THE ROLE OF DIABETES ON EXPERIMENTAL ARTHRITIS: ANALGESIC, ANTI-INFLAMMATORY AND ADVERSE EFFECTS OF NSAID

Diabetes is a serious and increasing global health burden. Recent studies show a clear association between diabetes and osteoarthritis (OA). Nearly half (47.3%) of patients with diabetes have some form of OA. The common treatment of OA involves nonsteroidal anti-inflammatory drugs (NSAIDs), particularly ibuprofen, which is thought to be the safest NSAID available. Nevertheless, recent studies are showing increased cardiovascular risk and exacerbation of infections associated with its use. The aim of the present study is to investigate the role of diabetes on experimental adjuvant arthritis and the effect of ibuprofen. Male Wistar rats were used for the experiments. Diabetes was induced in rats by a single application of streptozotocin (STZ, 75 mg/kg, i.p.) and confirmed by blood glucose monitoring three days afterwards. Adjuvant arthritis was induced by intraplantar injection of complete Freund's adjuvant (CFA). Hind paw volume was determined by plethysmometry. Mechanical hyperalgesia was measured by paw pressure test. Rats were treated with ibuprofen 20 and 40 mg/kg i.p. It was found that the late phase of adjuvant arthritis was more pronounced in diabetic rats. PPT showed a significant decrease in the paw withdrawal threshold in diabetic rats. Ibuprofen increases the pain threshold in the early and in the late phase of CFA-induced arthritis in nondiabetic and diabetic rats. Diabetic rats showed more severe symptoms of CFA-induced arthritis compared with nondiabetic supporting the recent findings questioning the effect of diabetes on osteoarthritis severity.