Advertisement

Electroacupuncture Increases CB2 Receptor Expression on Keratinocytes and Infiltrating Inflammatory Cells in Inflamed Skin Tissues of Rats

      Abstract

      Endogenous cannabinoids and peripheral cannabinoid CB2 receptors (CB2Rs) are involved in the antinociceptive effect of electroacupuncture (EA) on inflammatory pain. However, it remains unclear about how EA affects the expression and distribution patterns of peripheral CB2Rs in inflamed skin tissues. To study this, inflammatory pain was induced by local injection of complete Freund's adjuvant into the hindpaw of rats. The mRNA and protein levels of CB2Rs were quantified by using RTPCR and Western blotting, respectively. The distribution of CB2Rs on keratinocytes and immune cells recruited to the inflamed skin tissues was determined by using double-immunofluorescence labeling. Induction of tissue inflammation significantly increased the mRNA and protein levels of CB2Rs in the skin tissue. Also, both 2 Hz and 100 Hz EA, applied to GB30 and GB34, significantly increased the mRNA and protein levels of CB2Rs in inflamed tissues compared to the sham EA group. CB2Rimmunoreactivities were mainly distributed in keratinocytes, macrophages, and T-lymphocytes in the epidermis and dermis of the inflamed skin tissue. Inflammation caused a significant increase in the number of CB2R-immunoreactive keratinocytes, macrophages, and T-lymphocytes. Furthermore, compared to the sham EA group, EA at 2 or 100 Hz significantly increased the number of keratinocytes, macrophages, and T-lymphocytes with CB2R-immunoreactivity in the inflamed skin tissue. Therefore, our findings suggest that EA is associated with upregulation of local CB2Rs in the inflamed skin tissue. EA primarily potentiates the expression of CB2Rs on keratinocytes and infiltrating inflammatory cells at the site of inflammation.

      Perspective

      This study shows that electroacupuncture increases the CB2 receptor expression on keratinocytes and infiltrating inflammatory cells in inflammatory skin tissues. This finding provides new evidence showing the potential role of CB2 receptors in the analgesic effect of acupuncture on inflammatory pain.

      Key words

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'

      Subscribe:

      Subscribe to The Journal of Pain
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect

      References

        • Beltramo M.
        • Stella N.
        • Calignano A.
        • Lin S.Y.
        • Makriyannis A.
        • Piomelli D.
        Functional role of high-affinity anandamide transport, as revealed by selective inhibition.
        Science. 1997; 277: 1094-1097
        • Casanova M.L.
        • Blazquez C.
        • Martinez-Palacio J.
        • Villanueva C.
        • Fernandez-Acenero M.J.
        • Huffman J.W.
        • Jorcano J.L.
        • Guzman M.
        Inhibition of skin tumor growth and angiogenesis in vivo by activation of cannabinoid receptors.
        J Clin Invest. 2003; 111: 43-50
        • Chen L.
        • Zhang J.
        • Li F.
        • Qiu Y.
        • Wang L.
        • Li Y.H.
        • Shi J.
        • Pan H.L.
        • Li M.
        Endogenous anandamide and cannabinoid receptor-2 contribute to electroacupuncture analgesia in rats.
        J Pain. 2009; 10: 732-739
        • Cook C.D.
        • Moore K.I.
        Effects of sex, hindpaw injection site and stimulus modality on nociceptive sensitivity in arthritic rats.
        Physiol Behav. 2006; 87: 552-562
        • Damoiseaux J.G.
        • Dopp E.A.
        • Calame W.
        • Chao D.
        • MacPherson G.G.
        • Dijkstra C.D.
        Rat macrophage lysosomal membrane antigen recognized by monoclonal antibody ED1.
        Immunology. 1994; 83: 140-147
        • Elmes S.J.
        • Jhaveri M.D.
        • Smart D.
        • Kendall D.A.
        • Chapman V.
        Cannabinoid CB2 receptor activation inhibits mechanically evoked responses of wide dynamic range dorsal horn neurons in naive rats and in rat models of inflammatory and neuropathic pain.
        Eur J Neurosci. 2004; 20: 2311-2320
        • Facci L.
        • Dal Toso R.
        • Romanello S.
        • Buriani A.
        • Skaper S.D.
        • Leon A.
        Mast cells express a peripheral cannabinoid receptor with differential sensitivity to anandamide and palmitoylethanolamide.
        Proc Natl Acad Sci U S A. 1995; 92: 3376-3380
        • Fu X.
        • Zhu Z.H.
        • Wang Y.Q.
        • Wu G.C.
        Regulation of proinflammatory cytokines gene expression by nociceptin/orphanin FQ in the spinal cord and the cultured astrocytes.
        Neuroscience. 2007; 144: 275-285
        • Galiegue S.
        • Mary S.
        • Marchand J.
        • Dussossoy D.
        • Carriere D.
        • Carayon P.
        • Bouaboula M.
        • Shire D.
        • Le Fur G.
        • Casellas P.
        Expression of central and peripheral cannabinoid receptors in human immune tissues and leukocyte subpopulations.
        Eur J Biochem. 1995; 232: 54-61
        • Giblin G.M.
        • O'Shaughnessy C.T.
        • Naylor A.
        • Mitchell W.L.
        • Eatherton A.J.
        • Slingsby B.P.
        • Rawlings D.A.
        • Goldsmith P.
        • Brown A.J.
        • Haslam C.P.
        • Clayton N.M.
        • Wilson A.W.
        • Chessell I.P.
        • Wittington A.R.
        • Green R.
        Discovery of 2-[(2,4-dichlorophenyl)amino]-N-[(tetrahydro-2H-pyran-4-yl)methyl]-4-(trifluoromethyl)-5-pyrimidinecarboxamide, a selective CB2 receptor agonist for the treatment of inflammatory pain.
        J Med Chem. 2007; 50: 2597-2600
        • Hanus L.
        • Breuer A.
        • Tchilibon S.
        • Shiloah S.
        • Goldenberg D.
        • Horowitz M.
        • Pertwee R.G.
        • Ross R.A.
        • Mechoulam R.
        • Fride E.
        HU-308: A specific agonist for CB(2), a peripheral cannabinoid receptor.
        Proc Natl Acad Sci U S A. 1999; 96: 14228-14233
        • Hunig T.
        • Wallny H.J.
        • Hartley J.K.
        • Lawetzky A.
        • Tiefenthaler G.
        A monoclonal antibody to a constant determinant of the rat T cell antigen receptor that induces T cell activation: Differential reactivity with subsets of immature and mature T lymphocytes.
        J Exp Med. 1989; 169: 73-86
        • Ibrahim M.M.
        • Porreca F.
        • Lai J.
        • Albrecht P.J.
        • Rice F.L.
        • Khodorova A.
        • Davar G.
        • Makriyannis A.
        • Vanderah T.W.
        • Mata H.P.
        • Malan Jr., T.P.
        CB2 cannabinoid receptor activation produces antinociception by stimulating peripheral release of endogenous opioids.
        Proc Natl Acad Sci U S A. 2005; 102: 3093-3098
        • Jubb R.W.
        • Tukmachi E.S.
        • Jones P.W.
        • Dempsey E.
        • Waterhouse L.
        • Brailsford S.
        A blinded randomised trial of acupuncture (manual and electroacupuncture) compared with a non-penetrating sham for the symptoms of osteoarthritis of the knee.
        Acupunct Med. 2008; 26: 69-78
        • Ko J.
        • Na D.S.
        • Lee Y.H.
        • Shin S.Y.
        • Kim J.H.
        • Hwang B.G.
        • Min B.I.
        • Park D.S.
        cDNA microarray analysis of the differential gene expression in the neuropathic pain and electroacupuncture treatment models.
        J Biochem Mol Biol. 2002; 35: 420-427
        • Kong J.
        • Fufa D.T.
        • Gerber A.J.
        • Rosman I.S.
        • Vangel M.G.
        • Gracely R.H.
        • Gollub R.L.
        Psychophysical outcomes from a randomized pilot study of manual, electro, and sham acupuncture treatment on experimentally induced thermal pain.
        J Pain. 2005; 6: 55-64
        • Lane E.B.
        • Rugg E.L.
        • Navsaria H.
        • Leigh I.M.
        • Heagerty A.H.
        • Ishida-Yamamoto A.
        • Eady R.A.
        A mutation in the conserved helix termination peptide of keratin 5 in hereditary skin blistering.
        Nature. 1992; 356: 244-246
        • Lowry O.H.
        • Rosebrough N.J.
        • Farr A.L.
        • Randall R.J.
        Protein measurement with the Folin phenol reagent.
        J Biol Chem. 1951; 193: 265-275
        • Malan Jr., T.P.
        • Ibrahim M.M.
        • Vanderah T.W.
        • Makriyannis A.
        • Porreca F.
        Inhibition of pain responses by activation of CB(2) cannabinoid receptors.
        Chem Phys Lipids. 2002; 121: 191-200
        • Matsuda L.A.
        • Lolait S.J.
        • Brownstein M.J.
        • Young A.C.
        • Bonner T.I.
        Structure of a cannabinoid receptor and functional expression of the cloned cDNA.
        Nature. 1990; 346: 561-564
        • McMahon S.B.
        • Bennett D.L.
        • Priestley J.V.
        • Shelton D.L.
        The biological effects of endogenous nerve growth factor on adult sensory neurons revealed by a trkA-IgG fusion molecule.
        Nat Med. 1995; 1: 774-780
        • Mechoulam R.
        • Fride E.
        • Di Marzo V.
        Endocannabinoids. Eur J Pharmacol. 1998; 359: 1-18
        • Merriam F.V.
        • Wang Z.Y.
        • Guerios S.D.
        • Bjorling D.E.
        Cannabinoid receptor 2 is increased in acutely and chronically inflamed bladder of rats.
        Neurosci Lett. 2008; 445: 130-134
        • Munro S.
        • Thomas K.L.
        • Abu-Shaar M.
        Molecular characterization of a peripheral receptor for cannabinoids.
        Nature. 1993; 365: 61-65
        • Oliveira P.G.
        • Brenol C.V.
        • Edelweiss M.I.
        • Brenol J.C.
        • Petronilho F.
        • Roesler R.
        • Dal-Pizzol F.
        • Schwartsmann G.
        • Xavier R.M.
        Effects of an antagonist of the bombesin/gastrin-releasing peptide receptor on complete Freund's adjuvant-induced arthritis in rats.
        Peptides. 2008; 29: 1726-1731
        • Quartilho A.
        • Mata H.P.
        • Ibrahim M.M.
        • Vanderah T.W.
        • Porreca F.
        • Makriyannis A.
        • Malan Jr., T.P.
        Inhibition of inflammatory hyperalgesia by activation of peripheral CB2 cannabinoid receptors.
        Anesthesiology. 2003; 99: 955-960
        • Rice A.S.
        • Farquhar-Smith W.P.
        • Nagy I.
        Endocannabinoids and pain: Spinal and peripheral analgesia in inflammation and neuropathy.
        Prostaglandins Leukot Essent Fatty Acids. 2002; 66: 243-256
        • Safieh-Garabedian B.
        • Poole S.
        • Allchorne A.
        • Winter J.
        • Woolf C.J.
        Contribution of interleukin-1 beta to the inflammation-induced increase in nerve growth factor levels and inflammatory hyperalgesia.
        Br J Pharmacol. 1995; 115: 1265-1275
        • Sekido R.
        • Ishimaru K.
        • Sakita M.
        Differences of electroacupuncture-induced analgesic effect in normal and inflammatory conditions in rats.
        Am J Chin Med. 2003; 31: 955-965
        • Tewari-Singh N.
        • Rana S.
        • Gu M.
        • Pal A.
        • Orlicky D.J.
        • White C.W.
        • Agarwal R.
        Inflammatory biomarkers of sulfur mustard analog 2-chloroethyl ethyl sulfide-induced skin injury in SKH-1 hairless mice.
        Toxicol Sci. 2009; 108: 194-206
        • Tsui P.
        • Leung M.C.
        Comparison of the effectiveness between manual acupuncture and electro-acupuncture on patients with tennis elbow.
        Acupunct Electrother Res. 2002; 27: 107-117
        • Walczak J.S.
        • Pichette V.
        • Leblond F.
        • Desbiens K.
        • Beaulieu P.
        Behavioral, pharmacological and molecular characterization of the saphenous nerve partial ligation: A new model of neuropathic pain.
        Neuroscience. 2005; 132: 1093-1102
        • Wang L.
        • Zhang Y.
        • Dai J.
        • Yang J.
        • Gang S.
        Electroacupuncture (EA) modulates the expression of NMDA receptors in primary sensory neurons in relation to hyperalgesia in rats.
        Brain Res. 2006; 1120: 46-53
        • Whiteside G.T.
        • Gottshall S.L.
        • Boulet J.M.
        • Chaffer S.M.
        • Harrison J.E.
        • Pearson M.S.
        • Turchin P.I.
        • Mark L.
        • Garrison A.E.
        • Valenzano K.J.
        A role for cannabinoid receptors, but not endogenous opioids, in the antinociceptive activity of the CB2-selective agonist, GW405833.
        Eur J Pharmacol. 2005; 528: 65-72
        • Woolf C.J.
        • Allchorne A.
        • Safieh-Garabedian B.
        • Poole S.
        Cytokines, nerve growth factor and inflammatory hyperalgesia: The contribution of tumour necrosis factor alpha.
        Br J Pharmacol. 1997; 121: 417-424
        • Woolf C.J.
        • Safieh-Garabedian B.
        • Ma Q.P.
        • Crilly P.
        • Winter J.
        Nerve growth factor contributes to the generation of inflammatory sensory hypersensitivity.
        Neuroscience. 1994; 62: 327-331
        • Yung K.T.
        Birdcage model for the Chinese meridian system, VI: Meridians as the primary regulatory system.
        Am J Chin Med. 2005; 33: 759-766
        • Zhang R.X.
        • Lao L.
        • Wang L.
        • Liu B.
        • Wang X.
        • Ren K.
        • Berman B.M.
        Involvement of opioid receptors in electroacupuncture-produced anti-hyperalgesia in rats with peripheral inflammation.
        Brain Res. 2004; 1020: 12-17
        • Zimmermann M.
        Ethical guidelines for investigations of experimental pain in conscious animals.
        Pain. 1983; 16: 109-110