Comprehensive Application of Time-of-flight Secondary Ion Mass Spectrometry (TOF-SIMS) for Ionic Imaging and Bio-energetic Analysis of Club Drug-induced Cognitive Deficiency

Sci Rep. 2015 Dec 17:5:18420. doi: 10.1038/srep18420.

Abstract

Excessive exposure to club drug (GHB) would cause cognitive dysfunction in which impaired hippocampal Ca(2+)-mediated neuroplasticity may correlate with this deficiency. However, the potential changes of in vivo Ca(2+) together with molecular machinery engaged in GHB-induced cognitive dysfunction has never been reported. This study aims to determine these changes in bio-energetic level through ionic imaging, spectrometric, biochemical, morphological, as well as behavioral approaches. Adolescent rats subjected to GHB were processed for TOF-SIMS, immunohistochemistry, biochemical assay, together with Morris water maze to detect the ionic, molecular, neurochemical, and behavioral changes of GHB-induced cognitive dysfunction, respectively. Extent of oxidative stress and bio-energetics were assessed by levels of lipid peroxidation, Na(+)/K(+) ATPase, cytochrome oxidase, and [(14)C]-2-deoxyglucose activity. Results indicated that in GHB intoxicated rats, decreased Ca(2+) imaging and reduced NMDAR1, nNOS, and p-CREB reactivities were detected in hippocampus. Depressed Ca(2+)-mediated signaling corresponded well with intense oxidative stress, diminished Na(+)/K(+) ATPase, reduced COX, and decreased 2-DG activity, which all contributes to the development of cognitive deficiency. As impaired Ca(2+)-mediated signaling and oxidative stress significantly contribute to GHB-induced cognitive dysfunction, delivering agent(s) that improves hippocampal bio-energetics may thus serve as a promising strategy to counteract the club drug-induced cognitive dysfunction emerging in our society nowadays.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium / metabolism
  • Cognition Disorders / chemically induced
  • Cognition Disorders / metabolism*
  • Cognition Disorders / physiopathology
  • Cyclic AMP Response Element-Binding Protein / metabolism
  • Diagnostic Imaging / methods*
  • Electron Transport Complex IV / metabolism
  • Energy Metabolism*
  • Hippocampus / metabolism
  • Hippocampus / physiopathology
  • Illicit Drugs
  • Immunoblotting
  • Immunohistochemistry
  • Ions / analysis*
  • Lipid Peroxidation
  • Male
  • Maze Learning / physiology
  • Nitric Oxide Synthase Type I / metabolism
  • Rats, Wistar
  • Receptors, N-Methyl-D-Aspartate / metabolism
  • Sodium-Potassium-Exchanging ATPase / metabolism
  • Spectrometry, Mass, Secondary Ion / methods*

Substances

  • Cyclic AMP Response Element-Binding Protein
  • Illicit Drugs
  • Ions
  • NMDA receptor A1
  • Receptors, N-Methyl-D-Aspartate
  • Nitric Oxide Synthase Type I
  • Electron Transport Complex IV
  • Sodium-Potassium-Exchanging ATPase
  • Calcium