title: Effect of leukocytospermia and processing by discontinuous density gradient on sperm nuclear DNA fragmentation and mitochondrial activity.
abstract: OBJECTIVE
  To assess the effect of leukocytospermia and semen processing on sperm DNA and mitochondria.
  
  
  METHODS
  Twenty-two patients with and 41 without leukocytospermia were included. Sperm DNA fragmentation was assessed by the Comet assay, and mitochondrial activity by a colorimetric method for active mitochondria. Semen was processed using Percoll, and motility, DNA fragmentation, and mitochondrial activity were analyzed pre- and post-processing.
  
  
  RESULTS
  No differences were observed in age, abstinence, volume, sperm morphology, progressive motility, concentration, and vitality (p>0.10). Variables were grouped according to time (pre- vs post-processing) and group (leukocytospermia vs non-leukocytospermia) because no interactions could be observed. Leukocytospermia was associated to increased DNA fragmentation, while semen processing led to a decrease in DNA fragmentation and to increased mitochondrial activity.
  
  
  CONCLUSIONS
  While semen processing selects sperm with higher rates of DNA integrity independent of the presence or absence of leukocytes in semen, samples without leukocytospermia present more sperm without DNA fragmentation. Semen processing also selects sperm with higher mitochondrial activity.
authors.affiliation: Department of Surgery, Division of Urology, Sao Paulo Federal University, R Cotoxó 424 ap 13, 05021-000, Sao Paulo, SP, Brazil. ro.fariello@yahoo.com.br
authors.forename: Roberta Maria
authors.initials: RM
authors.lastname: Fariello
authors.forename: Paula Toni
authors.initials: PT
authors.lastname: Del Giudice
authors.forename: Deborah Montagnini
authors.initials: DM
authors.lastname: Spaine
authors.forename: Renato
authors.initials: R
authors.lastname: Fraietta
authors.forename: Ricardo Pimenta
authors.initials: RP
authors.lastname: Bertolla
authors.forename: Agnaldo Pereira
authors.initials: AP
authors.lastname: Cedenho
mesh_terms: D000328:Adult; D002499:Centrifugation, Density Gradient; D020552:Comet Assay; D004247:DNA / Q000378:metabolism; D053938:DNA Fragmentation; D006801:Humans; D007248:Infertility, Male / Q000378:metabolism / Q000503:physiopathology; D007962:Leukocytes / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D008928:Mitochondria / Q000502:physiology*; D018384:Oxidative Stress; D012661:Semen / Q000378:metabolism; D055101:Semen Analysis; D013048:Specimen Handling; D013094:Spermatozoa / Q000378:metabolism*
chemical_list: D004247:DNA