Dialogue between the brain and the immune system in inflammatory arthritis.

The crosstalk between the brain and the immune system in inflammatory arthritis is exerted mainly through the activation or downregulation of the hypothalamic-pituitary-adrenal (HPA), the hypothalamic-pituitary-gonadal (HPG), and the hypothalamic-autonomic nervous system (HANS) axes. In this review, we will present an overview of the most recent data regarding the regulation of these complex pathways of neuroendocrine response during the different phases of inflammatory arthritides such as rheumatoid arthritis (RA). Furthermore, the effect of the most recently available biologic therapies like anti-tumor necrosis factor (TNF-a) on the neuroendocrine function in patients with RA will be reviewed.