title: Urinary metabolome identifies signatures of oligozoospermic infertile men.
abstract: OBJECTIVE
  To identify the differential urinary metabolic pattern of oligozoospermic infertile men and to determine the potential biomarkers indicative of infertility.
  
  
  METHODS
  Observational study.
  
  
  METHODS
  University hospital.
  
  
  METHODS
  Totals of 158 fertile volunteers and 135 oligozoospermic infertile men.
  
  
  METHODS
  None.
  
  
  METHODS
  Urinary metabolic profiles were acquired with the use of liquid chromatography/mass spectrometry. Potential oligozoospermic biomarkers were screened from orthogonal projections to latent structures discriminant analysis and further evaluated by receiver operating characteristic analysis. The Spearman correlations between the individual sets of biomarkers and between biomarkers and sperm parameters were investigated. The disrupted biologic pathways which the biomarkers were involved in also were analyzed.
  
  
  RESULTS
  Oligozoospermic infertile men could be differentiated from fertile control subjects based on altered urinary metabolic profiles. A total of ten potential biomarkers were screened and tentatively identified. Among those, decreased acylcarnitines, aspartic acid, and leucylproline and increased adenine and methylxanthine were strongly associated with oligozoospermic risk. Many biomarkers were associated with sperm concentration and amplitude of lateral head displacement. The combined pattern of acetylcarnitine, carnitine C3:1, and aspartic acid provided moderate diagnostic power.
  
  
  CONCLUSIONS
  Urinary metabolomics identified unique metabolic pattern of oligozoospermic infertility. The potential biomarkers suggested that oligozoospermia may be tightly associated with energy consumption and antioxidant defenses in spermatogenesis.
authors.affiliation: Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Chemistry, Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, People's Republic of China.
authors.forename: Zhenzhen
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Key Laboratory of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, Nanjing, People's Republic of China.
authors.forename: Minjian
authors.initials: M
authors.lastname: Chen
authors.affiliation: Key Laboratory of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, Nanjing, People's Republic of China.
authors.forename: Yankai
authors.initials: Y
authors.lastname: Xia
authors.affiliation: Centre for Biophotonics, Lancaster Environment Centre, Lancaster University, Lancaster, United Kingdom.
authors.forename: Francis L
authors.initials: FL
authors.lastname: Martin
authors.affiliation: Department of Chemistry, Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Hang
authors.affiliation: Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, People's Republic of China. Electronic address: hqshen@iue.ac.cn.
authors.forename: Heqing
authors.initials: H
authors.lastname: Shen
mesh_terms: D000328:Adult; D019540:Area Under Curve; D015415:Biomarkers / Q000652:urine; D016022:Case-Control Studies; D002853:Chromatography, Liquid; D016002:Discriminant Analysis; D004734:Energy Metabolism; D005298:Fertility; D006785:Hospitals, University; D006801:Humans; D008297:Male; D055432:Metabolomics / Q000379:methods; D009845:Oligospermia / Q000175:diagnosis / Q000503:physiopathology / Q000652:urine*; D018384:Oxidative Stress; D011237:Predictive Value of Tests; D012372:ROC Curve; D055101:Semen Analysis; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013091:Spermatogenesis; D013094:Spermatozoa / Q000378:metabolism* / Q000473:pathology; D055815:Young Adult
chemical_list: D015415:Biomarkers
keywords: Male infertility; metabolomics; oligozoospermia; urine