BAY 41-2272, a soluble guanylate cyclase agonist, activates human mononuclear phagocytes

Pyrazole-containing pharmaceuticals: target, pharmacological activity, and their SAR studies

Pyrazole is a five-membered heterocycle bearing two adjacent nitrogen atoms. Both pharmaceutical agents and natural products with pyrazole as a nucleus have exhibited a broad spectrum of biological activities. In the last few decades, more than 40 pyrazole-containing drugs have been approved by the FDA for the treatment of a broad range of clinical conditions including celecoxib (anti-inflammatory), CDPPB (antipsychotic), difenamizole (analgesic), etc. Owing to the unique physicochemical properties of the pyrazole core, pyrazole-containing drugs may exert better pharmacokinetics and pharmacological effects compared with drugs containing similar heterocyclic rings. The purpose of this paper is to provide an overview of all the existing drugs bearing a pyrazole nucleus that have been approved or in clinical trials, involving their pharmacological activities and SAR studies.

Ambrisentan, an endothelin receptor type A-selective antagonist, inhibits cancer cell migration, invasion, and metastasis

Several studies reported a central role of the endothelin type A receptor (ETAR) in tumor progression leading to the formation of metastasis. Here, we investigated the in vitro and in vivo anti-tumor effects of the FDA-approved ETAR antagonist, Ambrisentan, which is currently used to treat patients with pulmonary arterial hypertension. In vitro, Ambrisentan inhibited both spontaneous and induced migration/invasion capacity of different tumor cells (COLO-357 metastatic pancreatic adenocarcinoma, OvCar3 ovarian carcinoma, MDA-MB-231 breast adenocarcinoma, and HL-60 promyelocytic leukemia). Whole transcriptome analysis using RNAseq indicated Ambrisentan's inhibitory effects on the whole transcriptome of resting and PAR2-activated COLO-357 cells, which tended to normalize to an unstimulated profile. Finally, in a pre-clinical murine model of metastatic breast cancer, treatment with Ambrisentan was effective in decreasing metastasis into the lungs and liver. Importantly, this was associated with a significant enhancement in animal survival. Taken together, our work suggests a new therapeutic application for Ambrisentan in the treatment of cancer metastasis.

Antihypertrophic Effects of Nebivolol on Neonatal Cardiomyocyte Hypertrophy Models

The antihypertrophic effect of nebivolol over cardioselective beta-blockers (β-blockers) is attributed to the activation of cardiac nitric oxide signaling. However, the precise role of nebivolol on hypertrophied cardiomyocytes remains unclear. In the current study, in vitro cardiomyocyte hypertrophy model was induced with isoprenaline (10 μM), angiotensin II (1 μM), and phenylephrine (20 μM) in neonatal cardiomyocytes isolated from 0- to 2-day-old Sprague-Dawley rats. In addition to hypertrophic agents, cardiomyocytes were treated with nebivolol (1 μM), metoprolol (10 μM), N(ω)-nitro-L-arginine methyl ester (L-NAME) (100 μM), KT5823 (1 μM), DETA-NONOate (1-10 μM), and BAY412272 (10 μM). After 24 hours of treatment, cardiomyocyte size and transcriptional changes in cardiac hypertrophy markers were evaluated. Cardiomyocyte size increased equally in response to all hypertrophic agents. Nebivolol reduced the enhancement in cell size in response to both isoprenaline and angiotensin II; metoprolol did not. The antihypertrophic effect of nebivolol was prevented with L-NAME blockage indicating the role of NOS signaling on cardiomyocyte hypertrophy. The increased mRNA levels of atrial natriuretic peptide induced by isoprenaline decreased with nebivolol, but both β-blockers reduced the angiotensin II-induced increase in atrial natriuretic peptide expression. Combined, these results reveal that by activating NOS signaling, nebivolol exerts antihypertrophic effects on neonatal cardiomyocytes independent from the action mechanism of hypertrophic stimulus.

BAY 41-2272 inhibits human T lymphocyte functions

BAY 41-2272 increases guanosine 3', 5'-cyclic monophosphate (cGMP) levels by stimulating soluble guanylate cyclase (sGC). In this study, we evaluated the effect of BAY 41-2272 on human T lymphocyte functions. Pretreating T cells for 24 h with BAY 41-2272 at 3 μM and 30 μM, followed by activation with 90 nM phorbol myristate acetate (PMA), inhibited interferon-gamma (IFN-γ) production, with 3 μM and 30 μM BAY causing 16.5-fold and 12.1-fold inhibition, respectively, compared to PMA alone (p < 0.05, one-way ANOVA followed by Tukey's test). We also observed suppressive effects on the expression of CD69, with 30 μM BAY causing 3.55-fold lower expression than PMA/ionomycin (p < 0.001 one-way ANOVA followed by Tukey's test), and T-bet, with 30 μM BAY causing 1.47-fold lower expression than PMA/ionomycin (p < 0.05, one-way ANOVA test followed by Tukey's test). Additionally, T lymphocyte proliferation was reduced 2.13-fold and 4.3-fold, respectively, by 3 μM BAY and 30 μM BAY compared to PMA/ionomycin (p < 0.01, p < 0.001, one-way ANOVA followed by Tukey's test). BAY 41-2272 inhibits human T lymphocyte function and may be explored as an immunomodulatory drug in patients with autoimmune/inflammatory diseases and lymphoproliferative syndromes.

BAY 41-2272 inhibits human neutrophil functions

BAY 41-2272 is a guanylyl cyclase (GC) stimulator derived from YC-1 (3-[(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole]). Previous studies by our group showed that BAY 41-2272 activates human monocytes via soluble guanylyl cyclase (sGC) and cGMP. In this study, we investigated the effect of BAY 41-2272 on human neutrophil function and found that 30 μM BAY 41-2272 inhibits neutrophil migration (1.82-fold lower than FMLP, P < 0.05 by one-way ANOVA followed by Tukey's test), oxidative burst (1.70-fold lower than PMA, P < 0.05 by one-way ANOVA followed by Tukey's test), and IL-8 cytokine production (1.80-fold lower than PMA, P < 0.05 by one-way ANOVA followed by Tukey's test). Our results suggest that these effects are independent of the sGC pathway but dependent instead on cGMP production, as the response induced by 30 μM BAY 41-2272 was 6.40-fold greater than that observed in our negative control (P < 0.05 by parametric t-test). 1H-[1, 2, 4] oxadiazolo [4,3-a] quinoxalin-1-one (ODQ), which is an irreversible inhibitor of sGC, was unable to reverse the effects of BAY 41-2272 on human neutrophils, indicating that this drug acts independently of sGC. Our results confirm the immunomodulatory effect of BAY 41-2272 on human neutrophils.

CD40 ligand deficiency causes functional defects of peripheral neutrophils that are improved by exogenous IFN-γ

BACKGROUND

Patients with X-linked hyper-IgM syndrome caused by CD40 ligand (CD40L) deficiency often present with episodic, cyclic, or chronic neutropenia, suggesting abnormal neutrophil development in the absence of CD40L-CD40 interaction. However, even when not neutropenic and despite immunoglobulin replacement therapy, CD40L-deficient patients are susceptible to life-threatening infections caused by opportunistic pathogens, suggesting impaired phagocyte function and the need for novel therapeutic approaches.

OBJECTIVES

We sought to analyze whether peripheral neutrophils from CD40L-deficient patients display functional defects and to explore the in vitro effects of recombinant human IFN-γ (rhIFN-γ) on neutrophil function.

METHODS

We investigated the microbicidal activity, respiratory burst, and transcriptome profile of neutrophils from CD40L-deficient patients. In addition, we evaluated whether the lack of CD40L in mice also affects neutrophil function.

RESULTS

Neutrophils from CD40L-deficient patients exhibited defective respiratory burst and microbicidal activity, which were improved in vitro by rhIFN-γ but not soluble CD40L. Moreover, neutrophils from patients showed reduced CD16 protein expression and a dysregulated transcriptome suggestive of impaired differentiation. Similar to CD40L-deficient patients, CD40L knockout mice were found to have impaired neutrophil responses. In parallel, we demonstrated that soluble CD40L induces the promyelocytic cell line HL-60 to proliferate and mature by regulating the expression of genes of the same Gene Ontology categories (eg, cell differentiation) when compared with those dysregulated in peripheral blood neutrophils from CD40L-deficient patients.

CONCLUSION

Our data suggest a nonredundant role of CD40L-CD40 interaction in neutrophil development and function that could be improved in vitro by rhIFN-γ, indicating a potential novel therapeutic application for this cytokine.

Soluble CD40L is associated with increased oxidative burst and neutrophil extracellular trap release in Behçet's disease

Background

Studies have suggested that soluble factors in plasma from patients with active (aBD) and inactive (iBD) Behçet’s disease (BD) stimulate neutrophil function. Soluble CD40 ligand (sCD40L) is an important mediator of inflammation in BD. Its expression and effect on neutrophil oxidative burst and neutrophil extracellular trap (NET) release have not been characterized. In this study, we sought to investigate the role of plasma and the CD40L pathway on NET release and the oxidative burst profile in patients with aBD and iBD.

Methods

Neutrophils and peripheral blood mononuclear cells (PBMCs) were obtained from patients with aBD (n = 30), patients with iBD (n = 31), and healthy control subjects (HCs; n = 30). sCD40L plasma concentration was determined in individual samples. A pool of plasma for each group was created. In some experiments, plasma pools were treated with recombinant CD40 (rhCD40-muIg) for sCD40L blockade. NET release and H₂O₂/O₂⁻ production were determined after stimulation with phorbol 12-myristate 13-acetate, sCD40L, or plasma pool. Flow cytometric analysis was performed to evaluate the expression of (1) CD40, Mac-1, and phosphorylated NF-κB p65 on neutrophils and monocytes and (2) CD40L on activated T cells and platelets. CD40L gene expression in PBMCs was determined by qRT-PCR.

Results

sCD40L plasma levels were significantly higher in patients with iBD (median 17,234, range 2346–19,279 pg/ml) and patients with aBD (median 18,289, range 413–19,883 pg/ml) than in HCs (median 47.5, range 33.7–26.7 pg/ml; p < 0.001). NET release was constitutively increased in BD compared with HC. NET release and H₂O₂/O₂⁻ were higher after stimulation with sCD40L or BD plasma and decreased after sCD40L blockade. Mac-1 expression was constitutively increased in neutrophils of patients with aBD (88.7 ± 13.2% of cells) and patients with iBD (89.2 ± 20.1% of cells) compared with HC (27.1 ± 18.8% of cells; p < 0.01). CD40 expression on phagocytes and CD40L expression on platelets were similar in the three groups. PBMCs as well as nonactivated and activated CD4⁺ T cells from patients with BD showed higher CD40L expression.

Conclusions

Plasma from patients with aBD exerts a stimulus on NET release and oxidative burst, probably induced by sCD40L.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1443-5) contains supplementary material, which is available to authorized users.

BAY 41-2272 activates host defence against local and disseminated Candida albicans infections

In our previous study, we have found that 5-cyclopropyl-2-[1-(2-fluoro-benzyl)-1H-pyrazolo[3,4-b]pyridine-3-yl]-pyrimidin-4-ylamine (BAY 41-2272), a guanylate cyclase agonist, activates human monocytes and the THP-1 cell line to produce the superoxide anion, increasing in vitro microbicidal activity, suggesting that this drug can be used to modulate immune functioning in primary immunodeficiency patients. In the present work, we investigated the potential of the in vivo administration of BAY 41-2272 for the treatment of Candida albicans and Staphylococcus aureus infections introduced via intraperitoneal and subcutaneous inoculation. We found that intraperitoneal treatment with BAY 41-2272 markedly increased macrophage-dependent cell influx to the peritoneum in addition to macrophage functions, such as spreading, zymosan particle phagocytosis and nitric oxide and phorbol myristate acetate-stimulated hydrogen peroxide production. Treatment with BAY 41-2272 was highly effective in reducing the death rate due to intraperitoneal inoculation of C. albicans, but not S. aureus. However, we found that in vitro stimulation of peritoneal macrophages with BAY 41-2272 markedly increased microbicidal activities against both pathogens. Our results show that the prevention of death by the treatment of C. albicans-infected mice with BAY 41-2272 might occur primarily by the modulation of the host immune response through macrophage activation.