Serum relaxin levels in subjects with multiple sclerosis.

Multiple Sclerosis is an inflammatory, auto-immune, neurodegenerative disease of the central nervous system. The disease has a prevalence of approx 1:700 with at least 2.5 million cases worldwide. It is the leading, non-trauma cause of physical disability among young and mid- dle-aged adults. Recently developed therapies do reduce disease activity but only modestly, with all of the available agents producing significant side effects that reduce compliance, and/ or serious risk for adverse events. Relaxin has been long-recognized to play a critical role in pregnancy. Recent investigations have revealed that relaxin may be an important regulator of inflammation and immune processes. This is due to the ability of relaxin to promote the pro- duction of glucocorticoid receptors, increase serum levels of the adrenocorticotropic hormone and inhibiting cell-mediated pro-inflammatory activity by stimulation of the peroxisome prolif- erator-activated receptor gamma. This study found serum relaxin levels to be elevated in sub- jects with multiple sclerosis. Production of relaxin is down regulated by a negative feedback loop through its own receptor binding. Decreased receptor binding may contribute to the high- er level of relaxin seen in these patients and may lead to dysregulation of the inflammatory and immune pathways.