Table 1.

Identification of differentially regulated genes in young-old and oldest-old subjects, assessed by genome-wide microarray RNA studies

Metabolic pathway	Gene name	Symbol	YO	OO
OXPHOS	Cytochrome c oxidase subunit Vic	COX6C	−6.20	−4.72
Glycolysis	Phosphoglycerate kinase 1	PGK1	−3.35	−6.18
	Glucose phosphate isomerase	GPI	−5.55	−3.27
	Phosphofructokinase, muscle	PFKM	−0.30	−5.42
	Glyceraldehyde-3-phosphate dehydrogenase	GAPDH	−1.96	−4.96
Glucose, lipid, oxidation, mitochondria	Peroxisome proliferative activated receptor, gamma, coactivator 1, alpha	PPARGC1A	−4.85	−0.65
TCA	Citrate synthase	CS	−1.96	−4.96
	ATP citrate lyase	ACLY	−3.20	−2.01
Pyruvate metabolism	Pyruvate dehydrogenase (lipoamide) beta	PDHB	−2.13	−3.03
	Pyruvate dehydrogenase kinase, isozyme 3	PDK3	−0.21	4.43
	Pyruvate dehydrogenase (lipoamide) alpha 1	PDHA1	−2.44	−3.57

Notes: Postmortem specimens from 15 brain regions¹⁹ were analyzed by microarray technology. A comparative analysis tool (GXTM Explorer v.3, Gene Logic, Inc., Gaithersburg, MD, USA) was used to calculate potential changes in individual gene expression across the brains of young-old or oldest-old dementia subjects compared to age-matched normal neurological controls, with respect to fold changes, max t-scores (pair-wise standardized measures of gene expression change for individual transcript across all analyzed regions,³⁹,⁴⁰) and t-test P-values for each transcript. The table presents a list of energy metabolism genes with significantly altered expression across the brains of young-old and/or oldest-old dementia subjects versus normal neurological control subjects (P<0.01). Also presented are max t-scores reflecting the magnitude of change across the brain. Positive and negative t-scores reflect, respectively, up- and downregulation of genes. Maximum t-scores reflect significant gene expression difference (P<0.01) between young-old or oldest-old dementia subjects versus age-matched normal neurological controls.¹⁹,²⁰

Abbreviations: RNA, ribonucleic acid; OXPHOS, oxidative phosphorylation; YO, young-old subjects; OO, oldest-old subjects; TCA, tricarboxylic acid; ATP, adenosine triphosphate.