title: Long-Term Anti-Allodynic Effect of Immediate Pulsed Radiofrequency Modulation through Down-Regulation of Insulin-Like Growth Factor 2 in a Neuropathic Pain Model.
abstract: Pulsed radiofrequency (PRF) is effective in the treatment of neuropathic pain in clinical practice. Its application to sites proximal to nerve injury can inhibit the activity of extra-cellular signal-regulated kinase (ERK) for up to 28 days. The spared nerve injury (SNI)+ immPRF group (immediate exposure to PRF for 6 min after SNI) exhibited a greater anti-allodynic effect compared with the control group (SNI alone) or the SNI + postPRF group (application of PRF for 6 min on the 14th day after SNI). Insulin-like growth factor 2 (IGF2) was selected using microarray assays and according to web-based gene ontology annotations in the SNI + immPRF group. An increase in IGF2 and activation of ERK1/2 were attenuated by the immPRF treatment compared with an SNI control group. Using immunofluorescent staining, we detected co-localized phosphorylated ERK1/2 and IGF2 in the dorsal horn regions of rats from the SNI group, where the IGF2 protein predominantly arose in CD11b- or NeuN-positive cells, whereas IGF2 immunoreactivity was not detected in the SNI + immPRF group. Taken together, these results suggest that PRF treatment immediately after nerve injury significantly inhibited the development of neuropathic pain with a lasting effect, most likely through IGF2 down-regulation and the inhibition of ERK1/2 activity primarily in microglial cells.
authors.affiliation: Department of Chemistry, Fu-Jen Catholic University and Graduate Institute of Basic Medicine, Fu-Jen Catholic University, New Taipei City 24205, Taiwan. anes2yeh@gmail.com.|Department of Anesthesiology and Integrated Pain Management Center, Tri-Service General Hospital and National Defense Medical Center, Taipei 11490, Taiwan. anes2yeh@gmail.com.|School of Medicine, Fu Jen Catholic University, New Taipei City 24205, Taiwan. anes2yeh@gmail.com.
authors.forename: Chun-Chang
authors.initials: CC
authors.lastname: Yeh
authors.affiliation: School of Medicine, Fu Jen Catholic University, New Taipei City 24205, Taiwan. hlsun@cgh.org.tw.|Department of Anesthesiology, Sijhih Cathay General Hospital, New Taipei City 22174, Taiwan. hlsun@cgh.org.tw.
authors.forename: Hsiao-Lun
authors.initials: HL
authors.lastname: Sun
authors.affiliation: Department of Medical Research, Cathay General Hospital, Taipei 10631, Taiwan. science.man2@gmail.com.|Department of Biochemistry, National Defense Medical Center, Taipei 11490, Taiwan. science.man2@gmail.com.
authors.forename: Chi-Jung
authors.initials: CJ
authors.lastname: Huang
authors.affiliation: Department of Anesthesiology and Integrated Pain Management Center, Tri-Service General Hospital and National Defense Medical Center, Taipei 11490, Taiwan. w82556@gmail.com.|Department of Anesthesiology, Cathay General Hospital, Taipei 10631, Taiwan. w82556@gmail.com.
authors.forename: Chih-Shung
authors.initials: CS
authors.lastname: Wong
authors.affiliation: Department of Anesthesiology and Integrated Pain Management Center, Tri-Service General Hospital and National Defense Medical Center, Taipei 11490, Taiwan. cherng1018@yahoo.com.tw.
authors.forename: Chen-Hwan
authors.initials: CH
authors.lastname: Cherng
authors.affiliation: Department of Pain Medicine, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA. BKHuh@mdanderson.org.
authors.forename: Billy Keon
authors.initials: BK
authors.lastname: Huh
authors.affiliation: School of Medicine, Fu Jen Catholic University, New Taipei City 24205, Taiwan. 034407@mail.fju.edu.tw.
authors.forename: Jinn-Shyan
authors.initials: JS
authors.lastname: Wang
authors.affiliation: School of Medicine, Fu Jen Catholic University, New Taipei City 24205, Taiwan. chienccmd@gmail.com.|Department of Medical Research, Cathay General Hospital, Taipei 10631, Taiwan. chienccmd@gmail.com.|Department of Anesthesiology, Cathay General Hospital, Taipei 10631, Taiwan. chienccmd@gmail.com.
authors.forename: Chih-Cheng
authors.initials: CC
authors.lastname: Chien
mesh_terms: D000818:Animals; D016000:Cluster Analysis; D019295:Computational Biology / Q000379:methods; D004195:Disease Models, Animal; D015536:Down-Regulation; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006930:Hyperalgesia / Q000235:genetics* / Q000378:metabolism / Q000628:therapy*; D007335:Insulin-Like Growth Factor II / Q000235:genetics* / Q000378:metabolism; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D058977:Molecular Sequence Annotation; D009437:Neuralgia / Q000235:genetics* / Q000378:metabolism / Q000628:therapy*; D010147:Pain Measurement; D010766:Phosphorylation; D061208:Pulsed Radiofrequency Treatment; D051381:Rats; D015203:Reproducibility of Results; D015398:Signal Transduction
chemical_list: D007335:Insulin-Like Growth Factor II; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3
keywords: Insulin-like growth factor II; extra-cellular signal-regulated kinase 1/2; gene ontology annotations; pulsed radiofrequency; spared nerve injury