Glycation and carbonyl stress produced by methylglyoxal (MG) as a consequence of triose flux in glycolysis has been implicated in the etiology of metabolic syndrome and diabetes complications. An integrated estimation of MG flux is provided by measuring concentrations of its catabolite D-lactate in serum. However, no studies have explored the pathway in childhood obesity.
Objective: Study serum concentrations of D-lactate and low molecular weight advanced glycation end-products (LMWAGE) in lean vs adolescents with obesity.
Material and Methods: We conducted a cross-sectional study of 30 lean and 30 obese adolescents between the ages of 15-19 years. D-lactate was measured kinetically in serum ultrafiltrates by an adaptation of a colorimetric method from Sigma. Total and LMW-AGEs were measured by fluorescence (Excitation: λ 370 nm, Emission: λ 440 nm). The Ethical Committee of the Institution approved this study and informed consent was obtained from the participant adolescents and their parents.
Results: The obesity group showed significantly (* p < 0.01, ** p < 0.001) higher levels of: % body fat 35.0 ± 9**, systolic BP 116.0 ± 8.1 mmHg** and diastolic BP, 72.9 ± 7.1*mmHg, waist 96.1 ± 11.6 cm** and hip circumferences 110.2 ± 8 cm**, HbA1c 5.1 ± 0.6*. D-lactate was 4.5 +/- 2.5 nmol/l in controls vs 7.4 +/- 4.2 vs. nmol/l in obese subjects **. LMW/total AGE were 0.48 (0.44-052) AU in controls vs 0.61 (0.55-0.67) AU in obese subjects**.
Conclusions: D-lactate levels and LMW-AGEs are higher (64% and 27% respectively) in adolescents with obesity as compared to lean controls. Our data is compatible with the presence of an increased production of MG associated with protein modification that results in LMW-AGE (partial proteolysis of AGE proteins) increases in serum. This increased carbonyl stress may be of etiological significance. Sources of Research Support: Project supported by DAIP Universidad de Guanajuato (project 011/2015) and Touro University
Rodriguez Mortera, R., Bains, Y., Caccavello, R., Luevano, C., Garay-Sevilla, M. E., & Gugliucci, A. (2017). D-lactate and low molecular AGEs are elevated in obese adolescents: Evidence for carbonyl stress in adolescent obesity. Journal of Obesity and Chronic Diseases, 1(Suppl. 2), S35.