We might be only steps away from the quick and effective regeneration of heart tissue in humans. New research involving the zebrafish, an organism that can repair damaged and missing tissue, provides more insight into the subject. The findings are published in the journal Development.
Since the heart is the most important organ (though some will argue it is the brain), its tissue regeneration is an important topic to be addressed as the incidence of heart diseases has been increasing, claiming more and more human lives.
The human cardiovascular system, as that of all mammals, is characterised by a restricted regenerative capacity. This is why researchers from MDI Biological Laboratory based in Maine wish to enhance our ability to repair and restore tissues with the aim of extending lifespan beyond the additional limits imposed by diseases and injuries. Assistant Professor Voot P. Yin has been looking to do so through the study of the zebrafish which is known for its incredible talent of regenerating almost any limb and organ, from the heart to bone and blood vessels in both form and function. The fish is able to regenerate damaged, or even missing, tissue of its heart in around 30 to 60 days. This sounds too good to be true, but it is not science-fiction, as explains Yin. Moreover, the skills of the fish are not restrained by its age, all the more reason to use it to delve deeper into the mechanisms governing tissue regeneration.
But, how would examining the zebrafish help humans? Yin explains that while the appearances of the two creatures are nothing alike, they share as much as 70% of genetic material; more importantly, they have the same genes that are behind the formation of new heart muscle. However, what demarks humans from the zebrafish is the regulation of the activity of the genes following injuries like heart attacks. But, fortunately, since humans have those very same genes, perhaps more research will show how to activate that level of repair in ourselves as well. Yin hopes to revive the dormant genes to do so.
Another finding of Yin’s includes the role of a microRNA called miR-101a. This functions as a central genetic regulator that triggers heart muscle cells to grow, and scar tissue to be removed. Yin has collectively termed the two processes the “yin and yang” of heart tissue regeneration: while scar tissue acts as a protective bandage, it also hinders the smooth beating of the heart in the long-term, and thus has to be extracted so that heart muscle tissue can be renewed.
This body of research is also meant to identify drugs to remove this scar tissue. They discovered an experimental drug called ZF143 that has been found to speed up the process of repairing damaged heart and limb tissue. Yin and his team look forward to identifying more drugs of this nature to reactivate and accelerate mechanisms involved in tissue healing and restoration.