Common creams used to treat athlete’s foot and eczema could undo the damage of multiple sclerosis, scientists claim.
The surprise discovery could pave the way to ground-breaking new therapies for the devastating auto-immune disease ,which affects around 2.5 million worldwide.
Scientists found that the anti-fungal agent miconazole and the steroid clobetasol both restored movement to mice paralysed by a rodent version of multiple sclerosis (MS).
In laboratory tests, they prompted inactive mouse and human stem cells to regenerate myelin, the protective insulation-like coating around nerve fibres that is destroyed by the disease.
Common creams used to treat athlete’s foot and eczema could cure multiple sclerosis, scientists claim
Dr Robert Miller, of the US team from Case Western Reserve University who carried out the study, said the results marked a significant breakthrough.
He said: ‘It was a striking reversal of disease severity in the mice.
‘The drugs that we identified are able to enhance the regenerative capacity of stem cells in the adult nervous system.
‘This truly represents a paradigm shift in how we think about restoring function to multiple sclerosis patients.’
Miconzanole is sold over the counter in most pharmacies as a cream to treat athlete’s foot, while clobetasol cream is commonly prescribed to treat eczema.
Although both drugs are widely used, a way must be found to use them safely as internal human treatments rather than creams or ointments before clinical trials can be considered.
The researchers are confident this problem can be solved, but have warned patients not to jump the gun by using the drugs prematurely.
Lead scientist Professor Paul Tesar, from Case Western Reserve School of Medicine, said: ‘We appreciate that some patients or their families feel they cannot wait for the development of specific approved medications, but off-label use of the current forms of these drugs is more likely to increase other health concerns than alleviate multiple sclerosis symptoms.
‘We are working tirelessly to ready a safe and effective drug for clinical use.’
WHAT IS MULTIPLE SCLEROSIS?
MS is a condition of the central nervous system, where the coating around nerve fibres (called myelin) is damaged, causing a range of symptoms.
The specific symptoms that appear depend upon which part of the central nervous system is affected and the job of the damaged nerve.
People with MS might suffer fatigue, vision problems and difficulties with walking, but the condition is different for everyone.
Symptoms can come and go and can vary greatly in terms of severity
There may be periods of relapse of varying length and severity.
At present, there is no cure for MS but the symptoms can be treated.
It is usually diagnosed in people aged 20 to 40, and it affects almost three times as many women as men.
Worldwide, it is estimated that more than 2.5 million people have MS.
MS occurs when the immune system attacks myelin, thereby disrupting the passage of nerve signals.
As the disease progresses, it produces symptoms ranging from mild numbness or tingling to full blown paralysis. Occasionally, it can prove fatal.
Although current treatments can slow progression of MS and reduce its symptoms, the disease remains incurable.
One new approach is to focus on special stem cells called oligodendrocyte progenitor cells (OPCs) that mature into myelin-producing cells.
While other scientists have looked at ways of replacing lost stem cells using transplantation techniques, the Case Western team set out to find a way of stimulating existing, but inactive, OPCs.
After screening 727 potential drug candidates, they identified two – miconazole and clobetasol – that coaxed the OPCs to form oligodendrocytes and repair nerve fibres stripped of myelin.
‘We know that there are stem cells throughout the adult nervous system that are capable of repairing the damage caused by multiple sclerosis, but until now, we had no way to direct them to act,’ said Prof Tesar.
‘Our approach was to find drugs that could catalyse the body’s own stem cells to replace the cells lost in multiple sclerosis.’
As well as testing the drugs on mice affected by MS, the scientists also observed their effect on human OPCs in the laboratory.
The response was similar to that seen in mouse cells, with miconazole exerting the most potent effect.
Co-author Dr Fadi Najm, also from Case Western Reserve University, said: ‘We have pioneered technologies that enable us to generate both mouse and human OPCs in our laboratory.
‘This uniquely positioned us to test if these drugs could also stimulate human OPCs to generate new myelinating cells.’
The drugs also hold out the promise of treatments for other diseases that involve myelin loss or dysfunction, including cerebral palsy, age-related dementia, optic neuritis and schizophrenia, the scientists believe.
British immunology expert Professor Daniel Altmann, from Imperial College London, said: ‘This study offers the highly attractive possibility of re-targeting existing, safe, drugs for the purpose of promoting therapeutic remyelination.
‘The data appear to suggest that the drugs can to some extent limit disability in experimental models of MS, though there is clearly much more to be optimised in this area, not least as the models tried thus far do not really look at effects on chronic demyelination.
‘However, particularly for patients with progressive MS – where it can be difficult to know how to impact the ongoing deterioration, these approaches offer the great advantage that these are tried, tested and safe drugs passed for use in humans.
‘Some caution is clearly warranted, however, when one considers the long haul from benefits in tissue culture models of myelination to a complex and diverse human disease such as MS.’
The findings were published in the journal Nature.