XBP1 and obesity due to melanocortin 4 receptor deficiency: To investigate the association between obesity-induced inflammation and ER stress, we measured the mRNA levels of ER stress markers, including Total X-box Binding Protein 1 (TXbp1), Binding Immunoglobulin Protein (Bip), C/EBP Homologous Protein (Chop), and Activating Transcription Factor 4 (Atf4) in WAT of mice subjected to LF or HF diets for 14 weeks.