Tag: multiple sclerosis

MS Likely Caused by Epstein-Barr Virus

Source: NCI on Unsplash

Multiple sclerosis (MS) is likely caused by infection with the Epstein-Barr virus (EBV), according to a new Harvard University study.

“The hypothesis that EBV causes MS has been investigated by our group and others for several years, but this is the first study providing compelling evidence of causality,” said senior author Professor Alberto Ascherio. “This is a big step because it suggests that most MS cases could be prevented by stopping EBV infection, and that targeting EBV could lead to the discovery of a cure for MS.” The findings were published in Science.

Currently incurable, MS is a chronic inflammatory disease of the central nervous system that attacks the myelin sheaths protecting neurons in the brain and spinal cord. One of the top suspects for its cause is EBV, a herpes virus that can cause infectious mononucleosis and establishes a latent, lifelong infection of the host. Establishing a causal relationship between the virus and the disease has been hard because EBV infects approximately 95% of adults, MS is relatively rare, and the onset of MS symptoms begins about ten years after EBV infection. To determine the connection between EBV and MS, the researchers conducted a study among over 10 million US military personnel, identifying 955 who were diagnosed with MS during their period of service.

The team analysed serum samples taken twice a year by the military and determined the soldiers’ EBV status at time of first sample and the relationship between EBV infection and MS onset during the period of active duty. In this cohort, the risk of MS increased 32-fold after infection with EBV but remained unchanged after infection with other viruses. Serum levels of neurofilament light chain, a biomarker of the nerve degeneration typical in MS, increased only after EBV infection. The findings cannot be explained by any known risk factor for MS and suggest EBV as the leading cause of MS.

The delay between EBV infection and the onset of MS may be partly a result of the disease’s symptoms being undetected early on and partly the evolving relationship between EBV and the host’s immune system, which is repeatedly stimulated whenever latent virus reactivates.

“Currently there is no way to effectively prevent or treat EBV infection, but an EBV vaccine or targeting the virus with EBV-specific antiviral drugs could ultimately prevent or cure MS,” Prof Ascherio said.

Source: Harvard University

Hydroxychloroquine Effective in Slowing MS

A healthy neuron.
A healthy neuron. Credit: NIH

Promising results for a generic antimalarial drug, hydroxychloroquine, have been seen when used to treat the evolution of disability of primary progressive multiple sclerosis (MS), the least treatable form of the autoimmune disease.

Research teams led by Dr Marcus Koch, MD, PhD, and Dr Wee Yong, PhD, found that hydroxychloroquine helped to slow the progression of disability during the 18-month study involving participants at the MS clinic in Calgary. The research was published in Annals of Neurology.

“With primary progressive MS, there is no good treatment to stop or reverse the progression of disease. The disability progressively worsens through time,” said Dr Koch. “Dr Yong’s research team, with whom we closely collaborate, has been screening a large number of generic drugs over several years and the results with hydroxychloroquine show some promise. Our trial is a preliminary success that needs further research. We hope sharing these results will help inspire that work, specifically larger scale clinical trials into the future.”

The experimental study followed 35 people, at least 40% of whom, or 14 participants, were expected to experience a significant worsening of their walking function, but at the end of the trial only eight participants had worsened.

Hydroxychloroquine is an anti-malaria medication more commonly used to manage the symptoms of rheumatoid arthritis and autoimmune conditions such as lupus. It was selected as it is use in rheumatological diseases is widespread and is generally well-tolerated.

“Based on research in our lab on models of MS, we predicted that hydroxychloroquine would reduce disability in people living with MS. Calgary has a vibrant bench-to-bedside MS program and the work from Dr Koch’s trial offers further evidence which we were pleased to see,” said Prof Yong.

To date, the cause of MS is unknown. This autoimmune disease generally long-lasting, often affecting the brain, spinal cord and the optic nerves in your eyes. It can cause problems with vision, balance and muscle control, although the effects are different for every patient with the disease.

Dr Koch and the research team have been studying the impact of hydroxychloroquine on primary progressive MS for several years and that work continues, including its potential to achieve even greater results as a therapy in combination with select other generic drugs.

Source: EurekAlert!

Green Light for New Device for MS Treatment

The American Food & Drug Administration has approved a new device for treating gait deficits in multiple sclerosis (MS) patients.

The Portable Neuromodulation Stimulator (PoNS), generates electrical pulses on the tongue to stimulate trigeminal and facial nerves to treat motor deficits. The FDA said that for it to be available by prescription, must be part of a supervised therapeutic exercise program in MS patients 22 and older. The device was authorised through the FDA’s ‘de novo’ premarket review pathway for new devices which pose do not pose significant risks of adverse effects.

In a statement, Christopher Loftus, MD, acting director of the Office of Neurological and Physical Medicine Devices in the FDA’s Center for Devices and Radiological Health, said: “MS is one of the most common neurological diseases in young adults. Today’s authorisation offers a valuable new aid in physical therapy and increases the value of additional therapies for those who live with MS on a daily basis.”

Onset of MS symptoms, which can include difficulties with walking and balance, typically occurs between 20 and 40, with greater frequency in women.

The PoNS device electrical stimulates the dorsal surface of the patient’s tongue. A control unit is worn around the neck which sends signals to a mouthpiece which the patient keeps in place with lips and teeth. Later, usage data can be viewed by a therapist to spot “potential areas of missed or shortened sessions,” the FDA noted.

The FDA gave their approval based on two clinical studies. One involved 20 MS patients with gait deficits (half with PoNS; half with a sham device). Th FDA said that the PoNS group showed “statistically significant and clinically significant” improvement in Dynamic Gait Index (DGI) scores at 14 weeks not seen in the sham device group.

The other study, with 14 patients, showed improvements from baseline in sensory organisation task scores (but not in DGI scores) at 14 weeks. There were no serious safety or adverse effects reported.

Among the FDA’s cautions, the FDA stated that the PoNS device should not be used by patients with penetrating brain injuries, neurodegenerative diseases, oral health problems, chronic infectious diseases, unmanaged hypertension or diabetes, pacemakers, or a history of seizures.

Source: MedPage Today

With Climate Change, Heat May Worsen Multiple Sclerosis Symptoms

As average global temperatures increase due to climate change, multiple sclerosis (MS) patients can experience worsening symptoms resulting in an increase in hospital visits.

Some 60% to 80% of MS patients experience heat sensitivity. Increased body temperature slows or stops nerve signals in damaged nerves, which has a number of impacts such as blurred vision and other neurological effects. Heat sensitivity is also correlated with fatigue. Together with fatigue, divided attention from heat sensitivity can contribute to falls.

“We know that heat sensitivity is common in multiple sclerosis, and climate scientists expect that periods of anomalously warm weather will become more frequent with climate change,” said study author Holly Elser, PhD. of Stanford University School of Medicine. “Our study suggests that warming trends could have serious health implications over the long term for people living with MS.”

The study defined anomalously warm weather as a month in which local average temperatures were higher than the long-term average temperature for that month by at least 1.5C.

The researchers drew data on insurance claims for 106 225 people with MS living in the US, and then calculated the estimated effect of anomalously warm weather on MS-related emergency department, inpatient and outpatient visits. Then, the number of medical visits for each person during anomalously warm weather periods was compared to those for periods of normal weather periods.

During anomalously warm weather periods, there was a 4% increased chance of an emergency department visit compared to periods of normal weather. Participants had a 3% increased chance of having an inpatient visit and a 1% increased chance of having an outpatient visit during anomalously warm periods compared to periods of normal weather.

Researchers estimate that during the follow-up period, anomalously warm weather periods were linked to an estimated excess of at least 592 emergency department visits, 1260 inpatient visits and 1960 outpatient visits related to MS.

“While the relative increase in risk of visits is small, the associated absolute effect on people with MS and the health care system is meaningful,” concluded Dr Elser.

Source: Medical Xpress

Promising Drug May Worsen Instead of Treat Multiple Sclerosis

A drug, TEPP-46,  that is being assessed to treat multiple sclerosis (MS) may in fact be worsening the progression of the disease, wrote University of Virginia on the Medical Xpress website.

MS is a debilitating disease which affects over one million people in America, in which the immune system attacks the myelin sheath, creating a range of effects in sufferers, from muscle spasms to numbness.

Presently available drugs to treat MS often have unwanted side effects, such as weakening the immune system. Originally developed to fight cancer, TEPP-46 is small-molecule drug that targets the changes in cellular metabolism that occur in both cancer and MS. However, the drug has been shown to produce off-target effects. In the mouse model used by the researchers, the inflammation was directed away from the spinal cord and into the brain. The researchers believed that this was the result of the drug harmfully changing T cells, but could not explain why. 

“It was not at all what we expected,” said MS researcher Alban Gaultier, PhD, of University of Virginia. “The take-home message is that we should be very careful and do more fundamental research before we propose to take this to clinical trials.”