[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...

The aim of the present study was to investigate the effect of Apelin-13 on cardiomyocyte autophagy and to determine the underlying mechanism of this effect. To establish an autophagic model system, the cardiomyocytes of Sprague Dawley rats (postnatal day 3) were cultured and divided into five groups: normal control (Co), glucose deprivation (GD), GD+Apelin-13, GD+Apelin-13 treated with the Akt-...

Apelin is a potent inodilator with recently described antiatherogenic properties. We hypothesized that apelin might also attenuate abdominal aortic aneurysm (AAA) formation by limiting disease-related vascular wall inflammation. C57BL/6 mice implanted with osmotic pumps filled with apelin or saline were treated with pancreatic elastase to create infrarenal AAAs. Mice were euthanized for aortic ...

Apelin regulates various cell signaling processes through interaction with its specific cell-surface receptor, APJ, which is a member of a seven transmembrane G protein-coupled receptor superfamily. To develop a novel apelin analogue, we synthesized cyclic analogues of minimal apelin fragment RPRLSHKGPMPF (apelin-12), and evaluated their bioactivities in a recombinant human APJ-expressed cell l...

PURPOSE Apelin is a novel adipocytokine participating in diabetes, but its role in diabetic retinopathy (DR) is unknown. Our study aimed to investigate the effect of apelin on the proliferative potential in DR along with its antagonist inhibitory effects. PRINCIPAL FINDINGS Strong staining of apelin, co-localized with glial fibrillary acidic protein (GFAP) and vascular endothelial growth fact...

The role of the endogenous apelin system in pregnancy is not well understood. Apelin's actions in pregnancy are further complicated by the expression of multiple forms of the peptide. Using radioimmunoassay (RIA) alone, we established the expression of apelin content in the chorionic villi of preeclamptic (PRE) and normal pregnant women (NORM) at 36-38 wk of gestation. Total apelin content was ...

OBJECTIVE Apelin is an endogenous ligand for the G protein-coupled receptor, APJ, and participates in multiple physiological processes. To identify the roles of endogenous apelin, we investigated the phenotype of apelin-deficient (apelin-KO) mice. METHODS AND RESULTS Apelin-KO mice showed impaired retinal vascularization and ocular development, which were analyzed by histology, immunohistoche...

Apelin and its receptor APJ have pleiotropic effects in mice and humans and play a protective role in cardiovascular diseases at least partially by inhibiting oxidative stress. Our objective was to study the effect of apelin on the progression of kidney disease in mice with established type 1 diabetes. Ove26 mice with type 1 diabetes received daily subcutaneous injections of apelin for 2 or 14 ...

Vascular calcification, which results from a process osteoblastic differentiation of vascular smooth muscle cells (VSMCs), is a major risk factor for cardiovascular morbidity and mortality. Apelin is a recently discovered peptide that is the endogenous ligand for the orphan G-protein-coupled receptor, APJ. Several studies have identified the protective effects of apelin on the cardiovascular sy...

Apelin acts via the G protein-coupled apelin receptor (APJ) to mediate effects on cardiovascular and fluid homeostasis. G protein-coupled receptor (GPCR) trafficking has an important role in the regulation of receptor signalling pathways and cellular functions, however in the case of APJ the mechanisms and proteins involved in apelin-induced trafficking are not well understood. We generated a s...