Apelin is a bioactive peptide involved in the control of energy metabolism. In the hypothalamus, chronic exposure to high levels of apelin is associated with an increase in hepatic glucose production, and then contributes to the onset of type 2 diabetes. However, the molecular mechanisms behind deleterious effects of chronic apelin in the brain and consequences on energy expenditure and thermog...

Angiotensin-converting enzyme 2 (ACE2)/Ang II/Ang 1-7 and the apelin/APJ are two important peptide systems which exert diverse effects on the cardiovascular system. ACE2 is a key negative regulator of the renin-angiotensin system (RAS) where it metabolizes angiotensin (Ang) II into Ang 1-7, an endogenous antagonist of Ang II. Both the prolonged activation of RAS and the loss of ACE2 can be detr...

BACKGROUND The aim of this study was to determine the relevance of apelin and insulin resistance (IR) with polycystic ovary syndrome (PCOS) and to assess the possible therapeutic effect of the combined therapy of drospirenone-ethinylestradiol (DRSP-EE) combined with metformin. MATERIAL AND METHODS Sixty-three PCOS patients and 40 non-PCOS infertile patients were recruited. The fasting serum l...

Whereas the role of the G-protein-coupled APJ receptor and its ligand, apelin, in angiogenesis has been well documented, the ability of the apelin/APJ system to induce lymphangiogenesis and lymphatic metastasis has been largely unexplored. To this end, we first show that APJ is expressed in lymphatic endothelial cells (LECs) and, moreover, that it responds to apelin by activating the apelinergi...

OBJECTIVE The endothelial response elicited by the G-protein-coupled receptor pathway involving apelin and APJ predicts an overall vasoprotective effect. As a number of downstream endothelial targets of apelin/APJ signaling are also known to be targeted by statins (3-hydroxy-3-methyl-glutaryl [HMG]-CoA reductase inhibitors) as potential mediators of their known pleiotropic effects, we evaluated...

Progression of ischemic retinal diseases, such as diabetic retinopathy, is closely associated with pathological retinal angiogenesis mainly induced by vascular endothelial growth factor (VEGF). Anti-angiogenic therapy using anti-VEGF antibodies is effective in treating diabetic retinopathy, even though its efficacy is not long-lasting. Since many factors are involved in angiogenesis, it is reas...

AIM The apelin-APJ system regulates angiogenesis, and is overexpressed in several types of cancer. The aim of this study was to clarify the role of the apelin-APJ system in the angiogenesis of hepatocellular carcinoma (HCC). MATERIALS AND METHODS Expressions of angiogenic factors and vascular markers were investigated in specimens from 90 HCC patients. A subcutaneous HCC tumor mouse model was...

BACKGROUND Apelin is a selective endogenous ligand of the APJ receptor, which genetically has closest identity to the angiotensin II type 1 receptor (AT-1). The effects of the apelin/APJ system on renal fibrosis still remain unclear. METHODS We examined the effects of the apelin/APJ system on renal fibrosis during AT-1 blockade in a mouse unilateral ureteral obstruction (UUO) model. RESULTS...

[Pyr(1)]apelin-13 is an endogenous vasodilator and inotrope but is downregulated in pulmonary hypertension and heart failure, making the apelin receptor an attractive therapeutic target. Agonists acting at the same G-protein-coupled receptor can be engineered to stabilize different conformational states and function as biased ligands, selectively stimulating either G-protein or β-arrestin pathw...

BACKGROUND AND PURPOSE Mitochondria-derived oxidative stress is believed to be crucially involved in cardiac ischaemia reperfusion (I/R) injury, although currently no therapies exist that specifically target mitochondrial reactive oxygen species (ROS) production. The present study was designed to evaluate the potential effects of the structural analogues of apelin-12, an adipocyte-derived pepti...