Quantifying mRNA in postmortem human brain: influence of gender, age at death, postmortem interval, brain pH, agonal state and inter-lobe mRNA variance.
Author(s): Preece P, Cairns NJ
Publication: Brain Res Mol Brain Res, 2003, Vol. 118, Page 60
PubMed ID: 14559355 PubMed Review Paper? No
Purpose of Paper
Conclusion of Paper
Studies
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Study Purpose
The purpose of this study was to examine the influence and interaction of patient age, gender, diagnosis, and agonal state, brain pH, interlobe variance, and postmortem interval (PMI) on mRNA levels in control and Alzheimer's disease postmortem brain tissue. The genes examined include beta-actin, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), cyclophilin, microtubule-associated protein (MAP) 2, neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP), and amyloid precursor protein (APP) isoform 770.
Summary of Findings:
While the quantity of total RNA extracted per sample was independent of all analyzed variables, the abundance of mRNA as determined by real time qRT-PCR of five genes was consistently and significantly lower in females compared to males. The abundance of the beta-actin transcript was negatively correlated to age at death in control (normal) specimens, and similar patterns were observed with other genes analyzed. Although significant gender-dependent effects were observed in Alzheimer's disease specimens, control specimens showed no clear correlation between PMI and targeted mRNA levels. Brain pH was (1) positively correlated to PMI in Alzheimer's disease specimens but not controls, (2) inconsistently influenced by diagnosis and agonal state, with a lower brain pH observed after a prolonged death, and (3) positively correlated to expression of 4 of the 5 genes for all specimens examined.
Biospecimens
Preservative Types
- Frozen
Diagnoses:
- Alzheimer's Disease
- Autopsy
- Not specified
Platform:
Analyte Technology Platform RNA Electrophoresis RNA Real-time qRT-PCR Pre-analytical Factors:
Classification Pre-analytical Factor Value(s) Preaquisition Patient age 41 - 91 years
Preaquisition Patient gender Female
Male
Preaquisition Diagnosis/ patient condition Alzheimer's disease
No diagnosis of Alzhemier's disease
Biospecimen Aliquots and Components pH Brain pH 5.8 - 7.2
Preaquisition Postmortem interval 4 - 117 h
Preaquisition Cause of death Cardiovascular disease
Bronchopneumonia
Other
Biospecimen Acquisition Biospecimen location Frontal lobe
Temporal lobe
Parietal lobe
Occipital lobe
Real-time qRT-PCR Specific Targeted nucleic acid beta-actin
GAPDH
Cyclophilin
MAP 2
NSE
GFAP
APP 770