title: Altered brain metabolism after whole body irradiation in mice: a preliminary in vivo 1H MRS study.
abstract: Abstract Purpose: In the classical description of acute radiation syndrome, the role of central nervous system (CNS) is underestimated. It is now well recognised that ionising radiation-induced oxidative stress may bring about functional changes in the brain. In this study, we prospectively evaluated metabolic changes in the brain after whole body irradiation in mice using in vivo proton ((1)H) nuclear magnetic resonance spectroscopy (MRS).
  
  
  METHODS
  Young adult mice were exposed to whole body irradiation of 8 Gy and controls were sham irradiated. In vivo (1)H MRS from cortex-hippocampus and hypothalamic-thalamic region of brain at different time points, i.e., as early as 6 hours, day 1, 2, 3, 5 and 10 post irradiation was carried out at 7 Tesla animal magnetic resonance imaging system. Brain metabolites were measured and quantitative analysis of detectable metabolites was performed by linear combination of model (LCModel).
  
  
  RESULTS
  Significant reduction in myoinositol (p = 0.03) and taurine (p = 0.02) ratios were observed in cortex-hippocampus region as early as day 2 post irradiation compared to controls. These metabolic alterations remained sustained over day 10 post irradiation.
  
  
  CONCLUSIONS
  The results of this preliminary study suggest that the alteration/reduction in the mI and Tau concentration may be associated with physiological perturbations in astrocytes or radiation induced neuro-inflammatory response triggered in microglial cell.
authors.affiliation: NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (INMAS), Delhi.
authors.forename: Poonam
authors.initials: P
authors.lastname: Rana
authors.forename: Ahmad Raza
authors.initials: AR
authors.lastname: Khan
authors.forename: Shilpi
authors.initials: S
authors.lastname: Modi
authors.forename: B S
authors.initials: BS
authors.lastname: Hemanth Kumar
authors.forename: Salim
authors.initials: S
authors.lastname: Javed
authors.forename: Rajendra Prasad
authors.initials: RP
authors.lastname: Tripathi
authors.forename: Subash
authors.initials: S
authors.lastname: Khushu
mesh_terms: D000818:Animals; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001921:Brain / Q000378:metabolism* / Q000528:radiation effects*; D002540:Cerebral Cortex / Q000378:metabolism / Q000528:radiation effects; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism; D005973:Glutamine / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism / Q000528:radiation effects; D007031:Hypothalamus / Q000378:metabolism / Q000528:radiation effects; D007294:Inositol / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D051379:Mice; D008959:Models, Neurological; D018384:Oxidative Stress / Q000528:radiation effects; D010725:Phosphocreatine / Q000378:metabolism; D013654:Taurine / Q000378:metabolism; D013788:Thalamus / Q000378:metabolism / Q000528:radiation effects; D013997:Time Factors; D014018:Tissue Distribution
chemical_list: D010725:Phosphocreatine; D005973:Glutamine; D013654:Taurine; D001224:Aspartic Acid; D018698:Glutamic Acid; D007294:Inositol; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline