Scientists hope fish clues aid spinal cord injury treatment

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Edinburgh scientists hope the results of a study into the nervous systems of a species of small exotic fish could hold clues to new therapies for people with paralysing spinal cord injuries.

Edinburgh University researchers said they have uncovered a "vital mechanism" in the damaged spines of zebrafish that helps nerve connections to regrow.

Zebrafish can regain full movement within four weeks of injury.

For people, damage to the spinal cord is permanent and results in paralysis.

Scientists at Edinburgh University's Centre for Neuroregeneration said they have pinpointed "key molecules" that prompt damaged nerve fibres in zebrafish spinal cords to regenerate themselves.

The finding could pave the way for doctors to restore vital connections between the brain and muscles of the body lost after spinal cord injury in humans.

The researchers said they have found after injury to the spinal cord in zebrafish, wound-healing cells called "fibroblasts" move into the site of damage.

The fibroblasts produce a molecule called collagen 12, which changes the structure of the support matrix that surrounds nerve fibres.

This enables the damaged fibres to grow back across the wound site and restore the lost connections.

'Repair connections'

The scientists found fibroblasts are instructed to make collagen 12 by a chemical signal called "wnt".

Understanding these signals could hold clues for therapies to help heal the spinal cord after injury.

Dr Thomas Becker, of the Centre for Neuroregeneration, said: "In people and other mammals, the matrix in the injury site blocks nerves from growing back after an injury.

"We have now pinpointed the signals that remove this roadblock in zebrafish, so that nerve cells can repair connections that are lost after damage to the spinal cord."

The Edinburgh team will now try to establish whether triggering similar signals in other animals can help them to repair nerve connections damaged by spinal cord injuries.

The study, published in the journal Nature Communications, was funded by the Biotechnology and Biological Science Research Council. The German research funding organisation, DFG, also supported the research.