( Some mature brain cells can grow new ex...)3 proteins may play important role in nerve-cell repair

The research examined three related receptor proteins, called GPR3, GPR6 and GPR12, on nerve cells in the brains of rats.

When researchers increased the amount of the three proteins, the cells grew extensions that were up to three times longer than those on nerve cells with normal levels of the proteins, and the extensions grew four to eight times faster than in control cells.

"Our findings suggest that these three proteins could be important targets for treating stroke, brain and spinal cord injuries and also neurodegenerative diseases," says principal investigator Yoshinaga Saeki of the Ohio State University Medical Center.

The study is published in the April 6 issue of the Journal of Biological Chemistry.

Increased amounts of the proteins were associated with a significant rise in the level of an important signaling molecule inside the nerve cells called cAMP. This molecule plays a key role in regulating nerve-cell growth, differentiation and survival, and the regeneration of long parts of the cell called axons that carry the nerve impulses.

Levels of cAMP drop in mammalian nerve cells as they mature, and this is thought to explain, in part, why mature nerve cells cannot regenerate damaged axons.

"Our findings provide additional evidence that cAMP plays an important role in axon growth and suggest that these receptors are likely to play a major role in regulating cAMP production in nerve cells," says Saeki, an associate professor of neurological surgery and chief of Ohio State's Dardinger Laboratory for Neuro-oncology and Neurosciences.

In this study, first author Shigeru Tanaka, a postdoctoral fellow in Saeki's laboratory, and his colleagues used nerve cells obtained from the brain tissue of rats and mouse neuroblastoma cells growing in cult
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Source:Ohio State University