A common virus affecting 60 to 99 percent of adults worldwide can be a major cause of high blood pressure, finds a new study.
The research team from Beth Israel Deaconess Medical Center (BIDMC) showed that when combined with other risk factors for heart disease, the cytomegalovirus (CMV), can lead to the development of atherosclerosis, or hardening of the arteries.
"CMV infects humans all over the world," said co-senior author Dr Clyde Crumpacker, an investigator in the Division of Infectious Diseases at BIDMC and Professor of Medicine at Harvard Medical School.
"This new discovery may eventually provide doctors with a whole new approach to treating hypertension, with anti-viral therapies or vaccines becoming part of the prescription," Crumpacker added.
CMV affects all age groups and is the source of congenital infection, mononucleosis, and severe infection in transplant patients.
In the study using mouse models, the scientists examined four groups of laboratory mice.
Two groups of animals were fed a standard diet and two groups were fed a high cholesterol diet. After a period of four weeks, one standard diet mouse group and one high-cholesterol diet mouse group were infected with the CMV virus.
They found that CMV-infected mice had increased blood pressure compared with the uninfected group.
Moreover, 30 percent of the CMV-infected mice that were fed a high-cholesterol diet not only exhibited increased blood pressure, but also showed signs of having developed atherosclerosis.
"This strongly suggests that the CMV infection and the high-cholesterol diet might be working together to cause atherosclerosis," said Crumpacker.
A second analysis found that infection of a mouse kidney cell line with murine CMV led to an increase in expression of the renin enzyme, which has been known to activate the renin-angiotensin system and lead to high blood pressure.