Researchers at Aarhus University report that the hormone GLP-1—mimicked by drugs such as Wegovy—can be measured in the joint fluid of patients with inflammatory arthritis, but only at very low levels. The findings, published in The Lancet Rheumatology, suggest GLP-1–based medicines might eventually be studied for potential direct effects on joint inflammation, though the researchers say clinical trials are needed to show whether such treatment works.
Researchers at Aarhus University analyzed paired blood and synovial (joint) fluid samples from patients with inflammatory arthritis, including rheumatoid arthritis and spondyloarthritis.
According to the researchers, measurements showed that the body’s own GLP-1 was present in synovial fluid only in very small amounts. They also found that GLP-1 levels in joint fluid were closely linked to the concentrations circulating in the bloodstream—suggesting that how much GLP-1 reaches the joint largely depends on how much is present in the blood.
The team said the work represents the first direct detection of GLP-1 in the synovial fluid of arthritis patients, and argued it provides a biological rationale to investigate whether GLP-1–based medications—delivered at far higher doses than the hormone’s natural levels in joints—could potentially influence inflammation inside the joint.
However, the researchers cautioned that the study does not demonstrate that GLP-1 drugs treat arthritis, and they said further clinical studies are required to determine whether such medications reach joints in sufficient quantities and meaningfully reduce joint inflammation or symptoms.