In MS there is a loss of myelin in the brain and spinal cord. Myelin can be repaired, but in progressive forms of MS, this is not complete leading to irreversible disability. Currently, there are no treatment options that are capable of repairing myelin damage for people with progressive MS and therefore there is a need to find ways to combat this.
A team at the Menzies Institute for Medical Research in Tasmania, led by Dr Kaylene Young and funded by MS Research Australia, has explored the use of a non-invasive method called repetitive transcranial magnetic stimulation (rTMS) to promote myelin production. This method uses a rapidly changing magnetic field to generate small electrical pulses in the brain, stimulating certain areas. This method is currently used to treat depression in people where anti-depressants have not been successful. There have also been a small number of rTMS clinical trials in people with MS, and in these trials, people have reported a reduction in fatigue, muscle spasticity and improved memory. However, how it leads to these benefits were unknown. But given that brain activity is known to promote myelin production and since rTMS stimulates brain activity it is hoped that this method may be used to repair myelin in progressive forms of MS.
Published in Glia, the study shows that multiple bursts of magnetic stimulation provided by rTMS to a laboratory model over a two week period increased the number of newborn myelin-producing cells in the cortex (outer layer of the brain). This increase was a result of the cells surviving longer than usual. However, these cells remained in an immature state and didn’t really contribute to myelin production.
The researchers next investigated whether increasing the length of rTMS from two weeks to four weeks would increase the number of mature myelin-producing cells in the brain, and indeed found this to be the case. The increase in mature myelin-producing cells helped contribute to the length of myelin, showing that rTMS can influence myelin production.
This exciting work has shown that rTMS can promote the production of myelin for the first time. Dr Kaylene Young, along with Professor Bruce Taylor at the Menzies Institute of Medical Research, was awarded the MS Research Australia-Macquarie Group Foundation Paired Fellowship. This Paired Fellowship links together the work of a researcher and clinician in the field of MS. One of the aims of this fellowship is to progress the work undertaken by Dr Young in this project and proceed to clinical trials to ultimately treat people with progressive forms of MS.