(Press-News.org) In a study published in the June 19 online edition of the journal Nature, a scientific team led by researchers from the University of California, San Diego School of Medicine visually monitored the dynamic cellular events that take place when cardiac regeneration occurs in zebrafish after cardiac ventricular injury. Their findings provide evidence that various cell lines in the heart are more plastic, or capable of transformation into new cell types, than previously thought.
More importantly, the research reveals a novel potential source of cells for regenerating damaged heart muscle, according to principal investigator Neil Chi, MD, PhD, assistant professor of medicine in the Division of Cardiology and member of the Institute of Genomic Medicine at UC San Diego.
Heart failure remains the leading cause of death in the developed world, largely due to the inability of mammalian hearts to regenerate new cells and repair themselves. However, lower vertebrates such as zebrafish are capable of generating new ventricular heart muscle cells, or cardiomyocytes, that can replace the heart muscle lost through ischemia-induced infarcts – more commonly known in humans as heart attacks.
In this study, the scientists generated a genetic ablation system in zebrafish capable of targeted destruction of heart muscle, and then tracked both atrial and ventricular cardiomyocytes during injury using fluorescent proteins.
Using a genetic fate mapping technique – a method of comparing cells at various points of development in order to understand their cellular embryonic origin – the scientists revealed that cardiomyocytes in the heart's atrium can turn into ventricular cardiomyocyctes in a process called transdifferentiation. This transdifferentiation allows the atrial cells to regenerate and repair the ventricle, which is the chamber primarily affected in heart attacks.
First author Ruilin Zhang noted that such transdifferentiation was blocked when Notch signaling was inhibited, and subsequent studies will look at the Notch signaling pathway to understand the underlying mechanism at work.
"This is among the first studies to look at these specific cardiac lineages in detail to see how zebrafish are able to regenerate heart cells," said Chi, adding that their findings open a door to revealing how such regeneration might someday work to change the fate of human hearts.
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Additional contributors to the paper included Ruilin Zhang, Peidong Han, Hongbo Yang, Kunfu Ouyang, Derek Lee, Ju Chen,Yi-Fan Lin and Deborah Yelon, UC San Diego; Karen Ocorr, Sanford-Burnham Institue for Medical Research; Guson Kang and Didier Y. R. Stainier, UC San Francisco.
This work was supported in part by grants from the American Heart Association; the Packard Foundation; the National Institutes of Health (NIH) grants HL54737, OD007464 and HL104239; and NIH Heart, Lung, and Blood Institute.
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Philadelphia, Pa. (June 19, 2013) – The results of three important studies have been published in the June issue of Neurosurgery, official journal of the Congress of Neurological Surgeons. The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health.
One study indicates that continuous "machine learning" using artificial neural networks (ANNs) may improve the ability to predict survival in patients with advanced brain cancers. Another study in the June Neurosurgery supports increased use of stereotactic biopsy for obtaining samples of brainstem ...
(MINNEAPOLIS/ST. PAUL) June 19, 2013 – New research out of the University of Minnesota identifies significant risk factors for suicidal behavior in youth being bullied, but also identifies protective factors for the same group of children.
The article, "Suicidal Thinking and Behavior Among Youth Involved in Verbal and Social Bullying: Risk and Protective Factors" is being published in a special supplemental issue of the Journal of Adolescent Health. The supplement identifies bullying as a clear public health issue, calling for more preventative research and action.
Authors ...
Osteomyelitis – a debilitating bone infection most frequently caused by Staphylococcus aureus ("staph") bacteria – is particularly challenging to treat.
Now, Vanderbilt microbiologist Eric Skaar, Ph.D., MPH, and colleagues have identified a staph-killing compound that may be an effective treatment for osteomyelitis, and they have developed a new mouse model that will be useful for testing this compound and for generating additional therapeutic strategies.
James Cassat, M.D., Ph.D., a fellow in Pediatric Infectious Diseases who is interested in improving treatments for ...
WINSTON-SALEM, N.C. – June 19, 2013 – The role of dietary fructose in the development of obesity and fatty liver diseases remains controversial, with previous studies indicating that the problems resulted from fructose and a diet too high in calories.
However, a new study conducted in an animal model at Wake Forest Baptist Medical Center showed that fructose rapidly caused liver damage even without weight gain. The researchers found that over the six-week study period liver damage more than doubled in the animals fed a high-fructose diet as compared to those in the control ...
SYRACUSE, N.Y., June 19, 2013 –In the first effort to estimate the overall impact of a city's urban forest on concentrations of fine particulate pollution (particulate matter less than 2.5 microns, or PM2.5), a U.S. Forest Service and Davey Institute study found that urban trees and forests are saving an average of one life every year per city. In New York City, trees save an average of eight lives every year.
Fine particulate air pollution has serious health effects, including premature mortality, pulmonary inflammation, accelerated atherosclerosis, and altered cardiac ...
Advances in emergency medicine and trauma surgery have had a significant impact on survival of patients in the days immediately after major injuries, including burns. Patients who survive the immediate aftermath of their injuries now are at greatest risk from infections – particularly the overwhelming, life-threatening immune reaction known as sepsis – or from inflammation-induced multiorgan failure. Now, a device developed by Massachusetts General Hospital (MGH) investigators that measures the movement of key immune cells may help determine which patients are at greatest ...
People can plan strategic movements to several different targets at the same time, even when they see far fewer targets than are actually present, according to a new study published in Psychological Science, a journal of the Association for Psychological Science.
A team of researchers at the Brain and Mind Institute at the University of Western Ontario took advantage of a pictorial illusion — known as the "connectedness illusion" — that causes people to underestimate the number of targets they see.
When people act on these targets, however, they can rapidly plan accurate ...
A new process for making a three-dimensional microstructure that can be used in the analysis of cells could prove useful in counterterrorism measures and in water and food safety concerns.
The research, conducted by members of Virginia Tech's Microelectromechanical Systems Laboratory (MEMS) Laboratory in the Bradley Department of Electrical and Computer Engineering, is the focus of a recent article in the Institute of Electrical and Electronic Engineers' Journal of Microelectomechanical Systems.
In their engineering laboratory, the researchers developed a new microfabrication ...
When a new species emerges following adaptive changes to its local environment, the process of choosing a mate can help protect the new species' genetic identity and increase the likelihood of its survival. But of the many observable traits in a potential mate, which particular traits does a female tend to prefer?
A new study from the National Institute for Mathematical and Biological Synthesis finds that a female's mating decisions are largely based on traits that reflect fitness or those that help males perform well under the local ecological conditions.
Males' bright ...
EUGENE, Ore. -- (June 19, 2013) – A new study examining the brains of fruit flies reveals a novel stem cell mechanism that may help explain how neurons form in humans. A paper on the study by researchers at the University of Oregon appeared in the online version of the journal Nature in advance of the June 27 publication date.
"The question we confronted was 'How does a single kind of stem cell, like a neural stem cell, make all different kinds of neurons?'" said Chris Doe, a biology professor and co-author on the paper "Combinatorial temporal patterning in progenitors ...
