Traditional Chinese Medicine Shows Promise for Treating PAH, Study Reports

A compound in a plant that is used in traditional Chinese medicine lowered the lung blood pressure of rats with pulmonary arterial hypertension, a study shows

The compound, osthole, did this by decreasing levels of proteins associated with PAH, researchers said.

The study, “Global Proteomics Deciphered Novel-Function of Osthole Against Pulmonary Arterial Hypertension,” was published in the journal Scientific Reports.

Osthole is a component of a plant known as Angelica pubescens Maxim that has been used in traditional Chinese medicine for hundreds of years. It is supposed to promote blood circulation, relieve pain and offer other benefits.

Modern scientists believe it has anti-inflammatory activity and can make constricted blood vessels relax.

Its ability to treat PAH has been unclear, however, so a research time decided to do a study in rats to try to shed light on the matter.

PAH is a complex condition characterized by remodeling of lung arteries, high blood pressure, and thickening of the lower right heart chamber’s walls. This chamber, the right ventricle, pumps blood to the lungs.

A key finding of the study was that osthole reduced the rats’ mean lung blood pressure to  almost half what it was — to a level below what is considered consistent with PAH. Another finding was that it decreased enlargement of the right ventricle.

The results suggested that “osthole greatly reversed the increased pulmonary arterial pressure and right ventricular hypertrophy [enlargement] caused by PAH progression,” the researchers wrote.

In addition, the artery walls of rats treated with osthole were not as thick, “suggesting that osthole has the capability to inhibit pulmonary vascular remodeling,” the team wrote.

The researchers also checked protein levels in lung tissue samples taken from the rats. They found that the levels of 315 proteins had changed in rats with PAH, compared with controls.

Osthole restored 98 proteins to levels seen in the controls. The proteins are involved in such functions as metabolism, immune response, inflammation, and infection-related processes.

“Our findings demonstrated that global proteomics [the study of proteins] is a promising systems-biology approach for deciphering therapeutic actions and associated mechanisms of natural products derived from traditional Chinese medicine,” the team wrote. Osthole could be a candidate for a new drug to treat PAH, the team said.