title: Metabolomics Reveals Dynamic Metabolic Changes Associated with Age in Early Childhood.
abstract: OBJECTIVE
  A detailed understanding of the metabolic processes governing rapid growth in early life is still lacking. The aim of this study was to investigate the age-related metabolic changes in healthy children throughout early childhood.
  
  
  METHODS
  Healthy children from a birth cohort were enrolled in this study from birth through 4 years of age. Urinary metabolites were assessed at 6 months, and 1, 2, 3, and 4 yr of age by using 1H-nuclear magnetic resonance (NMR) spectroscopy coupled with multivariate statistical analysis including principal components analysis (PCA) and partial least-squares discriminant analysis (PLS-DA). Metabolic pathway analysis was performed using the MetPA web tool.
  
  
  RESULTS
  A total of 105 urine samples from 30 healthy children were collected and analyzed. Metabolites contributing to the discrimination between age groups were identified by using supervised PLS-DA (Q2 = 0.60; R2 = 0.66). A significantly higher urinary trimethylamine N-oxide (TMAO) and betaine level was found in children aged 6 months. Urinary glycine and glutamine levels declined significantly after 6 months of age and there was a concomitant compensatory increase in urinary creatine and creatinine. Metabolic pathway analysis using MetPA revealed similar nitrogen metabolism associated energy production across all ages assessed. Pathways associated with amino acid metabolism were significantly different between infants aged 6 months and 1 year, whereas pathways associated with carbohydrate metabolism were significantly different between children at ages 2 and 3 years.
  
  
  CONCLUSIONS
  Urine metabolomics ideally represents dynamic metabolic changes across age. Urinary metabolic profiles change significantly within the first year of life, which can potentially provide crucial information about infant nutrition and growth.
authors.affiliation: Department of Pediatrics, Chang Gung Memorial Hospital at Keelung, and Chang Gung University, Taoyuan, Taiwan.|Community Medicine Research Centre, Chang Gung Memorial Hospital, Keelung, Taiwan.|Department of Pediatrics, Chang Gung Memorial Hospital at Linkou, and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Chih-Yung
authors.initials: CY
authors.lastname: Chiu
authors.affiliation: Community Medicine Research Centre, Chang Gung Memorial Hospital, Keelung, Taiwan.|Department of Pediatrics, Chang Gung Memorial Hospital at Linkou, and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Kuo-Wei
authors.initials: KW
authors.lastname: Yeh
authors.affiliation: Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital at Linkou, and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Gigin
authors.initials: G
authors.lastname: Lin
authors.affiliation: Community Medicine Research Centre, Chang Gung Memorial Hospital, Keelung, Taiwan.
authors.forename: Meng-Han
authors.initials: MH
authors.lastname: Chiang
authors.affiliation: Department of Nutrition Therapy, Chang Gung Memorial Hospital, Keelung, Taiwan.
authors.forename: Shu-Chen
authors.initials: SC
authors.lastname: Yang
authors.affiliation: Department of Nutrition Therapy, Chang Gung Memorial Hospital, Keelung, Taiwan.
authors.forename: Wei-Ju
authors.initials: WJ
authors.lastname: Chao
authors.affiliation: Community Medicine Research Centre, Chang Gung Memorial Hospital, Keelung, Taiwan.|Department of Pediatrics, Chang Gung Memorial Hospital at Linkou, and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Tsung-Chieh
authors.initials: TC
authors.lastname: Yao
authors.affiliation: Department of Pediatrics, Chang Gung Memorial Hospital at Keelung, and Chang Gung University, Taoyuan, Taiwan.|Community Medicine Research Centre, Chang Gung Memorial Hospital, Keelung, Taiwan.
authors.forename: Ming-Han
authors.initials: MH
authors.lastname: Tsai
authors.affiliation: Department of Pediatrics, Chang Gung Memorial Hospital at Keelung, and Chang Gung University, Taoyuan, Taiwan.|Community Medicine Research Centre, Chang Gung Memorial Hospital, Keelung, Taiwan.
authors.forename: Man-Chin
authors.initials: MC
authors.lastname: Hua
authors.affiliation: Department of Pediatrics, Chang Gung Memorial Hospital at Keelung, and Chang Gung University, Taoyuan, Taiwan.|Community Medicine Research Centre, Chang Gung Memorial Hospital, Keelung, Taiwan.
authors.forename: Sui-Ling
authors.initials: SL
authors.lastname: Liao
authors.affiliation: Community Medicine Research Centre, Chang Gung Memorial Hospital, Keelung, Taiwan.|Department of Pediatrics, Chang Gung Memorial Hospital at Linkou, and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Shen-Hao
authors.initials: SH
authors.lastname: Lai
authors.affiliation: Graduate Institute of Medical Biotechnology, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Mei-Ling
authors.initials: ML
authors.lastname: Cheng
authors.affiliation: Community Medicine Research Centre, Chang Gung Memorial Hospital, Keelung, Taiwan.|Department of Pediatrics, Chang Gung Memorial Hospital at Linkou, and Chang Gung University, Taoyuan, Taiwan.
authors.forename: Jing-Long
authors.initials: JL
authors.lastname: Huang
mesh_terms: D000375:Aging / Q000378:metabolism* / Q000652:urine; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D055432:Metabolomics