The Central Nervous System and Rheumatoid Arthritis

More proof that there is a mind/body connection. This is a study regarding the central nervous system and rheumatoid arthritis.

From ScienceDaily.com:

A study by researchers at the University of California, San Diego School of Medicine shows that, in rheumatoid arthritis, inflammation in the joints can be sensed and modulated by the central nervous system (CNS). The research suggests that the CNS can profoundly influence immune responses, and may even contribute to understanding so-called placebo effects and the role of stress in inflammatory diseases.

The central nervous system is not just a passive responder to the outside world, but is fully able to control many previously unanticipated physiologic responses, including immunity and inflammation," said Gary S. Firestein, M.D., Professor of Medicine, Chief of the Division of Rheumatology, Allergy and Immunology, and Director of UCSD's Clinical Investigation Institute, who led the study.

"This is an entirely new approach," Firestein said. "Instead of targeting enzymes at the actual site of disease, our hypothesis is that the central nervous system is a controlling influence for the body and can regulate peripheral inflammation and immune responses."

The scientists used a novel drug delivery system to administer miniscule amounts of a compound that blocks signals only in the CNS and then determined the influence of the treatment on peripheral arthritis.

We observed that the p38 signal is turned on, or activated, in the central nervous system during peripheral inflammation," Firestein said. "If we blocked this enzyme exclusively in a highly restricted site but not throughout in the body, inflammation in the joints was significantly suppressed."

Not only were clinical signs of arthritis diminished in those rats where p38 inhibitors were administered into the spinal fluid, but damage to the joint was also markedly decreased. The same dose of the inhibitors administered systemically had no effect.

The group also explored whether TNFĄ might also play a role in this observation. Using a TNF-inhibitor that is approved for use in rheumatoid arthritis and is usually given throughout the body, the scientists showed that delivering small amounts of this agent into the central nervous system also suppressed arthritis and joint destruction in the rats. They proposed that inflammation in the joints increases TNF production in the central nervous system, which, in turn, activates spinal p38. By blocking this pathway only in the spinal cord, they observed the same benefit that was normally achieved by treating the entire body with much higher doses.

The study also shows that the interactions between the CNS and the body are highly complex.