title: Enhanced platelet apoptosis in chronic uremic patients.
abstract: BACKGROUND
  There is a paucity of research on platelet apoptosis and its contribution to platelet dysfunction in uremic patients. The present study sought to analyze platelets apoptosis in uremic patients who underwent different dialysis modalities.
  
  
  METHODS
  Sixteen chronic uremic patients (5 on hemodialysis, 6 on peritoneal dialysis and 5 on non-dialysis) and 16 controls were studied. Platelet-rich plasma was detected for apoptotic events including depolarization of mitochondrial inner membrane potential (ΔΨm), phosphatidylserine (PS) exposure, activation of caspases-3 and Bcl-2 family proteins variations by Flow Cytometry or by Western-Blot. Washed normal platelets were incubated with normal or uremic platelet poor plasma and then were detected apoptotic events. Platelets function was assessed by ristocetin induced aggregative function test.
  
  
  RESULTS
  Compared to controls, uremic platelets demonstrated greater apoptosis for the ΔΨm depolarization (43.48 ± 9.58 vs. 52.76 ± 15.36, p = 0.005) as well as PS exposure (1.36 ± 0.51 vs. 0.99 ± 0.27, p < 0.001). There was no significant difference among different treatment groups (for the ΔΨm depolarization f = 0.16, p = 0.85; for the PS exposure f = 1.06, p = 0.36). Western Blot analyses showed caspase-3 activation and pro-apoptotic Bcl-2 family proteins expression. Platelets exposed to uremic plasma exhibited distinct apoptosis phenomena. Ristocetin induced platelet aggregation was markedly diminished in uremic patients and treated platelets.
  
  
  CONCLUSIONS
  These findings indicate that platelets are incurred apoptosis in uremia patients. Uremic plasma accelerates apoptosis of normal platelets, resulting in a dysfunctional pattern of platelets in uremia. Uremic platelets apoptosis has no relationship with dialysis modality.
authors.affiliation: Department of Nephrology, The First Affiliated Hospital of Soochow University , Suzhou , China.
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Zhaoyue
authors.initials: Z
authors.lastname: Wang
authors.forename: Tongling
authors.initials: T
authors.lastname: Ma
authors.forename: Guoyuan
authors.initials: G
authors.lastname: Lu
authors.forename: Rong
authors.initials: R
authors.lastname: Yan
authors.forename: Lili
authors.initials: L
authors.lastname: Zhao
authors.forename: Kun
authors.initials: K
authors.lastname: Deng
authors.forename: Kesheng
authors.initials: K
authors.lastname: Dai
mesh_terms: D000328:Adult; D017209:Apoptosis; D001792:Blood Platelets / Q000502:physiology*; D016022:Case-Control Studies; D005260:Female; D006470:Hemorrhage / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015539:Platelet Activation; D010974:Platelet Aggregation; D014511:Uremia / Q000097:blood* / Q000150:complications
keywords: Apoptosis; hemodialysis; peritoneal dialysis; platelets; uremia