Low serum nesfatin-1 levels may be a contributing factor for monogenic obesity due to prohormone convertase 1 deficiency

Leptin, leptin receptor, proopiomelanocortin, prohormone convertase 1, melanocortin-4 receptor, melanocortin-3 receptor, brain-derived neurothrophic factor, neurotrophic tyrosine receptor kinase type 2, and single minded 1 genes, which are the genes that have been shown to cause monogenic obesity, are related to the leptin-melanocortin system. Congenital prohormone convertase 1 deficiency is a very rare syndrome characterized by early-onset obesity, small intestinal dysfunction, impaired glucose homeostasis, and disrupted prohormone processing. Obesity phenotype seen in this syndrome is known to be due to reduced melanocortin signaling in the hypothalamus which arises as a result of impaired processing of proopiomelanocortin. However, prohormone convertase 1 cleaves a number of other neuropeptides involved in feeding behavior and impaired cleavage of these neuropeptides, particularly NUCB2/nesfatin, may be a contributing factor for development of obesity in these cases. Until now, in prohormone convertase 1 deficient patients, low serum nesfatin-1 levels have not been mentioned to be a possible cause of obesity, we suggest that in these patients low levels of anorexigenic peptid nesfatin-1 might be another facilitating factor for development of obesity.