Gender hormones: role in the pathogenesis of central nervous system disease and demyelination

Gender hormones are associated with the evolution of Multiple Sclerosis (MS) like changes in experimental models of MS. Several clinical studies have attempted to elucidate the role of gender hormones in the evolution of the clinical spectrum of the disease. We attempt to describe the currently known data regarding such associations emphasizing the potential clinical applications in different MS scenarios i.e. pregnancy, menstruation, use of oral contraceptives and hormonal replacement therapy. Moreover we discuss relevant effects of gender hormones on immunological parameters relating to MS pathogenesis. Beneficial neuroprotective effects were noted for elevated levels of estrogens, progesterone and elevated dosages of androgens. Some of these changes may be explained by a favorable immunological shift from a Th1 to Th2 response. Further elucidation of the clinical implications of such associations is necessary.