Vaspin belongs to family of newly discovered adipokines besides others such as retinol-binding protein 4 (RBP4), dipeptidyl peptidase 4 (DPP-4), bone morphogenetic protein (BMP)-4, BMP-7, and progranulin, recently implicated in various aspects of obesity [156]. Here, RBP4 is linked to obesity due to melanocortin 4 receptor deficiency.