title: Role of the AMPK signaling pathway in early brain injury after subarachnoid hemorrhage in rats.
abstract: BACKGROUND
  AMP-activated protein kinase (AMPK) is a key metabolic and stress sensor/effector. Few investigations have been performed to study the role of AMPK in subarachnoid hemorrhage (SAH)-induced early brain injury (EBI). This study was undertaken to investigate the time course of AMPK activation in the early stage of SAH and to evaluate the influence of AICAR (which is known to mimic AMP and activates AMPK) and compound C (a commonly used AMPK inhibitor) on EBI in rats following SAH.
  
  
  METHODS
  Adult male rats were divided into six groups: control, sham, SAH, SAH + vehicle, SAH + AICAR and SAH + compound C. SAHs were induced by a modified endovascular perforation method. Immunohistochemistry, real-time PCR and Western blot were used to detect the spatial and dynamic expression of AMPK after SAH. Cortical apoptosis and the expressions of apoptosis-related proteins such as FOXO3a (forkhead box, class O, 3a) and Bim (Bcl-2-interacting mediator of cell death) were detected after different drug interventions.
  
  
  RESULTS
  We found SAH induced prolonged activation of AMPK. Treatment with AICAR markedly induced overactivation of AMPK and upregulation of FOXO3a and Bim. AICAR also significantly exacerbated cerebral apoptosis and neurological impairment following SAH. On the other hand, pre-administration of compound C attenuated EBI in this SAH model by modulating cerebral apoptosis by inhibiting FOXO3a and Bim.
  
  
  CONCLUSIONS
  Our findings suggest that the AMPK pathway may play an important role in SAH-induced neuronal apoptosis, and the use of AMPK inhibitors can provide neuroprotection in EBI after SAH.
authors.affiliation: Department of Neurosurgery, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi, P. R. China.
authors.forename: Ji-Yang
authors.initials: JY
authors.lastname: An
authors.forename: Li-Li
authors.initials: LL
authors.lastname: Zhou
authors.forename: Peng
authors.initials: P
authors.lastname: Sun
authors.forename: Hong-Gang
authors.initials: HG
authors.lastname: Pang
authors.forename: Dan-Dong
authors.initials: DD
authors.lastname: Li
authors.forename: Yu
authors.initials: Y
authors.lastname: Li
authors.forename: Ming
authors.initials: M
authors.lastname: Zhang
authors.forename: Jin-Ning
authors.initials: JN
authors.lastname: Song
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000378:metabolism*; D000818:Animals; D017209:Apoptosis; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction; D013345:Subarachnoid Hemorrhage / Q000378:metabolism*
chemical_list: D055372:AMP-Activated Protein Kinases