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Aims: Heart failure with reduced ejection fraction (HFrEF) is a leading cause of death worldwide; thus, therapeutic improvements are needed. In vivo preclinical models are essential to identify molecular drug targets for future therapies. Transverse aortic constriction (TAC) is a well-established model of HFrEF; however, highly experienced personnel are needed for the surgery, and several weeks of follow-up are necessary to develop HFrEF. To this end, we aimed (i) to develop an easy-to-perform mouse model of HFrEF by treating Balb/c mice with angiotensin-II (Ang-II) for 2 weeks by minipump and (ii) to compare its cardiac phenotype and transcriptome to the well-established TAC model of HFrEF in C57BL/6J mice., Methods: Mortality and gross pathological data, cardiac structural and functional characteristics assessed by echocardiography and immunohistochemistry and differential gene expression obtained by RNA-sequencing and gene-ontology analyses were used to characterize and compare the two models. To achieve statistical comparability between the two models, changes in treatment groups related to the corresponding control were compared (ΔTAC vs. ΔAng-II)., Results: Compared with the well-established TAC model, chronic Ang-II treatment of Balb/c mice shares similarities in cardiac systolic functional decline (left ventricular ejection fraction: -57.25 ± 7.17% vs. -43.68 ± 5.31% in ΔTAC vs. ΔAng-II; P = 0.1794) but shows a lesser degree of left ventricular dilation (left ventricular end-systolic volume: 190.81 ± 44.13 vs. 57.37 ± 10.18 mL in ΔTAC vs. ΔAng-II; P = 0.0252) and hypertrophy (cell surface area: 58.44 ± 6.1 vs. 10.24 ± 2.87 μm 2 in ΔTAC vs. ΔAng-II; P < 0.001); nevertheless, transcriptomic changes in the two HFrEF models show strong correlation (Spearman's r = 0.727; P < 0.001). In return, Ang-II treatment in Balb/c mice needs significantly less procedural time [38 min, interquartile range (IQR): 31-46 min in TAC vs. 6 min, IQR: 6-7 min in Ang-II; P < 0.001] and surgical expertise, is less of an object for peri-procedural mortality (15.8% in TAC vs. 0% in Ang-II; P = 0.105) and needs significantly shorter follow-up for developing HFrEF., Conclusions: Here, we demonstrate for the first time that chronic Ang-II treatment of Balb/c mice is also a relevant, reliable but significantly easier-to-perform preclinical model to identify novel pathomechanisms and targets in future HFrEF research., (© 2024 The Author(s). ESC Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology.)

The identification of novel drug targets is needed to improve the outcomes of heart failure (HF). G-protein-coupled receptors (GPCRs) represent the largest family of targets for already approved drugs, thus providing an opportunity for drug repurposing. Here, we aimed (i) to investigate the differential expressions of 288 cardiac GPCRs via droplet digital PCR (ddPCR) and bulk RNA sequencing (RNAseq) in a rat model of left ventricular pressure-overload; (ii) to compare RNAseq findings with those of ddPCR; and (iii) to screen and test for novel, translatable GPCR drug targets in HF. Male Wistar rats subjected to transverse aortic constriction (TAC, n = 5) showed significant systolic dysfunction vs. sham operated animals (SHAM, n = 5) via echocardiography. In TAC vs. SHAM hearts, RNAseq identified 69, and ddPCR identified 27 significantly differentially expressed GPCR mRNAs, 8 of which were identified using both methods, thus showing a correlation between the two methods. Of these, Prostaglandin-F2α-receptor ( Ptgfr ) was further investigated and localized on cardiomyocytes and fibroblasts in murine hearts via RNA-Scope. Antagonizing Ptgfr via AL-8810 reverted angiotensin-II-induced cardiomyocyte hypertrophy in vitro. In conclusion, using ddPCR as a novel screening method, we were able to identify GPCR targets in HF. We also show that the antagonism of Ptgfr could be a novel target in HF by alleviating cardiomyocyte hypertrophy.

Objective: During the COVID-19 pandemic, health system resources were reallocated to provide care for patients with COVID-19, limiting access for others. Patients themselves also constrained their visits to healthcare providers. In this study, we analysed the heterogeneous effects of the pandemic on the new diagnoses of lung, colorectal and breast cancer in Hungary., Design: Time series and panel models of quarterly administrative data, disaggregated by gender, age group and district of residence., Participants: Data for the whole population of Hungary between the first quarter of 2017 and the second quarter of 2021., Main Outcome Measures: Number of patients newly diagnosed with lung, colorectal and breast cancer, defined as those who were hospitalised with the appropriate primary International Classification of Diseases Tenth Revision diagnosis code but had not had hospital encounters with such a code within the previous 5 years., Results: The incidence of lung, colorectal and breast cancer decreased by 14.4% (95% CI 10.8% to 17.8%), 19.9% (95% CI 12.2% to 26.9%) and 15.5% (95% CI 2.5% to 27.0%), respectively, during the examined period of the pandemic, with different time patterns across cancer types. The incidence decreased more among people at least 65 years old than among the younger (p<0.05 for lung cancer and p<0.1 for colorectal cancer). At the district level, both the previously negative income gap in lung cancer incidence and the previously positive income gap in breast cancer incidence significantly narrowed during the pandemic (p<0.05)., Conclusions: The decline in new cancer diagnoses, caused by a combination of supply-side and demand-side factors, suggests that some cancer cases have remained hidden. It calls for action by policy makers to engage individuals with high risk of cancer more in accessing healthcare services, to diagnose the disease early and to prepare for effective management of patient pathways from diagnosis to survival or end-of-life care., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Little is known about the role of the neuropeptide somatostatin (SST) in myocardial ischemia/reperfusion injury and cardioprotection. Here, we investigated the direct cardiocytoprotective effect of SST on ischemia/reperfusion injury in cardiomyocyte cultures, as well as the expression of SST and its receptors in pig and human heart tissues. SST induced a bell-shaped, concentration-dependent cardiocytoprotection in both adult rat primary cardiomyocytes and H9C2 cells subjected to simulated ischemia/reperfusion injury. Furthermore, in a translational porcine closed-chest acute myocardial infarction model, ischemic preconditioning increased plasma SST-like immunoreactivity. Interestingly, SST expression was detectable at the protein, but not at the mRNA level in the pig left ventricles. SSTR1 and SSTR2 , but not the other SST receptors, were detectable at the mRNA level by PCR and sequencing in the pig left ventricle. Moreover, remote ischemic conditioning upregulated SSTR1 mRNA. Similarly, SST expression was also detectable in healthy human interventricular septum samples at the protein level. Furthermore, SST-like immunoreactivity decreased in interventricular septum samples of patients with ischemic cardiomyopathy. SSTR1, SSTR2, and SSTR5 but not SST and the other SST receptors were detectable at the mRNA level by sequencing in healthy human left ventricles. In addition, in healthy human left ventricle samples, SSTR1 and SSTR2 mRNAs were expressed especially in vascular endothelial and some other cell types as detected by RNA Scope ® in situ hybridization. This is the first demonstration that SST exerts a direct cardiocytoprotective effect against simulated ischemia/reperfusion injury. Moreover, SST is expressed in the heart tissue at the peptide level; however, it is likely to be of sensory neural origin since its mRNA is not detectable. SSTR1 and SSTR2 might be involved in the cardioprotective action of SST, but other mechanisms cannot be excluded., Competing Interests: PF is the founder and CEO of and BÁ is employed by Pharmahungary Group, a group of R&D companies (www.pharmahungary.com). The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Vörös, Sághy, Pohóczky, Makkos, Onódi, Brenner, Baranyai, Ágg, Váradi, Kemény, Leszek, Görbe, Varga, Giricz, Schulz, Helyes and Ferdinandy.)

Search for new cardioprotective therapies is of great importance since no cardioprotective drugs are available on the market. In line with this need, several natural biomolecules have been extensively tested for their potential cardioprotective effects. Previously, we have shown that biglycan, a member of a diverse group of small leucine-rich proteoglycans, enhanced the expression of cardioprotective genes and decreased ischemia/reperfusion-induced cardiomyocyte death via a TLR-4 dependent mechanism. Therefore, in the present study we aimed to test whether decorin, a small leucine-rich proteoglycan closely related to biglycan, could exert cardiocytoprotection and to reveal possible downstream signaling pathways. Methods: Primary cardiomyocytes isolated from neonatal and adult rat hearts were treated with 0 (Vehicle), 1, 3, 10, 30 and 100 nM decorin as 20 h pretreatment and maintained throughout simulated ischemia and reperfusion (SI/R). In separate experiments, to test the mechanism of decorin-induced cardio protection, 3 nM decorin was applied in combination with inhibitors of known survival pathways, that is, the NOS inhibitor L-NAME, the PKG inhibitor KT-5823 and the TLR-4 inhibitor TAK-242, respectively. mRNA expression changes were measured after SI/R injury. Results: Cell viability of both neonatal and adult cardiomyocytes was significantly decreased due to SI/R injury. Decorin at 1, 3 and 10 nM concentrations significantly increased the survival of both neonatal and adult myocytes after SI/R. At 3nM (the most pronounced protective concentration), it had no effect on apoptotic rate of neonatal cardiac myocytes. No one of the inhibitors of survival pathways (L-NAME, KT-5823, TAK-242) influenced the cardiocytoprotective effect of decorin. MYND-type containing 19 (Zmynd19) and eukaryotic translation initiation factor 4E nuclear import factor 1 (Eif4enif1) were significantly upregulated due to the decorin treatment. In conclusion, this is the first demonstration that decorin exerts a direct cardiocytoprotective effect possibly independent of NO-cGMP-PKG and TLR-4 dependent survival signaling.

The massive presence of phospholipids is demonstrated in frozen sections of human arterial thrombi. Purified platelet phospholipids and synthetic phospholipids retard in vitro tissue-type plasminogen activator (tPA)-induced fibrinolysis through effects on plasminogen activation and plasmin function. The inhibition of plasminogen activation on the surface of fibrin correlates with the fraction of anionic phospholipid. The phospholipids decrease the amount of tPA penetrating into the clot by 75% and the depth of the reactive surface layer occupied by the activator by up to 30%, whereas for plasmin both of these parameters decrease by approximately 50%. The phospholipids are not only a diffusion barrier, they also bind the components of the fibrinolytic system. Isothermal titration calorimetry shows binding characterized with dissociation constants in the range 0.35-7.64 microm for plasmin and tPA (lower values with more negative phospholipids). The interactions are endothermic and thermodynamically driven by an increase in entropy, probably caused by the rearrangements in the ordered gel structure of the phospholipids (in line with the stronger inhibition at gel phase temperatures compared with liquid crystalline phase temperatures). These findings show a phospholipid barrier, which should be overcome during lysis of arterial thrombi.

Myosin modulates the fibrinolytic process as a cofactor of the tissue plasminogen activator and as a substrate of plasmin. We report now that myosin is present in arterial thrombi and it forms reversible noncovalent complexes with fibrinogen and fibrin with equilibrium dissociation constants in the micromolar range (1.70 and 0.94 microM, respectively). Competition studies using a peptide inhibitor of fibrin polymerization (glycl-prolyl-arginyl-proline [GPRP]) indicate that myosin interacts with domains common in fibrinogen and fibrin and this interaction is independent of the GPRP-binding polymerization site in the fibrinogen molecule. An association rate constant of 1.81 x 10(2) M(-1) x s(-1) and a dissociation rate constant of 3.07 x 10(-4) s(-1) are determined for the fibrinogen-myosin interaction. Surface plasmon resonance studies indicate that fibrin serves as a matrix core for myosin aggregation. The fibrin clots equilibrated with myosin are stabilized against dissolution initiated by plasminogen and tissue-type plasminogen activator (tPA) or urokinase (at fibrin monomer-myosin molar ratio as high as 30) and by plasmin under static and flow conditions (at fibrin monomer-myosin molar ratio lower than 15). Myosin exerts similar effects on the tPA-induced dissolution of blood plasma clots. Covalent modification involving factor XIIIa does not contribute to this stabilizing effect; myosin is not covalently attached to the clot by the time of complete cross-linking of fibrin. Thus, our in vitro data suggest that myosin detected in arterial thrombi binds to the polymerized fibrin, in the bound form its tPA-cofactor properties are masked, and the myosin fibrin clot is relatively resistant to plasmin.