In rheumatoid arthritis, a person's own immune system attacks the joints by activating the synovial tissue that lines the body's movable joints, causing inflammation, swelling, pain and eventually erosion of the bone and cartilage and deformation of the joint. It is among the most debilitating forms of arthritis, often making difficult even the simplest of daily activities.
In a study presented April 29 at Experimental Biology 2007, University of Michigan Medical School scientist Dr. Salah-uddin Ahmed reports that a compound derived from green tea was able to inhibit production of several immune system molecules involved in inflammation and joint damage. The compound, named epigallocatechin-3-gallate (EGCG), an active principal of green tea extract, is a potent anti-inflammatory molecule, and also was able to inhibit production of interleukin-6 (IL-6) and prostaglandin E2, the inflammatory products found in the connective tissue of people with rheumatoid arthritis.
Dr. Ahmed's Experimental Biology presentation was part of the scientific program of the American Society for Nutrition.
Synovial fibroblasts (cells that form a lining of synovial tissue surrounding the capsule of the joints) were isolated from the joints of the patients suffering from rheumatoid arthritis, cultured in growth medium, and incubated with EGCG. Synovial fibroblasts were then stimulated with pro-inflammatory cytokine IL-1, a protein of the immune system known to play an important role in causing joint destruction in rheumatoid arthritis.
In an earlier study published by Dr. Ahmed's research group last fall, the researchers showed some interesting and novel findings when EGCG pretreated synovial fibroblasts were stimulated with the cytokine IL-1 to study the protective effect of this green tea compound. Compared to untreated synovial fibroblasts, the cells treated with EGCG markedly blocked IL-1's ability to produce the proteins and enzymes that in
Contact: Sylvia Wrobel
Federation of American Societies for Experimental Biology