Molecular Pathogenesis via Sex Hormone in Sjögren's Syndrome

A lot of autoimmune diseases are known to develop in postmenopausal women. However, the mechanisms by which estrogen deficiency influences the onset or development of autoimmunity remain unclear. Sjögren's syndrome (SS) is characterized by a 9 : 1 ratio of women/men. In particular, almost patients with SS are postmenopausal women. Drastic change of estrogenic action in women has been discussed for a long time in the points of the phenotypes, functions and signaling pathways of immune cells and target cells in autoimmunity. Estrogen deficiency due to menopause influences the systemic homeostasis including immune system. Phonotypic changes of immune cells or dysfunction of target cells are associated with the onset or development of autoimmune diseases, such as SS. In this review article, the roles of estrogen were focused on to understand the pathogenesis of SS based on the previous data including our reports.