IL18 and obesity due to melanocortin 4 receptor deficiency: The inhibitory effects of IL-18 on liver lipid storage and fibrosis may arise from its direct regulation of lipid homeostasis, including anti-hypercholesterolemia and anti-hypertriglyceridemia effects (Murphy et al., 2016), as well as from indirect effects, such as anti-hyperphagia and resulting anti-obesity effects (Netea et al., 2006) and modulation of gut microbiota composition (Henao-Mejia et al., 2012).