title: Evaluation of oxidative stress biomarkers in patients with chronic renal failure: a case control study.
abstract: BACKGROUND
  Oxidative stress is related to several diseases, including chronic renal insufficiency. The disequilibrium in the oxidant-antioxidant balance is the result of several metabolic changes. The majority of studies to-date have evaluated the grade of oxidative stress with a single biomarker, or a very limited number of them.
  
  
  RESULTS
  The present study used several important biomarkers to establish a score relating to oxidative stress status (glutathione S-transferase, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, reduced and oxidized glutathione, thiobarbituric acid reactive substances and hemolysis test). The score of oxidative stress (SOS) was then applied to a group of patients with renal insufficiency not on hemodialysis, and compared to healthy control individuals.The score for patients with chronic renal insufficiency was significantly different from that of the healthy control group (0.62 +/- 1.41 vs. -0.05 +/- 0.94; p < 0.001). The comparison between patients with chronic renal insufficiency and control individuals showed significant differences with respect to changes in the enzymatic antioxidant systems (glutathione S-transferase, glutathione reductase), non-enzymatic antioxidant system (oxidized glutathione) and oxidizability (hemolysis test) indicating significant oxidative stress associated with chronic renal insufficiency.
  
  
  CONCLUSIONS
  Patients with chronic renal insufficiency not on hemodialysis are susceptible to oxidative stress. The mechanisms that underlie this status are the consequence of changes in glutathione and related enzymes. The SOS scoring system is a useful biochemical parameter to evaluate the influence of oxidative stress on the clinical status of these patients.
authors.affiliation: Pharmacology Unit, Department of Basic Medical Sciences, Universitat Rovira i Virgili, Spain. montse.giralt@urv.cat.
authors.forename: Marta
authors.initials: M
authors.lastname: Romeu
authors.forename: Rosa
authors.initials: R
authors.lastname: Nogues
authors.forename: Luís
authors.initials: L
authors.lastname: Marcas
authors.forename: Vanesa
authors.initials: V
authors.lastname: Sánchez-Martos
authors.forename: Miquel
authors.initials: M
authors.lastname: Mulero
authors.forename: Alberto
authors.initials: A
authors.lastname: Martinez-Vea
authors.forename: Jordi
authors.initials: J
authors.lastname: Mallol
authors.forename: Montserrat
authors.initials: M
authors.lastname: Giralt