Mice exposed to cigarette smoke on daily basis avoided lung damage thanks to an experimental drug, raising the hope for a treatment in humans, US researchers reported in the online Dec. 22 Proceedings of the National Academy of Sciences.

 

The chemical, known as CDDO-Im, helped activate a master gene called Nrf2 that bolsters the lung’s ability to fight off chronic obstructive pulmonary disease, or COPD, a condition that includes emphysema, chronic bronchitis and some types of serious chronic asthma. CDDO-Im is a synthetic compound derived from oleanolic acid, a substance found in plants.

 

COPD is the fourth leading cause of death in the United States and there are no effective treatments. The condition is most commonly linked to smoking, but environmental factors such as pollution also play a role. Worldwide, the disease affects as many as 210 million people.

 

For the study, lead researcher Shyam Biswal, an associate professor at the Johns Hopkins Bloomberg School of Public Health in Baltimore, and his team exposed mice to cigarette smoke for six months to stimulate the lung damage seen in emphysema. Half the mice were treated with CDDO-Im while the other animals were not.

 

The mice treated with CDDO-Im did not develop heart and lung damage while their untreated counterparts did, the researchers found.

The findings provide hope that strategies aimed at targeting the Nrf2 pathway might be effective in inhibiting the development of emphysema, Dr. Biswal said.

 

“The Nrf2 pathway is the major antioxidant and detoxifying response in the lungs. Therapies targeting this pathway need to be developed and tested in patients,” said Biswal.