title: Influence of hemodialysis membrane permeability on serum levels of advanced glycation end products (AGEs) and homocysteine metabolites.
abstract: BACKGROUND
  [corrected] Advanced glycation end products (AGEs), total homocysteine (tHcy) and the homocysteine metabolites cystathionine (Cysta) and dimethylglycine (DMG) are increased in serum of patients with end-stage renal disease. The aim of this prospective randomized study was to compare the efficacy of polysulfone high-flux vs. polysulfone low-flux hemodialysis (HD) treatment regarding removal of AGEs, tHcy, Cysta and DMG.
  
  
  METHODS
  Twenty-nine patients on chronic HD treatment were randomly assigned to 2 groups in a 3-period 2-treatment design with low flux (A)--high flux (B)--low flux (A) for group I and B-A-B for group II, 6 weeks each period. The following parameters were measured in pre- and postdialytic serum samples at baseline and the end of each period: total serum fluorescence, Nepsilon-carboxymethyllysine (CML), free and protein-bound pentosidine, tHcy, Cysta and DMG.
  
  
  RESULTS
  There was increased removal of free pentosidine during high-flux HD treatment compared to low-flux HD treatment, attaining significance between the second and third treatment periods (group 1: 86.0 +/- 4.7% vs. 79.2 +/- 8.8%, p = 0.007; group II: 84.0 +/- 6.3% vs. 79.8 +/- 9.8%, p = 0.049 for high vs. low flux). The intradialytic reduction rates for total serum fluorescence, tHcy, Cysta, DMG did not differ between high- and low-flux HD treatment. Protein-bound pentosidine and CML did not decrease during the dialysis sessions, neither with high-flux nor with low-flux HD membrane. Despite a strong decrease during single HD session, the predialytic levels of free pentosidine, tHcy, Cysta and DMG remained unchanged during the study period both for high- and low-flux HD treatment.
  
  
  CONCLUSIONS
  The more pronounced effect of high-flux dialysis on the removal rate of free pentosidine, found in this randomized crossover study, could not translate into a significant difference in predialysis levels after a 6-week treatment period. We could not find any differences between polysulfone high- and low-flux membranes for lowering predialytic serum concentrations of the measured AGEs, which are mainly bound on albumin.
authors.affiliation: Department of Internal Medicine III, Friedrich Schiller University, Jena, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Klemm
authors.forename: C
authors.initials: C
authors.lastname: Franke
authors.forename: M
authors.initials: M
authors.lastname: Busch
authors.forename: A
authors.initials: A
authors.lastname: Müller
authors.forename: S
authors.initials: S
authors.lastname: Franke
authors.forename: D
authors.initials: D
authors.lastname: Lang
authors.forename: J
authors.initials: J
authors.lastname: Passlick-Deetjen
authors.forename: G
authors.initials: G
authors.lastname: Stein
mesh_terms: D001120:Arginine / Q000031:analogs & derivatives* / Q000097:blood; D018592:Cross-Over Studies; D003540:Cystathionine / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005453:Fluorescence; D017127:Glycation End Products, Advanced / Q000097:blood*; D006710:Homocysteine / Q000378:metabolism*; D006801:Humans; D007688:Kidneys, Artificial; D008239:Lysine / Q000031:analogs & derivatives* / Q000097:blood; D008297:Male; D008567:Membranes, Artificial; D008875:Middle Aged; D011108:Polymers; D011446:Prospective Studies; D006435:Renal Dialysis / Q000295:instrumentation* / Q000379:methods; D012521:Sarcosine / Q000031:analogs & derivatives* / Q000097:blood*; D013450:Sulfones
chemical_list: D017127:Glycation End Products, Advanced; D008567:Membranes, Artificial; D011108:Polymers; D013450:Sulfones; D006710:Homocysteine; C017662:polysulfone P 1700; D003540:Cystathionine; C025138:dimethylglycine; D001120:Arginine; C062187:pentosidine; D008239:Lysine; D012521:Sarcosine