Establishment of a Mechanical Stress Load Arthritis Model in a Human Synovial Sarcoma Cell Line

Abstract

Osteoarthritis OA is a degenerative disease that occurs in joints throughout the body and includes various concomitant pathologies due to possible mechanical stress, such as destruction of cartilage, hyperplasic changes, and synovial in ammation. However, there have been few studies on the mechanical stress that is the basic cause of OA. Our goal was to establish an OA model at the cellular level, by measuring in ammatory cytokines and cartilage destruction markers that are induced after a mechanical stress load. Using a human synovial sarcoma cell line SW982 cells , we provided two types of mechanical stress load for 48 hr : shaking stress amplitude 2 mm, speed range 1,000 rpm , and the addition of hydroxyapatite 5 µg/ml into the culture medium. Then we measured the phosphorylation activity of nuclear factor NF -B transcription factor in the cell lysate, and the levels of tumor necrosis factor TNF -and interleukin IL -6 as in ammatory cytokines, and the level of matrix metalloproteinase MMP -3 as a cartilage destruction marker, released in the medium. Shaking stress signi cantly induced phosphorylation of NF-B and production of TNF-, compared with untreated controls. On the other hand, hydroxyapatite stress only increased production of TNF-. Both stresses together signi cantly induced phosphorylation of NF-B and production of TNF-, IL-6 and MMP-3 rather than a single stress load. In this study, markers related to in ammation and cartilage destruction IL-6, TNF-, and MMP-3 signi cantly increased. Therefore, we suggest that the mechanical stress load conditions used in this study might be useful as an OA model.

Comparison of Anti-Inflammatory Analgesics for Mechanical Stress-induced Inflammation in a Human Synovial Sarcoma Cell Line

“…First, stress was induced by the addition of 5 µg/ml hydroxyapatite in the form of Micro-SHAp IHM-10010 ; Sofsera Co., Ltd., Tokyo, Japan to mimic the effect of foreign bodies in the joint bone destruction . Second, mechanical load stress was induced by shaking the microplates on a mini-shaker PSU-2T ; Funakoshi Co., Ltd., Tokyo, Japan at 2 mm amplitude and 1,000 rpm as described previously 10 .…”

“…However, to the best of our knowledge, there has been no report of MS-induced inflammation in cell lines, even though MS is essential for the clinical condition of OA. Therefore, we developed an MS-induced model of arthritis that simulates fine bone fragments and motion in a human synovial sarcoma cell line SW982 10 . In the present study, we compared the effects of various anti-inflammatory analgesics at the cellular level.…”