Hypoxia Induces autophagic cell death through hypoxia-inducible factor 1α in microglia

PLoS One. 2014 May 12;9(5):e96509. doi: 10.1371/journal.pone.0096509. eCollection 2014.

Abstract

As phagocytic cells of central nervous system, excessive activation or cell death of microglia is involved in a lot of nervous system injury and degenerative disease, such as stroke, epilepsy, Parkinson's disease, Alzheimer's disease. Accumulating evidence indicates that hypoxia upregulates HIF-1α expression leading to cell death of microglia. However, the exact mechanism of cell death induced by hypoxia in microglia is not clear. In the current study, we showed that hypoxia induced cell death and autophagy in microglia. The suppression of autophagy using either pharmacologic inhibitors (3-methyladenine, bafilomycin A1) or RNA interference in essential autophagy genes (BECN1 and ATG5) decreased the cell death induced by hypoxia in microglia cells. Moreover, the suppression of HIF-1α using either pharmacologic inhibitors (3-MA, Baf A1) or RNA interference decreased the microglia death and autophagy in vitro. Taken together, these data indicate that hypoxia contributes to autophagic cell death of microglia through HIF-1α, and provide novel therapeutic interventions for cerebral hypoxic diseases associated with microglia activation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenine / analogs & derivatives
  • Adenine / pharmacology
  • Autophagy / drug effects
  • Autophagy / physiology*
  • Cell Hypoxia / physiology*
  • Cell Line
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / metabolism*
  • Microglia / cytology*
  • Microglia / metabolism*
  • Microscopy, Electron, Transmission

Substances

  • Hypoxia-Inducible Factor 1, alpha Subunit
  • 3-methyladenine
  • Adenine

Grants and funding

This study was supported by a grant from National Natural Science Foundation of China (No. 81200908), National Basic Research Program of China (973Program) (No. 2014CB541600) and Major International (Regional) Joint Research Project of China (No. 81220108009). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.