Heart medication helps with remyelination in mouse study

Digoxin, a prescription-only drug for heart problems, has been found to promote myelin repair in a mouse model of multiple sclerosis (MS).

Most drugs for MS modulate the immune system to try and control inflammation, but there is yet to be one available for repairing myelin damage.

When combined with an experimental immune-modulating therapy, the combination promoted myelin repair more effectively that either treatment used alone.

Digoxin is used for heart failure and an irregular heartbeat. In laboratory dishes, treatment of immature oligodendrocyte progenitor cells (OPCs) with the drug caused them to mature into myelin-making oligodendrocytes.

Researchers then injected mice with chemically-induced myelin loss with digoxin, which increased remyelination, accompanied by an increase in mature oligodendrocyte cells. They noticed the remyelination was present before the change in oligodendrocyte cell numbers. This suggests the drug works by “restabilising oligodendrocyte function in existing mature cells and/or promoting the natural turnover of dysfunctional oligodendrocytes and maturation of the OPC population,” the team added.

The researchers then tested a combination of digoxin and PLG-MOG, and experimental therapy designed to encourage immune tolerance of myelin. A single dose of LG-MOG reduced symptom severity in mice, both when given alone and with digoxin, and more than just digoxin alone did.

The researchers are now planning a phase 1 trial of digoxin in people with MS along with currently approved disease-modifying therapies.