Autophagy is induced by ischemic preconditioning in human livers formerly treated by chemotherapy to limit necrosis

Autophagy. 2010 Jan;6(1):172-4. doi: 10.4161/auto.6.1.10699. Epub 2010 Jan 18.

Abstract

The effectiveness of ischemic preconditioning (IP) against hepatic ischemia/reperfusion injury during human liver surgery is linked to decreased apoptotic cell death as well as preservation of the ATP content in liver tissue. Overproduction of Bcl-2 is reported in preconditioned organs. In human liver biopsies exhibiting steatosis and/or vascular injuries (mainly peliosis) induced by chemotherapy, we find that the expression of Bcl-2 in centrolobular and peliotic areas colocalizes with the autophagy protein Beclin 1 in IP livers. Increased expression of phosphorylated Bcl-2 in preconditioned livers is associated with decreased immunoprecipitation of Beclin 1 and increased expression of LC3-II. The increased number of autophagic vacuoles seen by electron microscopy confirmed that IP could trigger autophagy in chemotherapy-injured livers, probably to reduce the pro-inflammatory necrotic cell death of hepatocytes or endothelial cells and to increase ATP levels. Indeed, necrosis is less frequent (p = 0.04) in IP livers than in the others although no change in apoptosis as assessed by TUNEL assay or caspase-3, -8 and -9 expressions is observed. In conclusion, Bcl-2 and Beclin 1 could be major targets in the regulation of cell death during ischemia/reperfusion injury modulating autophagy to switch on/off necrosis and/or apoptosis.

Publication types

  • Review

MeSH terms

  • Antineoplastic Combined Chemotherapy Protocols / adverse effects*
  • Apoptosis / physiology
  • Autophagy / physiology*
  • Cell Survival / physiology
  • Humans
  • Ischemic Preconditioning* / methods
  • Liver / blood supply*
  • Liver / drug effects
  • Liver / pathology*
  • Liver / surgery
  • Models, Biological
  • Necrosis / chemically induced
  • Necrosis / pathology
  • Necrosis / prevention & control
  • Preoperative Care / methods
  • Reperfusion Injury / pathology
  • Reperfusion Injury / prevention & control