Effects of single or combined administration of salmon calcitonin and omega-3 fatty acids vs. diclofenac sodium in sodium monoiodoacetate-induced knee osteoarthritis in male Wistar rats.

BACKGROUND: There is a continuous search for a better therapy in osteoarthritis (OA) management. Therefore, this study investigated the effects of salmon calcitonin (Sct) and/or omega-3 fatty acids (N-3) relative to diclofenac sodium (DF) in induced knee osteoarthritic male Wistar rats. METHODS: The 40 rats that were used in this study were divided into 8 groups (n=5 rats), viz: Normal control; OA control; OA+N-3; OA+Low dose of Sct (Sct.Lw); OA+High dose of Sct (Sct.Hi); OA+N-3+SCt.Lw; OA+N-3+Sct.Hi; and, OA+DF. OA was induced with 4 mg of sodium monoiodoacetate in 40 µL of saline. The solution was injected into the left knee joint space of anaesthetised rats. Sct was administered at 2.5 and 5.0 IU/kg b.w. (im), whereas N-3 and DF were administered at 200 and 1 mg/kg b.w. (p.o.), respectively. Treatments commenced 9 days after the induction of OA, and they lasted for 28 days. RESULTS: Sct and/or N-3 significantly reduced c-telopeptide of type 1 collagen (CTX-1), collagen type 2 α-1 (C2M), malondialdehyde (MDA), uric acid (UA), and interleukin-6 (IL-6), but, significantly increased superoxide dismutase (SOD) after OA induction. Both therapies had additive effects on C2M, MDA, SOD, and catalase (CAT), but, non-additive actions on UA, IL-6, and CTX-1. Like the Sct and N-3, DF significantly reduced CTX-1, C2M, UA, and IL-6. However, it had no significant effect on SOD and MDA, even though it significantly reduced CAT activity. None of the therapies had significant effect on total alkaline phosphatase activity, except N-3+Sct.Lw. CONCLUSIONS: The combined, and sometimes the single administration of Sct and N-3 proved to be better therapies in OA management than DF.