Washington: Specialized nerve or brain cells called neurons can rebuild themselves after an injury, says a new study based on fruit flies. These results potentially open up newer ways of treating traumatic nerve damage or neuro-degenerative disease.

The discovery of an injured neuron's remarkable ability to re-programme itself was made by Michelle Stone, Melissa Rolls and colleagues at Penn State University (PSU). The scientists said the re-programming was particularly surprising because once formed, neurons normally are relatively stable.

They injured the neuron in the fruit fly (Drosophila melanogaster) brain by using a laser to cut off the entire axon, the long, slender part that sends the neuron's signals to other brain cells.

Following the injury, the dendrites, parts of the neuron that receives signals from other brain cells, reshuffled their internal support structures, or cytoskeletons. Eventually one of the dendrites switched its polarity and grew into a permanent replacement for the damaged axon.

Polarity refers to the differentiation of cell into parts having opposed or contrasted properties. The polarity of the microtubules (basic units of the cytoskeleton) in axons and dendrites differ, reflecting the different roles of these cellular structures, says a PSU release.

Only two to three days after the injury, the one dendrite finally took on its new axonal microtubule polarity and began forming an axon. These findings were presented at the American Society for Cell Biology (ASCB) 49th Annual Meeting in the first week of December.

-- IANS