Characteristics of patients with chronic kidney disease and Type 2 diabetes initiating finerenone in the USA: a multi-database, cross-sectional study.

Aim: Finerenone is safe and efficacious for treating patients with chronic kidney disease (CKD) and Type 2 diabetes (T2D). Evidence on the use of finerenone in clinical practice is lacking. Objective: To describe demographic and clinical characteristics of early adopters of finerenone in the United States, according to sodium-glucose cotransporter 2 inhibitor (SGLT2i) use and urine albumin-creatinine ratio (UACR) levels. Methods: Multi-database, observational, cross-sectional study, using data from two US databases (Optum Claims and Optum EHR). Three cohorts were included: finerenone initiators with prior CKD-T2D, finerenone initiators with prior CKD-T2D and concomitant SGLT2i use, finerenone initiators with prior CKD-T2D stratified according to UACR. Results: In total, 1015 patients were included, 353 from Optum Claims and 662 from Optum EHR. Mean age was 72.0 and 68.4 years in Optum claims and EHR, respectively. Median eGFR was 44 and 44 ml/min/1.73 m2; and median UACR was 132 (28-698)/365 (74-1185.4) mg/g, in Optum Claims and EHR, respectively. 70.5/70.4% were taking renin-angiotensin system inhibitors, 42.5/53.3% SGLT2i. Overall, 9.0/6.3% of patients had baseline UACR <30 mg/g, 15.0/20.2% had UACR 30-300 mg/g, and 14.4/27.6% had UACR >300 mg/g. Conclusion: Current management of patients with CKD-T2D reflects use of finerenone independently from background therapies and clinical characteristics, suggesting implementation of therapeutic strategies based on different modes of action.

Characteristics, treatment patterns, and residual cardiovascular risk of patients with a first acute myocardial infarction: A nationwide population-based cohort study in Norway.

There are few nationwide descriptive studies of longitudinal drug use and residual cardiovascular risk in patients with myocardial infarction (MI) in contemporary clinical practice. The objectives of this work were to describe characteristics and longitudinal cardiovascular drug use of patients with a first acute MI in Norway, and to quantify residual risks of cardiovascular events and death. Using nationwide health registries in Norway, we identified 43 750 adults with a first MI (2010 to 2015) and ≥1 prescription for antiplatelet medication. We described cardiovascular medication post-MI and calculated residual cardiovascular risks. Between 3 months and 13-15 months post MI, medication use dropped from 93.3% to 75.1% for low-dose aspirin, 78.1% to 11.0% for dual antiplatelet therapy, 91.6% to 78.7% for antihypertensives, and 88.0% to 70.7% for lipid-lowering therapy. Incidence rate ratios (IRRs) for recurrent MI were similar between subpopulations at 12 months and notably different at 12-36 months. IRRs (95% CIs) at 12-36 months were 1.52 (1.26-1.82) for 65-74 years, 2.26 (1.88-2.71) for 75-84 years, and 3.97 (3.29-4.79) for ≥85 years (vs. 18-49 years), 2.42 (2.18-2.69) for those with ischaemic heart disease (IHD), 2.26 (1.97-2.59) for peripheral artery disease (PAD), 2.17 (1.98-2.36) for hypertension, and 1.82 (1.65-2.01) for diabetes. In conclusion, secondary prevention medication use 13-15 months following a first MI is suboptimal among patients in Norway. The elderly and those with IHD, PAD, diabetes, or hypertension are at high-risk for recurrent MI/stroke/death and should be managed closely beyond the first year.

Proximal signaling responses in peripheral T cells from colorectal cancer patients are affected by high concentrations of circulating prostaglandin E2.

Patients with colorectal cancer (CRC) have been shown to have elevated levels of circulating prostaglandin E2 (PGE2) which promotes cancer progression and suppresses T cell immune responses. In this study we evaluated whether signaling responses in T lymphocytes obtained from peripheral blood of CRC patients were affected by the sustained exposure to increased levels of PGE2. The phosphorylation status of an extended panel of proteins involved in downstream signaling cascades in T cells was profiled at a single cell level both in naïve and antigen-experienced cells after triggering T cell-, prostaglandin- and interleukin-2 receptors. Peripheral T cells from patients with elevated PGE2 levels displayed aberrant T cell signaling responses downstream of the T cell receptor (assessed by reduced phosphorylation of CD3ζ and SLP76), and after triggering the IL-2 receptor (assessed by reduced phosphorylation of STAT5) when compared to T cells from CRC patients with lower levels of PGE2 and T cells from healthy blood donors. This signaling study of circulating T cells from CRC patients indicates that increased systemic PGE2 levels affect proximal T cell responses and confirms phospho-specific flow cytometry to be a valuable tool for revealing signaling signatures in immunological disorders.

Analysing phosphorylation-based signalling networks by phospho flow cytometry.

Analysis of signalling events by classical biochemical approaches is limited as the outcome is an averaged readout for protein activation of a single protein within a cell population. This is a clear restriction when addressing signalling events in mixed populations or subpopulations of cells. By combining flow cytometry with a panel of phosphospecific antibodies against several signal molecules simultaneously in a multi-parameter phospho flow cytometry analysis it is possible to obtain a higher level of understanding of the signal transduction dynamics at a single cell level. In addition, analysis of mixed cell populations makes it possible to study cells ex vivo in a state more closely resembling the in vivo situation. The multimeric analysis yields information on combinations of signals turned on and off in specific settings such as disease (signal nodes) that can be used for biomarker analysis and for development of drug screening strategies. Prostaglandin E(2) (PGE(2)) is known to signal through four G-protein coupled transmembrane receptors, EP1-4, activating a multitude of potential signalling pathways. The analysis of the PGE(2) signalling network elicited by activation of the four EP receptors in lymphoid cells revealing several signalling nodes is reviewed as an example.

High-resolution mapping of prostaglandin E2-dependent signaling networks identifies a constitutively active PKA signaling node in CD8+CD45RO+ T cells.

To analyze prostaglandin E(2) (PGE(2)) signaling in lymphoid cells, we introduce a multipronged strategy, combining temporal quantitative phosphoproteomics and phospho flow cytometry. We describe the PGE(2)-induced phosphoproteome by simultaneous monitoring of approximately 250 regulated phospho-epitopes, which, according to kinase prediction algorithms, originate from a limited number of kinase networks. Assessing these signaling pathways by phospho flow cytometry provided higher temporal resolution at various PGE(2) concentrations in multiple lymphoid cell subsets. This showed elevated levels of protein kinase A (PKA) signaling in unstimulated CD8(+)CD45RO(+) T cells, which correlated with suppressed proximal T-cell receptor signaling, indicating that PKA sets the threshold for activation. The combination of phosphoproteomics and high throughput phospho flow cytometry applied here provides a comprehensive generic framework for the analysis of signaling networks in mixed cell populations.

cGMP-independent inhibition of integrin alphaIIbbeta3-mediated platelet adhesion and outside-in signalling by nitric oxide.

We examined the influence of S-nitrosoglutathione (GSNO) on alpha(IIb)beta(3) integrin-mediated platelet adhesion to immobilised fibrinogen. GSNO induced a time- and concentration-dependent inhibition of platelet adhesion. Inhibition was cGMP-independent and associated with both reduced platelet spreading and protein tyrosine phosphorylation. To investigate the cGMP-independent effects of NO we evaluated integrin beta(3) phosphorylation. Adhesion to fibrinogen induced rapid phosphorylation of beta(3) on tyrosines 773 and 785, which was reduced by GSNO in a cGMP independent manner. Similar results were observed in suspended platelets indicating that NO-induced effects were independent of spreading-induced signalling. This is the first demonstration that NO directly regulates integrin beta(3) phosphorylation.

Inhibition of ADP-induced platelet adhesion to immobilised fibrinogen by nitric oxide: evidence for cGMP-independent mechanisms.

Nitric oxide (NO) is an established regulator of platelet function, although the processes by which NO modulates platelet adhesion are unclear. We studied the importance of Ca(2+) and phosphoinositol-3-kinase (PI3kinase) as targets for NO signalling, in the physiological context of platelet adhesion using adenosine diphosphate (ADP)-stimulated adhesion to immobilised fibrinogen. DPTA-NONOate induced a time and concentration-dependent inhibition of adhesion, and reduced protein tyrosine phosphorylation. The action of NO was cGMP-independent despite activation of the cGMP-signalling cascade, as evidenced by VASP phosphorylation. Furthermore, the cGMP-independent mechanism did not involve PKA. Platelet activation by ADP requires Ca(2+) and PI3kinase-dependent signalling pathways. We examined the effect of NO on these pathways using two approaches. Firstly, we dissected the signalling pathways using the P2Y(1)-receptor antagonist A3P5P, and secondly, directly inhibited Ca(2+) mobilisation and PI3kinase activity. ADP-induced adhesion was reduced but not abolished by A3P5P, suggesting signalling from P2Y(12) can induce adhesion. NO further reduced adhesion in the presence of A3P5P, indicating that NO inhibited adhesion independently of any effects on Ca(2+) mobilisation. Dimethyl bis-(o-aminophenoxy) ethane-tetraacetic acid (BAPTA) and wortmannin both partially inhibited ADP-induced adhesion, but completely abolished adhesion when used in combination, demonstrating that ADP-induced adhesion requires Ca(2+) and PI3kinase-regulated pathways. Combination of either dimethyl-BAPTA or wortmannin with DPTA-NONOate enhanced inhibition of both the Ca(2+) and PI3kinase-dependent pathways when compared to the levels of inhibition with either agent alone. Thus, we demonstrate that NO inhibits alpha(IIb)beta(3)-mediated adhesion, by targeting both Ca(2+) and PI3kinase pathways in a cGMP-independent manner.

Sodium orthovanadate induced tyrosine phosphorylation of platelet nitric oxide synthase negatively regulates enzyme activity.

The post-translational regulation of platelet nitric oxide synthase (NOS) activity is poorly understood. In the present study we examined how tyrosine phosphorylation of NOS, induced by the tyrosine phosphatase inhibitor sodium orthovanadate (VO4), influenced enzyme activity. Platelet NOS was basally tyrosine phosphorylated, but incubation with VO4 (100-1000 microM) led to a concentration-dependent increase in tyrosine phosphorylation of the enzyme with maximal effects observed at 500 microM. Importantly, we observed no change in serine(1179) or threonine(497) phosphorylation. The increased tyrosine phosphorylation was associated with reduced NOS activity and NO bioavailability, as evidenced by measurement of [(3)H]-L-citrulline and cGMP respectively. The signalling events underlying the effects of VO4 were studied using specific inhibitors to kinases that are known to influence NOS activity. Preincubation of platelets with the Src kinase inhibitor PP2 (20 microM) blocked VO4-induced tyrosine phosphorylation of NOS and abolished the effects of VO4 on cGMP formation. The PKC inhibitor Ro-31-8220 (10 microM) had no effect on VO4-induced tyrosine phosphorylation, but did have a modest but significant effect on cGMP formation. In contrast, the PI-3-kinase inhibitor wortmannin (100 nM) had no effect on either tyrosine phosphorylation or cGMP formation. Our data indicate that tyrosine phosphorylation may act to repress NOS activity. Furthermore, VO4 induces a Src-dependent, and to a lesser degree PKC-dependent, inhibition of platelet NOS.