Inhibiting nighttime melatonin and boosting cortisol increase patrolling monocytes, phagocytosis, and myelination in a murine model of multiple sclerosis

Abstract

Multiple sclerosis: Understanding the role of melatonin Regulating melatonin levels holds promise as a therapy for multiple sclerosis (MS), but treatment must be tailored to each individual. In MS, the immune system destroys the myelin sheath surrounding nerves, disturbing brain–body communication. Melatonin, a sleep-inducing hormone, is known to play a role in MS, but results so far are inconsistent. Serge Rivest at Laval University in Québec City, Canada, and coworkers investigated how melatonin affects particular brain cell types in a mouse model. They found that maintaining melatonin levels at an intermediate level, where they regulate rather than enhance immune activity, could minimize myelin destruction in MS. They conclude that melatonin should not be considered a universal remedy for MS, but that melatonin levels should be monitored for each individual patient to account for lifestyle differences.