title: [Cellular memory of high glucose exposure in normoglycemia is probably mediated by reactive oxygen species in INS-1 cells].
abstract: OBJECTIVE
  To investigate the cellular memory of previous high glucose exposure in rat islet cell line (INS-1) and explore the possible mechanism.
  
  
  METHODS
  INS-1 cells were exposed to a high glucose (33.3 mmol/L) culture for 48 h followed by further culture in the presence of 11.1 mmol/L glucose in the culture medium for 3 or 5 days. The levels of bax and caspase-3 mRNA were measured by real-time PCR, the production of reactive oxygen species (ROS) was assayed using the dihydroethidium probe, and the cell viability was detected by MTT assay.
  
  
  RESULTS
  High glucose exposure of the cells for 48 h resulted in significantly increased ROS production and bax and caspase-3 mRNA expressions and lowered cell viability (P<0.001). In cells cultured in 11.1 mmol/L glucose following previous high glucose exposure, the ROS production and bax and caspase-3 mRNA expressions still maintained the high levels (P<0.05) while the cell viability remained significantly lower than the control cells (P<0.001).
  
  
  CONCLUSIONS
  High glucose causes persistent changes in cell viability and apoptosis-related gene expressions even after recovery of normoglycemia, the mechanism of which is probably related to increased ROS production.
authors.affiliation: Department of Endocrinology and Metabolism, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors.forename: Wei-Ping
authors.initials: WP
authors.lastname: Wei
authors.forename: Yao-Ming
authors.initials: YM
authors.lastname: Xue
authors.forename: Fang
authors.initials: F
authors.lastname: Gao
authors.forename: Bo
authors.initials: B
authors.lastname: Zhu
authors.forename: Chen-Zhong
authors.initials: CZ
authors.lastname: Li
mesh_terms: D000818:Animals; D053148:Caspase 3 / Q000378:metabolism; D002460:Cell Line; D005947:Glucose / Q000009:adverse effects* / Q000378:metabolism; D050417:Insulin-Secreting Cells / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism*; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: C494828:Bax protein, rat; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D051028:bcl-2-Associated X Protein; C505410:Casp3 protein, rat; D053148:Caspase 3; D005947:Glucose