Stem Cell Regulator Could Hold Key to Staving Off Age-related Brain Changes

January 30, 2004

Stem Cell Regulator Could Hold Key to Staving Off Age-related Brain Changes

January 30, 2004

La Jolla, CA – A brain-specific genetic switch protein known as a receptor has been found to control the fate of adult stem cells in the brain, according to a Salk Institute study.

The findings, published in the Jan. 1 issue of Nature, suggest a way to prevent the learning and memory declines that occur during the aging process, as well as possible ways to treat neurodegenerative diseases and brain injury. The research also shows for the first time how adult brain stem cells begin their transformation into specialized cells.

Professors 罗纳德·埃文斯 和 弗雷德·H·盖奇 and their colleagues discovered that the receptor, called TLX, is needed to maintain proliferating stem cells in the brains of adult mice. Defects in the activity of TLX in mice result in violent and aggressive behavior that is often seen in neurodegenerative diseases and brain injury. Most important, re-introducing normal TLX into cells derived from mice with defective TLX restored their ability to behave as adult neural stem cells.

“TLX is present in the developing brain, but isn’t essential for early development,” said Gage. “It is surprisingly crucial for the function of adult nerve cells. Since this function declines with age, especially in areas of the brain important for learning and memory, TLX may be a target for protecting against age-related changes associated with cognitive decline.”

The researchers found that stem cells that have the TLX receptor could proliferate and differentiate into any of the variety of cells found in the adult brain. But without the receptor, none of the cells could grow, resulting in dramatic behavioral changes in the mice. These changes were reversed and cells were again able to proliferate when the scientists reintroduced TLX.

Gage is known for his earlier finding that the brain can regenerate nerve cells in adulthood, which lead to the discovery of adult stem cells in the brain. Since that discovery, researchers have been trying to find out exactly how the stem cells develop into working parts of the nervous system.

“If we can learn how to control the switch we might be able to stimulate the formation of new brain cells and restore or preserve learning and memory. With this switch in hand we will begin looking for drugs that might regulate its activity to stimulate brain function,” said Evans.

索尔克生物研究所（Salk Institute for Biological Studies）位于加利福尼亚州拉霍亚，是一个独立的非营利组织，致力于生命科学的基础发现、改善人类健康和条件，以及培养未来几代研究人员。乔纳斯·索尔克医学博士于1960年创立了该研究所，获得了圣地亚哥市政府赠送的土地以及“March of Dimes Birth Defects Foundation”（足迹慈善母婴健康基金会）的财政支持。.