title: Telomerase expression on aortic wall endothelial cells is attenuated in abdominal aortic aneurysms compared to healthy nonaneurysmal aortas.
abstract: OBJECTIVE
  Linear chromosomes carry specific DNA structures at their ends called telomeres. The latter shorten with each successive cell division making their length a marker of cell age. Telomerase prevents such telomere attrition by adding back telomeric repeats at the telomere ends, thus playing an important role in cell aging. On the other hand, an abdominal aortic aneurysm (AAA) represents an age-related degenerative disorder. The aim of the present study was to investigate a potential correlation of telomerase expression with AAA formation.
  
  
  METHODS
  Aortic wall tissue samples were collected from 49 patients (mean age, 63.8 ± 4.4 years) with AAAs during open elective repair and from 24 deceased organ donors as controls (mean age, 60.5 ± 3.9 years). Telomerase expression on endothelial cells was detected by immunohistochemistry. Associations of telomerase positivity with AAAs and epidemiologic and clinical variables were investigated.
  
  
  RESULTS
  Telomerase expression was significantly decreased in patients with AAAs (11 of 49; 22.4%) compared to controls (19 of 24; 79.2%; P < .001). This association persisted after adjustment for age, gender, coronary artery disease (CAD), hypercholesterolemia, hypertension and smoking (odds ratio, 0.47; 95% confidence interval, 0.14-0.58; P < .01.).
  
  
  CONCLUSIONS
  Patients with AAAs have attenuated telomerase endothelial expression compared to controls, implying a protective role of telomerase against AAA formation. Further investigation of pathways involved in vascular aging may contribute to elucidation of AAA pathogenetic mechanisms.
authors.affiliation: Athens University Medical School, 2nd Surgical Department, Vascular Division, Laikon University General Hospital, Athens, Greece.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Dimitroulis
authors.forename: Athanasios
authors.initials: A
authors.lastname: Katsargyris
authors.forename: Chris
authors.initials: C
authors.lastname: Klonaris
authors.forename: Efthymios D
authors.initials: ED
authors.lastname: Avgerinos
authors.forename: Matrona
authors.initials: M
authors.lastname: Fragou-Plemenou
authors.forename: Gregory
authors.initials: G
authors.lastname: Kouraklis
authors.forename: Christos D
authors.initials: CD
authors.lastname: Liapis
mesh_terms: D000367:Age Factors; D000368:Aged; D017544:Aortic Aneurysm, Abdominal / Q000201:enzymology* / Q000209:etiology / Q000473:pathology; D016022:Case-Control Studies; D016922:Cellular Senescence; D042783:Endothelial Cells / Q000201:enzymology* / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D019098:Telomerase / Q000378:metabolism*
chemical_list: D019098:Telomerase