1: Cell Metab. 2008 Nov;8(5):437-45.

Apelin stimulates glucose utilization in normal and obese insulin-resistant mice.

Dray C, Knauf C, Daviaud D, Waget A, Boucher J, Buléon M, Cani PD, Attané C,
Guigné C, Carpéné C, Burcelin R, Castan-Laurell I, Valet P.

Institut National de la Santé et de la Recherche Médicale, U858, Toulouse,
France.

Adipose tissue (AT) secretes several adipokines that influence insulin
sensitivity and potentially link obesity to insulin resistance. Apelin, a peptide
present in different tissues, is also secreted by adipocytes. Apelin is
upregulated in obese and hyperinsulinemic humans and mice. Although a tight
relation exists between the regulation of apelin and insulin, it remains largely 
unknown whether apelin affects whole-body glucose utilization. Herein, we show
that in chow-fed mice, acute intravenous injection of apelin has a powerful
glucose-lowering effect associated with enhanced glucose utilization in skeletal 
muscle and AT. Through in vivo and in vitro pharmacological and genetic
approaches, we demonstrate the involvement of endothelial NO synthase,
AMP-activated protein kinase, and Akt in apelin-stimulated glucose uptake in
soleus muscle. Remarkably, in obese and insulin-resistant mice, apelin restored
glucose tolerance and increased glucose utilization. Apelin could thus represent 
a promising target in the management of insulin resistance.


PMID: 19046574 [PubMed - in process]

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