Candesartan Cilexetil Attenuates Arrhythmogenicity Following Pressure Overload in Rats via the Modulation of Cardiac Electrical and Structural Remodeling and Calcium Handling Dysfunction

Vericiguat alleviates ventricular remodeling and arrhythmias in mouse models of myocardial infarction via CaMKII signaling

AIMS

Maladaptive ventricular remodeling is a major cause of ventricular arrhythmias following myocardial infarction (MI) and adversely impacts the quality of life of affected patients. Vericiguat is a new soluble guanylate cyclase (sGC) activator with cardioprotective properties. However, its effects on MI-induced ventricular remodeling and arrhythmias are not fully comprehended; hence, our research evaluated the effect of vericiguat on mice post-MI.

MATERIALS AND METHODS

Mice were divided into four treatment groups: Sham, Sham+Veri, MI, and MI + Veri. For the MI groups and MI + Veri groups, the left anterior descending (LAD) coronary artery was occluded to induce MI. Conversely, the Sham group underwent mock surgery. Vericiguat was administered orally daily for 28 days to the Sham+Veri and MI + Veri groups. Additionally, H9c2 cells were cultured for further mechanistic studies. Assessment methods included echocardiography, pathological analysis, electrophysiological analysis, and Western blotting.

KEY FINDINGS

Vericiguat reduced cardiac dysfunction and infarct size after MI. It also mitigated MI-induced left ventricular fibrosis and cardiomyocyte apoptosis. Vericiguat normalized the expression of ion channel proteins (Kv4.3, Kv4.2, Kv2.1, Kv1.5, Kv7.1, KCNH2, Cav1.2) and the gap junction protein connexin 43, reducing the susceptibility to ventricular arrhythmia. Vericiguat significantly inhibited MI-induced calcium/calmodulin-dependent protein kinase II (CaMKII) pathway activation in mice.

SIGNIFICANCE

Vericiguat alleviated MI-induced left ventricular adverse remodeling and arrhythmias through modulation of the CamkII signaling pathway.

A randomized trial of genotype-guided perindopril use

OBJECTIVE

Cough caused by angiotensin-converting enzyme inhibitors (ACEIs) limits their clinical application and cardiovascular benefits. This randomized trial investigated whether genotype-guided perindopril use could reduce drug-related cough in 20 to 79-year-old individuals with hypertension.

METHODS

After screening 120 patients and randomization, 68 were assigned to genotyping ( n  = 41) and control ( n  = 27) groups. NELL1 p.Arg382Trp (rs8176786) and intron (rs10766756) genotype information was used to subdivide the genotyping group into high-risk and low-risk subgroups with at least one or no risk alleles for ACEI-related cough, respectively. The high-risk subgroup received candesartan (8 mg/day) for 6 weeks, whereas the low-risk subgroup received perindopril (4 mg/day). The control group, which was not genotyped, received perindopril (4 mg/day). The primary outcome variables were cough and moderate/severe cough; the secondary outcome variable was any adverse event.

RESULTS

During the 6-week period, the risk of cough was lower in the genotyping group than in the control group [five (12.2%) and nine (33.3%) participants, respectively; hazard ratio: 0.25; log-rank P  = 0.017]. The moderate/severe cough risk was also lower in the genotyping group [one (2.4%) and five (18.5%) participants, respectively; hazard ratio: 0.12; log-rank P  = 0.025]. Differences in cough (hazard ratio: 0.56; log-rank P  = 0.32) and moderate/severe cough risk (hazard ratio: 0.26; log-rank P  = 0.19) between the low-risk and control groups were not significant. The risk of total adverse events was similar between any two groups.

CONCLUSION

Cough risk was lower during genotype-guided treatment than during conventional treatment. These results support the utility of NELL1 variant data in clinical decision making to personalize renin-angiotensin system blocker therapy use.

TRIAL REGISTRATION

ClinicalTrials.gov number: NCT05535595 (retrospectively registered at September 7, 2022).

Qi-Po-Sheng-Mai granule ameliorates Ach-CaCl2 -induced atrial fibrillation by regulating calcium homeostasis in cardiomyocytes

BACKGROUND

Atrial fibrillation (AF) is one of the most common arrhythmias encountered in clinical settings. Currently, the pathophysiology of AF remains unclear, which severely limits the effectiveness and safety of medical therapies. The Chinese herbal formula Qi-Po-Sheng-Mai Granule (QPSM) has been widely used in China to treat AF. However, its pharmacological and molecular mechanisms remain unknown.

PURPOSE

The purpose of this study was to investigate the molecular mechanisms and potential targets of QPSM for AF.

STUDY DESIGN AND METHODS

The AF model was induced by Ach (66 μg/ml) and CaCl2 (10 mg/kg), and the dose of 0.1 ml/100 g was injected into the tail vein for 5 weeks. QPSM was administered daily at doses of 4.42 and 8.84 g/kg, and amiodarone (0.18 g/kg) was used as the positive control. The effect of QPSM on AF was assessed by electrocardiogram, echocardiography, and histopathological analysis. Then, we employed network pharmacology with single nucleus RNA sequencing (snRNA-Seq) to investigate the molecular mechanisms and potential targets of QPSM for AF. Furthermore, high performance liquid chromatography (HPLC) method was used for component analysis of QPSM, and molecular docking was used to verify the potential targets. Using the IonOptix single cell contraction and ion synchronization test equipment, single myocyte length and calcium ion variations were observed in real time. The expression levels of calcium Transporter-related proteins were detected by western blot and immunohistochemistry.

RESULTS

Based on an Ach-CaCl2-induced AF model, we found that QPSM treatment significantly reduced atrial electrical remodeling-related markers, such as AF inducibility and duration, and attenuated atrial dilation and fibrosis. Network pharmacology identified 52 active ingredients and 119 potential targets for QPSM in the treatment of AF, and 45 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were enriched, among which calcium pathway had the greatest impact. Using single nucleus sequencing (snRNA-seq), we identified cardiomyocytes as the most differentially expressed in response to drug treatment, with nine differentially expressed genes enriched in calcium signaling pathways. High performance liquid chromatography and molecular docking confirmed that the core components of QPSM strongly bind to the key factors in the calcium signaling pathway. Additional experiments have shown that QPSM increases calcium transients (CaT) and contractility in the individual cardiomyocyte. This was accomplished by increasing the expression of CACNA1C and SERCA2a and decreasing the expression of CAMK2B and NCX1.

CONCLUSION

The present study has systematically elucidated the role of QPSM in maintaining calcium homeostasis in cardiomyocytes through the regulation of calcium transporters, which could lead to new drug development ideas for AF.