Medication used to treat asthma and pneumonia, can become ineffective, according to a recent study.

Researchers from the University of Manchester found that that cells lining the lung airways have their own body clock which is the time-keeper for lung inflammation -- both conditions cause swelling (inflammation) in the lungs. The drugs widely used to treat lung diseases work with the body clock.

The team also discovered that more severe lung inflammation happens as a result of the loss of the body clock working in these cells.

In the United Kingdom pneumonia, which is caused by an infection, affects around 1 in 1000 adults each year and is more serious for babies, young children, the elderly, smokers and those with an underlying health condition. More than 5 million people in the United Kingdom are affected by asthma and the National Health Service spends around £1 billion a year treating and caring for people with the disease.

And the team discovered that more severe lung inflammation happens as a result of the loss of the body clock working in these cells.

"We found a key molecule known as CXCL5 that facilitates lung inflammation which is a key regulator of how immune cells get into tissues. The loss of CXCL5 completely prevents the time of day regulation of lung inflammation which opens up new ways to treat lung diseases," researcher Andrew Loudon said in a statement.

During the study, researchers uncovered how glucocorticoid hormones from the adrenal gland are vital in controlling the level of inflammation in the cells lining the airway.

"This hormone works through the glucocorticoid receptor, a major regulator of gene expression. We wanted to find out therefore if glucocorticoid medicines, like prednisolone or dexamethasone would also show a time of day effect, and our research shows they do," researcher David Ray said in a statement.

The team concluded that the rhythm of the clock in the lining of the cells in the lungs is important for lung diseases like asthma, and chronic obstructive pulmonary disease.

"In this work we define a major circadian control on lung inflammation which affects responses to bacterial infection, or pneumonia," Loudon said. "We know that many lung diseases indeed show a strong time of day effect, including asthma, and deaths from pneumonia."

Researchers said this explains why it is hard to adjust to shift work. The body clock regulates sleep, but now has been discovered to also regulate our immune system.

The findings were recently published in Nature Medicine.