In addition, since obesity is also considered a low-level chronic inflammatory state characterized by the presence of inflammatory factors and infiltration of immune cells into adipocytes [108], many studies have reported that RBP4 is associated with a variety of inflammatory markers, including C-reactive protein, interleukin-6, tumor necrosis factor, and various cytokines [87, 109]. This evidence concerns the gene RBP4 and obesity due to melanocortin 4 receptor deficiency.