Green Tea Compound May Reduce Effects of Rheumatoid Arthritis

Researchers treated mice with transforming growth factor β–activated kinase 1 (TAK 1) in order to examine the post-translational modification to TAK 1 and its therapeutic regulation in rheumatoid arthritis. The team used a phytochemical known as epigallocatechin 3 gallate (a compound commonly found in green tea) in a 10-day treatment plan in the mice to study the effects.

Components found in green tea can block rheumatoid arthritis (RA), according to findings published in Arthritis & Rheumatology.

Researchers from Washington State University used mice models that were administered transforming growth factor β—activated kinase 1 (TAK 1) in order to examine the post-translational modification to TAK 1 and its therapeutic regulation in RA. In this novel approach, the team used a phytochemical known as epigallocatechin 3 gallate (EGCG) in a 10-day treatment plan in the mice to study the effects. EGCG is a compound commonly found in green tea, the researchers added. The rats with modeled RA were given 50 mg/ kg/ day for 10 days.

“Existing drugs for rheumatoid arthritis are expensive, immunosuppressive and sometimes unsuitable for long-term use,” Salah-uddin Ahmed, the lead WSU researcher on the project, explained in a press release.

ECGC was found to effectively block the effects of RA without disrupting other cellular functions, the researchers said.

“This study has opened the field of research into using EGCG for targeting TAK1 - an important signaling protein — through which proinflammatory cytokines transmit their signals to cause inflammation and tissue destruction in rheumatoid arthritis,” added Ahmed, who has been investigating RA for the past 15 years.

The researchers observed significantly reduced ankle swelling in the mice during the 10 day treatment, but noted that the experiment was done in a preclinical trial setting.

The investigative team also found that ECGC enhanced the proteasome associated deubiquitinase expression which prohibited some of the proteins from proteasomal degradation.

“Our findings provide a rationale for targeting TAK1 for the treatment of RA with EGCG,” the study authors concluded.