Proceedings of The Physiological Society

Europhysiology 2018 (London, UK) (2018) Proc Physiol Soc 41, PCB248

Poster Communications

Effects of Salmon Calcitonin and Omega-3 Fatty Acids on some Biochemical Parameters in Induced Diabetic-Knee Osteoarthritic Rats

L. A. Olayaki1, W. J. Adeyemi1

1. Physiology, University of Ilorin, Ilorin, Kwara, Nigeria.

Early evidence on the association between type 2 diabetes (T2D) and osteoarthritis (OA) dated back to the 1960s (Waine et al. 1961). Studies revealed that diabetes has an independent role in the pathogenesis and advancement, while there was an increased risk of diabetes among OA patients (King et al. 2013; Rahman et al. 2014). However, there are controversies on the optimum therapy in diabetic condition. The study was carried out to determine the effects of salmon calcitonin (Sct) and/or omega - 3 fatty acids (N-3) in induced diabetic-knee osteoarthritic rats. The 35 male Wistar rats that were used for this study were randomly divided into 7 groups (n=5 rats) which include: Group 1 - Normal control; Group 2 - Diabetic-Osteoarthritic (D + OA) control; Group 3 - D + OA + N-3 (200mg/kg, p.o. once daily); Group 4 - D + OA + Low Salmon (Sct.Lw - 2.5IU/kg, i.m. once daily); Group 5 - D + OA + High Salmon (Sct.Hi - 5.0IU/kg, i.m. once daily); Group 6 - D + OA + N-3 + Sct.Lw; and Group 7 - D + OA + N-3 + Sct.Hi. Diabetes was induced in overnight fasted rats with streptozotocin (65mg/kg, i.p.) in citrate buffer (pH - 4.5). This was administered 15 minutes after the administration of nicotinamide (110mg/kg, i.p.) in normal saline (Satheesh & Pari, 2008). Knee OA was induced with 4mg monosodium iodoacetate in 40µl of sterile saline. The resultant solution was injected (using a 27-gauge needle) intra-articularly (i.a.) through the patellar ligament of the rats' left knee joint, while the rats in the normal control group were injected with citrate buffer (0.1ml, i.p.) and sterile saline (40µl, i.a.), all under sodium pentobarbital (40mg/kg, i.p.) anaesthesia (Orita et al. 2011). OA was induced about 12hours after the induction of diabetic condition. Treatments with Sct and N-3 started 9 days after the induction of the diabetic and osteoarthritic states, and they lasted for 28 days. The induced diabetic-knee osteoarthritic featured significant elevations in total alkaline phosphatase (TALP), malondialdehyde, c-telopeptide of type I collagen (CTX-1), and collagen type 2 alpha 1 (C2M) levels; but, significant decreases in catalase, glutathione peroxidase (GPX), total bilirubin (TB), and total antioxidant capacity (TAC). The hyperglycaemic effect of Sct was significantly abated when it was co-administered with N-3. Moreover, Sct had a dose-specific effect, and an additive action with N-3 in reducing malondialdehyde and LDH, and in elevating TB and TAC. However, Sct demonstrated non-dose graded effects, and non-additive actions with N-3 in increasing SOD, catalase and GPX, and in decreasing TALP, CTX-I and C2M. In this study, there was evidence for the additive, non-additive and antagonistic effects of both Sct and N-3, and the combined administration of Sct and N-3 could offer better therapeutic actions in diabetic-knee osteoarthritis.

Where applicable, experiments conform with Society ethical requirements