Neuroendocrine-immune system in patients with rheumatoid arthritis

Abstract The neuroendocrine-immune system plays an important role in maintaining homeostasis. Since patients with rheumatoid arthritis (RA) tend to be exposed to long-term physical and psychological stress during the course of the disease, it is hypothesized that their neuroendocrine-immune system will become dysregulated. In order to understand the disturbances in the neuroendocrine-immune systems objectively, we measured and compared various components of the peripheral blood which were considered to reflect the state of these systems, in patients with RA and in control individuals. The serum levels of norepinephrine, interleukin-6 (IL-6), and the CD4/CD8 ratio were higher, whereas the levels of β-endorphin, adrenocorticotropic hormone, and NK cell activity were lower in the RA subjects than in the control subjects. On the other hand, the serum levels of methionine-enkephalin, epinephrine, corticotropin-releasing factor, cortisol, and CD57 were not significantly different in the two groups. In addition, we demonstrated the effects of hearty laughter, deep emotion with tears, or general anesthesia on the neuroendocrine-immune system. What need the most attention are changes in the IL-6 levels of RA patients. Serum IL-6 levels in RA were significantly higher than in controls, and fell rapidly to as low as half of their initial value after a bout of hearty laughter. Our results suggest that adequate mental intervention might serve to modulate the neuroendocrine-immune system of RA patients which had failed for various reasons.