Eventually, we created a multivariable linear regression model, expressed by the combination of each variable and the corresponding coefficient, namely PDE1C = -0.004* p_Firmicutes + 3.059*DL-Glutamine − 571.6*Epiandrosterone + 206.5*3-Hydroxypicolinic-acid (Fig. 8E).This model suggested that the plasma metabolites Epiandrosterone, 3-Hydroxypicolinic_acid, Glutamine_D, and the gut microbiota p_Firmicutes may synergistically impact the expression levels of the PDE1C gene in the blood of obese children, promoting the onset and development of obesity and its associated complications. Here, PDE1C is linked to Obesity.