Objective To investigate the impact of Astragaloside-IV (AS-IV) on the progression of myocardial infarction (MI) through macrophage-dependent mechanisms by regulating Snail1 lactylation and acetylation, as well as the transforming growth factor β (TGF-β) pathway. Methods Oxygen glucose deprivation (OGD) was used to establish an in vitro myocardial ischemia model in rat cardiomyocytes (H9c2), which were then treated with AS-IV. Cell viability was assessed using CCK-8, apoptosis was evaluated by flow cytometry, and LDH levels were measured to assess cellular damage. RAW246.7 cells were treated with LPS, and lactate levels in the supernatant were measured using ELISA, while expression of macrophage phenotype markers was evaluated using Western blot. RAW246.7 cell-conditioned medium (CM) was co-cultured with H9c2 cells to assess the protective effects of AS-IV on macrophage CM-mediated H9c2 damage. RAW246.7 cells were induced to differentiate into M1-like macrophages using LPS (100 ng/mL) + IFN-γ (20 ng/mL), and Snail1 was overexpressed in M1 macrophages. Transfected M1 macrophage CM was co-cultured with H9c2 cells to validate the mechanisms of AS-IV in MI. An MI rat model was established by ligation of the left anterior descending coronary artery (LAD), and was treated with AS-IV. Cardiac function, myocardial cell apoptosis, and cardiac tissue pathology were studied using echocardiography, TUNEL, and HE staining, respectively. Results Compared to the OGD group, AS-IV treatment promoted cell viability, reduced apoptosis and decreased LDH release. LPS upregulated lactate levels in the supernatant of RAW246.7 cell cultures and induced polarization of RAW246.7 cells to the M1 phenotype. AS-IV attenuated the damaging effects of RAW246.7 cell CM on H9c2 cells . Overexpression of Snail1 in M1 macrophages weakened the protective effects of AS-IV on H9c2 cells . In vivo study, results showed that, compared to the MI group, AS-IV treatment reduced lactate levels in the hearts of MI rats, improved cardiac function and myocardial injury and attenuated myocardial cell apoptosis. Conclusion AS-IV inhibits TGF-β pathway activation through the suppression of Snail1 lactylation and acetylation in a macrophage-dependent manner, thereby mitigating myocardial cell damage following MI.
Animals ; Myocardial Infarction/drug therapy* ; Rats ; Snail Family Transcription Factors/metabolism* ; Macrophages/cytology* ; Myocytes, Cardiac/metabolism* ; Triterpenes/pharmacology* ; Saponins/pharmacology* ; Acetylation/drug effects* ; Apoptosis/drug effects* ; Mice ; Cell Line ; RAW 264.7 Cells ; Transforming Growth Factor beta/metabolism*

Objective To investigate the effect of FUNDC1 tyrosine phosphorylation site mutations on mitophagy in H9c2 myocardial cells by constructing tyrosine site mutant plasmids (Y11 and Y18) of the FUN14 domain-containing protein 1 (FUNDC1). Methods The mutant plasmids constructed by whole-gene synthesis were transfected into rat myocardial H9c2 cells and divided into five groups: empty plasmid group, FUNDC1 overexpression group, Y11 mutant group, Y18 mutant group, and Y11 combined with Y18 mutant group. The viability of H9c2 cells was assessed using the CCK-8 assay. Additionally, tetramethylrhodamine ethyl ester (TMRE) staining was utilized to detect mitochondrial membrane potential. The protein expression levels of FUNDC1, translocase of the outer mitochondrial membrane 20 (TOM20), and cytochrome c oxidase IV (COX IV) were detected by Western blot analysis. Confocal microscopy was used to evaluate transfection efficiency as well as the co-localization of mitochondria and lysosomes. Results The FUNDC1 overexpression, Y11, Y18, and Y11 combined with Y18 mutant plasmids were successfully constructed. After plasmid transfection, widespread GFP fluorescence expression was observed under confocal microscopy. Compared with the empty plasmid group, FUNDC1 protein expression levels were significantly increased in the FUNDC1 overexpression group, Y11 mutation group, Y18 mutation group, and Y11 combined with Y18 mutation group, while cell viability and mitochondrial membrane potential showed no significant changes. Compared to the empty plasmid group, cells transfected with Y18 and Y11 combined with Y18 mutant plasmids showed increased TOM20 and COX IV expression levels and decreased mitochondrial-lysosomal co-localization. Conclusion Transfection with FUNDC1 Y18 or Y11 combined with Y18 mutant plasmids inhibited mitophagy in H9c2 myocardial cells.
Animals ; Rats ; Mitophagy/genetics* ; Myocytes, Cardiac/cytology* ; Mitochondrial Proteins/metabolism* ; Mutation ; Phosphorylation ; Tyrosine/genetics* ; Cell Line ; Membrane Proteins/metabolism* ; Membrane Potential, Mitochondrial

Astragali Radix (AR) and Notoginseng Radix et Rhizoma (NR) are frequently employed in cardiovascular disease treatment. However, the efficacy of the AR-NR medicine pair (AN) in improving cardiac remodeling and its underlying mechanism remains unclear. This study aimed to evaluate AN's cardioprotective effect and potential mechanism on cardiac remodeling using transverse aortic constriction (TAC) in mice and angiotensin II (Ang II)-induced neonatal rat cardiomyocytes (NRCMs) and fibroblasts in vitro. High-performance liquid chromatography-quadrupole-time of flight tandem mass spectrometry (HPLC-Q-TOF-MS/MS) characterized 23 main components of AN. AN significantly improved cardiac function in the TAC-induced mice. Furthermore, AN considerably reduced the serum levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP), cardiac troponin T (CTn-T), and interleukin-6 (IL-6) and mitigated inflammatory cell infiltration. Post-AN treatment, TAC-induced heart size approached normal. AN decreased cardiomyocyte cross-sectional area and attenuated the upregulation of cardiac hypertrophy marker genes (ANP, BNP, and MYH7) in vivo and in vitro. Concurrently, AN alleviated collagen deposition in TAC-induced mice. AN also reduced the expression of fibrosis-related indicators (COL1A1 and COL3A1) and inhibited the activation of the transforming growth factor-β1 (TGF-β1)/mothers against decapentaplegic homolog 3 (Smad3) pathway. Thus, AN improved TAC-induced cardiac remodeling. Moreover, AN downregulated p-dynamin-related protein (Drp1) (Ser616) expression and upregulated mitogen 2 (MFN-2) and optic atrophy 1 (OPA1) expression in vivo and in vitro, thereby restoring mitochondrial fusion and fission balance. In conclusion, AN improves cardiac remodeling by regulating mitochondrial dynamic balance, providing experimental data for the rational application of Chinese medicine prescriptions with AN as the main component in clinical practice.
Animals ; Drugs, Chinese Herbal/pharmacology* ; Myocytes, Cardiac/metabolism* ; Mice ; Rats ; Male ; Mitochondrial Dynamics/drug effects* ; Ventricular Remodeling/drug effects* ; Astragalus Plant/chemistry* ; Mice, Inbred C57BL ; Rhizome/chemistry* ; Panax notoginseng/chemistry* ; Rats, Sprague-Dawley ; Natriuretic Peptide, Brain/genetics* ; Humans ; Angiotensin II ; Astragalus propinquus

Zishen Huoxue decoction (ZSHX) enhances cardiomyocyte viability following hypoxic stress; however, its upstream therapeutic targets remain unclear. Network pharmacology and RNA sequencing analyses revealed that ZSHX target genes were closely associated with mitophagy and apoptosis in the mitochondrial pathway. In vitro, ZSHX inhibited pathological mitochondrial fission following hypoxic stress, regulated FUN14 domain-containing protein 1 (FUNDC1)-related mitophagy, and increased the levels of mitophagy lysosomes and microtubule-associated protein 1 light chain 3 beta II (LC3II)/translocase of outer mitochondrial membrane 20 (TOM20) expression while inhibiting the over-activated mitochondrial unfolded protein response. Additionally, ZSHX regulated the stability of beta-tubulin through Sirtuin 5 (SIRT5) and could modulate FUNDC1-related synergistic mechanisms of mitophagy and unfolded protein response in the mitochondria (UPR^mt) via the SIRT5 and -β-tubulin axis. This targeting pathway may be crucial for cardiomyocytes to resist hypoxia. Collectively, these findings suggest that ZSHX can protect against cardiomyocyte injury via the SIRT5-β-tubulin axis, which may be associated with the synergistic protective mechanism of SIRT5-β-tubulin axis-related mitophagy and UPR^mt on cardiomyocytes.
Mitophagy/drug effects* ; Tubulin/genetics* ; Animals ; Myocytes, Cardiac/metabolism* ; Drugs, Chinese Herbal/pharmacology* ; Sirtuins/genetics* ; Unfolded Protein Response/drug effects* ; Myocardial Ischemia/genetics* ; Rats ; Humans ; Rats, Sprague-Dawley ; Apoptosis/drug effects* ; Male

Astragali Radix (AR), a traditional Chinese medicine (TCM), has demonstrated therapeutic efficacy against various diseases, including cardiovascular conditions, over centuries of use. While doxorubicin serves as an effective chemotherapeutic agent against multiple cancers, its clinical application remains constrained by significant cardiotoxicity. Research has indicated that AR exhibits protective properties against doxorubicin-induced cardiomyopathy (DIC); however, the specific bioactive components and underlying mechanisms responsible for this therapeutic effect remain incompletely understood. This investigation seeks to identify the protective bioactive components in AR against DIC and elucidate their mechanisms of action. Through network medicine analysis, astragaloside IV (AsIV) and formononetin (FMT) were identified as potential cardioprotective agents from 129 AR components. In vitro experiments using H9c2 rat cardiomyocytes revealed that the AsIV-FMT combination (AFC) effectively reduced doxorubicin-induced cell death in a dose-dependent manner, with optimal efficacy at a 1∶2 ratio. In vivo, AFC enhanced survival rates and improved cardiac function in both acute and chronic DIC mouse models. Additionally, AFC demonstrated cardiac protection while maintaining doxorubicin's anti-cancer efficacy in a breast cancer mouse model. Lipidomic and metabolomics analyses revealed that AFC normalized doxorubicin-induced lipid profile alterations, particularly by reducing fatty acid accumulation. Gene knockdown studies and inhibitor experiments in H9c2 cells demonstrated that AsIV and FMT upregulated peroxisome proliferator activated receptor γ coactivator 1α (PGC-1α) and PPARα, respectively, two key proteins involved in fatty acid metabolism. This research establishes AFC as a promising therapeutic approach for DIC, highlighting the significance of multi-target therapies derived from natural herbals in contemporary medicine.
Animals ; Doxorubicin/adverse effects* ; Saponins/administration & dosage* ; Isoflavones/pharmacology* ; Rats ; Cardiomyopathies/prevention & control* ; Mice ; Fatty Acids/metabolism* ; Myocytes, Cardiac/metabolism* ; Triterpenes/administration & dosage* ; Male ; Drugs, Chinese Herbal/administration & dosage* ; Humans ; Cardiotonic Agents/administration & dosage* ; Mice, Inbred C57BL ; Cell Line ; Astragalus Plant/chemistry* ; Astragalus propinquus

OBJECTIVE: To explore the molecular mechanism of Shenmai Injection (SMI) against doxorubicin (DOX) induced cardiomyocyte apoptosis. METHODS: A total of 40 specific pathogen-free (SPF) male Sprague Dawley (SD) male rats were divided into 5 groups based on the random number table, including the control group, the model group, miR-30a agomir group, SMI low-dose (SMI-L) group, and SMI high-dose (SMI-H) group, with 8 rats in each group. Except for the control group, the rats were injected weekly with DOX (2 mg/kg) in the tail vein for 4 weeks to induce myocardial injury, and were given different regimens of continuous intervention for 2 weeks. Cardiac function was detected by echocardiography and myocardial pathological changes were observed by Van Gieson (VG) staining. Myocardial injury serum markers, including creatine kinase (CK), lactate dehydrogenase (LDH), troponin T (cTnT), N-terminal pro-brain natriuretic peptide (NT-proBNP), soluble ST2 (sST2), and growth differentiation factor-15 (GDF-15) were detected by enzyme linked immunosorbent assay (ELISA). Cardiomyocyte apoptosis was observed by terminal deoxynucleotidyl transferase-mediated biotinylated dUTP triphosphate nick end labeling (TUNEL) and transmission electron microscopy, and the expressions of target proteins and mRNA were detected by Western blot and quantitative real time polymerase chain reaction (qRT-RCR), respectively. RESULTS: The treatment with different doses of SMI reduced rat heart mass index and left ventricular mass index (P<0.05), significantly improved the left ventricular ejection fraction (P<0.05), decreased the levels of serum CK, LDH, cTnT, and NT-proBNP (P<0.05 or P<0.01), reduced the levels of serum sST2 and GDF-15 (P<0.05 or P<0.01), decreased the collagen volume fraction, reduced the expressions of rat myocardial type I and type III collagen (P<0.05 or P<0.01), and effectively alleviated myocardial fibrosis. And the study found that SMI promoted the expression levels of miR-30a and Bcl-2 in myocardium, and down-regulated the expression of Bax, which inhibited the activation of Caspase-3 and Caspase-9 (P<0.05 or P<0.01), and improved myocardial cell apoptosis. CONCLUSIONS SMI can alleviate myocardial injury and apoptosis caused by DOX, and its mechanism possibly by promoting the targeted expression of myocardial Bcl-2 protein through miR-30a.
Animals ; Myocytes, Cardiac/metabolism* ; Apoptosis/drug effects* ; MicroRNAs/genetics* ; Rats, Sprague-Dawley ; Male ; Drugs, Chinese Herbal/administration & dosage* ; Doxorubicin/pharmacology* ; Proto-Oncogene Proteins c-bcl-2/genetics* ; Drug Combinations ; Injections ; Rats

OBJECTIVES: To investigate the mechanism through which N-acetylneuraminic acid (Neu5Ac) exacerbates hypoxia/reoxygenation (H/R) injury in rat cardiomyocytes (H9C2 cells). METHODS: H9C2 cells were cultured in hypoxia and glucose deprivation for 8 h followed by reoxygenation for different durations to determine the optimal reoxygenation time. Under the optimal H/R protocol, the cells were treated with 0, 5, 10, 20, 30, 40, 50, and 60 mmol/L Neu5Ac during reoxygenation to explore the optimal drug concentration. The cells were then subjected to H/R injury followed by treatment with Neu5Ac, Fer-1 (a ferroptosis inhibitor), or both. The changes in SOD activity, intracellular Fe²⁺ and lipid ROS levels in the cells were evaluated, and the cellular expressions of Nrf2, GPX4, HO-1, FSP1, and xCT proteins were detected using Western blotting. RESULTS: Following hypoxia and glucose deprivation for 8 h, the cells with reoxygenation for 6 h, as compared with other time lengths of reoxygenation except for 9 h, showed the lowest expression levels of Nrf2, GPX4, HO-1, and FSP1 proteins (P<0.001). Neu5Ac treatment of dose-dependently decreased the viability of the cells with H/R injury with an IC₅₀ of 30.07 mmol/L. Reoxygenation for 3 h with normal glucose supplementation and a Neu5Ac concentration of 30 mmol/L were selected as the optimal conditions in the subsequent experiments. The results showed that Neu5Ac could significantly increase SOD activity, Fe²⁺ and lipid ROS levels and reduce Nrf2, GPX4, HO-1, and FSP1 protein expressions in H9C2 cells with H/R injury, but its effects were significantly attenuated by treatment with Fer-1. CONCLUSIONS Neu5Ac exacerbates ferroptosis of myocardial cells with H/R injury by inhibiting the Nrf2 axis to promote the production of ROS and lipid ROS.
Ferroptosis/drug effects* ; Myocytes, Cardiac/cytology* ; Animals ; NF-E2-Related Factor 2/metabolism* ; Rats ; N-Acetylneuraminic Acid/pharmacology* ; Cell Hypoxia ; Reactive Oxygen Species/metabolism* ; Cell Line ; Myocardial Reperfusion Injury/metabolism*

OBJECTIVES: To explore the mechanism that mediate the therapeutic effect of quercetin on heart failure. METHODS: We searched the TCMSP and Swiss ADME databases for the therapeutic targets of quercetin and retrieved heart failure targets from the Genecards and OMIM databases. The intersecting targets were analyzed with GO and KEGG pathway analysis using DAVID database, and the key genes were identified via PPI analysis. Molecular docking between the core targets and quercetin was performed using PyMOL and AutoDock Tools. In a heart failure model established in H9C2 cardiomyocytes by treatment with isoproterenol, the effect of quercetin on the expressions of the MAPK signaling pathway was tested. RESULTS: A total of 60 intersecting targets were identified. Enrichment analysis revealed that quercetin may inhibit heart failure through the MAPK signaling pathway. The core genes, including AMPK3 and BCL-2, were identified as potential key regulators in quercetin-mediated improvement of heart failure. Cellular experiments demonstrated that quercetin significantly reduced isoproterenol-induced apoptosis of cardiomyocytes in a dose-dependent manner and obviously decreased the Bax/Bcl-2 ratio and the expression levels of caspase-3, ERK and p38 in the cells. CONCLUSIONS Quercetin improves heart failure possibly by inhibiting cardiomyocyte apoptosis through the MAPK signaling pathway.
Quercetin/pharmacology* ; Myocytes, Cardiac/drug effects* ; Heart Failure/metabolism* ; Apoptosis/drug effects* ; MAP Kinase Signaling System/drug effects* ; Rats ; Animals ; Isoproterenol

OBJECTIVES: To investigate the effects of quercetin on cuproptosis and L-type calcium currents in the myocardium of diabetic rats. METHODS: Forty SD rats were randomized into control group and diabetic model groups. The rat models of diabetes mellitus (DM) induced by high-fat and high-sugar diet combined with streptozotocin (STZ) injection were further divided into DM model group, quercetin treatment group, and empagliflozin treatment group (n=10). Blood glucose and body weight were measured every other week, and cardiac function of the rats was evaluated using echocardiography. HE staining, Sirius red staining, and wheat germ agglutinin (WGA) analysis were used to observe the changes in myocardial histomorphology, and serum copper levels and myocardial FDX1 expression were detected. In cultured rat cardiomyocyte H9c2 cells with high-glucose exposure, the effects of quercetin and elesclomol, alone or in combination, on intracellular CK-MB and LDH levels and FDX1 expression were assessed, and the changes in L-type calcium currents were analyzed using patch-clamp technique. RESULTS: The diabetic rats exhibited elevated blood glucose, reduced body weight, impaired left ventricular function, increased serum copper levels and myocardial FDX1 expression, decreased L-type calcium currents, and prolonged action potential duration. Quercetin and empagliflozin treatment significantly lowered blood glucose, improved body weight, and restored cardiac function of the diabetic rats, and compared with empagliflozin, quercetin more effectively reduced serum copper levels, downregulated FDX1 expression, and enhanced myocardial L-type calcium currents in diabetic rats. In H9c2 cells, high glucose exposure significantly increased myocardial expressions of FDX1, CK-MB and LDH, which were effectively lowered by quercetin treatment; Elesclomol further elevated FDX1, CK-MB and LDH levels in the exposed cells, and these changes were not significantly affected by the application of quercetin. CONCLUSIONS Quercetin ameliorates myocardial injury in diabetic rats possibly by suppressing myocardial cuproptosis signaling and restoring L-type calcium channel activity.
Animals ; Quercetin/pharmacology* ; Calcium Channels, L-Type/metabolism* ; Diabetes Mellitus, Experimental/metabolism* ; Rats, Sprague-Dawley ; Rats ; Myocytes, Cardiac/drug effects* ; Myocardium/pathology* ; Male

OBJECTIVES: To explore the mechanism of Circ-MYOCD back-splicing and its regulatory role in myocardial hypertrophy. METHODS: Sanger sequencing and RNase R assays were performed to verify the circularity and stability of Circ-MYOCD, whose subcellular distribution was determined by nuclear-cytoplasmic fractionation. Bioinformatics analysis and mass spectrometry from pull-down assays were conducted to predict the RNA-binding proteins (RBPs) interacting with Circ-MYOCD. In rat cardiomyocytes H9C2 cells, the effects of HNRNPH1 and HNRNPL knockdown and overexpression on Circ-MYOCD back-splicing were evaluated. In a H9C2 cell model of angiotensin II (Ang II)-induced myocardial hypertrophy, the expression of HNRNPH1 was detected, the effects of HNRNPH1 knockdown and overexpression on progression of myocardial hypertrophy were assessed, and the regulatory effect of HNRNPH1 on Circ-MYOCD back-splicing was analyzed. RESULTS: Sanger sequencing confirmed that the junction primers could amplify the correct Circ-MYOCD sequence. RNase R and nuclear-cytoplasmic fractionation assays showed that Circ-MYOCD was stable and predominantly localized in the cytoplasm. Bioinformatics analysis and mass spectrometry from the Circ-MYOCD pull-down assay identified HNRNPH1 and HNRNPL as the RBPs interacting with Circ-MYOCD. In H9C2 cells, HNRNPH1 knockdown significantly enhanced while its overexpression inhibited Circ-MYOCD back-splicing; HNRNPH1 overexpression obviously increased the expressions of myocardial hypertrophy markers ANP and BNP, while its knockdown produced the opposite effect. In Ang II-induced H9C2 cells, which exhibited a significant increase of HNRNPH1 expression and increased expressions of ANP and BNP, HNRNPH1 knockdown obviously increased Circ-MYOCD expression, decreased MYOCD expression and lowered both ANP and BNP expressions. CONCLUSIONS HNRNPH1 regulates Circ-MYOCD back-splicing to influence the progression of myocardial hypertrophy.
Animals ; Rats ; RNA, Circular/genetics* ; Cardiomegaly/metabolism* ; Myocytes, Cardiac/metabolism* ; Heterogeneous-Nuclear Ribonucleoprotein Group F-H/metabolism* ; Cell Line ; RNA Splicing ; Angiotensin II ; RNA-Binding Proteins