OBJECTIVE: Osteoarthritis (OA) is an age-related disease that occurs in various joints due to mechanical stress. Inflammation occurs at synovial membrane in early stage, and cartilage wears and joint function breaks as it progresses. In this study, we evaluated the usefulness of the mechanical stress loaded OA model in cultured human synovial sarcoma cell line by using the anti-inflammatory agents which commonly used in Japan to OA clinical treatment.
METHODS: Using a human synovial sarcoma cell line (SW982), we provided two types of mechanical stress loads for 48 hr: shaking stress (amplitude 2 mm, speed range 1000 rpm), and the addition of hydroxyapatite (HA: 5 µg/ml) into the culture medium. We added the anti-inflammatory agents into the medium before shake, too. Which were acetaminophen (Ace), 10 µg/ml of ketoprofen (Ket), 1 µg/ml of celecoxib (Cel), 10 µg/ml of triamcinolone acetonide (Tri), 1 µg/ml of dexamethasone (Dex) and inoculated rabbits inflammatory skin extract extract containing preparation (Vac) 1.2 * 10-3 NU/ml. We measured TNF-α, IL-6, MMP-3, PGE2 levels, NFκB and MAPKs activity, by using ELISA method.
RESULTS: Almost all measurement items increased by mechanical stress load. PGE2 was significantly suppressed by pretreatment with Ket and Cel, nonsteroidal anti-inflammatory drugs (NSAIDs). However, there was no change in the production of other inflammatory cytokines.In pretreatment of Tri and Dex, a steroidal anti-inflammatory drug (Steroid), both significantly prevented TNF-α production. Tri significantly inhibited IL-6, MMP-3 production and NF-κB activity, however, Dex did not change. Significant suppression was observed with TNF-α, MMP-3 production, NFκB, JNK activity in the pretreatment with Ace, antipyretic analgesic, but no change was observed in the production of PGE2 and IL-6. TNF-α, IL-6, MMP-3 levels and NFκB activity were significant inhibited by pretreatment with Vac, a therapeutic agent for descending pain suppressing system activation stimulant (non-opioid, non-cyclooxygenase inhibition).
CONCLUSION: In this study, mechanism of action was able to demonstrate effects using known NSAIDs and steroids. These results suggest that this mechanical stress load may be useful as a OA model.
