Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease of the central nervous system (CNS) in which demyelination and neurodegeneration occurs. The immune system of MS patients is characterized by a dysregulation in the balance between pro- and anti-inflammatory immune cells, whereby both the innate and adaptive immune system are involved
An autoimmune disease develops when the immune system fails to
recognize self from non-self and mounts an immunologic response
damaging its own tissues.
With the advent of biological therapies, better outcomes have recently been noted in the management of autoimmune diseases. Nonetheless, recent research highlights the salient role of modifiable behaviors such as physical inactivity on various aspects of the immune system and autoimmune diseases. Physical activity leads to a significant elevation in T-regulatory cells, decreased immunoglobulin secretion and produces a shift in the Th1/Th2 balance to a decreased Th1 cell production.
The immune system has developed many effective ways to protect an individual from environmental insults and disease. Adaptive (specific) immunity will focus these defensive efforts very specifically on a given antigen in order to remove and/or destroy it.
However, when this specific response is directed against self-antigen, the result is autoimmune disease. Autoimmune disease is defined as a disease caused by a breakdown of self-tolerance such that the adaptive immune system responds to a self (autologous)-antigen and causes cell and tissue damage.
In the context of autoimmunity, many studies support the existence of an immunomodulating role of vitamin D, which has been shown to have an inhibitory effect on type 1 T helper cells (Th1), cells that have
been previously associated with autoim-mune processes, and specifically in organ-specific autoimmune diseases.