Molecular profiles of mRNA levels in laser capture microdissected murine hippocampal regions differentially responsive to TMT-induced cell death.
Using a chemical-induced model of dentate granule (DG) cell death, cDNA microarray analysis was used to identify gene profiles from the laser-captured microdissected (LCM) hippocampal DG cell region versus the CA pyramidal cell layer (CA) from 21-day-old male CD1 mice injected with trimethyltin hydroxide (TMT; 3.0 mg/kg, i.p.). At 6 h post-TMT, lectin + microglia displaying a reactive morphology were in contact with active caspase 3+ neurons. By 18 h, amoeboid microglia and signs of phagocytosis, and a mild astrocytic response were present in the DG. There was no evidence of IgG extravasation in the hippocampus, or cell death and glial reactivity in the CA. Atlas 1.2K Clontech array detected 115 genes changed in the hippocampus with TMT and included genes associated with immediate-early responses, calcium homeostasis, cellular signaling, cell cycle, immunomodulation and DNA repair. Early responses localized to LCM DG samples consisted of elevations in inflammatory factors such as tumor necrosis factor-alpha and receptors, as well as MIP1alpha, CD14, CD18, and a decrease in factors associated with calcium buffering. By 18 h, in the DG, changes occurred in transcripts associated with apoptosis, cell adhesion, DNA repair, cell proliferation and growth. In the CA, a differential level of elevation was seen in CD86 antigen, zinc finger protein 38 and DNA damage inducible transcript 3. A significant number of genes was decreased at these early time points in both hippocampal regions.
Lefebvre d'Hellencourt
Christian
C
Neurotoxicology Group, Laboratory of Molecular Toxicology, National Institute of Environmental Health Sciences, National Institutes of Health, Health and Human Services, Research Triangle Park, North Carolina 27709, USA.
Harry
G Jean
GJ
D000818:Animals; D001253:Astrocytes / Q000378:metabolism / Q000473:pathology; D001930:Brain Injuries / Q000139:chemically induced / Q000235:genetics / Q000378:metabolism*; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002452:Cell Count / Q000379:methods; D016923:Cell Death / Q000187:drug effects; D004195:Disease Models, Animal; D005786:Gene Expression Regulation / Q000187:drug effects; D005904:Glial Fibrillary Acidic Protein / Q000235:genetics / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism / Q000473:pathology*; D007150:Immunohistochemistry / Q000379:methods; D007834:Lasers; D037102:Lectins / Q000378:metabolism; D008297:Male; D051379:Mice; D046228:Microarray Analysis / Q000379:methods; D042282:Microdissection / Q000379:methods; D009474:Neurons / Q000378:metabolism* / Q000473:pathology; D010751:Phosphopyruvate Hydratase / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013997:Time Factors; D014298:Trimethyltin Compounds
D005904:Glial Fibrillary Acidic Protein; D037102:Lectins; D012333:RNA, Messenger; D014298:Trimethyltin Compounds; C037718:trimethyltin hydroxide; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases; D010751:Phosphopyruvate Hydratase