Blood Protein Warns of Pulmonary Hypertension


A possible breakthrough in the diagnosis and treatment of pulmonary hypertension has been discovered by a Heart and Stroke Foundation researcher. It appears that elevated levels of a blood protein called PIM-1 may be an indicator of this life-threatening condition.

Pulmonary hypertension is treatable but incurable and deadly

Pulmonary hypertension is high blood pressure in the arteries that supply blood to the lungs. Over time, the blood vessels that transport blood from the heart to the lungs become narrow and hard, forcing the heart to work harder. Eventually the heart weakens, leading to heart failure. This potentially deadly condition can be treated but not cured.

Dr. Sebastien Bonnet, a professor at Laval University and a researcher at Centre Hospitalier Universitaire de Quebec, discovered what he calls “an early warning system in a protein called PIM-1.” Bonnet told the Canadian Cardiovascular Congress 2010 that the PIM-1 cells can be used as markers of pulmonary hypertension.

Bonnet found that blood samples taken from patients to measure PIM-1 revealed that the higher the PIM-1 levels, the more severe the pulmonary hypertension in patients. Therefore, “if there is a slight increase in PIM-1, we will know that something is going on,” he said.


Discovery of PIM-1 and elevated levels in people with pulmonary hypertension is important because the condition is often under diagnosed and not identified until the late stages. Early diagnosis is critical for treatment to be beneficial, while the prognosis for late stage disease is very poor.

There are two main types of pulmonary hypertension: one runs in families or develops for no apparent reason, and is rare; the other is associated with another condition, typically lung or heart disease. Symptoms include shortness of breath, extreme fatigue, and swelling in the feet and ankles. Treatments include medication for the heart or lung disease, oxygen therapy, and lung transplantation in some cases.

The National Heart Lung and Blood Institute states that the exact number of people who have pulmonary hypertension is not known. About two to three times more women than men develop the condition. It usually appears between the ages of 20 and 60, and risk factors include a family history of the condition, presence of a heart or lung disease, blood clots in the pulmonary arteries, or HIV infection, or use of certain diet drugs or cocaine.

Discovery of the blood protein PIM-1 in pulmonary hypertension is significant because it may lead to regular blood tests to look for levels of the protein and introduce ways to treat the disease. Bonnet notes that researchers have been able to block the PIM-1 protein. “We have found that using gene therapy to inhibit the inappropriate activation of this protein is a novel and effective therapy that can reverse the disease altogether.”

The Pulmonary Hypertension Association provides support and information for people with the condition and their families.

Heart & Stroke Foundation of Canada
National Heart Lung and Blood Institute
National Institutes of Health