INS and obesity due to melanocortin 4 receptor deficiency: In the same vein in this study, significant changes were found in the expression levels of AMPK and PI3K-Akt, which are connected to obesity and diabetes [34,35], as well as the insulin signaling pathway-related genes in the liver and the intestine, indicating that common carp have a complex set of gene regulation networks in response to the influence of a hypoxic environment.