THURSDAY, June 2, 2005 (HealthDay News) -- A protein called tumor necrosis factor (TNF) is linked with a deficiency of male sex hormones in people with rheumatoid arthritis, according to a European study.
The finding may give researchers new insights into the underlying causes of this common, debilitating disorder.
TNF is involved in multiple cell functions and is also known to provoke destructive inflammation. It's believed that male sex hormones -- androgens -- play an important role in helping fight inflammation in rheumatic diseases, including various forms of arthritis and lupus. In this study, researchers took a closer look at TNF's impact on androgen production.
Specifically, researchers at University Hospital Regensburg, in Germany, focused on TNF's role in the conversion of a biologically inactive compound, dehydroepiandrosterone sulfate (DHEAS), to the more biologically active DHEA -- the steroid hormone "parent" of androgen, estrogen and testosterone.
They analyzed samples of inflamed synovial tissue from the knee joints of 37 people with either rheumatoid arthritis or osteoarthritis. Levels of both DHEAS and DHEA were much lower among the rheumatoid arthritis patients than patients with (non-rheumatic) osteoarthritis, the team reported in the June issue of Arthritis & Rheumatism.
The researchers also found evidence that TNF inhibits the activity of steroid sulfatase, an enzyme that plays a crucial role in DHEAS-to-DHEA conversion.
"This is the first study to demonstrate that the conversion of DHEAS to DHEA is decreased in patients with rheumatoid arthritis as compared with that in patients with osteoarthritis," noted leading contributor Claudia Weidler.
She and her colleague said their study provides more information about androgen deficiency in people with rheumatoid arthritis and confirms the need for more research into the use of TNF-blocking drugs as a potential early treatment for the disease.
More information
The Arthritis Foundation has more about rheumatoid arthritis.
