After a heart attack, researchers have created a novel approach that can mend and even regenerate heart muscle cells (or myocardial infarction).
Even though it has only been tried on mice thus far, if it is successful in humans, it may be able to save the lives of those who have had a heart attack.
The procedure makes use of a man-made messenger ribonucleic acid (mRNA). The body uses the DNA sequences that are produced by mRNA as a "blueprint" to assemble the proteins that make up and control our cells. Scientists can give various instructions to different biological processes by modifying the mRNA.
Here, two so-called mutant transcription factors—Stemin and YAP5SA—help the altered instructions encourage the replication of heart muscle cells (cardiomyocytes).
In essence, the goal is to make heart muscle cells, which have a very limited capacity for regeneration, behave more like stem cells, which the body can transform into a variety of other specialized cell types.
The difference made by the mRNA treatment after four weeks. (The Journal of Cardiovascular Aging)
According to scientist Robert Schwartz of the University of Houston in Texas, "no one has been able to accomplish this to this level and we think it might become a feasible cure for humans."
The cardiomyocytes we have when we die are mostly the same ones we've had from the first month of life since less than 1% of adult cardiac muscle cells can regenerate, which means heart attacks and heart disease can leave the heart in a chronically unstable state.
Stemin was found to activate stem cell-like qualities in the cardiomyocytes in trials conducted in tissue culture dishes and on live mice, whereas YAP5SA enhanced organ development and replication. The club has referred to the procedure as a "game-changer."
Myocyte nuclei replicated at least 15 times faster in the 24 hours following the injection of the mutant transcription factors Stemin and YAP5SA, according to an in vivo investigation using living mice with injured hearts.
The findings were astounding, according to Schwartz, when both transcription factors were put into infarcted adult mouse hearts.
Hearts were rebuilt to almost normal cardiac pumping performance with no scarring over the course of the next month, according to the laboratory's findings.
According to the researchers, the synthetic mRNA that was introduced to the cells quickly vanished, much as the mRNA created by human bodies. Compared to gene therapy procedures that cannot be readily stopped or eliminated once they have started, the new approach has this benefit.
The study team is confident, but it is still unclear if the method can be effectively applied to humans. Many more years of research will be needed to turn this into a medication that works.
More research is being done to better understand heart disease, heart damage, and how the body reacts to these conditions. Given that heart disease is now the biggest cause of mortality in the US, research into cardiovascular health continues to be a top concern for scientists (accounting for around a quarter of all deaths).
According to scientist Siyu Xiao from the University of Houston, "This is a significant work in heart regeneration, especially considering the clever method of employing mRNA to distribute Stemin and YAP5SA."
The research has been published in here and here in the Journal of Cardiovascular Aging.
