Exosome therapy limits heart scarring after attack
After a heart attack, the heart heals poorly. Damaged tissue forms scar tissue, permanently weakening its pumping function. New research suggests that tiny vesicles derived from stem cells may be able to slow that process.
Researchers developed a therapy based on extracellular vesicles, also known as exosomes, small particles that cells secrete. These were derived from bone marrow stromal cells and tested in mice and pigs following an induced heart attack. In mice, left ventricular ejection fraction was better preserved and cardiac fibrosis, the formation of stiff scar tissue, was reduced.
Pigs and a new imaging tool
In a porcine model, which more closely approximates human heart size, the therapy was administered via the coronary artery. Results were again cardioprotective. In parallel, the researchers developed an imaging platform to track fibrotic activity in heart attack patients over time. Preliminary observations in patients suggest that myofibroblast activation, the cellular process responsible for scar tissue formation, persists for up to two months after the event.
That finding matters: if the scarring process remains active that long, there is a wider therapeutic window for intervention.
What this means for aging hearts
Cardiovascular disease is the leading cause of death in older adults. As we age, the heart recovers less effectively from damage. Therapies that limit scar formation and preserve pumping function are therefore relevant to the longevity agenda. The study, published in Cell Stem Cell, is preliminary. The step from animal models to clinical use in humans remains large, and no results from randomized trials in humans are yet available.
Even so, the combination of a therapeutic approach and a matched diagnostic imaging tool represents a notable step toward personalized cardiac care following heart attacks.
Search terms: extracellular vesicles cardiac fibrosis, myofibroblast heart remodeling, mesenchymal stromal cell exosome therapy