Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Major Discovery Helps Explain How the Adult Brain Cleans out Dead Brain Cells and Produces New Ones

12.08.2011
Adult brains generate thousands of new brain cells called neurons each day; however only a small fraction of them survive. The rest die and are consumed by scavenger cells called phagocytes. Until now, scientists have not fully understood how this process works, which phagocytes are unique in the brain, and how the removal of dead neurons influences the production of new neurons.

In humans, neurogenesis, or the formation of new neurons, largely ceases in most areas of the brain during adulthood. However, in two brain areas there is strong evidence that substantial numbers of new neurons are naturally generated (in the hippocampus, which is involved in memory forming, organizing and storing, and the olfactory bulb, involved in the perception of odors).

UVA Health System researchers have made a pivotal discovery in understanding this complicated process, and their findings could one day help scientists devise novel therapies to promote neurogenesis in the adult brain and re-establish its function in patients suffering from depression, post-traumatic stress disorder, and other mental disorders, in which adult neurogenesis is impaired .

The findings appear in a study published online July 31, 2011 in the journal Nature Cell Biology and led by two UVA researchers -- Jonathan Kipnis, PhD, associate professor of neuroscience, and Kodi S. Ravichandran, PhD, chair of the UVA Department of Microbiology and director of the UVA Center for Cell Clearance. Zhenjie Lu, PhD, is the first author on this work and was instrumental in combining the methodologies in the Kipnis lab (which focuses on basic mechanisms underlying neurological disorders) and the Ravichandran lab (which focuses on cell clearance) to address adult neurogenesis through a combination of in vivo studies in normal and genetically altered mice, and ex vivo studies using neuronal cultures.

Through their research, UVA scientists discovered that certain types of progenitor cells, called the doublecortin (DCX)-positive neuronal progenitors (or “newborn neurons”), serve a dual role in the regulation of production and elimination of new brain cells. Progenitor cells generally act as a repair system for the body, replenishing special cells and maintaining blood, skin and intestinal tissues. This new discovery points to the ability of these cells to clean each other out, which ultimately benefits the regeneration process.

“Our study provides the first evidence that DCX+ cells, in addition to serving their function as neuronal precursors in the brain, also function as phagocytes [scavenger cells] by clearing out their dead brethren -- and that this process is required to maintain continuous generation of new neurons in the brain,” says Kipnis.

“These findings raise the possibility that this newly discovered process could be manipulated to rejuvenate the brain by regulating the addition of new neurons,” says Ravichandran.

This discovery, Kipnis adds, also could shed new light on our understanding of how the process of adult neurogenesis is regulated in the healthy brain, and in turn provide insights on diseased brains, where adult neurogenesis is severely impaired.

“The birth and death of new neurons in the adult brain have been implicated in ongoing learning and memory,” says Kevin Lee, PhD, chair of the Department of Neuroscience and professor of neurological surgery. “The findings by Kipnis, Ravichandran, Lu and associates are fascinating, because they describe a novel process regulating the production and removal of adult-born neurons. This represents an important step toward identifying mechanisms that might be manipulated to control the number of new neurons in the adult brain. Regulating new adult neurons in this manner could open a novel avenue for modifying basic cognitive functions, including learning.”

Sally H. Jones | Newswise Science News
Further information:
http://www.virginia.edu

More articles from Life Sciences:

nachricht Climate Impact Research in Hannover: Small Plants against Large Waves
17.08.2018 | Leibniz Universität Hannover

nachricht First transcription atlas of all wheat genes expands prospects for research and cultivation
17.08.2018 | Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>