Activation of mitogen-activated protein kinase (MAPK) enzymes in nociceptive plasticity has been extensively studied. P38 MAPK enzyme, which can be activated by cytokines, acts as a crucial intracellular regulator of environmental changes. The aim of this study was to elucidate the cellular events during arthritis-induced hyperalgesia that are mediated by interleukin-6 and p38 MAPK, and their effects on the expression of spinal mu-opioid receptors (MORs), in different stages of arthritis in male Wistar rats. Complete Freund’s adjuvant (CFA)-induced arthritis (AA) was caused by subcutaneous injection of CFA into the rats’ hindpaw. Anti-IL-6 antibody and p38 MAPK phosphorylation inhibitor were administered during 21 days of study. Spinal MOR, p38, and phosphorylated-p38 (pp38) proteins expressions were detected by Western blotting. Daily treatment with anti-IL-6 antibody and p38 MAPK phosphorylation inhibitor, SB203580, significantly decreased paw edema in AA group. Daily anti-IL-6 and SB203580 administration caused a significant reduction in hyperalgesia in the first week of the study, but increased hyperalgesia in the next 2 weeks in experimental groups compared to the AA control group. Expression of pp38 MAPK protein significantly decreased on the 3, 7, 14, and 21 days in AA+SB203580 and AA+anti-IL6 groups compared to AA group. Additionally, daily treatment with anti-IL6 antibody and SB203580 in AA group caused significantly decrease in spinal MOR expression compared to AA control group. The results of our study can confirm that activated spinal p38 MAPK enzyme may play an important role in cellular IL-6 signaling pathways in hyperalgesia variation during different stages of AA inflammation. Also, it can be suggested that at least a part of p38 MAPK effects on hyperalgesia is mediated by spinal MOR expression variation.
Arthritis CFA hyperalgesia Interleukin-6 Mu-opioid receptor p38 MAPK
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This project was supported by Research & Technology Affairs of Shahid Beheshti University of Medical Sciences.
Conflict of interest
All authors declare that they have no conflict of interests.
Abbadie C, Bhangoo S, De Koninck Y, Malcangio M, Melik-Parsadaniantz S, White FA (2009) Chemokines and pain mechanisms. Brain Res Rev 60:125–134PubMedCrossRefGoogle Scholar
Cui XY, Dai Y, Wang SL, Yamanaka H, Kobayashi K, Obata K et al (2008) Differential activation of p38 and extracellular signal regulated kinase in spinal cord in a model of bee venom-induced inflammation and hyperalgesia. Mol Pain 4:17PubMedCrossRefGoogle Scholar
Zaringhalam J, Manaheji H, Mghsoodi N, Farokhi B, Mirzaiee V (2007) Investigation of the relation between the hypothalamus-pituitary-adrenalaxis, IL-6 and hyperalgesia during rheumatoid arthritis in male rats. Physiol Pharmacol 11:130–136Google Scholar
De Jongh RF, Vissers KC, Meert TF, Booij LH, De Deyne CS, Heylen RJ (2003) The role of interleukin-6 in nociception and pain. Anesth Analg 96:1096–1103PubMedCrossRefGoogle Scholar
O’Keefe SJ, Mudgett JS, Cupo S, Parsons JN, Chartrain NA, Fitzgerald C et al (2007) Chemical genetics define the roles of p38alpha and p38beta in acute and chronic inflammation. J Biol Chem 282:34663–34671PubMedCrossRefGoogle Scholar
Svensson CI, Marsala M, Westerlund A, Calcutt NA, Campana WM, Freshwater JD et al (2003) Activation of p38 mitogen-activated protein kinase in spinal microglia is a critical link in inflammation-induced spinal pain processing. J Neurochem 86:1534–1544PubMedCrossRefGoogle Scholar
Tai YH, Liaw WH, Tao YX, Wong CS (2009) The roles of excitatory amino acids and cytokines in morphine tolerance: effect of tricyclic antidepressant amitriptyline. Open Pain J 2:64–70CrossRefGoogle Scholar
Zhang Q, Schäffer M, Elde R, Stein C (1998) Effects of neurotoxins and hindpaw inflammation on opioid receptor immunoreactivities in dorsal root ganglia. Neuroscience 85:281–291PubMedCrossRefGoogle Scholar
Zollner C, Shaqura MA, Bopaiah CP, Mousa S, Stein C, Schafer M (2003) Painful inflammation induced increase in mu-opioid receptor binding and G-protein coupling in primary afferent neurons. Mol Pharmacol 64:202–210PubMedCrossRefGoogle Scholar
Boyle DL, Jones TL, Hammaker D, Svensson CI, Rosengren S, Albani S et al (2006) Regulation of peripheral inflammation by spinal p38 MAP kinase in rats. PLoS Med 3:1616–1624CrossRefGoogle Scholar
Chae HJ, Byun JO, Chae SW, Kim HM, Choi HI, Pae HO et al (2005) p38 MAPK and NF-kappaB on IL-6 release in human gingival fibroblasts. Immunopharm Immunotoxicol 27:631–646CrossRefGoogle Scholar
Zimmermann M (1983) Ethical guidelines for investigations of experimental pain on conscious animals. Pain 16:109–110PubMedCrossRefGoogle Scholar
Cicala C, Ianaro A, Fiorucci S, Calignano A, Bucci M, Gerli R et al (2000) NO-naproxen modulates inflammation, nociception and downregulates T cell response in rat freund’s adjuvant arthiritis. Br J Pharmacol 130:490–497CrossRefGoogle Scholar
Taniguchi N, Kanai S, Kawamoto M, Endo H, Higashino H (2004) Study on application of static magnetic field for adjuvant arthritis rats. Evid Based Complement Alternat Med 1:187–191PubMedCrossRefGoogle Scholar
Agarwal S, Misra R, Aggarwal A (2010) Induction of metalloproteinases expression by TLR ligands in human fibroblast like synoviocytes from juvenile idiopathic arthritis patients. Indian J Med Res 131:771–779PubMedGoogle Scholar
Liang B, Song Z, Wu B, Gardner D, Shealy D, Song XY et al (2009) Evaluation of anti-IL-6 monoclonal antibody therapy using murine type II collagen-induced arthritis. J Inflamm (Lond) 6:10CrossRefGoogle Scholar
Serada S, Fujimoto M, Mihara M, Koike N, Ohsugi Y, Nomura S et al (2008) IL-6 blockade inhibits the induction of myelin antigen-specific Th17 cells and Th1 cells in experimental autoimmune encephalomyelitis. Proc Natl Acad Sci USA 105:9041–9046PubMedCrossRefGoogle Scholar
Obata K, Noguchi K (2004) MAPK activation in nociceptive neurons and pain hypersensitivity. Life Sci 74:2643–2653PubMedCrossRefGoogle Scholar
Hargreaves K, Dubner R, Brown F, Flores C, Joris J et al (1988) A new and sensitive method for measuring thermal nociception in cutaneous hyperalgesia. Pain 32:77–88PubMedCrossRefGoogle Scholar
Billiau A, Matthys P (2001) Modes of action of Freund’s adjuvants in experimental models of autoimmune diseases. J Leukoc Biol 70:849–860PubMedGoogle Scholar
Cunha JM, Cunha FQ, Poole S, Ferreira SH (2000) Cytokine-mediated inflammatory hyperalgesia limited by interleukin-1 receptor antagonist. Br J Pharmacol 130:1418–1424PubMedCrossRefGoogle Scholar
Sehga MI, Smith H, Manchikanti L (2011) Peripherally acting opioids and clinical implications for pain control. Pain Physician 14:249–258Google Scholar
Möller B, Villiger PM (2006) Inhibition of IL-1, IL-6, and TNF-alpha in immune-mediated inflammatory diseases. Springer Semin Immunopathol 27:391–408PubMedCrossRefGoogle Scholar
Liang Y, Fang JQ, Du JY, Fang JF (2012) Effect of electroacupuncture on activation of p38MAPK in spinal dorsal horn in rats with complete Freund’s adjuvant-induced inflammatory pain. Evid Based Complement Alternat Med 2012:568273PubMedGoogle Scholar
Winzen R, Kracht M, Ritter B, Wilhelm A, Chen CY, Shyu AB et al (1999) The p38 MAP kinase pathway signals for cytokine-induced mRNA stabilization via MAP kinase-activated protein kinase 2 and an AU-rich region-targeted mechanism. EMBO J 18:4969–4980PubMedCrossRefGoogle Scholar
Finn AK, Whistler JL (2001) Endocytosis of the mu opioid receptor reduces tolerance and a cellular hallmark of opiate withdrawal. Neuron 32:761–763CrossRefGoogle Scholar