Plasma amino acid profiles in healthy East Asian subpopulations living in Japan

Objectives 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 -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 -aminobutyric acid concentrations were significantly associated with age, BMI, and Chinese subpopulation, respectively. Conclusion 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. (c) 2015 The Authors American Journal of Human Biology Published by Wiley Periodicals, Inc.