Serum metabolites associated with increased insulin resistance and low cardiorespiratory fitness in overweight adolescents

Obesity affects metabolism, increasing the risk of developing non-communicable diseases in adolescence, due to excess adipose tissue and low cardiorespiratory fitness (CRF). The metabolomics approach allows the elucidation of metabolites, which may have the concentrations altered by several factors, such as body composition (BC). We aimed to analyze the metabolomic profile of normal-weight and overweight adolescents and associate the metabolites with clinical markers related to BC, insulin resistance (IR), and CRF.The sample was composed of 57 adolescents and divided into two groups: the normal-weight group (NWG, n = 24) and the overweight group (OWG, n = 33). They underwent blood collection and anthropometric, BC, and CRF assessment. Blood serum samples were analyzed by 1H-NMR spectroscopy (600 MHz). The OWG presented higher values of body weight (BW), body mass index (BMI), waist circumference (WC), fasting glucose, insulin, IR, cholesterol, and percentage of fat mass (%FM) and lower levels of peak oxygen consumption (VO2 peak) compared with the NWG. The OWG presented lower concentrations of 3-hydroxyisovalerate, glutamate, and methionine as well as higher concentrations of aspartate, asparagine, creatine, glycerol, myo-inositol, proline, pyruvate, tyrosine, and valerate compared with the NWG. The concentrations of glutamate, myo-inositol, creatine, methionine, and valerate correlated with %FM; pyruvate and valerate positively correlated with IR; and glutamate, tyrosine, and valerate negatively correlated with CRF.Changes in the BC lead to changes in the metabolomic profile of adolescents, and the altered metabolites are associated with increased IR and low CRF. These results indicate new targets for health monitoring and prevention of cardiovascular and metabolic diseases in adolescents.