title: Plasma amino acid profiles in healthy East Asian subpopulations living in Japan.
abstract: OBJECTIVE
  Profiles of plasma free amino acids (PFAAs) have been utilized as biomarkers to detect various diseases. However, few studies have investigated whether ethnicity or specific subpopulations within East Asia influence PFAA concentrations.
  
  
  METHODS
  A total of 95 healthy volunteers living in Japan, including 31 Japanese individuals, 36 Korean individuals and 28 Chinese individuals, were enrolled. Participants' PFAA levels were measured by high-performance liquid chromatography mass spectrometry, and the effects of factors such as sex, age, body mass index (BMI) and subpopulation on PFAA profiles were analyzed.
  
  
  RESULTS
  With the exception of glutamine and α-aminobutyric acid, there were no significant differences among the three examined subpopulations with respect to either the means or the distributions of PFAA concentrations. A multiple regression analysis revealed that most of the PFAA concentrations were significantly related to sex. Ornithine concentrations, glutamate concentrations, and glutamine and α-aminobutyric acid concentrations were significantly associated with age, BMI, and Chinese subpopulation, respectively.
  
  
  CONCLUSIONS
  The study results indicate that the contributions of subpopulation within East Asia to PFAA profiles are small, particularly relative to the contributions provided by sex.
authors.affiliation: Institute for Innovation, Ajinomoto Co., Inc, Kawasaki, Japan.
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Nakamura
authors.affiliation: Institute for Innovation, Ajinomoto Co., Inc, Kawasaki, Japan.
authors.forename: Natsumi
authors.initials: N
authors.lastname: Nishikata
authors.affiliation: Institute for Innovation, Ajinomoto Co., Inc, Kawasaki, Japan.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Kawai
authors.affiliation: Institute for Innovation, Ajinomoto Co., Inc, Kawasaki, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Imaizumi
authors.affiliation: Institute for Innovation, Ajinomoto Co., Inc, Kawasaki, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Miyano
authors.affiliation: Institute for Innovation, Ajinomoto Co., Inc, Kawasaki, Japan.
authors.forename: Maiko
authors.initials: M
authors.lastname: Mori
authors.affiliation: Institute for Innovation, Ajinomoto Co., Inc, Kawasaki, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamamoto
authors.affiliation: Department of R&D Planning, Ajinomoto Co., Inc, Tokyo, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Noguchi
mesh_terms: D000328:Adult; D000596:Amino Acids / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D002681:China / Q000208:ethnology; D002851:Chromatography, High Pressure Liquid; D005202:Asia, Eastern; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012016:Reference Values; D056910:Republic of Korea / Q000208:ethnology
chemical_list: D000596:Amino Acids; D015415:Biomarkers