title: The composition of collagen in the aneurysm wall of men and women.
abstract: Loss of vessel wall integrity by degradation is essential for the development of abdominal aortic aneurysm (AAA) and ultimately its rupture. The observed greater rupture rate in women with AAA might be related to gender differences in the biomechanical properties of the aneurysm wall. The aim of the study was to compare the biomechanically important structure of collagen between men and women with AAA.
  
  
  
  Biopsies of the aneurysm walls were obtained during elective open repair of men (n = 14) and women (n = 14) treated for AAA. High-performance liquid chromatography (HPLC), Western blot, messenger RNA expression, and histochemical analyses were performed to assess the cross-linking and the amount and the composition of collagen.
  
  
  
  There was neither a difference in the thickness of the aneurysm wall, nor in the histological evaluation of the collagen composition between the sexes. Relative collagen content in the aneurysm wall was similar in men and women, as assessed by messenger RNA expression and HPLC. Collagen cross-linking differed between the sexes; women had more lysyl pyridinoline (LP) than men (0.140 vs 0.07; P = .005), resulting in a lower hydroxyl pyridinoline (HP):LP ratio (3.28 vs 8.41; P = .003). There was no difference in messenger RNA and protein expressions of lysyl hydroxylase and lysyl oxidase to associate with the lower HP:LP ratio in women.
  
  
  
  The composition of collagen in the aneurysm wall of men and women are in several aspects similar, with the exception of collagen cross-linking, suggesting that the difference in rupture rate between the sexes rather depend on the composition of other vessel wall structures.
authors.affiliation: Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden; Department of Vascular Surgery, Karolinska University Hospital, Stockholm, Sweden. Electronic address: christina.villard@ki.se.
authors.forename: Christina
authors.initials: C
authors.lastname: Villard
authors.affiliation: Atherosclerosis Research Unit, Center for Molecular Medicine, Department of Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Per
authors.initials: P
authors.lastname: Eriksson
authors.affiliation: TNO Metabolic Health Research, Leiden, The Netherlands.
authors.forename: Roeland
authors.initials: R
authors.lastname: Hanemaaijer
authors.affiliation: Department of Vascular Surgery, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Jan H
authors.initials: JH
authors.lastname: Lindeman
authors.affiliation: Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden; Department of Vascular Surgery, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Rebecka
authors.initials: R
authors.lastname: Hultgren
mesh_terms: D001012:Aorta, Abdominal / Q000737:chemistry* / Q000473:pathology; D017544:Aortic Aneurysm, Abdominal / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D001019:Aortic Rupture / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D001696:Biomechanical Phenomena; D001706:Biopsy; D015153:Blotting, Western; D002851:Chromatography, High Pressure Liquid; D003094:Collagen / Q000032:analysis* / Q000235:genetics; D005260:Female; D054624:Health Status Disparities; D006801:Humans; D008297:Male; D008240:Procollagen-Lysine, 2-Oxoglutarate 5-Dioxygenase / Q000032:analysis / Q000235:genetics; D008249:Protein-Lysine 6-Oxidase / Q000032:analysis / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012737:Sex Factors
chemical_list: D012333:RNA, Messenger; D003094:Collagen; D008240:Procollagen-Lysine, 2-Oxoglutarate 5-Dioxygenase; D008249:Protein-Lysine 6-Oxidase