Tiny 'sticking plaster' nanoparticles for broken nerves could provide spinal cord treatment

Scientists last night raised hopes that microscopic nanoparticles could be injected into the spines of paralysed people to help them walk again.



They have conducted experiments on rats which show that the tiny particles can act as a 'sticking plaster' to repair broken nerves.



When the microscopic spheres, known as micelles, were injected into the tails of paralysed rats, they regained the use of all their limbs.

A new 'sticking plaster' technique could repair damaged spinal cords, helping people to walk again

However, the scientists warned it would take many years of research before it was known whether the same technique could work on humans.



Work has been going on for years to see whether micelles, which are about 100 times smaller than red blood cells, could help deliver drugs to different parts of the body.



But this is the first time it has been shown that the micelles can themselves assist the repair of nerve fibres.



In rats, they boosted the repair of damaged nerve cells by 60 per cent.



Dr Ji-Xin Cheng, from Purdue University in West Lafayette, Indianopolis, said: 'That was a very surprising discovery. Micelles have been used for 30 years as drug-delivery vehicles in research, but no-one has ever used them directly as a medicine.'



The micelles used in the experiment had an outer shell made from polyethylene glycol (PEG), a sealing agent that has been investigated as a potential spinal injury treatment.



Previous research has shown the chemical can seal the injury site, prevent further damage setting in, and give the nerves a chance to repair themselves.



Secondary damage caused by the flood of biochemical signals and cell death that follows spinal injury is one of the main causes of permanent disability.



Dr Cheng's research showed that PEG-coated micelles were more effective than PEG injected on its own. In tests, the nanoparticles were successfully delivered to areas of damage, and the rats treated with micelles recovered co-ordinated control of all four limbs, whereas those treated with conventional PEG did not.



The nanoparticles were also shown to be non-toxic at the concentrations required. 'With the micelles, you need only about one hundred thousandth the concentration of regular polyethylene glycol,' said Dr Cheng.



The findings were published yesterday in the journal Nature Nanotechnology.

