title: Association between Redox Status of Serum Albumin and Peritoneal Membrane Transport Properties in Patients on Peritoneal Dialysis.
abstract: BACKGROUND
  Albumin, the most abundant protein in the extracellular fluid, displays an important antioxidant activity. Increased levels of oxidized albumin levels (high human non-mercaptoalbumin (HNA) level) have been reported in the serum of patients with end-stage renal disease. In this study, we attempted to identify the albumin redox status in the serum of patients on peritoneal dialysis (PD) and examined the relationship between these proteins and the transport type of the peritoneal membrane and other clinical and laboratory variables.
  
  
  METHODS
  We performed a cross-sectional study of a cohort of 80 patients with end-stage renal disease receiving PD. Peritoneal transport characteristics were identified and after peritoneal equilibration test patients were grouped as high (high(H)/high-average (HA) group, n = 31) or low (low (L)/low-average (LA) group, n = 49) transporters. The redox state of human serum albumin was measured using high-performance liquid chromatography.
  
  
  RESULTS
  The fraction of human mercaptoalbumin (HMA) showed significantly higher values in patients with high transport status than those with low transport status (f(HMA) 64.0 ± 5.4 and 52.7 ± 10.4%, respectively). Our data showed that the H/HA transport characteristic was associated with lower albumin (3.76 ± 0.48 vs. 4.00 ± 0.35, p < 0.05), and lower levels of advanced oxidized protein product (p = 0.008) when compared with the L/LA type. A correlation analysis showed that there was a positive correlation between dialysate/plasma (D/P) creatinine and f(HMA) levels (r = 0.511, p < 0.0001), as well as hemoglobin levels r = 0.231, p = 0.044 and a negative correlation between D/P creatinine and serum albumin, cholesterol and LDL levels (r = -0.236, p = 0.039; r = -0.237, p = 0.038; r = -0.272, p = 0.018, respectively).
  
  
  CONCLUSIONS
  This study showed that higher serum levels of reduced albumin f(HMA) appear to be associated with high/high average peritoneal membrane transport characteristics in the incident PD patients.
authors.affiliation: Division of Renal Medicine, Tungs' Taichung Metroharbour Hospital, Taipei, Taiwan.
authors.forename: Paik Seong
authors.initials: PS
authors.lastname: Lim
authors.forename: Hung-Ping
authors.initials: HP
authors.lastname: Chen
authors.forename: Chang-Hsu
authors.initials: CH
authors.lastname: Chen
authors.forename: Ming Yin
authors.initials: MY
authors.lastname: Wu
authors.forename: Chuen Yuh
authors.initials: CY
authors.lastname: Wu
authors.forename: Tsai-Kun
authors.initials: TK
authors.lastname: Wu
mesh_terms: D000328:Adult; D000368:Aged; D000975:Antioxidants / Q000737:chemistry / Q000378:metabolism*; D001692:Biological Transport; D002784:Cholesterol / Q000097:blood; D015331:Cohort Studies; D003404:Creatinine / Q000097:blood; D003430:Cross-Sectional Studies; D005260:Female; D017127:Glycation End Products, Advanced / Q000097:blood; D006454:Hemoglobins / Q000378:metabolism; D018056:Hemorheology; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000473:pathology / Q000628:therapy; D007688:Kidneys, Artificial; D008077:Lipoproteins, LDL / Q000097:blood; D008297:Male; D008567:Membranes, Artificial; D008875:Middle Aged; D010084:Oxidation-Reduction; D010531:Peritoneal Dialysis, Continuous Ambulatory / Q000295:instrumentation*; D012044:Regression Analysis; D012709:Serum Albumin / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D017127:Glycation End Products, Advanced; D006454:Hemoglobins; D008077:Lipoproteins, LDL; D008567:Membranes, Artificial; D012709:Serum Albumin; C001702:mercaptoalbumin; D002784:Cholesterol; D003404:Creatinine