A form of vitamin A could one day provide the basis for a cure for the smoking disease emphysema.
Smoking can cause emphysema
British researchers have found that retinoic acid, a derivative of vitamin A, can cure the disease in mice.
Writing in the European Respiratory Journal, they said it reverses damage done to tiny air sacs in the lungs.
There is currently no cure for emphysema. The disease causes progressive damage to the lungs and can eventually kill.
Emphysema usually affects older people. It is generally the result of long-term damage to the lungs, such as a lifetime of smoking. It can also affect people working in certain industries such as mining.
The disease can start as mild breathlessness. However, over time it can leave sufferers struggling to breathe and reliant on oxygen.
It occurs when the tiny air sacs in the lungs called alveoli, through which oxygen is absorbed into the bloodstream, lose their natural elasticity.
This means spent air is pushed back out into the lungs. The lungs feel overfull and it is a struggle for sufferers to push air in and out.
This eventually means that the body is not getting enough oxygen, leading to fatigue and weight loss.
Scientists believe that if they can return the tiny air sacs in the lungs to their former healthy state they can cure the disease.
This latest study by Professor Malcolm Maden and colleagues at the Medical Research Council's Centre for Developmental Neurobiology at King's College London raises hopes that a cure can one day be found.
The researchers bred mice with all the hallmarks of emphysema. The mice had been given a chemical soon after birth, which prevented the tiny air sacs in the lungs from developing properly.
By the time these mice were adults they had serious breathing problems and their lungs were unable to exchange gases effectively.
When these mice were given retinoic acid, the number and size of the tiny air sacs in the lungs returned to normal. Their lungs exchanged gases more effectively and they were able to breathe more easily.
The researchers believe that retinoic acid triggers key genes into action, enabling the tiny air sacs to recover.
While further studies are needed, this research raises hopes that retinoic acid could form the basis of a cure for emphysema.
Professor Maden said it could also provide the basis for a treatment for the severe lung disease COPD or chronic obstructive pulmonary disease.
"This would be quite significant," he told BBC News Online. "Incidence of emphysema and COPD are rocketing world-wide.
"This is a relatively simple compound to take. It is already used to treat severe acne.
"Being able to cure these conditions would be quite significant."