Ghrelin binding to serum albumin and its biological impact.
Mol Cell Endocrinol
; 436: 130-40, 2016 11 15.
Article
em En
| MEDLINE
| ID: mdl-27431015
ABSTRACT
Ghrelin is an octanoylated peptide hormone that plays a key role in the regulation of the body weight and glucose homeostasis. In plasma, ghrelin circulates bound to larger proteins whose identities are partially established. Here, we used size exclusion chromatography, mass spectrometry and isothermal titration microcalorimetry to show that ghrelin interacts with serum albumin. Furthermore, we found that such interaction displays an estimated dissociation constant (KD) in the micromolar range and involves albumin fatty-acid binding sites as well as the octanoyl moiety of ghrelin. Notably, albumin-ghrelin interaction reduces the spontaneous deacylation of the hormone. Both in vitro experiments-assessing ghrelin ability to inhibit calcium channels-and in vivo studies-evaluating ghrelin orexigenic effects-indicate that the binding to albumin affects the bioactivity of the hormone. In conclusion, our results suggest that ghrelin binds to serum albumin and that this interaction impacts on the biological activity of the hormone.
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Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Albumina Sérica
/
Grelina
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article