University of Missouri researchers are leading the fight against one of the world's deadliest health threats: high blood pressure. Recently, they identified a protein that contributes to arterial stiffening and inflammation, opening the door to a new approach for preventing and treating the condition before it leads to heart attacks or strokes.
Camila Manrique-Acevedo, a professor at Mizzou's School of Medicine and investigator at the Roy Blunt NextGen Precision Health building, studies high blood pressure, also known as hypertension, which affects nearly half of U.S. adults and significantly increases the risk of serious cardiovascular events. By uncovering biological drivers of hypertension, her team is working to identify new treatment strategies for cardiovascular disease.
"High blood pressure increases the risk of cardiovascular disease tremendously, and while there are effective medications out there, many people still struggle to control their hypertension," Manrique-Acevedo said. "If we can better understand the underlying mechanisms contributing to hypertension in the first place, perhaps that can one day lead to more precise treatments with potentially fewer side effects."
Manrique-Acevedo collaborated with Guido Lastra, an associate professor in the School of Medicine, on the recent study. Lastra's lab studies a protein known as TG2, which is found in cells within blood vessels and has been linked to arterial stiffening. Because the protein is also present in immune cells that help regulate inflammation, Manrique-Acevedo and her team wanted to understand whether TG2 plays a role in the inflammation that contributes to high blood pressure.
For the study, which was supported by the U.S. Department of Veterans Affairs and led by Lastra, researchers compared different groups of mice. Some had normal levels of TG2 in their myeloid cells — a type of white blood cell that plays a key role in the body's immune system — while other groups of mice had TG2 removed from their myeloid cells.
When the mice with normal levels of TG2 were treated with angiotensin II, a hormone that helps regulate blood pressure, their blood pressure went up, their arteries became stiffer and there was more inflammation, as researchers expected.
However, when the mice that had TG2 removed were treated with angiotensin II, these increases in blood pressure, inflammation and arterial stiffness were not seen to the same degree as the mice with normal levels of TG2.
The findings suggest that blocking TG2 activity in myeloid cells could one day offer a new way to treat high blood pressure by reducing inflammation.
While hypertension is a complex disease with many contributing factors, Manrique-Acevedo said the findings represent an important step toward understanding the underlying biological processes that contribute to it.
Manrique-Acevedo, who also treats patients in her clinical roles with MU Health Care at University Hospital and as an endocrinologist at Harry S. Truman Memorial Veterans' Hospital, noted that the study focused on female mice. In the future, they could explore the effects of deleting TG2 in males.
"Tailoring treatments for those who can benefit the most is what precision medicine is all about," she said.
The study, "Myeloid transglutaminase 2 regulates Treg-Th17 balance in a female model of angiotensin II-induced hypertension and vascular stiffening," was published in the American Journal of Physiology. Coauthors on the study include Huma Naz and Emma Teixeiro.
