title: Metabonomic analysis of rat urine ¹H magnetic resonance spectra based on different normalization methods.
abstract: OBJECTIVE
  To study metabonomics in the urine of rats of different genders by magnetic resonance (MR) with 2 normalization methods.
  
  
  METHODS
  Different normalization methods such as mean-centering not scaling (Ctr) and unit variance scaling (UV) were used before orthogonal to partial least squares discriminant analysis(OPLS-DA). Distinguished metabolites in the urine of different gender rats were analyzed by calculating the correlation coefficients.
  
  
  RESULTS
  The data normalized by Ctr before OPLS-DA analysis revealed high degree conception metabolites in the urine such as valine, alanine, acetate, ornithine, aminohippurate, phenylethylamine, cytosine, citrate, dimethylamine, allantoin, methylamine, fumarate and one unknown metabolite whose chemical shift was δ4.14. Data normalized by UV before OPLS-DA analysis revealed the above 12 high degree conception metabolites except citrate, and also low degree conception metabolites such as thiamine, creatinine, formate and one unknown metabolite whose chemical shift was δ2.92.
  
  
  CONCLUSIONS
  Unit variance scaling is a more effective normalization method in metabonomic analysis.
authors.affiliation: College of Pharmacy, Xinjiang Medical University, Urumqi 830011, China.
authors.forename: Batur
authors.initials: B
authors.lastname: Mamtimin
authors.forename: Ayshamgul
authors.initials: A
authors.lastname: Hasim
authors.forename: Chunli
authors.initials: C
authors.lastname: Chen
authors.forename: Halmurat
authors.initials: H
authors.lastname: Upur
mesh_terms: D000818:Animals; D005260:Female; D008297:Male; D055442:Metabolome; D055432:Metabolomics; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D010363:Pattern Recognition, Automated; D051381:Rats; D017208:Rats, Wistar; D014556:Urine / Q000737:chemistry*