title: Anti-inflammatory and antinociceptive properties of the leaves of Eriobotrya japonica.
abstract: OBJECTIVE
  The leaves of Eriobotrya japonica Lindl. have been widely used as a traditional medicine for the treatment of many diseases including coughs and asthma. The present study was designed to validate the anti-inflammatory and antinociceptive properties of the n-BuOH fraction of E. japonica (LEJ) leaves.
  
  
  METHODS
  The anti-inflammatory properties of LEJ were studied using IFN-γ/LPS activated murine peritoneal macrophage model. The antinociceptive effects of LEJ were assessed using experimental models of pain, including thermal nociception methods, such as the tail immersion test and the hotplate test, and chemical nociception induced by intraperitoneal acetic acid and subplantar formalin in mice. To examine the possible connection of the opioid receptor to the antinociceptive activity of LEJ, we performed a combination test with naloxone, a nonselective opioid receptor antagonist.
  
  
  RESULTS
  In the IFN-γ and LPS-activated murine peritoneal macrophage model, LEJ suppressed NO production and iNOS expression via down-regulation of NF-κB activation. It also attenuated the expression of COX-2 and the secretion of pro-inflammatory cytokines like TNF-α and IL-6. Moreover, LEJ also demonstrated strong and dose-dependent antinociceptive activity compared to tramadol and indomethacin in various experimental pain models. In a combination test using naloxone, diminished analgesic activities of LEJ were observed, indicating that the antinociceptive activity of LEJ is connected with the opioid receptor.
  
  
  CONCLUSIONS
  The results indicate that LEJ had potent inhibitory effects on the inflammatory mediators including nitric oxide, iNOS, COX-2, TNF-α and IL-6 via the attenuation of NF-κB translocation to the nucleus. LEJ also showed excellent antinociceptive activity in both central and peripheral mechanism as a weak opioid agonist. Based on these results, LEJ may possibly be used as an anti-inflammatory and an analgesic agent for the treatment of pains and inflammatory diseases.
authors.affiliation: College of Pharmacy, Woosuk University, Chonbuk 565-701, Republic of Korea.
authors.forename: Dong Seok
authors.initials: DS
authors.lastname: Cha
authors.forename: Jae Soon
authors.initials: JS
authors.lastname: Eun
authors.forename: Hoon
authors.initials: H
authors.lastname: Jeon
mesh_terms: D019342:Acetic Acid; D000701:Analgesics, Opioid / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology / Q000627:therapeutic use*; D016861:Cyclooxygenase Inhibitors; D004305:Dose-Response Relationship, Drug; D031983:Eriobotrya; D005260:Female; D005557:Formaldehyde; D006358:Hot Temperature; D007213:Indomethacin / Q000494:pharmacology; D018836:Inflammation Mediators / Q000378:metabolism*; D007371:Interferon-gamma; D008070:Lipopolysaccharides; D017737:Macrophages, Peritoneal / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008813:Mice, Inbred ICR; D009270:Naloxone / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D010146:Pain / Q000139:chemically induced / Q000188:drug therapy*; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use; D018515:Plant Leaves; D011957:Receptors, Opioid / Q000187:drug effects / Q000378:metabolism
chemical_list: D000701:Analgesics, Opioid; D000893:Anti-Inflammatory Agents; D016861:Cyclooxygenase Inhibitors; D018836:Inflammation Mediators; D008070:Lipopolysaccharides; D009292:Narcotic Antagonists; D010936:Plant Extracts; D011957:Receptors, Opioid; D005557:Formaldehyde; D009270:Naloxone; D007371:Interferon-gamma; D019342:Acetic Acid; D007213:Indomethacin