title: Metabolites as novel biomarkers for childhood obesity-related traits in Mexican-American children.
abstract: OBJECTIVE
  Although newer approaches have identified several metabolites associated with obesity, there is paucity of such information in paediatric populations, especially among Mexican-Americans (MAs) who are at high risk of obesity. Therefore, we performed a global serum metabolite screening in MA children to identify biomarkers of childhood obesity.
  
  
  METHODS
  We selected 15 normal-weight, 13 overweight and 14 obese MA children (6-17 years) and performed global serum metabolite screening using ultra-performance liquid chromatography/quadruple orthogonal acceleration time of flight tandem micro mass spectrometer. Metabolite values were analysed to assess mean differences among groups using one-way analysis of variance, to test for linear trend across groups and to examine Pearson's correlations between them and seven cardiometabolic traits (CMTs): body mass index, waist circumference, systolic blood pressure, diastolic blood pressure, homeostasis model of assessment-insulin resistance, triglycerides and high-density lipoprotein cholesterol.
  
  
  RESULTS
  We identified 14 metabolites exhibiting differences between groups as well as linear trend across groups with nominal statistical significance. After adjustment for multiple testing, mean differences and linear trends across groups remained significant (P < 5.9 × 10(-5) ) for L-thyronine, bradykinin and naringenin. Of the examined metabolite-CMT trait pairs, all metabolites except for 2-methylbutyroylcarnitine were nominally associated with two or more CMTs, some exhibiting significance even after accounting for multiple testing (P < 3.6 × 10(-3) ).
  
  
  CONCLUSIONS
  To our knowledge, this study - albeit pilot in nature - is the first study to identify these metabolites as novel biomarkers of childhood obesity and its correlates. These findings signify the need for future systematic investigations of metabolic pathways underlying childhood obesity.
authors.affiliation: Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX, USA.
authors.forename: V S
authors.initials: VS
authors.lastname: Farook
authors.affiliation: Department of Plant Science/Department of Food Science, Penn State University, University Park, PA, USA.
authors.forename: L
authors.initials: L
authors.lastname: Reddivari
authors.affiliation: Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX, USA.
authors.forename: G
authors.initials: G
authors.lastname: Chittoor
authors.affiliation: Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX, USA.
authors.forename: S
authors.initials: S
authors.lastname: Puppala
authors.affiliation: Pediatrics-Endocrinology/Medicine -Cardiology/Medicine-Diabetes, University of Texas Health Science Center at San Antonio, TX, USA.
authors.forename: R
authors.initials: R
authors.lastname: Arya
authors.affiliation: Pediatrics-Endocrinology/Medicine -Cardiology/Medicine-Diabetes, University of Texas Health Science Center at San Antonio, TX, USA.
authors.forename: S P
authors.initials: SP
authors.lastname: Fowler
authors.affiliation: Public Health Sciences, Medical University of South Carolina, Charleston, SC, USA.
authors.forename: K J
authors.initials: KJ
authors.lastname: Hunt
authors.affiliation: Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Curran
authors.affiliation: Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX, USA.
authors.forename: A G
authors.initials: AG
authors.lastname: Comuzzie
authors.affiliation: Pediatrics-Endocrinology/Medicine -Cardiology/Medicine-Diabetes, University of Texas Health Science Center at San Antonio, TX, USA.
authors.forename: D M
authors.initials: DM
authors.lastname: Lehman
authors.affiliation: Pediatrics-Endocrinology/Medicine -Cardiology/Medicine-Diabetes, University of Texas Health Science Center at San Antonio, TX, USA.
authors.forename: C P
authors.initials: CP
authors.lastname: Jenkinson
authors.affiliation: Pediatrics-Endocrinology/Medicine -Cardiology/Medicine-Diabetes, University of Texas Health Science Center at San Antonio, TX, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Lynch
authors.affiliation: Pediatrics-Endocrinology/Medicine -Cardiology/Medicine-Diabetes, University of Texas Health Science Center at San Antonio, TX, USA.
authors.forename: R A
authors.initials: RA
authors.lastname: DeFronzo
authors.affiliation: Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX, USA.
authors.forename: J
authors.initials: J
authors.lastname: Blangero
authors.affiliation: Pediatrics-Endocrinology/Medicine -Cardiology/Medicine-Diabetes, University of Texas Health Science Center at San Antonio, TX, USA.
authors.forename: D E
authors.initials: DE
authors.lastname: Hale
authors.affiliation: Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX, USA.
authors.forename: R
authors.initials: R
authors.lastname: Duggirala
authors.affiliation: Department of Plant Science/Department of Food Science, Penn State University, University Park, PA, USA.
authors.forename: J
authors.initials: J
authors.lastname: Vanamala
mesh_terms: D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D018932:Chemokine CCL2 / Q000097:blood; D002648:Child; D008076:Cholesterol, HDL / Q000097:blood; D016207:Cytokines / Q000097:blood; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D015850:Interleukin-6 / Q000097:blood; D020738:Leptin / Q000097:blood; D008055:Lipids / Q000097:blood; D008297:Male; D017058:Mexican Americans; D063766:Pediatric Obesity / Q000097:blood* / Q000208:ethnology / Q000517:prevention & control; D012016:Reference Values; D012307:Risk Factors; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D014481:United States / Q000453:epidemiology; D055105:Waist Circumference
chemical_list: D015415:Biomarkers; D018932:Chemokine CCL2; D008076:Cholesterol, HDL; D016207:Cytokines; D007328:Insulin; D015850:Interleukin-6; D020738:Leptin; D008055:Lipids; D014409:Tumor Necrosis Factor-alpha; D002097:C-Reactive Protein
keywords: Biomarkers; Mexican-Americans; childhood obesity; metabolites