Scar tissue in the aging heart traced to one receptor
Cardiac fibrosis is one of the most dangerous consequences of heart disease: tissue loses its flexibility and the heart pumps less effectively. Researchers have now found a signalling pathway that drives this process through a receptor that has received little attention until now.
When the heart is damaged by a heart attack or prolonged high blood pressure, the body responds with scar formation. Fibroblasts (connective tissue cells in the heart) become active and produce large amounts of fibrous material. In the short term, this is protective. Over time, it makes heart tissue stiffer, worsening pump function and potentially leading to heart failure. Treatments that interrupt this process remain limited.
An overlooked receptor at the centre
The study, published in Science, identifies an atypical G protein-coupled receptor (a type of cell-surface receptor that relays signals from outside to inside the cell) as a central player in cardiac fibrosis. Atypical receptors in this class have been studied far less than their classical counterparts. Yet they appear to play a specific role in activating fibroblasts and driving connective tissue production in the heart.
Researchers showed that blocking this receptor in animal models reduced scar tissue formation without disrupting other cardiac functions. That matters because many earlier attempts to treat cardiac fibrosis caused unwanted side effects on heart rhythm or blood pressure. Whether this receptor works the same way in humans requires further investigation.
Relevance for the aging heart
Cardiac fibrosis does not only follow a heart attack; it also occurs with normal aging. Heart tissue gradually stiffens with age, contributing to the higher risk of heart failure in later life. From a longevity perspective, identifying a molecular brake on fibrosis that may also apply to age-related changes is an interesting lead, though one that requires further research before broader conclusions can be drawn.
Search terms to explore further: cardiac fibrosis G protein-coupled receptor | cardiac fibroblast activation signalling | myocardial stiffness aging