A Cleveland Clinic research team has demonstrated that an enzyme called arginase revs up cellular metabolism in asthma, a finding that sheds new light on the biological similarities between asthma and obesity while also suggesting potential new treatment strategies.
Led by Serpil Erzurum, M.D., a Cleveland Clinic pulmonologist, the research team found that the process of energy production – known as cellular respiration or aerobic metabolism – occurs to a greater degree than normal in the presence of asthma. This metabolic increase is caused by changes in a mitochondrial enzyme called arginase.
Using a mouse model of asthma, they showed that arginase activation and availability is enhanced, allowing the cells to produce more energy during cellular respiration. Interestingly, they found that the increase in metabolism suppressed inflammation in the lungs and protected asthmatic mice from developing more severe forms of the disease.
“Our results indicate that enhanced arginine metabolism may counteract inflammation and possibly offer protection for asthmatic patients,” Dr. Erzurum said. “It also supports mounting evidence that bioenergetic changes and inflammation underlie both asthma and obesity.”
Asthma and obesity have long been associated with each other, but a definitive biological link between the diseases has not yet been discovered. More studies are needed to clarify the exact mechanisms of arginase upregulation.
About 22 million Americans suffer from asthma, an inflammation of the airways in the lungs. It causes wheezing, coughing and shortness of breath and in some cases can lead to death. Exercise, allergies and airborne dust can set off asthma attacks.
The study’s findings are published in the current issue of The Journal of Clinical Investigation: http://www.jci.org/articles/view/82925
Dr. Erzurum, a pulmonologist and critical-care physician, is chair of the Department of Pathobiology at the Lerner Research Institute at Cleveland Clinic.