title: Proteomic analysis of human spermatozoa proteins with oxidative stress.
abstract: BACKGROUND
  Oxidative stress plays a key role in the etiology of male infertility. Significant alterations in the sperm proteome are associated with poor semen quality. The aim of the present study was to examine if elevated levels of reactive oxygen species cause an alteration in the proteomic profile of spermatozoa.
  
  
  METHODS
  This prospective study consisted of 52 subjects: 32 infertile men and 20 normal donors. Seminal ejaculates were classified as ROS+ or ROS- and evaluated for their proteomic profile. Samples were pooled and subjected to LC-MS/MS analysis through in-solution digestion of proteins for peptide characterization. The expression profile of proteins present in human spermatozoa was examined using proteomic and bioinformatic analysis to elucidate the regulatory pathways of oxidative stress.
  
  
  RESULTS
  Of the 74 proteins identified, 10 proteins with a 2-fold difference were overexpressed and 5 were underexpressed in the ROS+ group; energy metabolism and regulation, carbohydrate metabolic processes such as gluconeogenesis and glycolysis, protein modifications and oxidative stress regulation were some of the metabolic processes affected in ROS+ group.
  
  
  CONCLUSIONS
  We have identified proteins involved in a variety of functions associated with response and management of oxidative stress. In the present study we focused on proteins that showed a high degree of differential expression and thus, have a greater impact on the fertilizing potential of the spermatozoa. While proteomic analyses identified the potential biomarkers, further studies through Western Blot are necessary to validate the biomarker status of the proteins in pathological conditions.
authors.affiliation: Center for Reproductive Medicine, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Rakesh
authors.initials: R
authors.lastname: Sharma
authors.forename: Ashok
authors.initials: A
authors.lastname: Agarwal
authors.forename: Gayatri
authors.initials: G
authors.lastname: Mohanty
authors.forename: Alaa J
authors.initials: AJ
authors.lastname: Hamada
authors.forename: Banu
authors.initials: B
authors.lastname: Gopalan
authors.forename: Belinda
authors.initials: B
authors.lastname: Willard
authors.forename: Satya
authors.initials: S
authors.lastname: Yadav
authors.forename: Stefan
authors.initials: S
authors.lastname: du Plessis
mesh_terms: D002853:Chromatography, Liquid; D006801:Humans; D007248:Infertility, Male / Q000378:metabolism; D008297:Male; D018384:Oxidative Stress; D020543:Proteome / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012661:Semen / Q000378:metabolism; D055101:Semen Analysis; D013094:Spermatozoa / Q000378:metabolism*; D053719:Tandem Mass Spectrometry
chemical_list: D020543:Proteome; D017382:Reactive Oxygen Species