title: Tumor necrosis factor-α inhibitors alleviation of experimentally induced neuropathic pain is associated with modulation of TNF receptor expression.
abstract: Inflammation plays a key role in the development of sensitization after peripheral nerve damage. We recently demonstrated that tumor necrosis factor-α receptor (TNFR) levels in the spinal cord correlate with pain sensation in herniated disc patients in a rat chronic constriction injury (CCI) model. By using the sciatic nerve CCI model, we studied the effect of anti-TNF-α treatment on recovery from hypersensitivity and TNFR expression in the dorsal root ganglion (DRG) and dorsal horn (DH). Experimental groups consisted of sham-operated and CCI-operated rats that received two s.c. injections (one immediately after surgery, the other 5 days later), both containing saline, etanercept (3 mg/kg body weight), or infliximab (10 mg/kg body weight). Mechanical allodynia (with von Frey filaments) and thermal hyperalgesia (Hargreaves test) were assessed preoperatively and weekly during the first 4 postoperative weeks. DRG and DH samples were collected 2 and 4 weeks after surgery and analyzed for TNFR1 and TNFR2 protein levels by Western blotting and analyzed for mRNA levels by quantitative real-time polymerase chain reaction. Anti-TNF-α treatment resulted in a significant alleviation of pain. TNFR levels were increased five- to sixfold in CCI rats compared with sham controls. Both treatments significantly diminished these increased levels. Treated animals that showed a ≥50% alleviation of pain exhibited a significantly reduced TNF R1/R2 mRNA ratio compared with treated animals that recovered less well. These results demonstrate that attenuation of TNFR expression is associated with recovery from nerve injury and suggest that this may be one of the working mechanisms of anti-TNF therapies.
authors: Department of Translational Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands; Department of Neurosurgery, Maastricht University Medical Center, Maastricht, The Netherlands; Department of Neurosurgery, University of Cologne, Cologne, Germany.
authors: Pablo
authors: P
authors: Andrade
authors: Govert
authors: G
authors: Hoogland
authors: John S
authors: JS
authors: Del Rosario
authors: Harry W
authors: HW
authors: Steinbusch
authors: Veerle
authors: V
authors: Visser-Vandewalle
authors: Marc A
authors: MA
authors: Daemen
mesh_terms: D000700:Analgesics / Q000627:therapeutic use*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D004195:Disease Models, Animal; D000068800:Etanercept; D005727:Ganglia, Spinal / Q000187:drug effects / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006930:Hyperalgesia / Q000188:drug therapy; D007074:Immunoglobulin G / Q000627:therapeutic use*; D000069285:Infliximab; D008297:Male; D017288:Pain Threshold / Q000187:drug effects; D010812:Physical Stimulation; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011917:Rats, Inbred Lew; D018124:Receptors, Tumor Necrosis Factor / Q000235:genetics / Q000378:metabolism* / Q000627:therapeutic use; D012585:Sciatica / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D066148:Spinal Cord Dorsal Horn / Q000187:drug effects / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D000700:Analgesics; D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G; D012333:RNA, Messenger; D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha; D000069285:Infliximab; D000068800:Etanercept
keywords: TNFR; etanercept; infliximab; neuropathic pain; tumor necrosis factor