The study, that appears in the journal Science Translational Medicine, found that smoking activates certain genes and portions of the immune system, which in turn causes inflammation that leads to emphysema.
Emphysema is a long-term, progressive disease of the lungs that primarily causes shortness of breath. In people with emphysema, the tissues necessary to support the physical shape and function of the lungs are destroyed.
For their research, study author Dr Farrah Kheradmand and colleagues from the Baylor College of Medicine in the US, exposed mice to conditions that closely simulate how humans smoke. The mice developed emphysema within three to four months, and certain inflammatory cells and genes were key in that process.
‘It is a combination of little genes affected by an epigenetic factor,’ Kheradmand explained in a HealthDay News report. Epigenetic factors affect the way genes are expressed after DNA forms. One environmental epigenetic factor is cigarette smoke.
‘If you have enough genes affected by epigenetic factors strung together, it can tip you over into lung damage and emphysema,’ said Kheradmand. She added that the inflammation that drives emphysema could also drive cancer development, and noted that she and her colleagues have already started testing the hypothesis.
The HealthDay News report conclude that although studies involving animals can be useful, they often fail to produce similar results in humans, and therefore the current results cannot yet be translated as relevant in humans.
Sources: HealthDay News, EurekAlert!