title: The activity of antioxidant enzymes in blood platelets in different types of renal replacement therapy: a cross-sectional study.
abstract: OBJECTIVE
  The changes in redox status characterise physiological platelet activation. Increased oxidative stress in chronic kidney disease (CKD) associated with uremic toxicity and procedures of renal replacement therapy leads to the impairment of antioxidant properties of platelets. It may contribute to thrombosis and cardiovascular complications increasing morbidity and mortality among the CKD patients. The object of the research was to assess the influence of conservative treatment, peritoneal dialysis and haemodialysis on platelet prooxidative-antioxidative balance.
  
  
  METHODS
  The examined group consisted of 122 patients: 37 on regular haemodialysis (HD), 23 on peritoneal dialysis (PD) and 62 on conservative treatment with CKD stages 3-5 (CKD3-5). The activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione transpherase (GST) in platelets were obtained using kinetic methods. The spectrophotometric method established the concentrations of reduced glutathione (GSH).
  
  
  RESULTS
  SOD activity in PD differs significantly from CKD3-5 (4.96 vs 1.66; p < 0.0001). CAT activity assessed in PD and CKD3-5 was significantly different from HD (0.82 and 0.8 vs 0.52 before and 0.35 after HD, respectively). GST activity reached the highest value in PD (1.62), and it was significantly different from CKD3-5 (0.23) and HD before haemodialysis (0.11). During haemodialysis therapy, there was a considerable increase in GST activity (0.11 vs 0.3; p = 0.02) and decrease in SOD activity (from 3.41 to 2.27; p = 0.01). The highest GSH concentrations were obtained in CKD3-5 and differ significantly from HD (4.12 vs 2.01; p = 0.02).
  
  
  CONCLUSIONS
  The type of treatment, age and duration of renal replacement therapy determined significant changes in platelet antioxidative enzymes activities and concentration of GSH, which may enhance the thrombotic complications. PD is associated with lower platelet oxidative stress.
authors.affiliation: Department of Nephrology, Transplantology and Internal Medicine, Pomeranian Medical University, Powstancow Wielkopolskich 72, 70-111, Szczecin, Poland. asia_stepniewska@wp.pl.
authors.forename: Joanna
authors.initials: J
authors.lastname: Stępniewska
authors.affiliation: Department of Medical Analysis, Pomeranian Medical University, Szczecin, Poland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Dołęgowska
authors.affiliation: Department of Medical Analysis, Pomeranian Medical University, Szczecin, Poland.
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Cecerska-Heryć
authors.affiliation: Department of Nephrology, Transplantology and Internal Medicine, Pomeranian Medical University, Powstancow Wielkopolskich 72, 70-111, Szczecin, Poland.
authors.forename: Edyta
authors.initials: E
authors.lastname: Gołembiewska
authors.affiliation: Department of Nephrology, Transplantology and Internal Medicine, Pomeranian Medical University, Powstancow Wielkopolskich 72, 70-111, Szczecin, Poland.
authors.forename: Alicja
authors.initials: A
authors.lastname: Malinowska-Jędraszczyk
authors.affiliation: Department of Nephrology, Transplantology and Internal Medicine, Pomeranian Medical University, Powstancow Wielkopolskich 72, 70-111, Szczecin, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Marchelek-Myśliwiec
authors.affiliation: Department of Nephrology, Transplantology and Internal Medicine, Pomeranian Medical University, Powstancow Wielkopolskich 72, 70-111, Szczecin, Poland.
authors.forename: Kazimierz
authors.initials: K
authors.lastname: Ciechanowski
mesh_terms: D000368:Aged; D000975:Antioxidants / Q000032:analysis; D015415:Biomarkers / Q000032:analysis; D001792:Blood Platelets / Q000201:enzymology*; D002374:Catalase / Q000032:analysis*; D003430:Cross-Sectional Studies; D005260:Female; D005979:Glutathione Peroxidase / Q000032:analysis*; D005982:Glutathione Transferase / Q000032:analysis*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000201:enzymology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress; D011379:Prognosis; D017582:Renal Replacement Therapy; D013053:Spectrophotometry; D013482:Superoxide Dismutase / Q000032:analysis
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005982:Glutathione Transferase
keywords: Antioxidant enzymes; Chronic kidney disease; Haemodialysis; Oxidative stress; Peritoneal dialysis; Platelets