Global warming linked to an increased risk of airways infection

In a recent, cross -institutional study, researchers report that healthy human respiratory tract run a higher risk of dehydration and inflammation when exposing to dry air, a occurrence that is expected to increase as a result of global warming. Inflammation in human respiratory tract is associated with disorders such as asthma, allergic rhinitis and chronic cough.

Researchers say that as the atmosphere of the earth warms up, with relative humidity that usually remains the same, a characteristic of the atmosphere called vapor pressure shortage (VPD) increases rapidly. VPD is a measure of how “thirst” can be for water air. The higher VPD, the greater the evaporation speed of water, so drying out planetary ecosystems.

Based on mathematical predictions and experiments, researchers now explain that higher VPD can dry out the upper airways and activate the inflammatory and immune response of the body. In the full report, published March 17 in Communication earth and surroundingsThey also say that such a dehydration and inflammation can be exacerbated by the breathing of the mouth (the speeds of which also increase) and more exposure to air conditioning and heated indoor air.

“Air dryness is just as crucial for air quality as aerial waste, and managing the hydration of our airways is just as essential as the management of their cleanliness,” says main author David Edwards, deputy professor of medicine at Johns Hopkins University School of Medicine. “Our findings suggest that all the mucous membrane that is exposed to the atmosphere, including ocular mucous membrane, is at risk of dehydrating atmospheres.”

Edwards and the team first looked at whether perspiration, a water loss that occurs in plants, prevents in -mucus of upper airways exposed to dry air environments. High perspiration percentages have proven to cause harmful compression for cells in the leaves of plants, threatening the survival of plants. The team also tried to see whether such a compression took place in cells of the upper respiratory tract.

Researchers exposed cultures of human cells that are discussed along the upper respiratory tract, known as human bronchial epithelium, to dry the air. After exposure, the cells were evaluated on mucus thickness and inflammatory reactions. Cells experienced periods of dry air (with a high VPD) showed thinner mucus and high concentrations of cytokines, or proteins that indicate cell inflammation. These results correspond to theoretical predictions that mucous thunner can be taken in dry air environments and can produce sufficient cellular compression to activate inflammation.

The team also confirmed that inflammatory mucous transparation occurs during normal, relaxed breathing (also called tidal breathing) in an animal model. Researchers exposed healthy mice and mice with already existing airway dryness, which is common in chronic airway disorders, on a week of intermittent dry air. Mice with this existing dehydration showed immune cells in their lungs, indicating a high inflammatory response, while all the mice that were only exposed to moist air did not do so.

Based on a climate model research that the team has also conducted, they predict that the majority of America will run an increased risk of respiratory infection through the second half of the century due to higher temperatures and drier air.

Researchers concluded their work by saying that these results have consequences for other physiological mechanisms in the body, namely dry eyes and the movement of water in mucus lining in the eye.

“This manuscript is a game change for medicine, because human mucous membrane dehydration is currently a critical threat to human health, which will only increase as the global warming continues,” says research coo author Justin Hanes, Ph.D., the Lewis J. Ort Hopkin Medicine. “Without a solution, human mucous membrane will become drier over the years, leading to increased chronic inflammation and associated disorders.”

“Insight into how our airways dry out on dry air exposure can help us avoid or reverse the inflammatory impact of dehydration through effective behavioral changes and preventive or therapeutic interventions,” says Edwards.

Employees and authors of this research are Aurélie Edwards, Dan Li and Linying Wang of Boston University; Kian Fan Chung from Imperial College London; Deen Bhatta and Andreas Bilstein from Sensory Cloud Inc.; Indika Endirisinghe and Britt Burton Freeman from Illinois Institute of Technology; and Mark Gutay, Alessandra Livraghi-Butrico and Brian Button from University of North Carolina. The authors do not report an interest conflict.