Résumé
Interleukin [IL-6] is known to cause pro-and anti-inflammatory effects during different stages of inflammation. The purpose of this study was to elucidate the effects of IL-6 on hyperalgesia, edema and the changes in the spinal mu opioid receptor expression during different stages of complete Freund's adjuvant [CFA]-induced arthritis [AA] in rats. In this study, AA was induced by a single subcutaneous injection of CFA into rats' hindpaw. The rats with arthritis were divided into four groups, each consisted of three subgroups [n=6]. Anti-IL-6 was administered either daily or weekly during the 21-day study period. Spinal mu-opioid receptor [mOR] expression was detected by Western blotting. Daily treatment with an anti-IL-6 antibody significantly decreased the paw edema in the AA group compared to the control one [P=0.001], but daily and weekly anti-IL-6 administrations significantly increased the hyperalgesia in the antibody-treated group on the 14th and 21st days post-treatment [P=0.001, P=0.01, respectively]. The administration of IL-6 antibody not only increased hyperalgesia in a time-dependent manner, but also caused a significant reduction in the spinal mOR expression on the 14th and 21st days post-CFA injection [P=0.01, P=0.001, respectively]. Results can indicate the importance of a time-dependent relationship between the serum IL-6 level and hyperalgesia during the AA. Moreover, the results suggest that the stages of inflammation in AA must be considered for anti-hyperalgesic and anti-inflammatory interventions via anti-IL-6 antibody treatment
Résumé
Inflammatory symptoms, hyperalgesia and edema, as a physiologic responses for stimulus can mediate via different mediators such as cytokines. Medicinal plants are an important source of substances which are claimed to induce anti-inflammatory effects. Regarding to these and on account of the Interlukine-6 roles in hyperalgesia and edema induction, the aim of this study explained to investigation of the pre-treatment effects of Achillea santolina and Stachys athorecalyx extracts on inflammation which induced by CFA in male Wistar rats. Methanolic and defatted extractions were done on aerial parts of the both plants. Achillea santolina and Stachys athorecalyx 50, 100 and 200 mg/kg doses of extracts were selected for treatment. Results indicated that pre-treatment with defatted and methanolic extracts of S. athorecalyx significantly decrease CFA-induced hyperalgesia and edema dose-dependently. At same situation only methanolic extract of A. santolina was effective in inflammatory signs reduction. It can concluded that A. santolina and S. athorecalyx extracts can be effective candidate for pre-treatment of inflammation, but the effective substances of them are different and need to be more investiged