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

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:

More articles from Life Sciences:

nachricht Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München

nachricht Second research flight into zero gravity
21.10.2016 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Novel mechanisms of action discovered for the skin cancer medication Imiquimod

21.10.2016 | Life Sciences

Second research flight into zero gravity

21.10.2016 | Life Sciences

How Does Friendly Fire Happen in the Pancreas?

21.10.2016 | Life Sciences

More VideoLinks >>>