Background: Circulating asprosin is a newly discovered adipokine that triggers the release of hepatic glucose stores and increases appetite. Asprosin levels are elevated in adult obese men as well as in mice, and reductions in asprosin protect against the hyperinsulinism associated with metabolic syndrome in mice with diet-induced obesity, which indicates a potential therapeutic role of asprosin in obesity and type 2 diabetes. Objectives: Few data on asprosin in children are available, which is why this study aimed to assess concentrations of fasting asprosin, as well as its relationship to parameters of glucose and lipid metabolism, in children. Methods: Data on clinical and metabolic parameters were collected from 40 healthy normal-weight and 47 obese children. Circulating asprosin levels were measured using an ELISA. Results: The concentrations of fasting asprosin were lower in the obese children (9.24 +/- 4.11 ng/mL) than in the normal-weight controls (12.33 +/- 4.18 ng/mL, p < 0.001). When comparing the two groups by sex, both the boys and the girls showed similar trends. In within-group comparison, the asprosin levels were lower in boys than in girls only in the obese group (8.13 +/- 4.10 vs. 10.61 +/- 3.78 ng/mL, p = 0.013) but not in the control group. Interestingly, asprosin was correlated with ALT after adjusting for age and sex in all participants; in boys, asprosin was correlated with BMI, HOMA-IR, insulin, and HDL after adjusting for age. Conclusions: Concentrations of asprosin were significantly lower in obese children than in normal-weight children, and there was a gender difference in asprosin concentration. Our results suggest a complex role for asprosin in energy metabolism. (C) 2019 S. Karger AG, Basel