Paralysed dogs made to heal

A pioneering treatment has allowed paralysed dogs to regain some movement and has been successful in being able to walk again.

So far, nine dogs paralysed in road accidents or by spinal disc injuries have been treated by veterinary surgeons Robin Franklin and Nick Jeffery of the University of Cambridge. Within a month, all regained the ability to make jerky movements in their hind legs, Jeffery told a meeting in Birmingham and that they are slowly gaining the ability to support their own weight.

Researchers said, "Dogs rendered paraplegic by severe spinal cord injuries regained significant neurological functions after treatment with a polymer called polyethylene glycol or PEG".

PEG is widely used in the cosmetics industry and in some formulations, as a laxative. It is believed that the polymer repairs damaged cells by patching holes in damaged membranes and 'stitching' several cells backs together.

Richard Borgens of Purdue’s Centre for Paralysis Research told New Scientist Magazine, "When the membrane is comprised, the hydrophobic (fatty) core is exposed, and water gets in through that breach.

"Because PEG is strongly hydrophilic (water loving), it sucks up water and plugs into the breach, and then the fatty acids and lipids in the centre of the membrane resolve into each other."

Borgens’s use of PEG is an unusual approach in the world of spinal cord repair where most research programmes are focused on coaxing nerve fibres to regenerate using stem cells or growth factors. The new study design is also unusual in that it relied on naturally occurring injuries and used historical controls rather than following standard placebo-controlled procedures.

Geoffrey Raisman of the institute of Neurology at University College London said "I think that these findings in dogs are directly relevant to the human situation. Of course, we can’t know for sure without doing the work but it is a very good indicator that we can expect the same effects. We are hoping to start similar trials in humans within a couple of years."

Jeffery agrees that the results seen in the nine dogs are encouraging, but says a full recovery may require a combination of methods. "It is exceedingly improbable that one simple intervention alone will permit full recovery of locomotors activity after this type of extremely severe spinal cord injury," he cautions.