title: Telomere Length in Peripheral Blood Mononuclear Cells of Patients on Chronic Hemodialysis Is Related With Telomerase Activity and Treatment Duration.
abstract: Telomere shortening to a critical limit is associated with replicative senescence. This process is prevented by the enzyme telomerase. Oxidative stress and chronic inflammation are factors accelerating telomere loss. Chronic hemodialysis, typically accompanied by oxidative stress and inflammation, may be also associated with replicative senescence. To test this hypothesis, we determined telomere length and telomerase activity in peripheral blood mononuclear cells (PBMCs) in a cross-sectional study. Hemodialysis patients at the University Hospital Larissa and healthy controls were studied. Telomere length was determined by the TeloTAGGG Telomere Length Assay and telomerase activity by Telomerase PCR-ELISA (Roche Diagnostics GmbH, Mannheim, Germany). We enrolled 43 hemodialysis patients (17 females; age 65.0 ± 12.7 years) and 23 controls (six females; age 62.1 ± 15.7 years). Between the two groups, there was no difference in telomere length (6.95 ± 3.25 vs. 7.31 ± 1.96 kb; P = 0.244) or in telomerase activity (1.82 ± 2.91 vs. 2.71 ± 3.0; P = 0.085). Telomere length correlated inversely with vintage of hemodialysis (r = -0.332, P = 0.030). In hemodialysis patients, positive telomerase activity correlated with telomere length (r = 0.443, P = 0.030). Only age, and neither telomere length nor telomerase activity, was an independent survival predictor (hazard ratio 1.116, 95% confidence interval 1.009-1.234, P = 0.033). In this study, telomere length and telomerase activity in PBMCs are not altered in hemodialysis patients compared with healthy controls. Long duration of hemodialysis treatment is associated with telomere shortening and positive telomerase activity with an increased telomere length in PBMCs of hemodialysis patients. The underlying mechanism and clinical implications of our findings require further investigation.
authors.affiliation: Clinic of Nephrology, University of Thessaly, Larissa, Greece.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Stefanidis
authors.affiliation: Clinic of Nephrology, University of Thessaly, Larissa, Greece.
authors.forename: Georgios
authors.initials: G
authors.lastname: Voliotis
authors.affiliation: Laboratory of Cytogenetics and Molecular Genetics, University of Thessaly, Larissa, Greece.|Laboratory of Medical Genetics, Center of Research and Technology Thessaly, Larissa, Greece.
authors.forename: Vassilios
authors.initials: V
authors.lastname: Papanikolaou
authors.affiliation: Clinic of Nephrology, University of Thessaly, Larissa, Greece.
authors.forename: Ioanna
authors.initials: I
authors.lastname: Chronopoulou
authors.affiliation: Clinic of Nephrology, University of Thessaly, Larissa, Greece.
authors.forename: Theodoros
authors.initials: T
authors.lastname: Eleftheriadis
authors.affiliation: Centre for Integrated Systems Biology of Ageing and Nutrition, Institute for Ageing and Health, Newcastle University, Newcastle, UK.
authors.forename: Axel
authors.initials: A
authors.lastname: Kowald
authors.affiliation: Laboratory of Biometry and Biomathematics, Faculty of Medicine, University of Thessaly, Larissa, Greece.|Institute for Clinical Research and Health Policy Studies, Tufts University School of Medicine, Boston, MA, USA.
authors.forename: Elias
authors.initials: E
authors.lastname: Zintzaras
authors.affiliation: Laboratory of Cytogenetics and Molecular Genetics, University of Thessaly, Larissa, Greece.|Laboratory of Medical Genetics, Center of Research and Technology Thessaly, Larissa, Greece.
authors.forename: Aspasia
authors.initials: A
authors.lastname: Tsezou
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000628:therapy*; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress; D006435:Renal Dialysis; D019098:Telomerase / Q000378:metabolism*; D016615:Telomere / Q000737:chemistry / Q000378:metabolism*; D059506:Telomere Shortening; D013997:Time Factors
chemical_list: D019098:Telomerase
keywords: End-stage renal disease; Hemodialysis; Peripheral blood mononuclear cells; Telomerase; Telomeres