BALTIMORE, Sept. 15 (UPI) -- Eating broccoli helps patients with chronic obstructive pulmonary disease, researchers at the Johns Hopkins Medical School in Baltimore said.
Principle investigator Shyam Biswal said a decrease in lung concentrations of NRF2-dependent antioxidants -- a key components of the lung's defense system against inflammatory injury -- is linked to the severity of COPD in smokers. Broccoli is known to contain a compound that prevents the degradation of NFRP.
Researchers examined tissue samples from the lungs of smokers with and without COPD to determine if there were differences in measured levels of NRF2 expression and the level of its biochemical regulators, including KEAP1, which inhibits NRF2, and DJ-1, which stabilizes it.
Biswal had previously shown that disruption in NRF2 expression in mice exposed to cigarette smoke caused early onset of severe emphysema.
When compared to non-COPD lungs, the lungs of patients with COPD showed markedly decreased levels of NRF2-dependent antioxidants, increased oxidative stress markers, a significant decrease in NRF2 protein with no change in NRF2 mRNA levels -- indicating that it was expressed, but subsequently degraded.
The findings are published in the American Journal of Respiratory and Critical Care Medicine.