Suppression of Inner Mitochondrial Membrane Peptidase 2-Like (IMMP2L) Gene Exacerbates Hypoxia-Induced Neural Death Under High Glucose Condition

Neurochem Res. 2017 May;42(5):1504-1514. doi: 10.1007/s11064-017-2207-y. Epub 2017 Mar 18.

Abstract

It is known that diabetes hyperglycemia enhances cerebral ischemia and reperfusion induced damage. We have previously shown that mutation of inner mitochondrial membrane peptidase 2-like (IMMP2L) increases brain damage caused by transient cerebral ischemia. In this study, we attempt to examine the impact of IMMP2L deficiency on an in vitro model that mimics the diabetic hypoxic conditions. Normal IMMP2L wild type and IMMP2L gene deleted HT22 cells were cultured. Hypoxia was induced under high glucose and acidic conditions with 4 h of oxygen deprivation. Cell viability was assessed by CCK-8 assay and cell death was determined using Annexin V/7-AAD assay. Superoxide production was measured using dihydroethidium staining and mitochondrial membrane potential was detected using JC-1 probe. Suppression of IMMP2L reduced the cell viability, increased the ROS production and decreased the mitochondrial membrane potential. In conclusion, our study demonstrated that deficiency of IMMP2L in cells, cultured under hypoxia, high glucose and acidic conditions, exacerbated neuronal death under a condition that mimics in vivo cerebral ischemia in diabetic condition.

Keywords: Cerebral ischemia/reperfusion injury; Diabetes; IMMP2L.

MeSH terms

  • Animals
  • Cell Death / drug effects
  • Cell Death / physiology
  • Cell Hypoxia / drug effects
  • Cell Hypoxia / physiology
  • Cell Survival / drug effects
  • Cell Survival / physiology
  • Endopeptidases / deficiency*
  • Endopeptidases / genetics
  • Glucose / administration & dosage
  • Glucose / toxicity*
  • HEK293 Cells
  • Humans
  • Membrane Potential, Mitochondrial / drug effects
  • Membrane Potential, Mitochondrial / physiology
  • Mice
  • Mitochondrial Membranes / drug effects
  • Mitochondrial Membranes / metabolism*
  • Neurons / drug effects
  • Neurons / metabolism*

Substances

  • Endopeptidases
  • IMMP2L protein, human
  • Glucose