Expanding role for the apelin/APJ system in physiopathology

J Physiol Biochem. 2007 Dec;63(4):359-73.


Apelin is a bioactive peptide known as the ligand of the G protein-coupled receptor APJ. Diverse active apelin peptides exist under the form of 13, 17 or 36 amino acids, originated from a common 77-amino-acid precursor. Both apelin and APJ mRNA are widely expressed in several rodent and human tissues and have functional effects in both the central nervous system and peripheral tissues. Apelin has been shown to be involved in the regulation of cardiovascular functions, fluid homeostasis, vessel formation and cell proliferation. More recently, apelin has been described as an adipocyte-secreted factor (adipokine), up-regulated in obesity. By acting as circulating hormone or paracrine factor, adipokines are involved in physiological regulations (fat depot development, energy storage, metabolism or eating behavior) or in the promotion of obesity-associated disorders (type 2 diabetes and cardiovascular dysfunctions). In this regard, expression of apelin gene in adipose tissue is increased by insulin and TNFalpha. This review will consider the main roles of apelin in physiopathology with particular attention on its role in energy balance regulation and in obesity-associated disorders.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Adipose Tissue / metabolism
  • Animals
  • Apelin
  • Apelin Receptors
  • Cardiovascular Diseases / etiology
  • Diabetes Mellitus, Type 2 / etiology
  • Humans
  • Intercellular Signaling Peptides and Proteins / metabolism
  • Intercellular Signaling Peptides and Proteins / physiology*
  • Ligands
  • Obesity / complications
  • Obesity / metabolism
  • RNA, Messenger / metabolism
  • Receptors, G-Protein-Coupled / physiology*


  • APLN protein, human
  • APLNR protein, human
  • Apelin
  • Apelin Receptors
  • Intercellular Signaling Peptides and Proteins
  • Ligands
  • RNA, Messenger
  • Receptors, G-Protein-Coupled