Around 40 million Americans suffer from rheumatoid arthritis, and currently treatment is aimed at pain control rather than cure.
Using a mouse model of rheumatoid arthritis, Mario Delgado and colleagues discovered that injections of VIP delayed onset of the disease by reducing the severity of arthritis. It also prevented joint swelling and destruction of cartilage and bone.
VIP-treated mice suffered no remission 2 weeks after stopping injections, and VIP improved disease that was already established.
|VIP may decrease inflammatory cytokine production|
The scientists believe that VIP works by decreasing the production of inflammatory cytokines and by modulating the action of inflammatory lymphocytes known as Th1.
Gary Firestein from University of California, San Diego, discusses the findings in a News and Views article. He points to potential pitfalls of using the peptide for therapy, such as gastrointestinal side-effects, but ultimately concludes that the risk to benefit ratio is a favorable one, since the condition affects so many people.