Loss of soluble guanylyl cyclase in platelets contributes to atherosclerotic plaque formation and vascular inflammation.

Variants in genes encoding the soluble guanylyl cyclase (sGC) in platelets are associated with coronary artery disease (CAD) risk. Here, by using histology, flow cytometry and intravital microscopy, we show that functional loss of sGC in platelets of atherosclerosis-prone mice contributes to atherosclerotic plaque formation, particularly via increasing in vivo leukocyte adhesion to atherosclerotic lesions. In vitro experiments revealed that supernatant from activated platelets lacking sGC promotes leukocyte adhesion to endothelial cells (ECs) by activating ECs.

Identification and characterization of the new generation soluble guanylate cyclase stimulator BAY-747 designed for the treatment of resistant hypertension.

Background And Purpose: First-generation soluble guanylate cyclase (sGC) stimulators have shown clinical benefit in pulmonary hypertension (riociguat) and chronic heart failure (vericiguat). However, given the broad therapeutic opportunities for sGC stimulators, tailored molecules for distinct indications are required.

Experimental Approach: We report the high-throughput screening (HTS)-based discovery of a second generation of sGC stimulators from a novel imidazo[1,2-a]pyridine lead series.

BAY-6096: A Potent, Selective, and Highly Water-Soluble Adrenergic α Antagonist.

After acute myocardial infarction, early reperfusion is the most effective strategy for reducing cardiac damage and improving clinical outcome. However, restoring blood flow to the ischemic myocardium can paradoxically induce injury by itself (reperfusion injury), with microvascular dysfunction being one contributing factor. α adrenergic receptors have been hypothesized to be involved in this process.

BAY-7081: A Potent, Selective, and Orally Bioavailable Cyanopyridone-Based PDE9A Inhibitor.

Despite advances in the treatment of heart failure in recent years, options for patients are still limited and the disease is associated with considerable morbidity and mortality. Modulating cyclic guanosine monophosphate levels within the natriuretic peptide signaling pathway by inhibiting PDE9A has been associated with beneficial effects in preclinical heart failure models. We herein report the identification of BAY-7081, a potent, selective, and orally bioavailable PDE9A inhibitor with very good aqueous solubility starting from a high-throughput screening hit.

Inhaled mosliciguat (BAY 1237592): targeting pulmonary vasculature via activating apo-sGC.

Background: Oxidative stress associated with severe cardiopulmonary diseases leads to impairment in the nitric oxide/soluble guanylate cyclase signaling pathway, shifting native soluble guanylate cyclase toward heme-free apo-soluble guanylate cyclase. Here we describe a new inhaled soluble guanylate cyclase activator to target apo-soluble guanylate cyclase and outline its therapeutic potential.

Methods: We aimed to generate a novel soluble guanylate cyclase activator, specifically designed for local inhaled application in the lung.

Establishment of a novel, cell-based autotaxin assay.

Autotaxin (ATX) plays an important role in (patho-)physiological lysophosphatidic acid (LPA) signaling. Here we describe the establishment of novel cell-based ATX assay formats. ATX-mediated LPA generation is detected by using a stable LPA receptor reporter cell line.

Discovery of the Soluble Guanylate Cyclase Activator Runcaciguat (BAY 1101042).

Herein we describe the discovery, mode of action, and preclinical characterization of the soluble guanylate cyclase (sGC) activator runcaciguat. The sGC enzyme, via the formation of cyclic guanosine monophoshphate, is a key regulator of body and tissue homeostasis. sGC activators with their unique mode of action are activating the oxidized and heme-free and therefore NO-unresponsive form of sGC, which is formed under oxidative stress.

Development of a novel, sensitive cell-based corin assay.

Corin (atrial natriuretic peptide-converting enzyme, EC 3.4.21) is a transmembrane serine protease expressed in cardiomyocytes.

PDE2 at the crossway between cAMP and cGMP signalling in the heart.

The cyclic nucleotides cAMP and cGMP are central second messengers in cardiac cells and critical regulators of cardiac physiology as well as pathophysiology. Consequently, subcellular compartmentalization allows for spatiotemporal control of cAMP/cGMP metabolism and subsequent regulation of their respective effector kinases PKA or PKG is most important for cardiac function in health and disease. While acute cAMP-mediated signalling is a mandatory prerequisite for the physiological fight-or-flight response, sustained activation of this pathway may lead to the progression of heart failure.

Discovery of the Soluble Guanylate Cyclase Stimulator Vericiguat (BAY 1021189) for the Treatment of Chronic Heart Failure.

The first-in-class soluble guanylate cyclase (sGC) stimulator riociguat was recently introduced as a novel treatment option for pulmonary hypertension. Despite its outstanding pharmacological profile, application of riociguat in other cardiovascular indications is limited by its short half-life, necessitating a three times daily dosing regimen. In our efforts to further optimize the compound class, we have uncovered interesting structure-activity relationships and were able to decrease oxidative metabolism significantly.

Phosphodiesterase 2 Protects Against Catecholamine-Induced Arrhythmia and Preserves Contractile Function After Myocardial Infarction.

Rationale: Phosphodiesterase 2 is a dual substrate esterase, which has the unique property to be stimulated by cGMP, but primarily hydrolyzes cAMP. Myocardial phosphodiesterase 2 is upregulated in human heart failure, but its role in the heart is unknown.

Objective: To explore the role of phosphodiesterase 2 in cardiac function, propensity to arrhythmia, and myocardial infarction.

Development of Potent and Metabolically Stable APJ Ligands with High Therapeutic Potential.

The apelin ligand receptor system is an important target to develop treatment strategies for cardiovascular diseases. Although apelin exhibits strong inotropic effects, its pharmaceutical application is limited because no agonist with suitable properties is available. On the one hand, peptide ligands are too instable, and on the other hand, small-molecule agonists show only low potency.

Luteinizing Hormone Causes Phosphorylation and Activation of the cGMP Phosphodiesterase PDE5 in Rat Ovarian Follicles, Contributing, Together with PDE1 Activity, to the Resumption of Meiosis.

The meiotic cell cycle of mammalian oocytes in preovulatory follicles is held in prophase arrest by diffusion of cGMP from the surrounding granulosa cells into the oocyte. Luteinizing hormone (LH) then releases meiotic arrest by lowering cGMP in the granulosa cells. The LH-induced reduction of cGMP is caused in part by a decrease in guanylyl cyclase activity, but the observation that the cGMP phosphodiesterase PDE5 is phosphorylated during LH signaling suggests that an increase in PDE5 activity could also contribute.

Dephosphorylation and inactivation of NPR2 guanylyl cyclase in granulosa cells contributes to the LH-induced decrease in cGMP that causes resumption of meiosis in rat oocytes.

In mammals, the meiotic cell cycle of oocytes starts during embryogenesis and then pauses. Much later, in preparation for fertilization, oocytes within preovulatory follicles resume meiosis in response to luteinizing hormone (LH). Before LH stimulation, the arrest is maintained by diffusion of cyclic (c)GMP into the oocyte from the surrounding granulosa cells, where it is produced by the guanylyl cyclase natriuretic peptide receptor 2 (NPR2).

Engineering of a red-light-activated human cAMP/cGMP-specific phosphodiesterase.

Sensory photoreceptors elicit vital physiological adaptations in response to incident light. As light-regulated actuators, photoreceptors underpin optogenetics, which denotes the noninvasive, reversible, and spatiotemporally precise perturbation by light of living cells and organisms. Of particular versatility, naturally occurring photoactivated adenylate cyclases promote the synthesis of the second messenger cAMP under blue light.

Characterization of the cellular activity of PDE 4 inhibitors using two novel PDE 4 reporter cell lines.

We report here the generation and pharmacological characterization of two novel PDE 4B1 and PDE 4D3 reporter cell lines. Intracellular cAMP levels are monitored in these cells by a cAMP-sensitive biosensor. We used the recombinant PDE 4B1 and PDE 4D3 reporter cell lines to characterize the cellular effects of various competitive and allosteric PDE 4 inhibitors.

Dynamics of Gαi1 interaction with type 5 adenylate cyclase reveal the molecular basis for high sensitivity of Gi-mediated inhibition of cAMP production.

Many physiological and pathophysiological processes are regulated by cAMP. Different therapies directly or indirectly influence the cellular concentration of this second messenger. A wide variety of receptors either activates or inhibits adenylate cyclases in order to induce proper physiological responses.

Pharmacological characterization of receptor guanylyl cyclase reporter cell lines.

Receptor guanylyl cyclases are implicated in a growing number of pathophysiologies and, therefore, represent an important target class for drug development. We report here the generation and pharmacological characterization of three particulate guanylyl cyclase (pGC) reporter cell lines. Plasmid constructs encoding the natriuretic peptide receptors GC-A and GC-B, and the heat-stable enterotoxin receptor GC-C, were stably transfected in a parental reporter cell line expressing a cyclic nucleotide-gated (CNG) cation channel, acting as the biosensor for intracellular cGMP.

Luteinizing hormone reduces the activity of the NPR2 guanylyl cyclase in mouse ovarian follicles, contributing to the cyclic GMP decrease that promotes resumption of meiosis in oocytes.

In preovulatory ovarian follicles of mice, meiotic prophase arrest in the oocyte is maintained by cyclic GMP from the surrounding granulosa cells that diffuses into the oocyte through gap junctions. The cGMP is synthesized in the granulosa cells by the transmembrane guanylyl cyclase natriuretic peptide receptor 2 (NPR2) in response to the agonist C-type natriuretic peptide (CNP). In response to luteinizing hormone (LH), cGMP in the granulosa cells decreases, and as a consequence, oocyte cGMP decreases and meiosis resumes.

Chemosensory Ca2+ dynamics correlate with diverse behavioral phenotypes in human sperm.

In the female reproductive tract, mammalian sperm undergo a regulated sequence of prefusion changes that "prime" sperm for fertilization. Among the least understood of these complex processes are the molecular mechanisms that underlie sperm guidance by environmental chemical cues. A "hard-wired" Ca(2+) signaling strategy that orchestrates specific motility patterns according to given functional requirements is an emerging concept for regulation of sperm swimming behavior.

A multidimensional strategy to detect polypharmacological targets in the absence of structural and sequence homology.

Conventional drug design embraces the "one gene, one drug, one disease" philosophy. Polypharmacology, which focuses on multi-target drugs, has emerged as a new paradigm in drug discovery. The rational design of drugs that act via polypharmacological mechanisms can produce compounds that exhibit increased therapeutic potency and against which resistance is less likely to develop.

Atrial natriuretic peptide and nitric oxide signaling antagonizes vasopressin-mediated water permeability in inner medullary collecting duct cells.

AVP and atrial natriuretic peptide (ANP) have opposite effects in the kidney. AVP induces antidiuresis by insertion of aquaporin-2 (AQP2) water channels into the plasma membrane of collecting duct principal cells. ANP acts as a diuretic factor.

Discovery of riociguat (BAY 63-2521): a potent, oral stimulator of soluble guanylate cyclase for the treatment of pulmonary hypertension.

Soluble guanylate cyclase (sGC) is a key signal-transduction enzyme activated by nitric oxide (NO). Impairments of the NO-sGC signaling pathway have been implicated in the pathogenesis of cardiovascular and other diseases. Direct stimulation of sGC represents a promising therapeutic strategy particularly for the treatment of pulmonary hypertension (PH), a disabling disease associated with a poor prognosis.

A novel PDE2A reporter cell line: characterization of the cellular activity of PDE inhibitors.

We report here the generation and pharmacological characterization of a phosphodiesterase 2A (PDE2A) reporter cell line. Human PDE2A was stably transfected in a parental cell line expressing the atrial natriuretic peptide (ANP) receptor and the cyclic nucleotide-gated (CNG) cation channel CNGA2, acting as the biosensor for intracellular cGMP. In this reporter cell line, cGMP levels can be monitored in real-time via aequorin luminescence stimulated by calcium influx through the CNG channel.