title: Pentoxifylline attenuates the development of hyperalgesia in a rat model of neuropathic pain.
abstract: Pentoxifylline, a non-specific cytokine inhibitor, has shown to be beneficial in inflammatory pain in both experimental and clinical studies. The present study demonstrates for the first time, to our knowledge, the antihyperalgesic effect of pentoxifylline in the neuropathic pain using L5 spinal nerve transection rat model. In a preventive paradigm, pentoxifylline (12.5, 25, 50, or 100mg/kg intraperitoneally) was administered systemically daily, beginning 1h prior to nerve transection. Pentoxifylline (50, or 100mg/kgi.p.) produced significant decrease in the mechanical and thermal hyperalgesia. However, pentoxifylline (100mg/kgi.p.) did not influence the paw pressure thresholds and paw withdrawal latency in sham-operated rats. In order to understand the possible antinocicieptive effect of pentoxifylline in neuropathic pain, we examined the level of TNFalpha, IL-1beta, IL-6 and IL-10 protein in the contralateral brain on day 7 post-transection. Pentoxifylline administration resulted in a dose-dependent reduction of the production of proinflammatory cytokines like TNFalpha, IL-1beta and IL-6, and enhancement of IL-10. Furthermore, we investigated the activity of nuclear factor kappa B (NF-kappaB) in the contralateral brain on days 7 after surgery. In accordance with the change of proinflammatory cytokines, Pentoxifylline (50 or 100mg/kg) significantly inhibited the activation of NF-kappaB in the brain. This research supports a growing body of literature emphasizing the importance of neuroinflammation and neuroimmune activation in the development of neuropathic pain states, and the potential preventive value of pentoxifylline in the treatment of neuropathic pain.
authors.affiliation: Department of Anaesthesiology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, PR China.
authors.forename: Jian
authors.initials: J
authors.lastname: Liu
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Feng
authors.forename: Min
authors.initials: M
authors.lastname: Yu
authors.forename: Weiying
authors.initials: W
authors.lastname: Xie
authors.forename: Xin
authors.initials: X
authors.lastname: Zhao
authors.forename: Weiyan
authors.initials: W
authors.lastname: Li
authors.forename: Ren
authors.initials: R
authors.lastname: Guan
authors.forename: Jianguo
authors.initials: J
authors.lastname: Xu
mesh_terms: D000818:Animals; D016207:Cytokines / Q000378:metabolism; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D006358:Hot Temperature; D006930:Hyperalgesia / Q000188:drug therapy* / Q000209:etiology*; D008297:Male; D009437:Neuralgia / Q000150:complications*; D010147:Pain Measurement; D017288:Pain Threshold / Q000187:drug effects; D010431:Pentoxifylline / Q000627:therapeutic use*; D010726:Phosphodiesterase Inhibitors / Q000627:therapeutic use*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D000097782:NF-kappaB-Inducing Kinase
chemical_list: D016207:Cytokines; D010431:Pentoxifylline; D010726:Phosphodiesterase Inhibitors; D017346:Protein Serine-Threonine Kinases; D000097782:NF-kappaB-Inducing Kinase