Serum Branched Chain and Aromatic Amino Acids Are Associated to Overweight, Obesity and Metabolic Alterations in School‐Aged Children

Abstract

BackgroundChildhood overweight and obesity are risk factors for metabolic alterations that could ultimately lead to pathological states. Metabolomics has emerged as a powerful tool to identify biomarkers for metabolic alterations. Multiple metabolomics studies have associated childhood obesity to serum amino acids and acylcarnitines, particularly to an increase in branched chain amino acids (BCAA). Despite these findings, so far there are no studies evaluating the serum amino acid profile in Mexican children. Therefore we aimed to identify amino acids associated to overweight, obesity and its metabolic alterations in Mexican school‐aged children.MethodologyAnthropometric and biochemical measurements were conducted in 845 children (6–12 years old) from a cross‐sectional study in Mexico City. Targeted metabolomics was performed by mass spectrometry. Children were classified according to their BMI percentile (BMIp) as low weight (LW; BMIp<5th), normal weight (NW; 5th<BMIp<85th), overweight (OW; 85th<BMIp<95th) and obese (OB; 95th<BMIp).ResultsOW and OB children had higher serum levels of BCAA and aromatic amino acids (AA) than NW and LW children (p<0.001). BCAA and AA correlated with higher HOMA (r=0.11, p=0.002 and r=0.15, p<0.001, respectively) and serum triglycerides (r=0.18, p<0.001 and r=0.19, p<0.001, respectively), after adjusting for age, sex and BMI percentile. Since insulin resistance (IR) and hypertriglyceridemia (hTG) are the most common metabolic alterations in Mexican children, those with both abnormalities were classified as Metabolically Compromised (MC), while those with none of these as Metabolically Healthy (MH). In NW, BCAA and AA were higher in MC than in MH children (p<0.001), concomitant to an increase in adiposity, suggesting that the higher levels of amino acids could respond to the higher degree of adiposity. However in OW children, BCAA an AA were also higher in MC children than in MH children (p<0.002), despite same percentage of adiposity between these two groups. Previous studies have suggested that a dysfunctional adipose tissue plays a role in the accumulation of these amino acids in serum and, in the development of metabolic complications. Thus we hypothesize that in OW children the adipose tissue functionality could be playing a role in the presence of metabolic complications, however the latter requires further research.ConclusionsBCAA and AA are associated to higher degree of overweight, likely related to a higher adiposity. However, their association with IR and hTG seems to be related to other factors besides adiposity. This highlights the importance of BCAA and AA in differentiating MH children from MC children.Support or Funding InformationThis work was supported by CONACYT grant 248765 to SM‐R