title: Antinociceptive effects of eugenol evaluated in a monoiodoacetate-induced osteoarthritis rat model.
abstract: The aim of the present study was to evaluate whether eugenol, the main constituent of clove oil, has the capacity to provide analgesia in the monoiodoacetate-induced rat model of osteoarthritis. Animals (n = 6/group) received either eugenol (20 or 40 mg/kg) or a vehicle by gavage. Daily administrations were initiated 2 days post osteoarthritis induction and continued for the duration of the study (4 weeks). Gait analysis was performed using the CatWalk method and secondary mechanical allodynia was assessed with von Frey filaments. Selected spinal cord peptides (substance P, calcitonin gene-related peptide and dynorphin) were quantified by mass spectrometry. Significant changes were identified in dynamic gait parameters (swing speed, swing phase duration and duty cycle) of the affected limb following 40 mg/kg eugenol treatment compared with the vehicle (p < 0.05). Von Frey results revealed significant differences between the 40 mg/kg treatment and the vehicle group during the first and the third week of the study (p < 0.02). Spinal pain-related peptide analysis revealed a decreased content of substance P and CGRP accompanied by an increase of dynorphin in animals treated with 40 mg/kg eugenol. These results suggest a therapeutic potential of eugenol to alleviate osteoarthritis-related pain.
authors.affiliation: Département de Biomédecine Vétérinaire, Faculté de Médecine Vétérinaire, Université de Montréal, 3200 Rue Sicotte, Saint-Hyacinthe, Québec J2S 2 M2, Canada.
authors.forename: Catherine E
authors.initials: CE
authors.lastname: Ferland
authors.forename: Francis
authors.initials: F
authors.lastname: Beaudry
authors.forename: Pascal
authors.initials: P
authors.lastname: Vachon
mesh_terms: D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000032:analysis; D045783:Clove Oil / Q000494:pharmacology; D004195:Disease Models, Animal; D004399:Dynorphins / Q000032:analysis; D005054:Eugenol / Q000494:pharmacology*; D005684:Gait; D006930:Hyperalgesia; D019807:Iodoacetic Acid; D007719:Knee Joint / Q000473:pathology; D008297:Male; D010003:Osteoarthritis / Q000139:chemically induced / Q000188:drug therapy*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000187:drug effects; D013373:Substance P / Q000032:analysis
chemical_list: D000700:Analgesics; D045783:Clove Oil; D013373:Substance P; D005054:Eugenol; D004399:Dynorphins; D015740:Calcitonin Gene-Related Peptide; D019807:Iodoacetic Acid