myelin

University at Buffalo researchers are working on ways to improve multiple sclerosis patients’ cognitive function and to repair damage to the mylein coating that protects nerve cells. The National Multiple Sclerosis Society awarded the researchers more than $1.1 million to conduct the studies. One, “The Effects of Working Memory…

Clene Nanomedicine says its pre-clinical studies demonstrate the remyelination effects of CNM-Au8, supporting its potential to treat multiple sclerosis (MS) and other demyelinating disorders. Clene presented its data in a session, “Nanocrystalline Gold As a Novel Remyelination Therapeutic for Multiple Sclerosis,” that took place at the third annual Americas…

The U.S. Food and Drug Administration has approved technology that the Swedish company SyntheticMR developed to give doctors more information from magnetic resonance imaging scans. This means the company can begin selling its SyMRI NEURO packages to American medical facilities. Traditional MRIs offer only one level of contrast when depicting tissue. SyMRI NEURO…

A novel imaging approach enables assessment of key nervous system deterioration in multiple sclerosis (MS), a new study in mice suggests. The research, “Development of a PET radioligand for potassium channels to image CNS demyelination,” was published in the journal Scientific Reports. MS is characterized by damage to myelin (a process called demyelination), which is an insulating sheath around axons (the long projections of neurons) that enables effective neuronal communication. As a result, patients experience a variety of symptoms, including muscle stiffness and weakness, fatigue and pain. Although existing MS medications suppress immune responses and reduce flare-ups, none can cure the disease. Despite the importance of demyelination in MS, scientists and clinicians do not currently have a way to directly image myelin damage. Magnetic resonance imaging (MRI) is used, but it does not enable the distinction between demyelination and inflammation, which are common in patients with MS. Upon myelin damage, voltage-gated potassium channels (cellular membrane proteins) become exposed. As a result, cells leak potassium, which impairs proper neuronal communication. This prompted researchers to develop a tracer that targets potassium channels. "In healthy myelinated neurons, potassium channels are usually buried underneath the myelin sheath," Brian Popko, PhD, the study’s senior author, said in a press release. Popko is a professor of neurological disorders and director of the Center for Peripheral Neuropathy at The University of Chicago. Exposed potassium channels can be targeted by the MS medication 4-aminopyridine (4-AP; dalfampridine), which partially repairs nerve conduction and mitigates MS symptoms. Using mouse models of MS, the researchers demonstrated that 4-AP binding to potassium channels is greater in demyelinated axons in comparison with well-myelinated axons. The greater binding of 4-AP led to its accumulation in damaged axons. Then, the team evaluated several fluorine-containing derivatives of 4-AP, and found that the most effective in binding to potassium channels was 3-fluoro-4-aminopyridine (3F4AP), which can be labeled with radioactive 18F. This labeling enables detection of demyelinated regions with a novel strategy based in positron emission tomography (PET). "3F4AP is the first tracer whose signal increases with demyelination, potentially solving some of the problems of its predecessors," said Pedro Brugarolas, PhD, first author of the study. Existing PET tracers bind to myelin. This translates to decreases in signal in the presence of myelin loss, “which can be problematic for imaging small lesions” Brugarolas noted. Importantly, the findings in mice were confirmed in monkeys. Experiments showed that the radiolabeled 3F4AP enters the primate brain and accumulates in areas with less myelin. Collectively, “these data indicate that [18F]3-F-4-AP may be a valuable PET tracer for detecting [central nervous system] demyelination noninvasively,” the team wrote. "We think that this PET approach can provide complementary information to MRI which can help us follow MS lesions over time," Popko said. The novel PET strategy enables the evaluation of therapies to repair myelination and also could help assess how much myelin loss is involved in other neurological disorders, such as traumatic brain injury and spinal cord injury, but also in diseases not commonly linked to demyelination, "such as brain ischemia, psychiatric disorders, and neurodegenerative diseases, including Alzheimer's," Popko concluded.

A combination therapy of low-dose methylprednisolone and interferon (IFN)-beta-secreting stem cells is effective in a mouse model of multiple sclerosis (MS), a new Korean study suggests. The research, “Effective combination of methylprednisolone and interferon β-secreting mesenchymal stem cells in a model of multiple sclerosis,” appeared in the…

The nerve-cell-protecting myelin sheath’s failure to remove cholesterol after the membrane has been damaged limits its ability to regenerate, German researchers report. Their finding has important implications for multiple sclerosis because a hallmark of the disease is nerve cell deterioration stemming from damaged myelin. Cholesterol is a waxy, fatty substance…

Protamine — an agent used to stop the anticoagulant effects of heparin — was seen to trigger remyelination in mice with myelin damage. But while pointing a way forward for studies of myelin regeneration in multiple sclerosis (MS), the research team underscored that protamine itself is not an optimal treatment candidate.

Editor’s note: Tamara Sellman continues her occasional series on the MS alphabet with this first of two columns about terms starting with the letter M. Symptoms of MS Memory problems Memory loss is a common complaint for people with MS. Even for those with no physical or…

A cell therapy intended to boost myelin regeneration — Q-Cells by Q Therapeutics — has received a green light from the U.S. Food and Drug Administration to proceed with a clinical trial in patients with transverse myelitis (TM), a disease that like multiple sclerosis is characterized by myelin damage. FDA approval of the company’s Investigational New…

Researchers managed to change the immune system — replacing inflammation with immune tolerance — in a mouse model of multiple sclerosis (MS) using so-called quantum dots, or nano-sized particles carrying pieces of myelin. Experiments with this advanced technological solution may help researchers design MS therapies that are based on promoting regulatory T-cells rather…

A physical scaffold that allows lab-grown brain cells to grow in a three-dimensional manner is giving scientists a whole new way of studying the regeneration of myelin, nerve coatings whose damage is at the heart of multiple sclerosis. The scaffold is allowing researchers to test large numbers of compounds for…

Scientists at the University of Maryland have developed an experimental treatment to control the immune system and recover movement in a paralyzed mouse model of multiple sclerosis (MS). The team presented its research April 2 during the 253rd National Meeting & Exposition of the American Chemical Society in San Francisco. In…

Using a small RNA molecule belonging to the family of microRNAs (miRs), scientists could restore myelin in nerve cells and improve limb function in mouse models of human multiple sclerosis (MS). The study, “miR-219 Cooperates with miR-338 in Myelination and Promotes Myelin Repair in the CNS,” was published in…