The melanocortin system and insulin resistance in humans: insights from a patient with complete POMC deficiency and type 1 diabetes mellitus.
Int J Obes (Lond)
; 38(1): 148-51, 2014 Jan.
Article
em En
| MEDLINE
| ID: mdl-23649472
ABSTRACT
The central melanocortin system is essential for the regulation of long-term energy homeostasis in humans. Rodent experiments suggest that this system also affects glucose metabolism, in particular by modulating peripheral insulin sensitivity independently of its effect on adiposity. Rare patients with complete genetic defects in the central melanocortin system can provide insight into the role of this system in glucose homeostasis in humans. We here describe the eighth individual with complete proopiomelanocortin (POMC) deficiency and the first with coincidental concomitant type 1 diabetes, which provides a unique opportunity to determine the role of melanocortins in glucose homeostasis in human. Direct sequencing of the POMC gene in this severely obese patient with isolated adrenocorticotropic hormone deficiency identified a homozygous 5' untranslated region mutation -11C>A, which we find to abolish normal POMC protein synthesis, as assessed in vitro. The patient's insulin requirements were as expected for his age and pubertal development. This unique patient suggests that in humans the central melanocortin system does not seem to affect peripheral insulin sensitivity, independently of its effect on adiposity.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Pró-Opiomelanocortina
/
Resistência à Insulina
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Insuficiência Adrenal
/
Diabetes Mellitus Tipo 1
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Melanocortinas
/
Obesidade Infantil
/
Obesidade
Tipo de estudo:
Etiology_studies
/
Prognostic_studies
Limite:
Child
/
Humans
/
Male
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article