MIN  Youjiang, CHENG Lihong, MIN Zhiyun, PEI Jia

(1  Affiliated Hospital of Jiangxi University of Traditional Chinese Medicine, Nanchang, Jiangxi Province, 330006)

Abstract:  Electroacupuncture  is  beneficial  for  the  recovery  of  spinal  cord  injury,  but  the underlying mechanism  is  unclear.  The  Rho/Rho-associated  kinase  (ROCK)  signaling  pathway regulates the actin cytoskeleton by controlling the adhesive and migratory behaviors of cells that could  inhibit neurite regrowth after neural injury and consequently hinder the recovery from spinal cord injury. Therefore, we hypothesized electroacupuncture could affect the Rho/ROCK signaling pathway to promote the recovery of spinal cord injury. In our experiments, the spinal cord injury in  adult  Sprague-Dawley  rats  was  caused  by  an  impact  device.  Those  rats  were  subjected  to electroacupuncture at Yaoyangguan (GV3), Dazhui (GV14), Zusanli (ST36) and Ciliao (BL32) and/or  monosialoganglioside  treatment.  Behavioral  scores  revealed  that  the  hindlimb  motor functions  improved  with  those  treatments.  Real-time  quantitative  polymerase  chain  reaction, fluorescence  in  situ  hybridization  and  western  blot  assay  showed  that  electroacupuncture suppressed the mRNA and protein expression of Rho-A and Rho-associated kinase II (ROCKII) of injured spinal cord. Although monosialoganglioside promoted the recovery of hindlimb motor function, monosialoganglioside did not affect the expression of Rho-A and ROCKII. However, electroacupuncture  combined  with  monosialoganglioside  did  not  further  improve  the  motor function  or  suppress  the  expression  of  Rho-A  and  ROCKII.  Our  data  suggested  that  the electroacupuncture could specifically inhibit the activation of the Rho/ROCK signaling pathwaythus  partially  contributing  to  the  repair  of  injured  spinal  cord.  Monosialoganglioside  could promote the motor function but did not suppress expression of RhoA and ROCKII. There was no synergistic effect of electroacupuncture combined with monosialoganglioside.

Key  Words:  nerve  regeneration;  spinal  cord  injury;  electroacupuncture;  Rho/Rho-associated kinase  signaling  pathway;  monosialoganglioside;  motor  function;  cytoskeleton;  real-time quantitative  polymerase  chain  reaction;  western  blot  assay;  hybridization  in  situ;  neural regeneration