Cardiologists and molecular biologists at UT Southwestern, teaming up to study in mice how heart tissue regenerates, found that microRNAs – tiny strands that regulate gene expression – contribute to the heart’s ability to regenerate up to one week after birth.
Soon thereafter the heart loses the ability to regenerate. By determining the fundamental mechanisms that control the heart’s natural regenerative on-off switch, researchers have begun to better understand the No. 1 hurdle in cardiovascular research – the inability of the heart to regenerate following injury.
“For the first time since we began studying how cells respond to a heart attack, we now believe it is possible to activate a program of endogenous regeneration,” said Dr. Hesham Sadek, assistant professor of internal medicine in the division of cardiology, and the senior author of a study in the Proceedings of the National Academy of Sciences.
Each year, nearly 1 million people in the United States have a heart attack, while about 600,000 die of cardiovascular disease annually. Heart disease is the leading cause of death in both men and women, according to figures from the Centers for Disease Control and Prevention.
As researchers worldwide strive to find ways that help the human heart cope with myriad illnesses and injuries, scientists at UT Southwestern have focused their attention on the heart’s regenerative capabilities. In 2011, a team led by Dr. Eric Olson, chairman of molecular biology, and Dr. Sadek demonstrated that within three weeks of removing 15 percent of the newborn mouse heart, the organ was able to completely grow back the lost tissue, and as a result looked and functioned normally.
In the latest investigation, UTSW researchers found that hearts of young rodents mounted a robust regenerative response following myocardial infarction, but this restorative activity only occurs during the first week of life. They then discovered that a microRNA called miR-15 disables the regenerative capacity after one week, but when miR-15 is blocked, the regenerative process can be sustained much longer.
“It is a fresh perspective on an age-old problem,” said Dr. Olson, director of the Nancy B. and Jake L. Hamon Center for Basic Research in Cancer, and the Nearburg Family Center for Basic and Clinical Research in Pediatric Oncology who is a co-corresponding author of the PNAS study. “We’re encouraged by this initial finding because it provides us with a therapeutic opportunity to manipulate the heart’s regenerative potential.”
Further research will be needed to optimize the ways in which medical scientists, and eventually clinicians, may be able to control this regenerative process.
“This may well be the beginning of a new era in heart regeneration biology,” Dr. Sadek said. “Our research provides hope that reawakening the regenerative capacity of adult mammalian hearts is within reach.”
Other UT Southwestern investigators involved in the study are Dr. Beverly Rothermal, associate professor of internal medicine; Dr. Pradeep Mammen, assistant professor of internal medicine; Dr. Diana Canseco, postdoctoral researcher II of internal medicine; David Grinsfelder, research associate of internal medicine; and Brett Johnson, student research assistant of molecular biology. Former UTSW researchers involved are Dr. Ahmed Mahmoud, now at Harvard Medical Center; lead author Dr. Enzo Porrello, now at the University of Queensland in Australia; and Emma Simpson, research assistant in pathology.
MiRagen Therapeutics, a biotechnology company co-founded by Dr. Olson and others, is working to develop a new class of microRNA-based therapeutics to enhance heart repair by modulation of miR-15 and other microRNAs.
The study was funded by the National Institutes of Health, the American Heart Association, the National Heart Foundation of Australia, the Leducq Foundation, the Donald W. Reynolds Center for Clinical Cardiovascular Research, and the Robert A. Welch Foundation.This news release is available on our World Wide Web home page at
Russell Rian | Newswise
New photocatalyst speeds up the conversion of carbon dioxide into chemical resources
29.05.2017 | DGIST (Daegu Gyeongbuk Institute of Science and Technology)
Copper hydroxide nanoparticles provide protection against toxic oxygen radicals in cigarette smoke
29.05.2017 | Johannes Gutenberg-Universität Mainz
The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.
The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
29.05.2017 | Earth Sciences
29.05.2017 | Life Sciences
29.05.2017 | Physics and Astronomy