According to a study that was published in the journal Cell, melatonin acts on the immune system to influence the seasonal frequency of multiple sclerosis relapses.
In multiple sclerosis (MS), a person’s own immune system targets nerve cells, the brain, and spinal cord, resulting in the development of an autoimmune disorder. Previous studies have shown that vitamin D is important in preventing MS relapses. However, other researchers have found that the frequency of MS relapses increases during spring and summer, when vitamin D levels in the body are expected to be higher.
A recent study has found that melatonin is another environmental factor that affects the seasonal variability of MS relapses. Melatonin is a hormone that is influenced by the amount of daylight. The study showed that MS patients had a high level of melatonin in the fall and winter seasons, which was associated with a decreased frequency in MS relapses. The study further demonstrated that melatonin acts by balancing processes controlling the circadian rhythm and the immune system, which ultimately leads to the suppression of MS relapses. However, the authors caution that the use of melatonin to treat MS has yet to be tested. This study emphasizes the impact of environmental risk factors on autoimmune disorders.
Farez, MF, Mascanfroni ID, Mendez-Huergo SP, Yeste A, Murugaiyan G, Garo LP, Balbuena Aguirre ME, Patel B, Ysrraelit MC, Zhu C, Kuchroo VK, Rabinovich GA, Quintana FJ, Correale J. Melatonin contributes to the seasonality of multiple sclerosis relapses. Cell. 2015; 162: 1338-1352.
Written by Ana Victoria Pilar, PhD