title: NDRG2 is involved in anti-apoptosis induced by electroacupuncture pretreatment after focal cerebral ischemia in rats.
abstract: OBJECTIVE
  We first reported that electroacupuncture (EA) pretreatment at the Baihui acupoint (GV20) induces ischemic tolerance. Our recent study demonstrated that N-Myc downstream-regulated gene 2 (NDRG2) expression was up-regulated following transient focal cerebral ischemia. Therefore, we investigated whether NDRG2 was involved in the ischemic tolerance induced by EA pretreatment in rats.
  
  
  METHODS
  Twenty-four hours after the end of the last EA pretreatment, focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) for 120 minutes in male Sprague-Dawley rats. The neurobehavioral score, infarction volume, and extent of neuronal apoptosis were evaluated at 24 hours after reperfusion. The expression of NDRG2 in the brain was evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR), western blotting, and immunofluorescent staining.
  
  
  RESULTS
  Electroacupuncture pretreatment decreased infarction volume and improved neurologic scores at 24 hours after reperfusion. Double immunofluorescence revealed that NDRG2 expression in astrocytes was suppressed in the EA group at 24 hours after reperfusion, and that NDRG2 protein expression was weak in the nucleus and strong in the cytoplasm of the EA group, but strong in the nucleus of the MCAO group. Triple immunofluorescent staining for terminal deoxynucleotidyl transferase nick-end labeling (TUNEL), NDRG2, and 4',6-diamidino-2-phenylindole (DAPI) showed that NDRG2 co-localised with apoptotic cells. Moreover, the number of apoptotic cells decreased with the attenuation of NDRG2 expression in the EA group compared to the MCAO group.
  
  
  CONCLUSIONS
  Our results indicated that NDRG2 is involved in anti-apoptosis induced by EA pretreatment after focal cerebral ischemia in rats. N-Myc downstream-regulated gene 2 was involved in EA pretreatment-induced cerebral ischemic tolerance. These findings may be important for our understanding of the cellular signaling pathways induced by EA pretreatment.
authors.affiliation: Department of Anesthesiology, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi Province, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.forename: Zijun
authors.initials: Z
authors.lastname: Gao
authors.forename: Xuying
authors.initials: X
authors.lastname: Li
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Haixing
authors.initials: H
authors.lastname: Zhong
authors.forename: Ning
authors.initials: N
authors.lastname: Xu
authors.forename: Feng
authors.initials: F
authors.lastname: Cao
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wang
authors.forename: Lize
authors.initials: L
authors.lastname: Xiong
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D015153:Blotting, Western; D002545:Brain Ischemia / Q000378:metabolism*; D015536:Down-Regulation; D015671:Electroacupuncture; D005455:Fluorescent Antibody Technique; D020287:In Situ Nick-End Labeling; D008297:Male; D009419:Nerve Tissue Proteins / Q000096:biosynthesis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: C507213:Ndrg2 protein, rat; D009419:Nerve Tissue Proteins