Signals produced by intestinal microbes can make strokes and heart attacks more likely, new research has shown.
According to Cleveland Clinic, Ohio, scientist Stanley Hazen and his colleagues, a breakdown product released when certain groups of bowel bacteria digest food nutrients increases the "stickiness" of blood, making the formation of a fatal clot or thrombus in an artery more likely.
This promotes the formation of atheroma, the fatty deposits that furr up arteries, and it also increases the activity of platelets, cells fragments that float in the blood and play a critical role in the coagulation system.
Animals reared without any bowel bugs, or mice dosed long-term with broad-spectrum antibiotics, were not susceptible in the same way. But a "trans-poosion" of bowel bacteria from a normal mouse into one of these "germ free" counterparts restored the dietary risk from choline.
This enabled them to home in on eight common bacterial species that appear to do the bulk of the metabolism of choline into TMA that is then absorbed into the bloodstream, although how blood platelets sense and respond to TMA-O, or even why, isn't known yet.
As the team point out in their paper in Cell this week, the mainstay of current cardiac therapy is the use of anti-platelet drugs like aspirin, which prevent blood clots. While effective at saving lives, these drugs bring with them a significant risk of bleeding.
"Could manipulating gut microbes be a safer anti-platelet alternative?" they wonder.