To identify upstream factors leading to the increased expression of TRIP-Br2 in visceral fat during obesity, we incubated differentiated 3T3-L1 adipocytes with serum obtained from mice fed either chow diet (CD) or 12 weeks of HFD and observed that HFD serum significantly upregulated Trip-br2 expression in adipocytes compared with CD serum (Fig. 1c). This evidence concerns the gene SERTAD2 and obesity due to melanocortin 4 receptor deficiency.