P2Y, P2Y and P2Y receptors: From the early days of cloning to their function.

The family of P2Y nucleotide receptors is composed of eight members differentiated by their pharmacology and their coupling to specific G-proteins and transduction mechanisms. The laboratory studying these nucleotide receptors at IRIBHM institute (Free University of Brussels) has participated actively in their cloning. We used classical cloning by homology strategies relying on polymerase chain reactions with degenerate primers or on DNA libraries screening with P2Y receptors-related primers or probes, respectively.

Disruption of the Microglial ADP Receptor P2Y Enhances Adult Hippocampal Neurogenesis.

In mammalian species, including humans, the hippocampal dentate gyrus (DG) is a primary region of adult neurogenesis. Aberrant adult hippocampal neurogenesis is associated with neurological pathologies. Understanding the cellular mechanisms controlling adult hippocampal neurogenesis is expected to open new therapeutic strategies for mental disorders.

P2Y Receptor Activation Promotes Inflammation and Tissue Remodeling in Pulmonary Fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a disease with a poor prognosis and very few available treatment options. The involvement of the purinergic receptor subtypes P2Y and P2X in fibrotic lung disease has been demonstrated recently. In this study, we investigated the role of P2Y receptors in the pathogenesis of IPF in humans and in the animal model of bleomycin-induced lung injury.

The purinergic receptor subtype P2Y2 mediates chemotaxis of neutrophils and fibroblasts in fibrotic lung disease.

Idiopathic pulmonary fibrosis (IPF) is a devastating disease with few available treatment options. Recently, the involvement of purinergic receptor subtypes in the pathogenesis of different lung diseases has been demonstrated. Here we investigated the role of the purinergic receptor subtype P2Y2 in the context of fibrotic lung diseases.

Mouse P2Y Nucleotide Receptor Is a Negative Regulator of Cardiac Adipose-Derived Stem Cell Differentiation and Cardiac Fat Formation.

Cardiac adipose tissue-derived stem cells (cASCs) have the ability to differentiate into multiple cell lineages giving them a high potential for use in regenerative medicine. Cardiac fat tissue still raises many unsolved questions related to its formation and features. P2Y nucleotide receptors have already been described as regulators of differentiation of bone-marrow derived stem cells, but remain poorly investigated in cASCs.

Central Role of P2Y6 UDP Receptor in Arteriolar Myogenic Tone.

Objective: Myogenic tone (MT) of resistance arteries ensures autoregulation of blood flow in organs and relies on the intrinsic property of smooth muscle to contract in response to stretch. Nucleotides released by mechanical strain on cells are responsible for pleiotropic vascular effects, including vasoconstriction. Here, we evaluated the contribution of extracellular nucleotides to MT.

Loss of Mouse P2Y6 Nucleotide Receptor Is Associated with Physiological Macrocardia and Amplified Pathological Cardiac Hypertrophy.

The study of the mechanisms leading to cardiac hypertrophy is essential to better understand cardiac development and regeneration. Pathological conditions such as ischemia or pressure overload can induce a release of extracellular nucleotides within the heart. We recently investigated the potential role of nucleotide P2Y receptors in cardiac development.

New insights on pyrimidine signalling within the arterial vasculature - Different roles for P2Y2 and P2Y6 receptors in large and small coronary arteries of the mouse.

Extracellular pyrimidines activate P2Y receptors on both smooth muscle cells and endothelial cells, leading to vasoconstriction and relaxation respectively. The aim of this study was to utilize P2Y knock-out (KO) mice to determine which P2Y receptor subtype are responsible for the contraction and relaxation in the coronary circulation and to establish whether P2Y receptors have different functions along the mouse coronary vascular tree. We tested stable pyrimidine analogues on isolated coronary arteries from P2Y2 and P2Y6 receptor KO mice in a myograph setup.

Purinergic P2Y6 receptors heterodimerize with angiotensin AT1 receptors to promote angiotensin II-induced hypertension.

The angiotensin (Ang) type 1 receptor (AT1R) promotes functional and structural integrity of the arterial wall to contribute to vascular homeostasis, but this receptor also promotes hypertension. In our investigation of how Ang II signals are converted by the AT1R from physiological to pathological outputs, we found that the purinergic P2Y6 receptor (P2Y6R), an inflammation-inducible G protein (heterotrimeric guanine nucleotide-binding protein)-coupled receptor (GPCR), promoted Ang II-induced hypertension in mice. In mice, deletion of P2Y6R attenuated Ang II-induced increase in blood pressure, vascular remodeling, oxidative stress, and endothelial dysfunction.

Increased atherosclerosis in P2Y13/apolipoprotein E double-knockout mice: contribution of P2Y13 to reverse cholesterol transport.

Aims: High-density lipoproteins (HDLs) protect against atherosclerosis mainly due to their function in hepatobiliary reverse cholesterol transport (RCT). This is a process whereby excess cholesterol from peripheral tissues is transported by HDL particles to the liver for further metabolism and biliary excretion. Hepatic uptake of HDL holoparticles involves the P2Y13 receptor, independently of the selective cholesteryl ester uptake mediated by scavenger receptor class B, type I (SR-BI).

P2Y2R deficiency attenuates experimental autoimmune uveitis development.

We aimed to study the role of the nucleotide receptor P2Y2R in the development of experimental autoimmune uveitis (EAU). EAU was induced in P2Y2+/+ and P2Y2-/- mice by immunization with IRBP peptide or by adoptive transfer of in vitro restimulated semi-purified IRBP-specific enriched T lymphocytes from spleens and lymph nodes isolated from native C57Bl/6 or P2Y2+/+ and P2Y2-/- immunized mice. Clinical and histological scores were used to grade disease severity.

Loss of mouse P2Y4 nucleotide receptor protects against myocardial infarction through endothelin-1 downregulation.

Nucleotides are released in the heart under pathological conditions, but little is known about their contribution to cardiac inflammation. The present study defines the P2Y4 nucleotide receptor, expressed on cardiac microvascular endothelial cells and involved in postnatal heart development, as an important regulator of the inflammatory response to cardiac ischemia. P2Y4-null mice displayed smaller infarcts in the left descending artery ligation model, as well as reduced neutrophil infiltration and fibrosis.

Enhancement of glucose uptake in mouse skeletal muscle cells and adipocytes by P2Y6 receptor agonists.

Glucose uptake by peripheral tissues such as skeletal muscles and adipocytes is important in the maintenance of glucose homeostasis. We previously demonstrated that P2Y6 receptor (P2Y6R) agonists protect pancreatic islet cells from apoptosis and stimulate glucose-dependent insulin release. Here, we investigated the effects of P2Y6R activation on glucose uptake in insulin target tissues.

Purinergic signalling and immune cells.

This review article provides a historical perspective on the role of purinergic signalling in the regulation of various subsets of immune cells from early discoveries to current understanding. It is now recognised that adenosine 5'-triphosphate (ATP) and other nucleotides are released from cells following stress or injury. They can act on virtually all subsets of immune cells through a spectrum of P2X ligand-gated ion channels and G protein-coupled P2Y receptors.

The enteric nervous system of P2Y13 receptor null mice is resistant against high-fat-diet- and palmitic-acid-induced neuronal loss.

Gastrointestinal symptoms have a major impact on the quality of life and are becoming more prevalent in the western population. The enteric nervous system (ENS) is pivotal in regulating gastrointestinal functions. Purinergic neurotransmission conveys a range of short and long-term cellular effects.

The P2Y13 receptor regulates phosphate metabolism and FGF-23 secretion with effects on skeletal development.

Purinergic signaling mediates many cellular processes, including embryonic development and regulation of endocrine signaling. The ADP P2Y13 receptor is known to regulate bone and stem cells activities, although relatively little is known about its role in bone development. In this study we demonstrate, using contemporary techniques, that deletion of the P2Y13 receptor results in an age-dependent skeletal phenotype that is governed by changes in phosphate metabolism and hormone levels.

Lack of P2Y13 in mice fed a high cholesterol diet results in decreased hepatic cholesterol content, biliary lipid secretion and reverse cholesterol transport.

Background: The protective effect of HDL is mostly attributed to their metabolic function in reverse cholesterol transport (RCT), a process whereby excess cellular cholesterol is taken up from peripheral cells, processed in HDL particles, and later delivered to the liver for further metabolism and biliary secretion. Mechanistically, the purinergic P2Y13 ADP-receptor is involved in hepatic HDL endocytosis (i.e.

A European approach to clinical investigator training.

A better education and training of clinical investigators and their teams is one of the factors that could foster the development of clinical research in Europe, a key objective of the Innovative Medicines Initiative (IMI). PharmaTrain (an IMI programme on training in medicines development), and European Clinical Research Infrastructures Network (ECRIN) have joined forces to address this issue. An advisory group composed of representatives of universities, pharmaceutical companies and other organisations met four times between June 2011 and July 2012.

Role of the P2Y13 receptor in the differentiation of bone marrow stromal cells into osteoblasts and adipocytes.

Accumulating evidence indicates that extracellular nucleotides, signaling through purinergic receptors, play a significant role in bone remodeling. Mesenchymal stem cells (MSCs) express functional P2Y receptors whose expression level is regulated during osteoblast or adipocyte differentiation. P2Y13 -deficient mice were previously shown to exhibit a decreased bone turnover associated with a reduction in the number of both osteoblasts and osteoclasts on the bone surfaces.

Contrast ultrasound for the quantification of deep vein thrombosis in living mice: effects of enoxaparin and P2Y12 receptor inhibition.

Background/objectives: We examined the applicability of contrast-enhanced ultrasound (CEUS) for imaging of murine deep vein thrombosis (DVT) and measured the effects of enoxaparin, ticagrelor and P2Y(12) receptor deficiency in vivo.

Methods: Deep vein thrombosis was induced by exposure to ferric chloride or ligation of the infrarenal vena cava of C57BL/6 mice after pretreatment with enoxaparin, ticagrelor or vehicle and in P2Y(12-/-) mice. Initial thrombus growth was visualized by intravital microscopy.

The P2Y13 receptor regulates extracellular ATP metabolism and the osteogenic response to mechanical loading.

ATP release and subsequent activation of purinergic receptors has been suggested to be one of the key transduction pathways activated by mechanical stimulation of bone. The P2Y(13) receptor, recently found to be expressed by osteoblasts, has been suggested to provide a negative feedback pathway for ATP release in different cell types. Therefore, we hypothesized that the P2Y(13) receptor may contribute to the mediation of osteogenic responses to mechanical stimulation by regulating ATP metabolism by osteoblasts.

Protective role of P2Y2 receptor against lung infection induced by pneumonia virus of mice.

ATP released in the early inflammatory processes acts as a danger signal by binding to purinergic receptors expressed on immune cells. A major contribution of the P2Y(2) receptor of ATP/UTP to dendritic cell function and Th2 lymphocyte recruitment during asthmatic airway inflammation was previously reported. We investigated here the involvement of P2Y(2) receptor in lung inflammation initiated by pneumonia virus of mice infection.

Purinergic P2Y₂ receptors promote neutrophil infiltration and hepatocyte death in mice with acute liver injury.

Background & Aims: During progression of liver disease, inflammation affects survival of hepatocytes. Endogenous release of adenosine triphosphate (ATP) in the liver activates purinergic P2 receptors (P2R), which regulate inflammatory responses, but little is known about the roles of these processes in the development of acute hepatitis.

Methods: We induced acute hepatitis in C57BL/6 mice by intravenous injection of concanavalin A and then analyzed liver concentrations of ATP and expression of P2R.

Gene deletion of P2Y4 receptor lowers exercise capacity and reduces myocardial hypertrophy with swimming exercise.

Nucleotides released within the heart under pathological conditions can be involved in cardioprotection or cardiac fibrosis through the activation purinergic P2Y(2) and P2Y(6) receptors, respectively. We previously demonstrated that adult P2Y(4)-null mice display a microcardia phenotype related to a cardiac angiogenic defect. To evaluate the functional consequences of this defect, we performed here a combination of cardiac monitoring and exercise tests.