Ornamental Plant Extract May Help Combat Asthma

An active pharmaceutical ingredient extracted from the leaves of coralberry - a popular ornamental plant - may help combat asthma, a study claims.

The coralberry is no outstanding horticultural beauty during most of the year. However, in the winter months it forms striking, bright red berries, which make it a popular ornamental plant during the Christmas holidays.

The substance called Ardisia crenata found in its leaves could be suitable as a medication against certain diseases. Researchers at the University of Bonn in Germany found that Ardisia crenata is effective at preventing the bronchial muscles from contracting in mice.

Asthmatics regularly suffer from these pronounced contractions, preventing adequate ventilation of the lungs. The resulting shortness of breath can be life threatening. The new compound relieves these spasms, and has a more prolonged action than the most common asthma drug, salbutamol.

"However, we have so far only tested the substance in asthmatic mice," said Daniela Wenzel, from the University of Bonn. Scientists isolates and characterised the active pharmaceutical substance from the leaves of the coralberry.

"This compound inhibits critical signalling molecules in our cells, the Gq proteins," said Wenzel. Gq proteins exert key functions in many processes in the body, including control of the airway tone.

Normally, the interaction of signalling pathways induces narrowing of the airways. Inhibition of individual signalling pathways can reduce the contraction of the respiratory tract.

However, this does not make it possible to completely prevent such contractions in patients with severe asthma. The contracting signals converge on Gq proteins and trigger airway spasm events.

"When we inhibit the activation of Gq proteins with FR900359, we achieve a much greater effect," said Michaela Matthey from the University of Bonn.

This worked exceptionally well in asthmatic mice, researchers said. "We were able to prevent the animals from reacting to allergens such as house dust mites with a narrowing of the bronchia," said Wenzel.

There were few side effects, as the active pharmaceutical ingredient was administered via inhalation to the respiratory tract, and thus only reached the systemic circulation in small quantities.

However, it is not known whether the substance is suitable for use in people. Although the scientists have already demonstrated that human bronchial muscle cells and isolated human airways react in a similarly in the lag, further tests are required prior to human use.

(With Agency Inputs)