7 research outputs found
A novel cyclic biased agonist of the apelin receptor, MM07, is disease modifying in the rat monocrotaline model of pulmonary arterial hypertension.
BACKGROUND AND PURPOSE: Apelin is an endogenous vasodilatory and inotropic peptide that is down-regulated in human pulmonary arterial hypertension, although the density of the apelin receptor is not significantly attenuated. We hypothesised that a G protein-biased apelin analogue MM07, which is more stable than the endogenous apelin peptide, may be beneficial in this condition with the advantage of reduced β-arrestin-mediated receptor internalisation with chronic use. EXPERIMENTAL APPROACH: Male Sprague-Dawley rats received either monocrotaline to induce pulmonary arterial hypertension or saline and then daily i.p. injections of either MM07 or saline for 21 days. The extent of disease was assessed by right ventricular catheterisation, cardiac MRI, and histological analysis of the pulmonary vasculature. The effect of MM07 on signalling, proliferation, and apoptosis of human pulmonary artery endothelial cells was investigated. KEY RESULTS: MM07 significantly reduced the elevation of right ventricular systolic pressure and hypertrophy induced by monocrotaline. Monocrotaline-induced changes in cardiac structure and function, including right ventricular end-systolic and end-diastolic volumes, ejection fraction, and left ventricular end-diastolic volume, were attenuated by MM07. MM07 also significantly reduced monocrotaline-induced muscularisation of small pulmonary blood vessels. MM07 stimulated endothelial NOS phosphorylation and expression, promoted proliferation, and attenuated apoptosis of human pulmonary arterial endothelial cells in vitro. CONCLUSION AND IMPLICATIONS: Our findings suggest that chronic treatment with MM07 is beneficial in this animal model of pulmonary arterial hypertension by addressing disease aetiology. These data support the development of G protein-biased apelin receptor agonists with improved pharmacokinetic profiles for use in human disease.the Medical Research Council MC_PC_14116 [to APD] Wellcome Trust [107715/Z/15/Z to APD], Programme in Metabolic and Cardiovascular Disease [096822/Z/11/Z to PY; 203814/Z/16/A to TLW], Parke Davis Fellowship [to PY], British Heart Foundation [FS/14/59/31282 to CR] and in part by the National Institute for Health Research Cambridge Biomedical Research Centre
Adenosine signaling mediates hypoxic responses in the chronic lymphocytic leukemia microenvironment
The chronic lymphocytic leukemia (CLL) niche is a closed environment where leukemic cells derive growth and survival signals through their interaction with macrophages and T lymphocytes. Here, we show that the CLL lymph node niche is characterized by overexpression and activation of HIF-1a, which increases adenosine generation and signaling, affecting tumor and host cellular responses. Hypoxia in CLL lymphocytes modifies central metabolic pathways, protects against drug-driven apoptosis, and induces interleukin 10 (IL-10) production. In myeloid cells, it forces monocyte differentiation to macrophages expressing IRF4, IDO, CD163, and CD206, hallmarks of the M2 phenotype, which promotes tumor progression. It also induces IL-6 production and enhances nurturing properties. Low oxygen levels decrease T-cell proliferation, promote glycolysis, and cause the appearance of a population of PD-11 and IL-10–secreting T cells. Blockade of the A2A adenosine receptor counteracts these effects on all cell populations, making leukemic cells more susceptible to pharmacological agents while restoring immune competence and T-cell proliferation. Together, these results indicate that adenosine signaling through the A2A receptor mediates part of the effects of hypoxia. They also suggest that therapeutic strategies to inhibit the adenosinergic axis may be useful adjuncts to chemotherapy or tyrosine kinase inhibitors in the treatment of CLL patients
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Footprints: Jewish Books through Time and Place--Code Repository 2022.07.01
Source code for the Footprints database. Footprints is a project to develop a database that tracks individual books through time and space to uncover patterns of trade and learning throughout the Jewish communities of Europe, Asia and the Americas during the modern period
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Footprints: Jewish Books through Time and Place--Code Repository v1.0
Source code for the Footprints database. Footprints is a project to develop a database that tracks individual books through time and space to uncover patterns of trade and learning throughout the Jewish communities of Europe, Asia and the Americas during the modern period
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Footprints: Jewish Books through Time and Place--Code Repository 2021.10.01
Source code for the Footprints database. Footprints is a project to develop a database that tracks individual books through time and space to uncover patterns of trade and learning throughout the Jewish communities of Europe, Asia and the Americas during the modern period
Recommended from our members
Footprints: Jewish Books through Time and Place--Code Repository 2024.01.31
Source code for the Footprints database. Footprints is a project to develop a database that tracks individual books through time and space to uncover patterns of trade and learning throughout the Jewish communities of Europe, Asia and the Americas during the modern period