@article{3112419,
    title = "Differential Expression of Collagen Type V and XI α-1 in Human Ascending Thoracic Aortic Aneurysms",
    author = "Toumpoulis, I.K. and Oxford, J.T. and Cowan, D.B. and Anagnostopoulos, C.E. and Rokkas, C.K. and Chamogeorgakis, T.P. and Angouras, D.C. and Shemin, R.J. and Navab, M. and Ericsson, M. and Federman, M. and Levitsky, S. and McCully, J.D.",
    journal = "The Annals of Thoracic Surgery",
    year = "2009",
    volume = "88",
    number = "2",
    pages = "506-513",
    issn = "0003-4975, 1552-6259",
    doi = "10.1016/j.athoracsur.2009.04.030",
    keywords = "collagen type 1;  collagen type 11;  collagen type 3;  collagen type 5;  fibrillar collagen;  messenger RNA, article;  ascending aorta;  clinical article;  controlled study;  elective surgery;  electron microscopy;  extracellular matrix;  gene expression;  gene mutation;  histopathology;  human;  human tissue;  immunofluorescence test;  priority journal;  protein blood level;  quantitative analysis;  real time polymerase chain reaction;  reverse transcription polymerase chain reaction;  thoracic aorta aneurysm;  tissue section;  Western blotting, Aortic Aneurysm, Thoracic;  Collagen Type V;  Collagen Type XI;  Disease Progression;  Extracellular Matrix;  Humans;  Immunohistochemistry;  Proteins;  Reverse Transcriptase Polymerase Chain Reaction;  RNA, Messenger",
    abstract = "Background: The molecular mechanisms leading to ascending thoracic aortic aneurysms (ATAAs) remain unknown. We hypothesized that alterations in expression levels of specific fibrillar collagens occur during the aneurysmal process. Methods: Surgical samples from ascending aortas from patients with degenerative ATAAs were subdivided by aneurysm diameter: small, 5 to 6 cm; medium, 6 to 7 cm; and large, greater than 7 cm; and compared with nonaneurysmal aortas (mean diameter, 2.3 cm). Results: Histology, immunofluorescence, and electron microscopy demonstrated greater disorganization of extracellular matrix constituents in ATAAs as compared with control with an increase in collagen α1(XI) within regions of cystic medial degenerative lesions. Real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) showed collagens type V and α1(XI) were significantly and linearly increased in ATAAs as compared with control (p < 0.001). There was no change in the messenger ribonucleic acid (mRNA) expression levels of collagens type I and III. Western blot analysis showed collagens type I and III were significantly decreased and collagens α1(XI) and V were significantly increased and were linearly correlated with the size of the aneurysm (p < 0.001 for both). Conclusions: These results demonstrate that increased collagen α1(XI) and collagen V mRNA and protein levels are linearly correlated with the size of the aneurysm and provide a potential mechanism for the generation and progression of aneurysmal enlargement. © 2009 The Society of Thoracic Surgeons."
}