PCK1 and obesity due to melanocortin 4 receptor deficiency: Pck1 is a regulator of the energy metabolism and gluconeogenesis in the liver, and its imbalance is related to metabolic diseases, such as diabetes, obesity and insulin resistance, while there is also a certain correlation between PPARγ and Pck1 (Beale et al., 2007; Tuo et al., 2019).