It’s said that there is no medicine for a broken heart, but what if the ability to heal were already within us? Zebrafish have hearts that can regenerate themselves, yet mammalian hearts (including those of mice) do not have the same capacity. However, a new study published in June of 2017 in Nature identified Agrin, a protein present in the neonatal extracellular matrix (a collection of molecules that provides structural and biochemical support to nearby cells), as having the potential for regenerating injured mouse hearts.
When we are in the womb, we can regenerate tissue; however, once we pass the first week of life we lose that ability. Therefore, researchers considered what potential Agrin poses in living organisms. To test their hypothesis, they considered what a single intramyocardial injection of Agrin could achieve in juvenile and adult mice with damaged hearts.
Researchers noted four days after injection, the damaged areas of the heart were similar to those of control group, with no significant effect on heart function. Fourteen days post-injection, scar tissue was reduced, by day thirty-five significantly reduced. In contrast to the untreated mice, Agrin-treated mice also showed protection from dilated cardiomyopathy (thinning of heart wall), which is often a complication of heart damage.
Researchers also found that Agrin had other beneficial effects such as promoting the development of new blood vessels. Compared to current cardiac regenerative strategies, Agrin shows great potential as a safe and effective technique for repairing damaged hearts. The answer could have been within us the whole time.