• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.10
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• pp.1510-1518
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• 2014

This study investigated the effects of calcium citrate on papain-induced osteoarthritis in C57BL/6J mice. Osteoarthritis was induced by injecting $6{\mu}L$ of papain into the knee joints of mice. Calcium citrate was made by crushing the centrifuged precipitate after reacting 0.5 M citric acid with 1 kg of oyster shell extract. The mice were divided into five groups (n=8). The normal group was untreated, whereas the papain group was induced to have osteoarthritis and treated with $200{\mu}L$ of water per day. The papain+DS group was treated with diclofenac sodium. The papain+calcium citrate groups were treated with calcium citrate at 150 and 300 mg/kg/bw for 28 days. Proteoglycan contents in articular cartilages were measured by safranin O/fast green staining and hematoxylin & eosin staining. Histopathological changes in cartilages were analyzed by the Rudolphi score approach. Contents of pro-inflammatory cytokines including TNF-${\alpha}$, IL-$1{\beta}$ and IL-6 in plasma, were measured by the ELISA method. Body weights among the treated groups were not significantly different compared with that of the normal group. Cartilage loss and joint instability in the calcium citrate group improved significantly (P<0.05) in a dose-dependent manner compared with the papain group. Further, proteoglycan content of the calcium citrate group was considerably (P<0.05) higher than that of the papain group. Osteoarthritis scores in the calcium citrate group were considerably (P<0.05) reduced compared with the papain group. In the group treated with calcium citrate, contents of TNF-${\alpha}$, IL-$1{\beta}$ and IL-6 in plasma were significantly (P<0.05) reduced in a dose-dependent manner in comparison with the normal group. Based on these results, we suggest that calcium citrate is effective for treatment of osteoarthritis.