title: Effects of Ginkgo Biloba Extract EGb-761 on Neuropathic Pain in Mice: Involvement of Opioid System.
abstract: Neuropathic pain is considered as one of the most difficult types of pain to manage with conventional analgesics. EGb-761 is extracted from leaves of Ginkgo biloba and has analgesia and anti-inflammatory properties. This study aimed to examine the effect of EGb-761 on chronic constriction injury (CCI)-induced neuropathic pain behaviors, including thermal hyperalgesia and mechanical allodynia, and to explore the possible mechanisms underlying this action. To this end, CCI mice were intraperitoneally injected with EGb-761 (10, 20, 40, and 80 mg/kg), and thermal hyperalgesia, mechanical allodynia, cytokines, and mu-opioid receptor expression were measured. Results showed that EGb-761 attenuated thermal hyperalgesia and mechanical allodynia dose-dependently and the best delivery time window was from day 7 to day 14 after CCI. Additionally, EGb-761 treatment significantly decreased pro-inflammatory cytokines and enhanced mu opioid receptor (MOR) expression in the sciatic nerve. Moreover, the opioid antagonist naloxone prevented the effect of EGb-761 on thermal hyperalgesia and mechanical allodynia but did not influence the effect of EGb-761 on inflammatory cytokines. In conclusion, this study suggests that the potential of EGb-761 as a new analgesic for neuropathic pain treatment, and opioid system may be involved in the EGb-761-induced attenuation of thermal hyperalgesia and mechanical allodynia. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Institute of Orthopaedics, Xijing Hospital, The Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, P. R. China.|Department of Orthopaedics, 3rd hospital of PLA, Baoji, 721004, Shaanxi Province, P. R. China.
authors.forename: Chao
authors.initials: C
authors.lastname: Zhu
authors.affiliation: Department of Orthopaedics, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710000, Shaanxi Province, P. R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: The Out-patient Department, 3rd hospital of PLA, Baoji, 721004, Shaanxi Province, P. R. China.
authors.forename: Fan
authors.initials: F
authors.lastname: Xu
authors.affiliation: Institute of Orthopaedics, Xijing Hospital, The Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, P. R. China.
authors.forename: Mo
authors.initials: M
authors.lastname: Li
authors.affiliation: Institute of Orthopaedics, Xijing Hospital, The Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, P. R. China.
authors.forename: Liu
authors.initials: L
authors.lastname: Yang
authors.affiliation: Institute of Orthopaedics, Xijing Hospital, The Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, P. R. China.
authors.forename: Xue-Yu
authors.initials: XY
authors.lastname: Hu
authors.affiliation: Institute of Orthopaedics, Xijing Hospital, The Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, P. R. China. ye5mis@163.com.
authors.forename: Zheng-Xu
authors.initials: ZX
authors.lastname: Ye
authors.affiliation: Institute of Orthopaedics, Xijing Hospital, The Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, P. R. China. surgeonwz@126.com.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Institute of Orthopaedics, Xijing Hospital, The Fourth Military Medical University, Xi'an, 710032, Shaanxi Province, P. R. China. zuojingluo@sina.com.
authors.forename: Zhuo-Jing
authors.initials: ZJ
authors.lastname: Luo
mesh_terms: D000701:Analgesics, Opioid / Q000737:chemistry*; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D004195:Disease Models, Animal; D020441:Ginkgo biloba / Q000737:chemistry*; D008297:Male; D051379:Mice; D009437:Neuralgia / Q000188:drug therapy*; D010936:Plant Extracts / Q000494:pharmacology; D017207:Rats, Sprague-Dawley
chemical_list: D000701:Analgesics, Opioid; D000893:Anti-Inflammatory Agents; D010936:Plant Extracts
keywords: Ginkgo biloba; analgesia; neuropathic pain; opioid receptor