title: Identification of reference genes for quantitative RT-PCR in ascending aortic aneurysms.
abstract: Hypertension and congenital aortic valve malformations are frequent causes of ascending aortic aneurysms. The molecular mechanisms of aneurysm formation under these circumstances are not well understood. Reference genes for gene activity studies in aortic tissue that are not influenced by aortic valve morphology and its hemodynamic consequences, aortic dilatation, hypertension, or antihypertensive medication are not available so far. This study determines genes in ascending aortic tissue that are independent of these parameters. Tissue specimens from dilated and undilated ascending aortas were obtained from 60 patients (age ≤70 years) with different morphologies of the aortic valve (tricuspid undilated n = 24, dilated n = 11; bicuspid undilated n = 6, dilated n = 15; unicuspid dilated n = 4). Of the studied individuals, 36 had hypertension, and 31 received ACE inhibitors or AT1 receptor antagonists. The specimens were obtained intraoperatively from the wall of the ascending aorta. We analyzed the expression levels of 32 candidate reference genes by quantitative RT-PCR (RT-qPCR). Differential expression levels were assessed by parametric statistics. The expression analysis of these 32 genes by RT-qPCR showed that EIF2B1, ELF1, and PPIA remained constant in their expression levels in the different specimen groups, thus being insensitive to aortic valve morphology, aortic dilatation, hypertension, and medication with ACE inhibitors or AT1 receptor antagonists. Unlike many other commonly used reference genes, the genes EIF2B1, ELF1, and PPIA are neither confounded by aortic comorbidities nor by antihypertensive medication and therefore are most suitable for gene expression analysis of ascending aortic tissue.
authors: Department of Thoracic and Cardiovascular Surgery, Saarland University Hospital, Homburg/Saar, Germany. s9dohenn@stud.uni-saarland.de
authors: Dominic
authors: D
authors: Henn
authors: Doris
authors: D
authors: Bandner-Risch
authors: Hilja
authors: H
authors: Perttunen
authors: Wolfram
authors: W
authors: Schmied
authors: Carlos
authors: C
authors: Porras
authors: Francisco
authors: F
authors: Ceballos
authors: Noela
authors: N
authors: Rodriguez-Losada
authors: Hans-Joachim
authors: HJ
authors: Schäfers
mesh_terms: D000328:Adult; D001011:Aorta / Q000378:metabolism / Q000503:physiopathology; D001014:Aortic Aneurysm / Q000150:complications / Q000235:genetics / Q000503:physiopathology / Q000601:surgery; D021984:Cyclophilin A / Q000235:genetics; D004108:Dilatation, Pathologic / Q000150:complications / Q000378:metabolism / Q000601:surgery; D020717:Eukaryotic Initiation Factor-2B / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000235:genetics / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D044140:Receptor, Angiotensin, Type 1 / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: C512897:ELF1 protein, human; D020717:Eukaryotic Initiation Factor-2B; D009687:Nuclear Proteins; D044140:Receptor, Angiotensin, Type 1; D014157:Transcription Factors; D021984:Cyclophilin A