In this study, 3021 MRP down-regulated the protein expressions of p-IRE1α, BIP and XBP-1 in mouse liver tissues in model group, and inhibited ERS, thereby promoting lipid metabolism and alleviating obesity (Teunis, Nieuwdorp & Hanssen, 2022). Here, ERN1 is linked to obesity due to melanocortin 4 receptor deficiency.