Compound in green tea found to block rheumatoid arthritis

Washington State University is deploying its land-grant mission to achieve broad societal impact in today’s world. With this commitment to public service top of mind, WSU is focusing its research, innovation and creativity in the specific areas of sustaining health, sustainable resources, opportunity and equity, smart systems, and national security in order to target critical national and global problems.

WSU pharmacy faculty contribute to these initiatives through research that protects, promotes and improves human health. Recently making steps toward developing new treatments that address the onset and progression of disease, Pharmaceutical Sciences Associate Professor Salah-uddin Ahmed and his research team at the WSU College of Pharmacy in Spokane have identified a potential new approach to combat the joint pain, inflammation, and tissue damage caused by rheumatoid arthritis.

Their discovery is featured on the cover of Arthritis and Rheumatology, a journal of the American College of Rheumatology, in print Tuesday, February 16.

Rheumatoid arthritis is a debilitating autoimmune disorder that affects the quality of life for an estimated 1.5 million Americans. It mostly affects the small joints of the hands and feet. It causes painful swelling that progresses to cause cartilage damage, bone erosion, and joint deformity.

“Existing drugs for rheumatoid arthritis are expensive, immunosuppressive, and sometimes unsuitable for long-term use,” said Ahmed.

His team evaluated a phytochemical called epigallocatechin-3-gallate (EGCG), which is a molecule found in green tea with anti-inflammatory properties. Their experimental study suggests that EGCG has high potential as a treatment for rheumatoid arthritis because of how effectively the molecule blocks the effects of the disease in synovial fibroblasts, a cell type that is actively involved in causing joint destruction in rheumatoid arthritis.

They also confirmed this finding in pre-clinical animal model of human rheumatoid arthritis, where ankle swelling in the animals given EGCG in a 10-day treatment plan was markedly reduced.

“Our findings provide a scientific rationale for targeting TGFß-activated kinase 1 (TAK1) in the treatment of rheumatoid arthritis using EGCG as a ‘small-molecule’ inhibitor or developing more selective and potent inhibitors of TAK1. TAK1 is an important signaling protein through which pro-inflammatory cytokines transmit their signals to cause inflammation and tissue destruction in rheumatoid arthritis,” said Ahmed.

Ahmed has focused his research on studies related to rheumatoid arthritis for the last 15 years.

The WSU team, which includes researchers Anil Singh and Sadiq Umar, have been studying rheumatoid arthritis and other inflammatory diseases at the WSU College of Pharmacy in Spokane, Washington, since 2014. They teamed up with researchers from the National Institute of Pharmaceutical Education and Research in Hajipur, India, for this project.

Their work was funded in part by the National Institute for Arthritis and Musculoskeletal and Skin Diseases (NIAMS), which is part of the National Institutes of Health (AR-063104), the Arthritis Foundation, and Washington State University.

“Our obvious next step will be to understand the bioavailability of EGCG using different routes of administration, and study the potential EGCG-conventional drug interactions for safety evaluation in pre-clinical studies,” said Ahmed. “Success of these pre-clinical safety pharmacology studies will provide rationale to move forward for the clinical testing of EGCG.”

[March 1, 2016] By: Lori J. Maricle