IL1B and obesity due to melanocortin 4 receptor deficiency: According to the correlation analysis between the lipid metabolites and the mice phenotypes, we observed that total TGs which were enriched in HFD-fed mice were positively correlated while total PEs, which were cut down in HFD-fed mice, were negatively correlated with the obesity risk indicators and inflammation markers, such as plasma cholesterol and triglyceride, plasma ALT and AST, fasting glucose, bodyweight, liver weight and liver to bodyweight ratio, liver cholesterol, and triglyceride, liver Il1b, iBAT and iWAT weight (Fig. 3G, Supplementary Fig. S4C, and Supplementary Table S4).