Abstract

Background: Due to the side effects of current therapies for osteoarthritis, alternative medical therapy using the herb Tragopogon pratensis L., which in Iranian traditional medicine has been used as a treatment option. Here, we attempted to evaluate the effect of Tragopogon Pratensis Alcoholic Extraction (TPAE) on proinflammatory cytokines in bovian synoviocyte and THP-1. Methods: To investigate the impact of Tragopogon Pratensis Alcoholic Extraction (TPAE) on proinflammatory cytokines suppression in bovine synoviocytes and THP-1, we isolated synoviocytes from radiocarpal synovial fluid. In addition, after evaluation of LC50, both cells (5 × 10⁵ cells well^-1) were incubated at 37°C in a 5% CO2 atmosphere with 90% humidity for 72 hours with TPAE (7.5 μg mL^-1 as a LC50). One set of cells was activated for 1h with LPS for RT-PCR analysis of COX-2, INOS, IL-1β, TNF-α expression and in parallel, activation of another cells set were done for 24 h. Cells supernatant were analyzed for PGE-2 and nitrite content. Results: The present study demonstrates that TPAE reduced expression of COX-2, INOS, and TNF-α in a control group and reduced expression of COX2 and INOS was significant, as was the reduction in production of NO and PGE2. Also TPAE decreased the expression of TNF-α and IL-1β in control group. Conclusions: Our results showed that the anti-inflammatory effect of TPAE was related not only to the synoviocyte cells, but also to the THP-1 that are active in the synovial membrane.