Plasma amino acids by age and gender in Hangzhou, Eastern China.

Background and objectives: Amino acids (AAs) are crucial nutrients and fundamental building blocks of organisms that can be utilized to assess nutritional status and detect diseases. However, insufficient information has been reported on plasma AA in the Eastern Chinese population.

Methods and study design: 1859 persons who underwent physical examination in our hospital from January to December 2020 were enrolled. Plasma AA levels were determined by ultra-performance liquid chromatography mass spectrometry (UPLC-MS/MS.), and the effects of age and sex on 19 plasma AA profiles were analyzed. The Python language was used for data analysis and graphic visualization.

Results: Plasma arginine, proline, threonine, as-paragine, phenylalanine, and glycine in males, and plasma lysine, leucine, proline, valine, isoleucine, alanine, tyrosine, phenylalanine, and hydroxyproline levels in females increased with age. The 2-aminobutyric acid and serine levels in both sexes, and isoleucine, valine, leucine, and histidine levels in males decreased with age. Glycine level was higher in females than in males, and other 17 AAs except arginine and aspartate were higher in males than in females.

Conclusions: Our study indicated that plasma AA levels can reflect the nutritional status and dietary structure of the population, with high obesity rate and high incidence of chronic diseases in eastern China. Age has certain effects on plasma AA levels, especially compared with sex.