title: Identification of valid housekeeping genes and antioxidant enzyme gene expression change in the aging rat liver.
abstract: Valid housekeeping genes (HKG) are a prerequisite for accurate gene quantification. We performed real-time reverse transcription-polymerase chain reaction to investigate the gene expression of five commonly used HKGs (beta-actin, glyceraldehyde-3-phosphate dehydrogenase [GAPDH], ubiquitin C [UBC], hypoxanthine phosphoribosyl-transferase [HPRT], and cyclophilin A [CYPa]) and antioxidant enzymes in the liver of young and old male Fischer rats. A wide variation in HKG expression existed during the aging process, and HPRT was identified as the most stable HKG in rat liver aging. When Cu/Zn-superoxide dismutase gene expression was normalized to HPRT, there was no detectable difference between young and old rats; however, a significant difference was seen when it was normalized to UBC. The variation of UBC caused the misinterpretation of Cu/Zn-superoxide dismutase expression. Catalase expression was significantly decreased, whereas glutathione peroxidase expression was not altered with age. We demonstrated that HPRT was an appropriate HKG, validation of HKGs was vital for accurate quantification, and decreased catalase expression might be involved in the decline of antioxidant defenses during rat liver aging.
authors.affiliation: Department of Otolaryngology, National University Hospital, Singapore.
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.forename: David A
authors.initials: DA
authors.lastname: Rider
authors.forename: Runsheng
authors.initials: R
authors.lastname: Ruan
mesh_terms: D000367:Age Factors; D000375:Aging / Q000235:genetics*; D000818:Animals; D000975:Antioxidants / Q000502:physiology*; D005786:Gene Expression Regulation; D020043:Genes, Essential / Q000235:genetics*; D008099:Liver / Q000201:enzymology*; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344
chemical_list: D000975:Antioxidants