Task: Explanation
Input (English): Paragraph: A right lateral view chest x-ray of a healthy lung is seen in an undated handout photo. REUTERS/DCD/Dr. Thomas Hooten/Handout Chronic obstructive pulmonary disease, or COPD, is the fourth-leading cause of death in the United States and the world and is on the rise. There is no cure. The researchers found that a master gene called NRF2, which turns on other genes involved in protecting the lungs from pollution and cigarette smoke, was not working properly in smokers with advanced COPD, which affects 210 million people worldwide. And they said a compound found in broccoli might help correct this problem. “This work clearly demonstrates that a decline in our antioxidant system is involved in progression of COPD, which could also be the cause for other environmental disease,” Shyam Biswal of Johns Hopkins School of Medicine said in a statement. There are no treatments for COPD, a condition that includes emphysema, chronic bronchitis and some types of serious chronic asthma. Smoking is by far the leading cause of COPD, but environmental factors such as pollution play a role. In earlier studies, Biswal found that mice with poorly working NRF2 genes developed severe emphysema. His current study in the American Journal of Respiratory and Critical Care Medicine looked at tissue samples of smokers with COPD and those without it. They found that the lungs of people with COPD had decreased levels of antioxidants that were regulated by the NRF2 gene. The sicker the patients, the lower the levels they found. But they also found that sulforaphane, a compound that occurs naturally in broccoli and wasabi, was able to restore the function of the NRF2 gene in human tissue. “These are the keys we are looking for in terms of having a more specific intervention,” Dr. John Heffner, past president of the American Thoracic Society, said in a telephone interview. “If we can discover the primary triggers that induce lung damage in smokers we will be able to slow the progression of this highly lethal condition,” Heffner said. He said the study, which he was not involved in, pointed to a genetic switch that turns off the body’s defenses against cigarette smoke and leads to lung damage. “Compounds that target that switch may be able to turn it back on to prevent the progression of COPD.”   He said it was too early to suggest eating broccoli would cure COPD. Other clinical trials of antioxidants have failed to show a benefit. “We are hoping to initiate human trials with these more specific compounds that target what has been shown to be the most important antioxidant system,” he said. Claim: Gene switch malfunctioning in chronic lung disease.
Output (English): Smokers who have chronic lung disease are much more likely to have a poorly working antioxidant defense system than other smokers, a finding that may lead to new treatments, U.S. researchers said on Friday.