Obesity and diabetes related plasma amino acid alterations.

OBJECTIVES

The objective of the study is to evaluate whether plasma amino acid (AA) differences are related with obesity or diabetes.

DESIGN AND METHODS

In 126 diabetes and 100 non-diabetes participants, the plasma concentrations of 42 (AAs) were analyzed with a liquid chromatography tandem mass spectrometry technology (LC-MS/MS). Both groups were divided into obese and lean individuals and we compared intra- and inter-group differences between the groups.

RESULTS

In obese non-diabetic participants, 19 AA plasma concentrations were different compared to lean non-diabetic individuals, from which 15 were essential AAs, whereas in the diabetic group only three AAs differed in the obese compared to the lean patients. When comparing the overall AA differences between diabetics and non-diabetics, 16 AA concentrations were enhanced and 11 AA concentrations were reduced in the diabetic patients. A multivariate linear regression analysis revealed correlations between: FBG and Cystathionine, Proline and Citrulline; HbA1c and Glycine, Proline and Sarcosine; Cholesterol and Serine, β-alanine, Proline and Cystathionine; HDL-C and β-alanine, 1-methylhistidine and Proline; and LDL-C and α-Amino n-butyric acid and Hydroxyproline. Triglycerides were related with γ-aminobutyric acid, Serine and Alanine. Fasting insulin was related with 3-methylhistidine, Asparagine, Alanine, γ-aminobutyric acid and Cystathionine.

CONCLUSIONS

The concentrations of 19 plasma AAs differed between non-diabetic obese and lean individuals, which were mostly superimposed by diabetes. Between diabetic and non-diabetic participants plasma AA concentration differences were obvious and some of these alterations were correlated to other factors like blood glucose, lipids, insulin and hemoglobin status.