C-type natriuretic peptide is closely associated to obesity in Caucasian adolescents

CNP is a natural regulator of adipogenesis playing a role in the development of obesity in childhood. Aim of the study was to evaluate CNP plasma levels in normal-weight (N), overweight (OW) and obese adolescents (O). Eighty two subjects (age:12.8±2.4, years) without cardiac dysfunction were enrolled and CNP plasma levels were measured by RIA. NT-proBNP, MR-proANP, AGEs, reactive hyperemia index (RHI) and standard clinical chemistry parameters were also measured. O and OW adolescents had higher values of BMI and fat mass than N. CNP levels were significantly lower in OW:4.79[3.29-21.15] and O:3.81[1.55-13.4] than in N:13.21[7.6-37.8]; p<0.0001N vs O, p=0.0003N vs OW). LogCNP values correlated significantly and inversely with BMI z-score, FM%, TF% and circulating levels of CRP, insulin, total cholesterol, LDL, and triglycerides, in addition to an inverse relationship with skin AGEs and a direct correlation with RHI. LogCNP was also inversely associated with LogNT-proBNP and LogMR-proANP values. Using ROC analysis the risk of obesity resulted significantly (p≪0.0001) associated with CNP values (AUC=0.9724). These results suggest that CNP may play a more important role than BNP and ANP related peptides, as risk marker of obesity, in addition to its involvement in adipogenesis and endothelial dysfunction.