Significantly higher plasma concentrations of total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), aspartate transaminase (AST), and alanine transaminase (ALT) were found in the obese group, which indicated a systemic response to obesity that includes NAFLD (Fig. 1m, n). Here, GPT is linked to obesity due to melanocortin 4 receptor deficiency.