A novel glycopeptide from mountain-cultivated ginseng residue protects type 2 diabetic symptoms-induced heart failure.

ETHNOPHARMACOLOGICAL RELEVANCE: Mountain-cultivated Panax ginseng C.A.Mey. (MCG) with high market price and various properties was valuable special local product in Northeast of Asia. MCG has been historically used to mitigate heart failure (HF) for thousand years, HF is a clinical manifestation of deficiency of "heart-qi" in traditional Chinese medicine. However, there was little report focus on the activities of extracted residue of MCG. AIM OF THE STUDY: A novel glycopeptide (APMCG-1) was isolated from step ethanol precipitations of alkaline protease-assisted extract from MCG residue. MATERIALS AND METHODS: The molecular weight and subunit structure of APMCG-1 were determined by FT-IR, HPLC and GPC technologies, as well as the H9c2 cells, Tg (kdrl:EGFP) zebrafish were performed to evaluated the protective effect of APMCG-1. RESULTS: APMCG-1 was identified as a glycopeptide containing seven monosaccharides and seven amino acids via O-lined bonds. Further, in vitro, APMCG-1 significantly decreased reactive oxygen species production and lactate dehydrogenase contents in palmitic acid (PA)-induced H9c2 cells. APMCG-1 also attenuated endoplasmic reticulum stress and mitochondria-mediated apoptosis in H9c2 cells via the PI3K/AKT signaling pathway. More importantly, APMCG-1 reduced the blood glucose, lipid contents, the levels of heart injury, oxidative stress and inflammation of 5 days post fertilization Tg (kdrl:EGFP) zebrafish with type 2 diabetic symptoms in vivo. CONCLUSIONS: APMCG-1 protects PA-induced H9c2 cells while reducing cardiac dysfunction in zebrafish with type 2 diabetic symptoms. The present study provides a new insight into the development of natural glycopeptides as heart-related drug therapies.

In vivo and in vitro study on the regulatory mechanism of XiaoChaiHu decoction on PANoptosis in sepsis-induced cardiomyopathy.

ETHNOPHARMACOLOGICAL RELEVANCE: In accordance with the tenets of traditional Chinese medicine, sepsis is categorized into three distinct syndromes: heat syndrome, blood stasis syndrome, and deficiency syndrome. Xiaochaihu decoction (XCHD) has many functions, including the capacity to protect the liver, cholagogue, antipyretic, anti-inflammatory, and anti-pathogenic microorganisms. XCHD exerts the effect of clearing heat and reconciling Shaoyang. The XCHD contains many efficacious active ingredients, yet the mechanism of sepsis-induced cardiomyopathy (SIC) remains elusive. AIM OF THE STUDY: To investigate the molecular mechanisms underlying the protective effects of XCHD against SIC using an integrated approach combining network pharmacology and molecular biology techniques. MATERIALS AND METHODS: Network pharmacology methods identified the active ingredients, target proteins, and pathways affected by XCHD in the context of SIC. We conducted in vivo experiments using mice with lipopolysaccharide-induced SIC, evaluating cardiac function through echocardiography and histology. XCHD-containing serum was analyzed to determine its principal active components using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The effects of XCHD-containing serum on SIC were further tested in vitro in LPS-treated H9c2 cardiac cells. Protein expression levels were quantified via Western blotting and enzyme-linked immunosorbent assay (ELISA). Additionally, molecular docking was performed between the active components and ZBP1, a potential target protein. Overexpression of ZBP1 in H9c2 cells allowed for a deeper exploration of its role in modulating SIC-associated gene expression. RESULTS: UPLC-MS/MS identified 31 shared XCHD and XCHD-containing serum components. These included organic acids, terpenoids, and flavonoids, which have been identified as the active components of XCHD. Our findings revealed that XCHD alleviated LPS-induced myocardial injury, improved cardiac function, and preserved cardiomyocyte morphology in mice. In vitro studies, we demonstrated that XCHD-containing serum significantly suppressed the expression of inflammatory cytokines (IL-6, IL-1ß, and TNF-α) in LPS-induced H9c2 cells. Mechanistic investigations showed that XCHD downregulated genes associated with PANoptosis, a novel cell death pathway, suggesting its protective role in sepsis-damaged hearts. Conversely, overexpression of ZBP1 abolished the protective effects of XCHD and amplified PANoptosis-related gene expression. CONCLUSIONS: Our study provides the first evidence supporting the protective effects of XCHD against SIC, both in vitro and in vivo. The underlying mechanism involves the inhibition of ZBP1-initiated PANoptosis, offering new insights into treating SIC using XCHD.

Enhancing miR-19a/b induced cardiomyocyte proliferation in infarcted hearts by alleviating oxidant stress and controlling miR-19 release.

Fully restoring the lost population of cardiomyocytes and heart function remains the greatest challenge in cardiac repair post myocardial infarction. In this study, a pioneered highly ROS-eliminating hydrogel was designed to enhance miR-19a/b induced cardiomyocyte proliferation by lowering the oxidative stress and continuously releasing miR-19a/b in infarcted myocardium in situ. In vivo lineage tracing revealed that ∼20.47 % of adult cardiomyocytes at the injected sites underwent cell division in MI mice. In MI pig the infarcted size was significantly reduced from 40 % to 18 %, and thereby marked improvement of cardiac function and increased muscle mass. Most importantly, our treatment solved the challenge of animal death--all the treated pigs managed to live until their hearts were harvested at day 50. Therefore, our strategy provides clinical conversion advantages and safety for healing damaged hearts and restoring heart function post MI, which will be a powerful tool to battle cardiovascular diseases in patients.

Effects and mechanisms of Salvia miltiorrhiza Bunge extract on myocardial cell apoptosis in rat heart failure model.

PURPOSE: This work aimed to investigate the effects of Tanshinone IIA (Tan IIA) on myocardial cell (MC) apoptosis in a rat model of heart failure (HF). METHODS: Tan IIA was extracted from Salvia miltiorrhiza Bunge (SMB) using an ethanol reflux method. Fifty rats were randomly divided into five groups: sham (no treatment), mod (HF model establishment), low dose (LD: 0.1 mL/kg Tan IIA), medium dose (MD: 0.3 mL/kg Tan IIA), and high dose (HD: 0.5 mL/kg Tan IIA), with 10 rats in each group. The effects of different doses of Tan IIA on cardiac function, MC apoptosis, and the levels of proteins associated with the PI3K/Akt/mTOR signaling pathway were compared. RESULTS: Mod group showed a significant decrease in systolic arterial pressure, mean arterial pressure, heart rate, left ventricular systolic pressure, left ventricular ejection fraction, left ventricular fractional shortening, and the levels of p-PI3K, p-Akt, and p-mTOR proteins versus sham group (p < 0.05). Additionally, the left ventricular end-diastolic diameter (LVIDd), end-systolic diameter, diastolic pressure, and MC apoptosis were significantly increased (p < 0.05). LD, MD, and HD groups exhibited significant improvements across various indicators of cardiac function and MC apoptosis versus mod group (p < 0.05). CONCLUSIONS: Tan IIA may improve cardiac function and inhibit MC apoptosis in rats with HF by modulating the PI3K/Akt/mTOR signaling pathway.

The enhancing effects of selenomethionine on harmine in attenuating pathological cardiac hypertrophy via glycolysis metabolism.

Pathological cardiac hypertrophy, a common feature in various cardiovascular diseases, can be more effectively managed through combination therapies using natural compounds. Harmine, a ß-carboline alkaloid found in plants, possesses numerous pharmacological functions, including alleviating cardiac hypertrophy. Similarly, Selenomethionine (SE), a primary organic selenium source, has been shown to mitigate cardiac autophagy and alleviate injury. To explores the therapeutic potential of combining Harmine with SE to treat cardiac hypertrophy. The synergistic effects of SE and harmine against cardiac hypertrophy were assessed in vitro with angiotensin II (AngII)-induced hypertrophy and in vivo using a Myh6R404Q mouse model. Co-administration of SE and harmine significantly reduced hypertrophy-related markers, outperforming monotherapies. Transcriptomic and metabolic profiling revealed substantial alterations in key metabolic and signalling pathways, particularly those involved in energy metabolism. Notably, the combination therapy led to a marked reduction in the activity of key glycolytic enzymes. Importantly, the addition of the glycolysis inhibitor 2-deoxy-D-glucose (2-DG) did not further potentiate these effects, suggesting that the antihypertrophic action is predominantly mediated through glycolytic inhibition. These findings highlight the potential of SE and harmine as a promising combination therapy for the treatment of cardiac hypertrophy.

Regression of postprandial cardiac hypertrophy in burmese pythons is mediated by FoxO1.

As ambush-hunting predators that consume large prey after long intervals of fasting, Burmese pythons evolved with unique adaptations for modulating organ structure and function. Among these is cardiac hypertrophy that develops within three days following a meal (Andersen et al., 2005, Secor, 2008), which we previously showed was initiated by circulating growth factors (Riquelme et al., 2011). Postprandial cardiac hypertrophy in pythons also rapidly regresses with subsequent fasting (Secor, 2008); however, the molecular mechanisms that regulate the dynamic cardiac remodeling in pythons during digestion are largely unknown. In this study, we employed a multiomics approach coupled with targeted molecular analyses to examine remodeling of the python ventricular transcriptome and proteome throughout digestion. We found that forkhead box protein O1 (FoxO1) signaling was suppressed prior to hypertrophy development and then activated during regression, which coincided with decreased and then increased expression, respectively, of FoxO1 transcriptional targets involved in proteolysis. To define the molecular mechanistic role of FoxO1 in hypertrophy regression, we used cultured mammalian cardiomyocytes treated with postfed python plasma. Hypertrophy regression both in pythons and in vitro coincided with activation of FoxO1-dependent autophagy; however, the introduction of a FoxO1-specific inhibitor prevented both regression of cell size and autophagy activation. Finally, to determine whether FoxO1 activation could induce regression, we generated an adenovirus expressing a constitutively active FoxO1. FoxO1 activation was sufficient to prevent and reverse postfed plasma-induced hypertrophy, which was partially prevented by autophagy inhibition. Our results indicate that modulation of FoxO1 activity contributes to the dynamic ventricular remodeling in postprandial Burmese pythons.

The role and possible mechanism of the ferroptosis-related SLC7A11/GSH/GPX4 pathway in myocardial ischemia-reperfusion injury.

BACKGROUND: Myocardial ischemia-reperfusion injury (MI/RI) is an unavoidable risk event for acute myocardial infarction, with ferroptosis showing close involvement. We investigated the mechanism of MI/RI inducing myocardial injury by inhibiting the ferroptosis-related SLC7A11/glutathione (GSH)/glutathione peroxidase 4 (GPX4) pathway and activating mitophagy. METHODS: A rat MI/RI model was established, with myocardial infarction area and injury assessed by TTC and H&E staining. Rat cardiomyocytes H9C2 were cultured in vitro, followed by hypoxia/reoxygenation (H/R) modeling and the ferroptosis inhibitor lipoxstatin-1 (Lip-1) treatment, or 3-Methyladenine or rapamycin treatment and overexpression plasmid (oe-SLC7A11) transfection during modeling. Cell viability and death were evaluated by CCK-8 and LDH assays. Mitochondrial morphology was observed by transmission electron microscopy. Mitochondrial membrane potential was detected by fluorescence dye JC-1. Levels of inflammatory factors, reactive oxygen species (ROS), Fe2+, malondialdehyde, lipid peroxidation, GPX4 enzyme activity, glutathione reductase, GSH and glutathione disulfide, and SLC7A11, GPX4, LC3II/I and p62 proteins were determined by ELISA kit, related indicator detection kits and Western blot. RESULTS: The ferroptosis-related SLC7A11/GSH/GPX4 pathway was repressed in MI/RI rat myocardial tissues, inducing myocardial injury. H/R affected GSH synthesis and inhibited GPX4 enzyme activity by down-regulating SLC7A11, thus promoting ferroptosis in cardiomyocytes, which was averted by Lip-1. SLC7A11 overexpression improved H/R-induced cardiomyocyte ferroptosis via the GSH/GPX4 pathway. H/R activated mitophagy in cardiomyocytes. Mitophagy inhibition reversed H/R-induced cellular ferroptosis. Mitophagy activation partially averted SLC7A11 overexpression-improved H/R-induced cardiomyocyte ferroptosis. H/R suppressed the ferroptosis-related SLC7A11/GSH/GPX4 pathway by inducing mitophagy, leading to cardiomyocyte injury. CONCLUSIONS: Increased ROS under H/R conditions triggered cardiomyocyte injury by inducing mitophagy to suppress the ferroptosis-related SLC7A11/GSH/GPX4 signaling pathway activation.

ß-Adrenergic receptor signalling pathway mediated antiarrhythmic activity of s-limonene in the rat heart.

S-Limonene (s-Lim) is a monocyclic monoterpene found in a variety of plants and has been shown to present antioxidant and cardioprotective activity in experimental models of myocardial infarction. The aim of this study was to evaluate the potential mechanism by which s-Lim exerts its antiarrhythmic effect, focusing on the blockade of ß-adrenoceptor (ß-AR) and its effects on various in vivo and in vitro parameters, including electrocardiogram (ECG) measurements, left ventricular developed pressure (LVDP), the ß-adrenergic pathway, sarcomeric shortening and L-type calcium current (ICa,L). In isolated hearts, 10 µM of s-Lim did not alter the ECG profile or LVPD. s-Lim increased the heart rate corrected QT interval (QTc) (10.8%) at 50 µM and reduced heart rate at the concentrations of 30 (12.4%) and 50 µM (16.6%). s-Lim (10 µM) also inhibited the adrenergic response evoked by isoproterenol (ISO) (1 µM) reducing the increased of heart rate, LVDP and ECG changes. In ventricular cardiomyocyte, s-Lim antagonized the effect of dobutamine by preventing the increase of sarcomeric shortening, demonstrating a similar effect to atenolol (blocker ß1-AR). In vivo, s-Lim antagonized the effect of ISO (agonists ß1-AR), presenting a similar effect to propranolol (a non-selective blocker ß-AR). In ventricular cardiomyocyte, s-Lim did not alter the voltage dependence for ICa,L activation or the ICa,L density. In addition, s-Lim did not affect changes in the ECG effect mediated by 5 µM forskolin (an activator of adenylate cyclase). In an in vivo caffeine/ISO-induced arrhythmia model, s-Lim (1 mg/kg) presented antiarrhythmic action verified by a reduced arrhythmia score, heart rate, and occurrence of ventricular premature beats and inappropriate sinus tachycardia. These findings indicate that the antiarrhythmic activity of s-Lim is related to blockade of ß-AR in the heart.

Adenylate cyclase 1 knockdown attenuates pirarubicin-induced cardiotoxicity.

This study aimed to investigate the effects and possible mechanisms of adenylate cyclase 1 (ADCY1) on pirarubicin-induced cardiomyocyte injury. HL-1 cells were treated with pirarubicin (THP) to induce intracellular toxicity, and the extent of damage to mouse cardiomyocytes was assessed using CCK-8, Edu, flow cytometry, ROS, ELISA, RT-qPCR and western blotting. THP treatment reduced the viability of HL-1 cells, inhibited proliferation, induced apoptosis and triggered oxidative stress. In addition, the RT-qPCR results revealed that ADCY1 expression was significantly elevated in HL-1 cells, and molecular docking showed a direct interaction between ADCY1 and THP. Western blotting showed that ADCY1, phospho-protein kinase A and GRIN2D expression were also significantly elevated. Knockdown of ADCY1 attenuated THP-induced cardiotoxicity, possibly by regulating the ADCY1/PKA/GRIN2D pathway.

Resveratrol as a cardioprotective adjuvant for 5-fluorouracil in the treatment of gastric cancer cells.

The clinical application of 5-fluorouracil (5-Fu), a potent chemotherapeutic agent, is often hindered by its well-documented cardiotoxic effects. Nevertheless, natural polyphenolic compounds like resveratrol (RES), known for their dual anti-tumor and cardioprotective properties, are potential adjunct therapeutic agents. In this investigation, we examined the combined utilization of RES and 5-Fu for the inhibition of gastric cancer using both in vitro and in vivo models, as well as their combined impact on cardiac cytotoxicity. Our study revealed that the co-administration of RES and 5-Fu effectively suppressed MFC cell viability, migration, and invasion, while also reducing tumor weight and volume. Mechanistically, the combined treatment prompted p53-mediated apoptosis and autophagy, leading to a considerable anti-tumor effect. Notably, RES mitigated the heightened oxidative stress induced by 5-Fu in cardiomyocytes, suppressed p53 and Bax expression, and elevated Bcl-2 levels. This favorable influence enhanced primary cardiomyocyte viability, decreased apoptosis and autophagy, and mitigated 5-Fu-induced cardiotoxicity. In summary, our findings suggested that RES holds promise as an adjunct therapy to enhance the efficacy of gastric cancer treatment in combination with 5-Fu, while simultaneously mitigating cardiotoxicity.

Minocycline alleviates lipopolysaccharide-induced cardiotoxicity by suppressing the NLRP3/Caspase-1 signaling pathway.

Minocycline (Min), as an antibiotic, possesses various beneficial properties such as anti-inflammatory, antioxidant, and anti-apoptotic effects. Despite these known qualities, the precise cardioprotective effect and mechanism of Min in protecting against sepsis-induced cardiotoxicity (SIC) remain unspecified. To address this, our study sought to assess the protective effects of Min on the heart. Lipopolysaccharide (LPS) was utilized to establish a cardiotoxicity model both in vivo and in vitro. Min was pretreated in the models. In the in vivo setting, evaluation of heart tissue histopathological injury was performed using hematoxylin and eosin (H&E) staining and TUNEL. Immunohistochemistry (IHC) was employed to evaluate the expression levels of NLRP3 and Caspase-1 in the heart tissue of mice. During in vitro experiments, the viability of H9c2 cells was gauged utilizing the CCK8 assay kit. Intracellular ROS levels in H9c2 cells were quantified using a ROS assay kit. Both in vitro and in vivo settings were subjected to measurement of oxidative stress indexes, encompassing glutathione (GSH), malondialdehyde (MDA), and superoxide dismutase (SOD) levels. Additionglly, myocardial injury markers like lactate dehydrogenase (LDH) and creatine kinase MB (CK-MB) activity were quantified using appropriate assay kits. Western blotting (WB) analysis was conducted to detect the expression levels of NOD-like receptor protein-3 (NLRP3), caspase-1, IL-18, and IL-1ß, alongside apoptosis-related proteins such as Bcl-2 and Bax, and antioxidant proteins including superoxide dismutase-1 (SOD-1) and antioxidant proteins including superoxide dismutase-1 (SOD-2), both in H9c2 cells and mouse heart tissues. In vivo, Min was effective in reducing LPS-induced inflammation in cardiac tissue, preventing cell damage and apoptosis in cardiomyocytes. The levels of LDH and CK-MB were significantly reduced with Min treatment. In vitro studies showed that Min improved the viability of H9C2 cells, reduced apoptosis, and decreased ROS levels in these cells. Further analysis indicated that Min decreased the protein levels of NLRP3, Caspase-1, IL-18, and IL-1ß, while increasing the levels of SOD-1 and SOD-2 both in vivo and in vitro. Min alleviates LPS-induced SIC by suppressing the NLRP3/Caspase-1 signalling pathway in vivo and in vitro.

The study on the role of O-GlcNAcylation of SIRT3 in regulating mitochondrial oxidative stress during simulate myocardial ischemia-reperfusion.

Myocardial ischemia-reperfusion injury (MIRI) is a significant complication following reperfusion therapy after myocardial infarction. Mitochondrial oxidative stress is a critical factor in MIRI, and Sirtuin 3 (SIRT3), as a major mitochondrial deacetylase, plays a key protective role, with its activity potentially regulated by O-GlcNAcylation. This study used the H9C2 cell line to establish a simulated ischemia/reperfusion (SI/R) model, we utilized co-immunoprecipitated to validate the relationship between O-GlcNAc transferase (OGT) and SIRT3, demonstrated SIRT3 O-GlcNAcylation sites through LC-MS/MS, and performed site mutations using CRISPR/Cas9 technology. The results were validated using immunoblotting. SIRT3 and superoxide dismutase 2 (SOD2) activities were detected using a fluorometric assay, while mitochondrial reactive oxygen species (MROS) levels and cellular apoptosis were assessed using immunofluorescence. We have identified an interaction between SIRT3 and OGT, where SIRT3 undergoes dynamic O-GlcNAcylation at the S190 site, facilitating SIRT3 deacetylase activity. During SI/R, elevated levels of O-GlcNAcylation activate SOD2 by promoting SIRT3 enzyme activity, thereby inhibiting excessive MROS production. This significantly mitigates the occurrence of malignant autophagy in myocardial cells during reperfusion, promoting their survival. Conversely, blocking SIRT3 O-GlcNAcylation at the S190 site exacerbates SI/R injury. We demonstrate that O-GlcNAcylation is a crucial post-translational modification (PTM) of SIRT3 during SI/R, shedding light on a promising mechanism for future therapeutic approaches.

Combined ROS Sensitive PEG-PPS-PEG with Peptide Agonist for Effective Target Therapy in Mouse Model.

Background and Purpose: Growth hormone-releasing hormone (GHRH) agonist, a 29-amino acid peptide, shows significant potential in treating myocardial infarction (MI) by aiding the repair of injured heart tissue. The challenge lies in the effective on-site delivery of GHRH agonist. This study explores the use of a targetable delivery system employing ROS-responsive PEG-PPS-PEG polymers to encapsulate and deliver GHRH agonist MR409 for enhanced therapeutic efficacy. Methods: We synthesized a self-assembling poly (ethylene glycol)-poly (propylene sulfide)-poly (ethylene glycol) polymer (PEG-PPS-PEG) amphiphilic polymer responsive to reactive oxygen species (ROS). The hydrophilic peptide GHRH agonist MR409 was encapsulated within these polymers to form nano PEG-PPS-PEG@MR409 vesicles (NPs). Cardiomyocyte apoptosis was induced under hypoxia and serum-free culture condition for 24 hours, and their production of ROS was detected by fluorescence dye staining. The cellular uptake of PEG-PPS-PEG@MR409 NPs was observed using fluorescence-labeled MR409. Targeting ability and therapeutic efficacy were evaluated using a mouse MI model. Results: PEG-PPS-PEG@MR409 NPs were efficiently internalized by cardiomyocytes, reducing ROS levels and apoptosis. These NPs exhibited superior targeting to the infarcted heart compared to naked MR409 peptide. With a reduced injection frequency (once every three days), PEG-PPS-PEG@MR409 NPs significantly promoted cardiac function recovery post-MI, matching the efficacy of daily MR409 injections. Conclusion: ROS-responsive PEG-PPS-PEG polymers provide a novel and effective platform for the targeted delivery of GHRH agonist peptides, improving cardiac function and offering a new approach for peptide therapy in MI treatment.

MiR-495-3p promotes cardiac hypertrophy by targeting Pum2.

Pathological cardiac hypertrophy (CH) may lead to heart failure and sudden death. MicroRNAs (miRNAs) have been documented to play crucial parts in CH. The objective of this research was to discuss the potential along with molecule mechanism of miR-495-3p in CH. In vivo CH model was induced by aortic banding (AB) in rats. Cellular hypertrophy in H9c2 rat cardiomyocytes was stimulated by angiotensin II (Ang II) treatment. Haematoxylin and eosin (HE), echocardiography and immunofluorescence staining were used to examine the alterations in cardiac function. The outcomes showed that miR-495-3p expression was high in rat model as well as in Ang II-stimulated cardiomyocytes. Besides, silenced miR-495-3p attenuated CH both in vitro and in vivo. Mechanically, miR-495-3p bound to pumilio RNA binding family member 2 (Pum2) 3'UTR and silenced its expression. Rescue assays further notarized that Pum2 silence abrogated the inhibitory impacts of miR-495-3p inhibitor on CH. In a word, the present research uncovered that miR-495-3p promoted CH by targeting Pum2. Therefore, miR-495-3p may be a novel therapeutic molecule for this disease.

A new paradigm for generating high-quality cardiac pacemaker cells from mouse pluripotent stem cells.

Cardiac biological pacing (BP) is one of the future directions for bradyarrhythmias intervention. Currently, cardiac pacemaker cells (PCs) used for cardiac BP are mainly derived from pluripotent stem cells (PSCs). However, the production of high-quality cardiac PCs from PSCs remains a challenge. Here, we developed a cardiac PC differentiation strategy by adopting dual PC markers and simulating the developmental route of PCs. First, two PC markers, Shox2 and Hcn4, were selected to establish Shox2:EGFP; Hcn4:mCherry mouse PSC reporter line. Then, by stepwise guiding naïve PSCs to cardiac PCs following naïve to formative pluripotency transition and manipulating signaling pathways during cardiac PCs differentiation, we designed the FSK method that increased the yield of SHOX2+; HCN4+ cells with typical PC characteristics, which was 12 and 42 folds higher than that of the embryoid body (EB) and the monolayer M10 methods respectively. In addition, the in vitro cardiac PCs differentiation trajectory was mapped by single-cell RNA sequencing (scRNA-seq), which resembled in vivo PCs development, and ZFP503 was verified as a key regulator of cardiac PCs differentiation. These PSC-derived cardiac PCs have the potential to drive advances in cardiac BP technology, help with the understanding of PCs (patho)physiology, and benefit drug discovery for PC-related diseases as well.

Transcriptome analysis reveals EBF1 ablation-induced injuries in cardiac system.

Rationale: Regulatory processes of transcription factors (TFs) shape heart development and influence the adult heart's response to stress, contributing to cardiac disorders. Despite their significance, the precise mechanisms underpinning TF-mediated regulation remain elusive. Here, we identify that EBF1, as a TF, is highly expressed in human heart tissues. EBF1 is reported to be associated with human cardiovascular disease, but its roles are unclear in heart. In this study, we investigated EBF1 function in cardiac system. Methods: RNA-seq was utilized to profile EBF1 expression patterns. CRISPR/Cas9 was utilized to knock out EBF1 to investigate its effects. Human pluripotent stem cells (hPSCs) differentiated into cardiac lineages were used to mimic cardiac development. Cardiac function was evaluated on mouse model with Ebf1 knockout by using techniques such as echocardiography. RNA-seq was conducted to analyze transcriptional perturbations. ChIP-seq was employed to elucidate EBF1-bound genes and the underlying regulatory mechanisms. Results: EBF1 was expressed in some human and mouse cardiomyocyte. Knockout of EBF1 inhibited cardiac development. ChIP-seq indicated EBF1's binding on promoters of cardiogenic TFs pivotal to cardiac development, facilitating their transcriptional expression and promoting cardiac development. In mouse, Ebf1 depletion triggered transcriptional perturbations of genes, resulting in cardiac remodeling. Mechanistically, we found that EBF1 directly bound to upstream chromatin regions of cardiac hypertrophy-inducing genes, contributing to cardiac hypertrophy. Conclusions: We uncover the mechanisms underlying EBF1-mediated regulatory processes, shedding light on cardiac development, and the pathogenesis of cardiac remodeling. These findings emphasize EBF1's critical role in orchestrating diverse aspects of cardiac processes and provide a promising therapeutic intervention for cardiomyopathy.

Nicotinamide Riboside-Driven Modulation of SIRT3/mtROS/JNK Signaling Pathways Alleviates Myocardial Ischemia-Reperfusion Injury.

Myocardial ischemia-reperfusion (I/R) injury exacerbates cellular damage upon restoring blood flow to ischemic cardiac tissue, causing oxidative stress, inflammation, and apoptosis. This study investigates Nicotinamide Riboside (NR), a precursor of nicotinamide adenine dinucleotide (NAD+), for its cardioprotective effects. Administering NR to mice before I/R injury and evaluating heart function via echocardiography showed that NR significantly improved heart function, increased left ventricular ejection fraction (LVEF) and fractional shortening (FS), and reduced left ventricular end-diastolic (LVDd) and end-systolic diameters (LVSd). NR also restored E/A and E/e' ratios. It reduced cardiomyocyte apoptosis both in vivo and in vitro, inhibiting elevated caspase-3 activity and returning Bax protein levels to normal. In vitro, NR reduced the apoptotic rate in hydrogen peroxide (H2O2)-treated HL-1 cells from 30% to 10%. Mechanistically, NR modulated the SIRT3/mtROS/JNK pathway, reversing H2O2-induced SIRT3 downregulation, reducing mitochondrial reactive oxygen species (mtROS), and inhibiting JNK activation. Using SIRT3-knockout (SIRT3-KO) mice, we confirmed that NR's cardioprotective effects depend on SIRT3. Echocardiography showed that NR's benefits were abrogated in SIRT3-KO mice. In conclusion, NR provides significant cardioprotection against myocardial I/R injury by enhancing NAD+ levels and modulating the SIRT3/mtROS/JNK pathway, suggesting its potential as a novel therapeutic agent for ischemic heart diseases, meriting further clinical research.

Cell swelling enhances ligand-driven ß-adrenergic signaling.

G protein-coupled receptors' conformational landscape can be affected by their local, microscopic interactions within the cell plasma membrane. We employ here a pleiotropic stimulus, namely osmotic swelling, to alter the cortical environment within intact cells and monitor the response in terms of receptor function and downstream signaling. We observe that in osmotically swollen cells the ß2-adrenergic receptor, a prototypical GPCR, favors an active conformation, resulting in cAMP transient responses to adrenergic stimulation that have increased amplitude. The results are validated in primary cell types such as adult cardiomyocytes, a model system where swelling occurs upon ischemia-reperfusion injury. Our results suggest that receptors' function is finely modulated by their biophysical context, and specifically that osmotic swelling acts as a potentiator of downstream signaling, not only for the ß2-adrenergic receptor, but also for other receptors, hinting at a more general regulatory mechanism.

Integrating bioinformatics and ferroptosis to reveal the protective mechanism of Astragaloside IV on chronic heart failure rats.

Ferroptosis is an important pathological mechanism of chronic heart failure (CHF). This study aimed to investigate the protective mechanism of Astragaloside IV (AS-IV) on CHF rats by integrating bioinformatics and ferroptosis. CHF-related targets and ferroptosis-related targets were collected. After the intersection, the common targets were obtained. The PPI network of the common targets was constructed, and topological analysis of the network was carried out. The target with the highest topological parameter values was selected as the key target. The key target p53 was obtained through bioinformatics analysis, and its molecular docking model with AS-IV was obtained, as well as molecular dynamics simulation analysis. The rat models of CHF after myocardial infarction were established by ligation of left coronary artery and treated with AS-IV for 4 weeks. AS-IV treatment significantly improved cardiac function in CHF rats, improved cardiomyocyte morphology and myocardial fibrosis, reduced mitochondrial damage, decreased myocardial MDA and Fe2+ content, increased GSH content, inhibited the expression of p53 and p-p53, and up-regulated the expression of SLC7A11 and GPX4. In conclusion, AS-IV improved cardiac function in CHF rats, presumably by regulating p53/SLC7A11/GPX4 signaling pathway and inhibiting myocardial ferroptosis.

Engineered model of heart tissue repair for exploring fibrotic processes and therapeutic interventions.

Advancements in human-engineered heart tissue have enhanced the understanding of cardiac cellular alteration. Nevertheless, a human model simulating pathological remodeling following myocardial infarction for therapeutic development remains essential. Here we develop an engineered model of myocardial repair that replicates the phased remodeling process, including hypoxic stress, fibrosis, and electrophysiological dysfunction. Transcriptomic analysis identifies nine critical signaling pathways related to cellular fate transitions, leading to the evaluation of seventeen modulators for their therapeutic potential in a mini-repair model. A scoring system quantitatively evaluates the restoration of abnormal electrophysiology, demonstrating that the phased combination of TGFß inhibitor SB431542, Rho kinase inhibitor Y27632, and WNT activator CHIR99021 yields enhanced functional restoration compared to single factor treatments in both engineered and mouse myocardial infarction model. This engineered heart tissue repair model effectively captures the phased remodeling following myocardial infarction, providing a crucial platform for discovering therapeutic targets for ischemic heart disease.