CBLN1 and obesity due to melanocortin 4 receptor deficiency: For example, it has been reported that the administration of myliocin, a potent inhibitor of the de novo synthesis of global sphingolipids, into rodent models of obesity improves insulin resistance, glucose homeostasis and liver steatosis.9,10 We also demonstrated that the synthesis of SM with SM synthase 2 and the phosphorylation of Cer with Cer kinase are related to high-fat diet-induced obesity, fatty liver and insulin resistance in mice.11,12