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Activation of GRs–Akt–nNOs–NR2B signaling pathway by second dose GR agonist contributes to exacerbated hyperalgesia in a rat model of radicular pain

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Abstract

Central Akt, neuronal nitric oxide synthase (nNOS) and N-methyl-d-aspartate receptor subunit 2B (NR2B) play key roles in the development of neuropathic pain. Here we investigate the effects of glucocorticoid receptors (GRs) on the expression and activation of spinal Akt, nNOS and NR2B after chronic compression of dorsal root ganglia (CCD). Thermal hyperalgesia test and mechanical allodynia test were used to measure rats after intrathecal injection of GR antagonist mifepristone or GR agonist dexamethasone for 21 days postoperatively. Expression of spinal Akt, nNOS, NR2B and their phosphorylation state after CCD was examined by western blot. The effects of intrathecal treatment with dexamethasone or mifepristone on nociceptive behaviors and the corresponding expression of Akt, nNOS and NR2B in spinal cord were also investigated. Intrathecal injection of mifepristone or dexamethasone inhibited PWMT and PWTL in CCD rats. However, hyperalgesia was induced by intrathecal injection of dexamethasone on days 12 to 14 after surgery. Treatment of dexamethasone increased the expression and phosphorylation levels of spinal Akt, nNOS, GR and NR2B time dependently, whereas administration of mifepristone downregulated the expression of these proteins significantly. GRs activated spinal Akt–nNOS/NR2B pathway play important roles in the development of neuropathic pain in a time-dependent manner.

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References

  1. Takeda K, Sawamura S, Sekiyama H, Tamai H, Hanaoka K (2004) Effect of methylprednisolone on neuropathic pain and spinal glial activation in rats. Anesthesiology 100:1249–1257

    Article  CAS  PubMed  Google Scholar 

  2. Arden NK, Price C, Reading I et al (2005) A multicentre randomized controlled trial of epidural corticosteroid injections for sciatica: the WEST study. Rheumatology (Oxford) 44:1399–1406

    Article  CAS  Google Scholar 

  3. Gu X, Wang S, Yang L et al (2007) Time-dependent effect of epidural steroid on pain behavior induced by chronic compression of dorsal root ganglion in rats. Brain Res 1174:39–46

    Article  PubMed Central  CAS  PubMed  Google Scholar 

  4. Cintra A, Molander C, Fuxe K (1993) Colocalization of Fos- and glucocorticoid receptor-immunoreactivities is present only in a very restricted population of dorsal horn neurons of the rat spinal cord after nociceptive stimulation. Brain Res 632:334–338

    Article  CAS  PubMed  Google Scholar 

  5. Hafezi-Moghadam A, Simoncini T, Yang Z et al (2002) Acute cardiovascular protective effects of corticosteroids are mediated by non-transcriptional activation of endothelial nitric oxide synthase. Nat Med 8:473–479

    Article  PubMed Central  CAS  PubMed  Google Scholar 

  6. Limbourg FP, Liao JK (2003) Nontranscriptional actions of the glucocorticoid receptor. J Mol Med 81:168–174

    PubMed Central  CAS  PubMed  Google Scholar 

  7. Limbourg FP, Huang Z, Plumier JC et al (2002) Rapid nontranscriptional activation of endothelial nitric oxide synthase mediates increased cerebral blood flow and stroke protection by corticosteroids. J Clin Invest 110:1729–1738

    Article  PubMed Central  CAS  PubMed  Google Scholar 

  8. Leis H, Page A, Ramírez A et al (2004) Glucocorticoid receptor counteracts tumorigenic activity of Akt in skin through interference with the phosphatidylinositol 3-kinase (PI3K) signaling pathway. Mol Endocrinol 18:303–311

    Article  CAS  PubMed  Google Scholar 

  9. Opazo P, Watabe AM, Grant SG et al (2003) Phosphatidylinositol 3-kinase regulates the induction of long-term potentiation through extracellular signal-related kinase-independent mechanisms. J Neurosci 23:3679–3688

    CAS  PubMed  Google Scholar 

  10. Mizuno M, Yamada K, Takei N et al (2003) Phosphatidylinositol 3-kinase: a molecule mediating BDNF-dependent spatial memory formation. Mol Psychiatry 8:217–224

    Article  CAS  PubMed  Google Scholar 

  11. Sun RQ, Tu YJ, Yan JY et al (2006) Activation of protein kinase B/Akt signaling pathway contributes to mechanical hypersensitivity induced by capsaicin. Pain 120:86–96

    Article  CAS  PubMed  Google Scholar 

  12. Xu JT, Tu HY, Xin WJ, Liu XG, Zhang GH, Zhai CH (2007) Activation of phosphatidylinositol 3-kinase and protein kinase B/Akt in dorsal root ganglia and spinal cord contributes to the neuropathic pain induced by spinal nerve ligation in rats. Exp Neurol 206:269–279

    Article  CAS  PubMed  Google Scholar 

  13. Sun RQ, Tu YJ, Yan JY et al (2007) Activation of protein kinase B/Akt in the periphery contributes to pain behavior induced by capsaicin in rats. Neuroscience 144:286–294

    Article  CAS  PubMed  Google Scholar 

  14. Cizkova D, Lukacova N, Marsala M et al (2002) Neuropathic pain is associated with alterations of nitric oxide synthase immunoreactivity and catalytic activity in dorsal root ganglia and spinal dorsal horn. Brain Res Bull 58:161–171

    Article  CAS  PubMed  Google Scholar 

  15. Mabuchi T, Matsumura S, Okuda-Ashitaka E et al (2003) Attenuation of neuropathic pain by the nociceptin/orphanin FQ antagonist JTC-801 is mediated by inhibition of nitric oxide production. Eur J Neurosci 17:1384–1392

    Article  PubMed  Google Scholar 

  16. Guan Y, Yaster M, Raja SN, Tao YX (2007) Genetic knockout and pharmacologic inhibition of neuronal nitric oxide synthase attenuate nerve injury-induced mechanical hypersensitivity in mice. Mol Pain 3:29

    Article  PubMed Central  PubMed  Google Scholar 

  17. Cunha TM, Roman-Campos D, Lotufo CM et al (2010) Morphine peripheral analgesia depends on activation of the PI3Kγ/AKT/nNOS/NO/KATP signaling pathway. Proc Natl Acad Sci USA 107:4442–4447

    Article  PubMed Central  CAS  PubMed  Google Scholar 

  18. Husi H, Grant SG (2001) Proteomics of the nervous system. Trends Neurosci 24:259–266

    Article  CAS  PubMed  Google Scholar 

  19. Momiyama A (2000) Distinct synaptic and extrasynaptic NMDA receptors identified in dorsal horn neurones of the adult rat spinal cord. J Physiol 523:621–628

    Article  PubMed Central  CAS  PubMed  Google Scholar 

  20. Karlsson U, Sjödin J, Angeby Möller K, Johansson S, Wikström L, Näsström J (2002) Glutamate-induced currents reveal three functionally distinct NMDA receptor populations in rat dorsal horn—effects of peripheral nerve lesion and inflammation. Neuroscience 112:861–868

    Article  CAS  PubMed  Google Scholar 

  21. Qu XX, Cai J, Li MJ et al (2009) Role of the spinal cord NR2B-containing NMDA receptors in the development of neuropathic pain. Exp Neurol 215:298–307

    Article  CAS  PubMed  Google Scholar 

  22. Abe T, Matsumura S, Katano T et al (2005) Fyn kinase-mediated phosphorylation of NMDA receptor NR2B subunit at Tyr1472 is essential for maintenance of neuropathic pain. Eur J Neurosci 22:1445–1454

    Article  PubMed  Google Scholar 

  23. Yaksh TL, Rudy TA (1976) Chronic catheterization of the spinal subarachnoid space. Physiol Behav 17:1031–1036

    Article  CAS  PubMed  Google Scholar 

  24. Gu X, Yang L, Wang S et al (2008) A rat model of radicular pain induced by chronic compression of lumbar dorsal root ganglion with SURGIFLO. Anesthesiology 108:113–121

    Article  PubMed  Google Scholar 

  25. Obata K, Yamanaka H, Kobayashi K et al (2004) Role of mitogen-activated protein kinase activation in injured and intact primary afferent neurons for mechanical and heat hypersensitivity after spinal nerve ligation. J Neurosci 24:10211–10222

    Article  CAS  PubMed  Google Scholar 

  26. Wang S, Lim G, Zeng Q et al (2004) Expression of central glucocorticoid receptors after peripheral nerve injury contributes to neuropathic pain behaviors in rats. J Neurosci 24:8595–8605

    Article  CAS  PubMed  Google Scholar 

  27. Tal M, Bennett GJ (1994) Extra-territorial pain in rats with a peripheral mononeuropathy: mechano-hyperalgesia and mechano-allodynia in the territory of an uninjured nerve. Pain 57:375–382

    Article  CAS  PubMed  Google Scholar 

  28. Hargreaves K, Dubner R, Brown F, Flores C, Joris J (1988) A new and sensitive method for measuring thermal nociception in cutaneous hyperalgesia. Pain 32:77–88

    Article  CAS  PubMed  Google Scholar 

  29. Tanabe M, Nagatani Y, Saitoh K et al (2009) Pharmacological assessments of nitric oxide synthase isoforms and downstream diversity of NO signaling in the maintenance of thermal and mechanical hypersensitivity after peripheral nerve injury in mice. Neuropharmacology 56:702–708

    Article  CAS  PubMed  Google Scholar 

  30. Chacur M, Matos RJ, Alves AS et al (2010) Participation of neuronal nitric oxide synthase in experimental neuropathic pain induced by sciatic nerve transection. Braz J Med Biol Res 43:367–376

    Article  CAS  PubMed  Google Scholar 

  31. Takasaki I, Kurihara T, Saegusa H et al (2005) Effects of glucocorticoid receptor antagonists on allodynia and hyperalgesia in mouse model of neuropathic pain. Eur J Pharmacol 524:80–83

    Article  CAS  PubMed  Google Scholar 

  32. Ma ZL, Zhang W, Gu XP, Yang WS, Zeng YM (2007) Effects of intrathecal injection of prednisolone acetate on expression of NR2B subunit and nNOS in spinal cord of rats after chronic compression of dorsal root ganglia. Ann Clin Lab Sci 37:349–355

    CAS  PubMed  Google Scholar 

  33. Reuss MH, Reuss S (2001) Nitric oxide synthase neurons in the rodent spinal cord: distribution, relation to substance P fibers, and effects of dorsal rhizotomy. Chem Neuroanat 21:181–196

    Article  CAS  Google Scholar 

  34. Spaccarelli KC (1996) Lumbar and caudal epidural corticosteroid injections. Mayo Clin Proc 71:169–178

    Article  CAS  PubMed  Google Scholar 

  35. Arden NK, Price C, Reading I et al (2005) A multicentre randomized controlled trial of epidural corticosteroid injections for sciatica: the WEST study. Rheumatology (Oxford) 44:1306–1399

    Article  Google Scholar 

  36. Price C, Arden N, Coglan L et al (2005) Cost-effectiveness and safety of epidural steroids in the management of sciatica. Health Technol Assess 9:1–58

    Article  CAS  PubMed  Google Scholar 

  37. Armon C, Argoff CE, Samuels J et al (2007) Assessment: use of epidural steroid injections to treat radicular lumbosacral pain: report of the therapeutics and technology assessment subcommittee of the American Academy of Neurology. Neurology 68:723–729

    Article  CAS  PubMed  Google Scholar 

  38. Li H, Xie W, Strong JA, Zhang JM (2007) Systemic antiinflammatory corticosteroid reduces mechanical pain behavior, sympathetic sprouting, and elevation of proinflammatory cytokines in a rat model of neuropathic pain. Systemic antiinflammatory corticosteroid reduces mechanical pain behavior, sympathetic sprouting, and elevation of proinflammatory cytokines in a rat model of neuropathic pain. Anesthesiology 107:469–477

    Article  PubMed Central  CAS  PubMed  Google Scholar 

  39. Beaudry F, Girard C, Vachon P (2007) Early dexamethasone treatment after implantation of a sciatic-nerve cuff decreases the concentration of substance P in the lumbar spinal cord of rats with neuropathic pain. Can J Vet Res 71:90–97

    PubMed Central  CAS  PubMed  Google Scholar 

  40. Wang S, Lim G, Zeng Q et al (2005) Central glucocorticoid receptors modulate the expression and function of spinal NMDA receptors after peripheral nerve injury. J Neurosci 25:488–495

    Article  PubMed  Google Scholar 

  41. Wang S, Lim G, Yang L et al (2006) Downregulation of spinal glutamate transporter EAAC1 following nerve injury is regulated by central glucocorticoid receptors in rats. Pain 120:78–85

    Article  CAS  PubMed  Google Scholar 

  42. Wang S, Lim G, Mao J et al (2007) Central glucocorticoid receptors regulate the upregulation of spinal cannabinoid-1 receptors after peripheral nerve injury in rats. Pain 131:96–105

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgments

This research was supported by the National Natural Foundation of China (30872439/c160202, 81171047/H0903, 81171048, 81070892), Natural Science Fund of Jiangsu Province (BK2009031, BK2010105, XK201140), the Grant from the department of health of Jiangsu Province (H200943, RC2011006, 2010117).

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Correspondence to Zhengliang Ma or Xiaoping Gu.

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Jing Zhang and Wei Zhang have contributed equally to this work.

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Zhang, J., Zhang, W., Sun, Y. et al. Activation of GRs–Akt–nNOs–NR2B signaling pathway by second dose GR agonist contributes to exacerbated hyperalgesia in a rat model of radicular pain. Mol Biol Rep 41, 4053–4061 (2014). https://doi.org/10.1007/s11033-014-3274-7

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  • DOI: https://doi.org/10.1007/s11033-014-3274-7

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