"Magic" medicine for myocardial infarction

Recently, a research team composed of scientists from Harvard University, Massachusetts General Hospital and other units in the United States synthesized a modified messenger RNA (mRNA), which was injected into the myocardium of the mouse model of myocardial infarction, and could command the heart stem cells that should have formed scar tissue to develop into cardiovascular cells, promoting the recovery of the injured heart of the mouse, and taking an important step in the treatment of heart disease 。 Relevant papers were published in the recently published Nature Biotechnology "This is the beginning, which means that people can use the heart as a 'factory' to produce growth factors that act on certain types of cardiovascular stem cells And it's possible to produce new heart 'parts' without injecting any foreign cells into the heart " Kenneth Zien, head of the study, Professor of stem cell and regenerative biology at Harvard University and Karolinska Institute in Sweden, said Not long ago, Zien's laboratory found that there is a growth factor VEGF-A (vascular endothelial growth factor-A) in human heart blood vessels, which can also act as a switch, so that cardiac stem cells do not develop into cardiomyocytes and become coronary vessels above the heart On this basis, they synthesized a modified mRNA encoding VEGF-A and injected it into mouse cardiomyocytes The purpose of modifying mRNA is to make them avoid the normal defense system of the body Unmodified mRNA will be treated as a virus invader, rejected and decomposed They found that cardiomyocytes produced a wave of vegf-a It is very important to control the expression of VEGF-A in cardiac myocytes, so that VEGF-A can be put into the exact site of cardiac progenitor cells The experimental results showed that within 48 hours after the heart attack, a certain amount of artificially modified mRNA was injected into the myocardial infarction site, resulting in the expansion and directional differentiation of cardiac progenitor cells Cardiac stem cells no longer form fibrotic scar tissue, but form cardiovascular tissue, which significantly improves the cardiac function and improves the long-term survival rate of experimental mice "With just one dose of chemicals and no more injections of any other cells into the heart, this result is very close to the clinical study of regenerative cardiovascular tissue." The research is still in its early stages, with mice as models, and they plan to experiment with other animals, said Zien.