title: Gene expression profile changes in rat dorsal horn after sciatic nerve injury.
abstract: OBJECTIVE
  This study aims to investigate gene expression changes in rat dorsal horns after sciatic nerve injury (SNI).
  
  
  METHODS
  The GSE18803 microarray data collected from young and adult rats were downloaded from GEO. After preprocessing, differentially expressed genes (DEGs) between SNI and sham-operated groups were selected using Limma package, in young and adult group, respectively, followed by Venn analysis. Then, enrichment analyses were performed for these DEGs using DAVID. The STRING database was used to identify protein-protein interactions (PPIs) among these DEGs, and the module network was further extracted using plugin ClusterONE. Finally, protein domain enrichment analysis of DEGs in each module was performed using InterPro database.
  
  
  RESULTS
  Totally, 210 and 50 DEGs were identified in adult and young group, respectively. Among them, 160 were specific in adult group (e.g. CCL2, NF-κB1 and RAC2); 9 were specific in young group (e.g. ILF3 and LYVE1); and 41 were common in both two groups (e.g. FCER1G, C1QA, C1QB and C1QC). The up-regulated DEGs were mostly enriched in immune response-related biological processes, as well as 15 immune- and inflammation-related pathways. Then, two modules were identified in PPI network. CCL2 and NF-κB1 had high connectivity degrees in module 1, and RAC2, FCER1G and CD68 in module 2.
  
  
  CONCLUSIONS
  CCL2, NF-κB1, RAC2, FCER1G and C1Q may contribute to the generation of neuropathic pain after SNI via immune and defense pathways. Among the five genes, the first three are specific in adult population, while the latter two are age-independent. They all might function through involvement of these immune or inflammatory pathways.
authors.affiliation: a Department of Pain Management , Henan Provincial People's Hospital, The People's Hospital of Zhengzhou University , Zhengzhou , China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: a Department of Pain Management , Henan Provincial People's Hospital, The People's Hospital of Zhengzhou University , Zhengzhou , China.
authors.forename: Song-He
authors.initials: SH
authors.lastname: Ma
authors.affiliation: a Department of Pain Management , Henan Provincial People's Hospital, The People's Hospital of Zhengzhou University , Zhengzhou , China.
authors.forename: Rong
authors.initials: R
authors.lastname: Tao
authors.affiliation: a Department of Pain Management , Henan Provincial People's Hospital, The People's Hospital of Zhengzhou University , Zhengzhou , China.
authors.forename: Ling-Jie
authors.initials: LJ
authors.lastname: Xia
authors.affiliation: a Department of Pain Management , Henan Provincial People's Hospital, The People's Hospital of Zhengzhou University , Zhengzhou , China.
authors.forename: Lin
authors.initials: L
authors.lastname: Liu
authors.affiliation: a Department of Pain Management , Henan Provincial People's Hospital, The People's Hospital of Zhengzhou University , Zhengzhou , China.
authors.forename: Ying-Hai
authors.initials: YH
authors.lastname: Jiang
mesh_terms: D000367:Age Factors; D000818:Animals; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000235:genetics*; D053263:Gene Regulatory Networks / Q000235:genetics; D040081:Protein Array Analysis; D051381:Rats; D020426:Sciatic Neuropathy / Q000473:pathology*; D066148:Spinal Cord Dorsal Horn / Q000378:metabolism*
keywords: Sciatic nerve injury; adult; age-independent; differentially expressed genes; enrichment analysis; module analysis; protein–protein interaction