Navigation Links
Neurons get their neighbors to take out their trash
Date:6/19/2014

Biologists have long considered cells to function like self-cleaning ovens, chewing up and recycling their own worn out parts as needed. But a new study challenges that basic principle, showing that some nerve cells found in the eye pass off their old energy-producing factories to neighboring support cells to be "eaten." The find, which may bear on the roots of glaucoma, also has implications for Parkinson's, Alzheimer's, amyotrophic lateral sclerosis (ALS) and other diseases that involve a buildup of "garbage" in brain cells.

The study was led by Nicholas Marsh-Armstrong, Ph.D., a research scientist at the Kennedy Krieger Institute and an associate professor in the Johns Hopkins University School of Medicine's Solomon H. Snyder Department of Neuroscience, together with Mark H. Ellisman, Ph.D., a neuroscience professor at the University of California, San Diego. In a previous study, the two had seen hints that retinal ganglion cells, which transmit visual information from the eye to the brain, might be handing off bits of themselves to astrocytes, cells that surround and support the eye's signal-transmitting neurons. They appeared to pass them to astrocytes at the optic nerve head, the beginning of the long tendril that connects retinal ganglion cells from the eye to the brain. Specifically, they suspected that the neuronal bits being passed on were mitochondria, which are known as the powerhouses of the cell.

To find out whether this was really the case, Marsh-Armstrong's research group genetically modified mice so that they produced indicators that glowed in the presence of chewed up mitochondria. Ellisman's group then used cutting-edge electron microscopy to reconstruct 3-D images of what was happening at the optic nerve head. The researchers saw that astrocytes were, indeed, breaking down large numbers of mitochondria from neighboring retinal ganglion cells.

"This was a very surprising study for us, because the findings go against the common understanding that each cell takes care of its own trash," says Marsh-Armstrong. It is particularly interesting that the newly discovered process occurs at the optic nerve head, he notes, as that is the site thought to be at fault in glaucoma. He plans to investigate whether the mitochondria disposal process is relevant to this disease, the second leading cause of blindness worldwide.

But the implications of the results go beyond the optic nerve head, Marsh-Armstrong says, as a buildup of "garbage" inside cells causes neurodegenerative diseases such as Parkinson's, Alzheirmer's and ALS. "By showing that this type of alternative disposal happens, we've opened up the door for others to investigate whether similar processes might be happening with other cell types and cellular parts other than mitochondria," he says.


'/>"/>

Contact: Shawna Williams
shawna@jhmi.edu
410-955-8236
Johns Hopkins Medicine
Source:Eurekalert

Related biology news :

1. Research details how developing neurons sense a chemical cue
2. Neurons can use local stores for communication needs
3. Geniposide protects hippocampal neurons via the non-classical estrogen signaling pathway
4. Studies identify spinal cord neurons that control skilled limb movement
5. 7.0T NMR assesses changes in hippocampal neurons in animal models of Alzheimers disease
6. Short-term environmental enrichment exposure induces maturity of newborn neurons
7. Special function of nestin+ neurons in medial septum-diagonal band of Broca in adult rats
8. Light-activated neurons from stem cells restore function to paralyzed muscles
9. Who reprograms rat astrocytes into neurons?
10. Researchers generate new neurons in brains, spinal cords of living adult mammals
11. Research of zebrafish neurons may lead to understanding of birth defects like spina bifida
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/27/2016)... Research and Markets has announced the addition ... to their offering. The report ... to grow at a CAGR of 12.28% during the period 2016-2020. ... in-depth market analysis with inputs from industry experts. The report covers ... The report also includes a discussion of the key vendors operating ...
(Date:6/20/2016)... -- Securus Technologies, a leading provider of civil ... investigation, corrections and monitoring announced that after exhaustive ... the final acceptance by all three (3) Department ... (MAS) installed. Furthermore, Securus will have contracts for ... October, 2016. MAS distinguishes between legitimate wireless device ...
(Date:6/7/2016)... TORONTO , June 7, 2016  Syngrafii ... begun a business relationship that includes integrating Syngrafii,s ... pilot branch project. This collaboration will result in ... for the credit union, while maintaining existing document ... http://photos.prnewswire.com/prnh/20160606/375871LOGO ...
Breaking Biology News(10 mins):
(Date:12/5/2016)... NxGen MDx announced today that it brought its NxGen Informed ... been able to improve customer service through shortened turnaround times and at ... , CEO of NxGen MDx. ... A decrease in turnaround times by ... job opportunities at the Grand Rapid headquarters. The NxGen Informed ...
(Date:12/4/2016)... ... December 03, 2016 , ... ... studies. A microbiome impact grant award has been made to Dr. Renato Polimanti ... smoking and drinking on the oral microbiome. Grant proposals have been vetted by ...
(Date:12/2/2016)...  The Multiple Myeloma Research Foundation (MMRF) today announced ... SM —the largest and most comprehensive study driving new ... be presented at the 58 th American Society ... San Diego from December 3-6. The ... well as identify pathways and targets for new drug ...
(Date:12/2/2016)... ... December 01, 2016 , ... ... findings demonstrating the value of DNA microarray comparative genomic hybridization (array CGH) ... Antonio Breast Cancer Symposium. Using molecular test results from tumors with previously ...
Breaking Biology Technology: