Oakland, Calif. Low availability of the amino acid arginine is associated with lung disease and death in adult sickle cell patients.

The study supports new therapeutic strategies aimed at increasing arginine levels either through nutritional supplements or by developing new drug therapies that disable the arginase enzyme that consumes arginine.

"Lower amino acid ratios, which indicate low arginine availability, were found in patients who had more severe pulmonary hypertension, a condition involving high blood pressure in arteries carrying blood from the heart to small vessels in the lungs," points out Claudia Morris, an Emergency Department physician. "This incurable condition is the leading cause of death in adults with sickle cell disease."

The findings also highlight important new warning signs that may predict the severity of the disease and could be useful in identifying adult patients at risk for early death through a simple blood test that measures amino acid levels.

"With this new finding and continued research, we hope to increase our understanding of the development of pulmonary hypertension not only in sickle cell disease, but in thalassemia (Cooley's anemia) and other inherited anemias," concludes Elizabeth G. Nabel, director of the National Heart, Lung, and Blood Institute, Bethesda, Md.