Background Osteoarthritis (OA) is a chronic disease in the joints. One of the proinflammatory cytokines that is thought to have a major role in the inflammatory process, the emergence of pain, and cartilage damage in OA is tumor necrosis factor α (TNF-α). Meloxicam is a nonsteroidal anti-inflammatory drug class of drugs that is relatively selective in inhibiting the activity of cyclooxygenase 2 (COX-2) formation. This study is conducted to prove the change in TNF-α level in the use of meloxicam with model in animals suffering from OA. Methods The OA rat model was induced with sodium monoiodoacetate intra-articularly. Rats were divided into 5 groups: negative control group, positive control group, and treatment groups with various doses of meloxicam. Hyperalgesia effect was evaluated using a warm plate test, and TNF-α level was determined using enzyme-linked immunosorbent assay. Results The treatment groups that received meloxicam at a dose of 1.0, 3.0, or 10.0 mg/kg body weight (BW) did not show significant differences in rat knee joint diameter (p = 0.99), but showed a significant difference in sensitivity to heat stimulation (p = 0.02) compared to the control group. Osteoarthritis rats experienced a significant reduction in TNF-α level after being given meloxicam at a dose of 10 mg/kg BW compared with the control group. This shows that the 10 mg/kg BW of meloxicam is a potential dose in reducing the TNF-α level in OA rat models. Conclusions Based on these data, it can be concluded that the inhibition of pain and the development of OA by meloxicam in animal models may be assigned to a decreased level of TNF-α.
Keywords: TNF-α; hyperalgesia; inflammatory pain; meloxicam; osteoarthritis animal model.