Scientists have found a new cellular mechanism which may cause the disease, and a potential hallmark which could be a target for future treatment of the autoimmune disorder.
Multiple sclerosis affects around 2.5 million people around the world. Typically, people are diagnosed in their 20s and 30s, and it is more common in women than men.
Scotland has one of the highest concentrations of MS, with one in 500 people suffering from the disease.
Although the cause has so far been a mystery, the disease causes the body’s own immune system to attack myelin – the fatty sheaths which protect nerves in the brain and spinal cord.
This leads to brain damage, a reduction in blood supply and oxygen and the formation of lesions in the body.
Symptoms can be wide-ranging, and can include muscle spasms, mobility problems, pain, fatigue, and problems with speech.
Scientists have long suspected that mitochondria, the energy-creating “powerhouse” of the cell, plays a link in causing MS.
Using human brain tissue samples, researchers at the Universities of Exeter and Alberta found a protein called Rab32 is present in large quantities in the brains of people with MS – but is virtually absent in healthy brain cells.
Where Rab32 is present, the team discovered that a part of the cell which stores calcium gets too close to the mitochondria.
The resulting miscommunication with the calcium supply triggers the mitochondria to misbehave, ultimately causing toxicity for brain cells in people with MS.
Researchers do not yet know what causes the influx of Rab32 but they believe the defect could originate at the base of the cell.
The finding will enable scientists to search for effective treatments that target Rab32 and embark on determining whether there are other proteins which could pay a role in triggering MS.
Professor Paul Eggleton, of the University of Exeter Medical School, said: “Multiple sclerosis can have a devastating impact on people’s lives, affecting mobility, speech, mental ability and more.
“So far, all medicine can offer is treatment and therapy for the symptoms – as we do not yet know the precise causes, research has been limited.
“Our exciting new findings have uncovered a new avenue for researchers to explore. It is a critical step, and in time, we hope it might lead to effective new treatments for MS.”
The research has been published as part of MS Awareness Week.
The paper is published in the journal Neuroinflammation.
CASE STUDY: CLAIRE THACKRAY
When Claire Thackray
suddenly went blind in one eye at the age of 25, she initially put it down to crying too much after a break-up.
Her vision was affected for a month, and medical investigations initially drew a blank – but within months, MS was identified as the cause.
“I was completely floored,” said Ms Thackray, now 32, and from Taunton in Somerset.
“There’s no history of MS in my family – it hadn’t occurred to me at all. Initially I thought my life was over, and that I was on a downward spiral to disability and a wheelchair.
“Thankfully that hasn’t been the case at all.
“I really welcome this new research – it’s really important to move forward in our understanding about what goes on in the brain in people with MS.”
CASE STUDY: TRISH DEYKIN
Trish Deykin, loved her job as a crime scene investigator, but began to experience unexplained symptoms that increasingly interfered with her work.
She was 28 when she first encountereddeveloped pins and needles which made touching water agony – a serious hindrance for the keen swimmer.
“At first, doctors told me it was all in my head. I knew it was physical, but at times I did feel that I was losing my mind,” she said.
Soon the strange sensation was accompanied by agonising pain in her eyes.
“It felt like someone was constantly stabbing me in the eye,” said Ms Deykin, from near Yelverton in West Devon.
“I had a lazy eye and I initially though it was part of that. I wasn’t too worried.”
However, friends encouraged her to see specialists, and within a year, she had been diagnosed with multiple sclerosis.
By then, her symptoms were escalating, and included problems with memory and concentration, a leg that would involuntarily collapse without warning, poor dexterity and a burning sensation in her legs.
Ms Deykin had no choice but to take early retirement eight years after her diagnosis at 36 and she moved back to Devon from Sussex to be near her family.
“I was absolutely gutted to retire - it was my dream job I’d worked so hard to get there,” she said.
“But doctors told me that if I carried on working so hard, I’d be in wheelchair within six months. If I retired and took it easier, I could retain a better quality of life.
“It was a no-brainer but it was a big smack in the face for me.”
Taking life at a slower pace has made a big difference.
“I feel my symptoms have levelled out now and I hope it stays that way,” With MS, you never know what’s around the corner,” she said.
“I’m staying active with horse riding and swimming and enjoying life. I feel positive and I really welcome this new research.
“Finding a cause will help everyone who has MS - even if that’s just knowing more about what’s going on in their own brains.”