Macrophages migrate through our arteries by eating fat to get it out. When full, however, they can constrict blood vessels and induce heart disease. Researchers from the UConn Health USA published a study in Nature Cardiovascular Research which shows how eliminating a protein can help ward off this problem. And prevent strokes and heart attacks in humans.
Our cleaning company
Macrophages are large white blood cells that function as a cleaning team that moves around our body, cleaning up dangerous debris. On the other hand, macrophage activity, as mentioned, can cause problems in people with atherosclerosis when fat deposits and inflammation develop in their blood vessels. They eat the excess fat within the artery walls, but that fat causes them to become foamy. And foamy macrophages tend to encourage inflammation in the arteries and sometimes break down plaques, releasing clots that can cause infarct, ictus or embolisms in other parts of the body.
The study on the protein against heart attacks and strokes
The researchers found that a protein called TRPM2, activated by inflammation, signals macrophages to start eating fat. Since inflammation of the blood vessels is one of the primary causes of atherosclerosis, TRPM2 activates widely, producing the chain reaction that leads to serious problems.
“TRPM2's mechanism of action amazed the team,” he says Lixia Yue, a cell biologist at UConn School of Medicine. "They form a real vicious circle that promotes the development of atherosclerosis."
Yue e Pengyu Zong, the first author of the article, demonstrated a way to stop the cycle, at least in mice. They eliminated TRPM2 from a mouse model with atherosclerosis: result? No apparent negative effects, but no more atherosclerosis. And now?
The next step
The team is looking to understand whether increased TRPM2 expression in monocytes (macrophage precursors) in the blood is linked to the severity of cardiovascular disease. If they discover a link, high levels of TRPM2 could be a risk indicator for heart attacks and strokes.
It could be the beginning of the end for two great human killers.
