Breakdown of myelin protein may cause MS

Researchers from the University of Wollongong (UOW) have been studying the key structural proteins of myelin and, in doing so, may have discovered the cause of multiple sclerosis (MS).

MS is an autoimmune disease where the body attacks its own nerves, with symptoms including muscular spasms, visual disturbances and problems with weakness, coordination, balance and functioning of the arms and legs. There is no cure and the drugs available typically target the inflammatory response, rather than the cause of the disease.

Now, new hope has presented itself in the form of research into myelin — a substance that coats axons — by Professor Roger Truscott and Dr Michael Friedrich at UOW’s Illawarra Health and Medical Research Institute (IHMRI). Myelin acts as an electrical insulator for axons — known as the wiring cables of nerve cells — and acts as allowing greater speed in the conduction of nerve impulses.

“It was the aim of this study to examine the abundant myelin protein, myelin basic protein (MBP), to determine if there are sites of modification that may be characteristic for MS,” the researchers wrote in the journal Acta Neuropathologica Communications. “MBP from the cerebellum was examined from controls and MS patients across the age range using mass spectrometry and amino acid analysis.”

The scientists found that MBP naturally breaks down as part of the ageing process but does not tend to affect the ability of myelin to function as an insulator of electrical signalling in the brain. But in people with MS, the protein breaks down differently, causing the researchers to theorise that this may be the characteristic that triggers an autoimmune response.

“The structure of the MBP from MS patients had two regions where specific changes have accumulated,” said Professor Truscott. “We hypothesise, based on the novel structures formed here, that these two regions provoke an immune response.”

Professor Truscott said the discovery could represent a breakthrough in identifying the cause of MS and thus progress work towards preventing the disease. He suggested, “In the future, drugs could be designed to bind specifically to these two regions on MP and thus potentially stop the autoimmune response.

“It is important to emphasise that this is not a cure for MS; however, for the first time, we have a target.”

Pictured: Professor Roger Truscott and Dr Michael Friedrich. Image credit: UOW photographer Paul Jones.