Quercetin Improves Cardiomyocyte Vulnerability to Hypoxia by Regulating SIRT1/TMBIM6-Related Mitophagy and Endoplasmic Reticulum Stress

Dynamic and quantitative assessment of quercetin for cardiac oxidative stress injury prevention using sensitive cardiomyocyte based biosensing

Myocardial infarction is a leading cause of morbidity and mortality associated with cardiovascular diseases worldwide. Although novel medications and treatments greatly alleviate patient suffering, challenges related to prognostic limit the recovery of cardiac function. Currently, treatment with monomeric compounds displays promise in prognostic interventions for cardiac diseases. However, there is a lack of dynamic and quantitative assessment of cardiomyocyte response to these drugs. Herein, an integrated biosensing platform with a microelectrode array was constructed for label-free, non-invasive, long-term, and real-time recording of cardiomyocyte electrophysiological signals. By analyzing the signals of cardiomyocytes before and after treatment, we established the safe concentration of quercetin in cardiomyocytes and identified its long-term cardiotoxicity. Moreover, quercetin also demonstrated significant protective effects on cardiomyocytes in a H2O2-induced oxidative stress injury model. This study provides a trustworthy platform to evaluate the effects of monomeric compounds on cardiomyocytes, and offers a novel approach for drug screening and efficacy testing in cardiovascular diseases.

Parkin modulates the hepatocellular carcinoma microenvironment by regulating PD-1/PD-L1 signalling

INTRODUCTION

Parkin-mediated mitophagy is essential for clearing damaged mitochondria, and it inhibits tumour development. The role of mitophagy in modulating tumour immunity is becoming clearer, but the underlying mechanism is still poorly understood.

OBJECTIVE

This study was designed to examine the role of Parkin in the immune microenvironment of liver tumours induced by carbon tetrachloride (CCl4).

METHODS

Single-cell RNA sequencing analysis, Western blot, immunofluorescence and co-immunoprecipitation were used to verify the mechanism of Parkin affecting the tumour microenvironment by altering the expression of PD-1.

RESULTS

Our data revealed that Park2-/- mice showed severe liver damage and increased malignancy. Single-cell RNA sequencing analysis of T lymphocytes in liver tumours showed that the number of cytotoxic CD8+ T cells (Gzmb/Ifng/Fasl) was significantly decreased and the number of exhausted CD8+ T cells (Pdcd1/Lag3/Tigit/Havcr2/Ctla4) was significantly increased in Park2-/- mice, indicating the immune suppressive microenvironment. Single-cell RNA sequencing analysis of myeloid-derived cells also displayed the increase of M2-like macrophages in Park2-/- mice. Through quantitative proteomic analysis, it was found that the differential protein expression between the two groups mainly localized in the plasma membrane and extracellular, including PD-1, MHC-Ⅰ molecules etc., and was mainly associated with PD-1 and antigen presentation pathways. It could impair the antitumour immune response with Parkin deficiency. Parkin deficiency leads to the decrease of hepatic mitophagy levels and the formation of an immune suppressive microenvironment, which promotes the tumourigenesis of liver cancer.

CONCLUSION

As an E3 ubiquitin ligase, Parkin induces the ubiquitination and degradation of PD-1 in liver cancer and could influence antitumour immunity through the PD-1/PD-L1 signalling pathway. Thus, remodeling the tumour microenvironment through the reintroduction of Parkin or enhancement of mitophagy could activate the anti-tumour immune response and improve the immunotherapy efficacy, which may be a promising strategy for the treatment of HCC.

Quercetin Alleviates Hyperglycemic-Generated Endoplasmic Reticulum Stress-Contacted Apoptosis of Rat Nucleus Pulposus Cells

Background

Previous research has shown that apoptosis of nucleus pulposus (NP) cells contributes to intervertebral disc degeneration (IDD) progression. Endoplasmic reticulum (ER) stress is a reaction to diverse stimuli in eukaryotes and is tightly contacted with apoptosis. Quercetin, a naturally occurring flavonoid, exerts protective effects against degenerative diseases via ER stress. However, the effect of quercetin on NP cell apoptosis remains unclear.

Aims

To investigate the influences of quercetin on apoptosis and ER stress in a high-glucose-generated primary NP cell model.

Study Design

In vivo animal experimental study.

Methods

To investigate the influence of quercetin in a high-glucose-generated NP cell apoptosis model, control, glucose, and glucose + quercetin groups adopted with Sprague-Dawley rats primary NP cells. In the glucose group, cell apoptosis was generated by 200 mm high glucose. In the glucose + quercetin group, 60 μm quercetin was pretreated with NP cells for 2 h before glucose administration. In this research, we examined the change effect of quercetin on NP cell apoptosis, ER stress, and the protein kinase R-like ER kinase (PERK)-eukaryotic translation initiation element 2α (eIF2α)-activating transcription element 4 (ATF4).

Results

High glucose decreased the viability and induced ER stress-related apoptosis in NP cells. Quercetin modulated ER stress through the PERK-eIF2α-ATF4 pathway, thereby alleviating the apoptosis rank in NP cells.

Conclusion

Quercetin exerts antiapoptotic effects on NP cells, probably through ER stress, thereby showcasing potential as a therapeutic method for treating IDD.

Quercetin inhibits mitophagy-mediated apoptosis and inflammatory response by targeting the PPARγ/PGC-1α/NF-κB axis to improve acute liver failure

BACKGROUND

Reactive oxygen species (ROS) from mitochondrial dysfunction are critical in triggering apoptosis and inflammation in acute liver failure (ALF). Quercetin (QUE), an antioxidant, is renowned for its therapeutic effects onliverdiseases. There are no studies on whether QUE regulates mitophagy level in hepatocytes to inhibit ALF.

OBJECTIVE

This study investigates QUE's protective effects on ALF and elucidates the mechanisms involved.

METHODS

The ALF and hepatocyte inflammatory injury model was established using LPS and D-Galn. To predict potential targets and mechanisms of QUE in ALF treatment, transcriptomics, network pharmacology, molecular docking techniques, and ChIP were employed. The expression level related to mitophagy, apoptosis, and signaling pathways were detected by CCK8, IHC, IF staining, TUNEL, RT-qPCR, TEM, Western blotting, ELISA, and flow cytometry.

RESULTS

Network pharmacology and transcriptomics revealed common targets between QUE and ALF. Enrichment analysis showed that the anti-ALF targets of QUE were significantly associated with mitochondria and NF-κB-related pathways. Subsequent experiments showed that QUE pretreatment significantly alleviated the loss of hepatocyte viability, enhanced mitochondrial membrane potential, activated mitophagy, and promoted the clearance of damaged mitochondria, thereby reducing ROS accumulation, significantly reducing cell apoptosis and inflammatory responses, reducing ALT and AST levels, and improving liver tissue pathology. Mechanistically, molecular docking, DARTS, and CETSA analyses confirmed that QUE directly binds to the PPARγ molecule, which reduced binding to IκB and significantly inhibit the NF-κB pathway to exert its protective effects.

CONCLUSION

In short, our results provide the first evidence that QUE improves acute liver failure by promoting mitophagy through regulating the PPARγ/PGC-1α/NF-κB axis and inhibiting apoptosis and inflammatory responses mediated by mitochondrial dysfunction, which provides evidence for the potential of QUE in the treatment of ALF.

Quercetin preserves mitochondria-endoplasmic reticulum contact sites improving mitochondrial dynamics in aged myocardial cells

Cardiomyocyte senescence plays a crucial role in the pathophysiology of age-related cardiovascular disease. Senescent cells with impaired contractility, mitochondrial dysfunction, and hypertrophic growth accumulate in the heart during aging, contributing to cardiac dysfunction and remodeling. Mitochondrial dynamics is altered in aging cells, leading to changes in their function and morphology. Such rearrangements can affect the spatially restricted region of the mitochondrial membrane that interacts with reticulum membrane fragments, termed mitochondria-endoplasmic reticulum (ER) contact sites (MERCs). Besides, oxidative stress associated with inefficient organelle turnover can drive cellular senescence. Therefore, in this study, we evaluated the possible association between the senolytic effect of the antioxidant quercetin (Q) and MERCs preservation in a D-galactose-induced cellular senescence model. We found that Q ameliorates the senescent phenotype of H9c2 cells in association with increased mitochondria-ER colocalization, reduced distance between both organelles, and lower ROS production. Moreover, regulation of fusion and fission processes was related with increased mitochondrial ATP production and enhanced transmembrane potential. Overall, our data provide evidence that the inhibitory effect of Q on cellular senescence is associated with preserved MERCs and improved mitochondrial function and morphology, which might contribute to the attenuation of cardiac dysfunction.

Quercetin Alleviates Cardiac Fibrosis via Regulating the SIRT3 Signaling Pathway

PURPOSE

Cardiovascular diseases, exacerbated by cardiac fibrosis, are the leading causes of mortality. We aimed to determine the role of quercetin (QU) in cardiac fibrosis and the underlying mechanism.

METHODS

In this study, 8-week-old mice were subjected to either transverse aortic constriction (TAC) or sham surgery, then they were administered QU or saline. Thereafter, cardiac function and cardiac hypertrophy were accessed. In vitro, cardiac fibroblasts (CFs) were treated with angiotensin II (Ang II) with or without QU. Western blot, qPCR, EdU incorporation assay, and immunofluorescence staining analysis were used to investigate the molecular and cellular features.

RESULTS

For the TAC mouse model, cardiac fibrosis was alleviated by QU. The study revealed that the trans-differentiation and proliferation of CFs promoted by Ang II would be reversed by QU in vitro. Mechanistically, QU exerted the anti-fibrotic effect by regulating the SIRT3/TGF-β/Smad3 signaling pathway.

CONCLUSION

Quercetin protects against cardiac fibrosis by mediating the SIRT3 signaling pathway.

Astragaloside IV alleviates septic myocardial injury through DUSP1-Prohibitin 2 mediated mitochondrial quality control and ER-autophagy

INTRODUCTION

Septic cardiomyopathy (SCM) is a complication of myocardial injury in patients with severe sepsis.

OBJECTIVES

This study highlights the potential of Astragaloside IV(AS) in the treatment of septic cardiomyopathy and provides a reference for developing cardioprotective drugs targeting DUSP1-PHB2-related mitochondria-ER interaction.

METHODS

Dual specificity phosphatase-1 (DUSP1)/Prohibitin 2 cardiomyocyte-specific knockout mice (DUSP1/PHB2CKO) /DUSP1 transgenic mice (DUSP1/PHB2TG) were used to generate LPS-induced sepsis models. The pathological mechanism by which AS-IV improves heart injury was detected using cardiac ultrasound, fluorescence staining, transmission electron microscopy, and western blotting. After siRNA treatment of cardiomyocytes with DUSP-1/PHB2, changes in mitochondrial function and morphology were determined using qPCR, western blotting, ELISA, and laser confocal microscopy, and the targeted therapeutic effects of AS-IV were further examined.

RESULTS

SCM treatment leads to severe mitochondrial dysfunction. However, Astragaloside IV (AS) treatment normalizes mitochondrial homeostasis and ER function. Notably, the protective effect was blocked in DUSP1/Prohibitin 2 cardiomyocyte-specific knockout mice (DUSP1/PHB2CKO) but remained unaffected in DUSP1 transgenic mice (DUSP1/PHB2TG).

CONCLUSION

This study highlights the potential of AS in the treatment of septic cardiomyopathy and provides a reference for developing cardioprotective drugs targeting DUSP1-PHB2 related mitochondria-ER interaction.

Potential of natural drug modulation of endoplasmic reticulum stress in the treatment of myocardial injury

Myocardial injury (MI) is a common occurrence in clinical practice caused by various factors such as ischemia, hypoxia, infection, metabolic abnormalities, and inflammation. Such damages are characterized by a reduction in myocardial function and cardiomyocyte death that can result in dangerous outcomes such as cardiac failure and arrhythmias. An endoplasmic reticulum stress (ERS)-induced unfolded protein response (UPR) is triggered by several stressors, and its intricate signaling networks are instrumental in both cell survival and death. Cardiac damage frequently triggers ERS in response to different types of injuries and stress. High levels of ERS can exacerbate myocardial damage by inducing necrosis and apoptosis. To target ERS in MI prevention and treatment, current medical research is focused on identifying effective therapy approaches. Traditional Chinese medicine (TCM) is frequently used because of its vast range of applications and low risk of adverse effects. Various studies have demonstrated that active components of Chinese medicines, including polyphenols, saponins, and alkaloids, can reduce myocardial cell death, inflammation, and modify the ERS pathway, thus preventing and mitigating cardiac injury. Thus, this paper aims to provide a new direction and scientific basis for targeting ERS in MI prevention and treatment. We specifically summarize recent research progress on the regulation mechanism of ERS in MI by active ingredients of TCM.

Ginsenoside Rb1 ameliorates heart failure through DUSP-1-TMBIM-6-mediated mitochondrial quality control and gut flora interactions

BACKGROUND

There is currently no specific therapeutic drug available for heart failure in clinical practice. Numerous studies have validated the efficacy of Ginsenoside Rb1, an active component found in various herbal remedies used for heart failure treatment, in effectively ameliorating myocardial ischemia. However, the precise mechanism of action and molecular targets of Ginsenoside Rb1 remain unclear.

PURPOSE

This study aims to explore the molecular mechanisms through which Ginsenoside Rb1 synergistically modulates the gut flora and mitochondrial quality control network in heart failure by targeting the DUSP-1-TMBIM-6-VDAC1 axis.

STUDY DESIGN

This study utilized DUSP-1/VDAC1 knockout (DUSP-1-/-/VDAC1-/-) and DUSP-1/VDAC1 transgenic (DUSP-1+/+/VDAC1+/+) mouse models of heart failure, established through Transverse Aortic Constriction (TAC) surgery and genetic modification techniques. The mice were subsequently subjected to treatment with Ginsenoside Rb1.

METHODS

A series of follow-up multi-omics analyses were conducted, including assessments of intestinal flora, gene transcription sequencing, single-cell databases, and molecular biology assays of primary cardiomyocytes, to investigate the mechanism of action of Ginsenoside Rb1.

RESULTS

Ginsenoside Rb1 was found to have multiple regulatory mechanisms on mitochondria. Notably, DUSP-1 was discovered to be a crucial molecular target of Ginsenoside Rb1, controlling both intestinal flora and mitochondrial function. The regulatory effects of DUSP-1 on inflammation and mitochondrial quality control were mediated by changes in TMBIM-6 and VDAC1. Furthermore, NLRP3-mediated inflammatory responses were found to interact with mitochondrial quality control, exacerbating myocardial injury under stress conditions. Ginsenoside Rb1 modulated the DUSP-1-TMBIM-6-VDAC1 axis, inhibited the release of pro-inflammatory factors, altered the structural composition of the gut flora, and protected impaired heart function. These effects indirectly influenced the crosstalk between inflammation, mitochondria, and gut flora.

CONCLUSION

The DUSP-1-TMBIM-6-VDAC1 axis, an upstream pathway regulated by Ginsenoside Rb1, is a profound mechanism through which Ginsenoside Rb1 improves cardiac function in heart failure by modulating inflammation, mitochondria, and gut flora.

Zishenhuoxue decoction-induced myocardial protection against ischemic injury through TMBIM6-VDAC1-mediated regulation of calcium homeostasis and mitochondrial quality surveillance

BACKGROUND

Zishenhuoxue decoction (ZSHX), a Chinese herbal medicine, exhibits myocardial and vascular endothelial protective properties. The intricate regulatory mechanisms underlying myocardial ischemic injury and its association with dysfunctional mitochondrial quality surveillance (MQS) remain elusive.

HYPOTHESIS/PURPOSE

To study the protective effect of ZSHX on ischemic myocardial injury in mice using a TMBIM6 gene-modified animal model and mitochondrial quality control-related experiments.

STUDY DESIGN

Using model animals and myocardial infarction surgery-induced ischemic myocardial injury TMBIM6 gene-modified mouse models, the pharmacological activity of ZSHX in inhibiting ischemic myocardial injury and mitochondrial homeostasis disorder in vivo was tested.

METHODS

Our focal point entailed scrutinizing the impact of ZSHX on ischemic myocardial impairment through the prism of TMBIM6. This endeavor was undertaken utilizing mice characterized by heart-specific TMBIM6 knockout (TMBIM6CKO) and their counterparts, the TMBIM6 transgenic (TMBIM6TG) and VDAC1 transgenic (VDAC1TG) mice.

RESULTS

ZSHX demonstrated dose-dependent effectiveness in mitigating ischemic myocardial injury and enhancing mitochondrial integrity. TMBIM6CKO hindered ZSHX's cardio-therapeutic and mitochondrial protective effects, while ZSHX's benefits persisted in TMBIM6TG mice. TMBIM6CKO also blocked ZSHX's regulation of mitochondrial function in HR-treated cardiomyocytes. Hypoxia disrupted the MQS in cardiomyocytes, including calcium overload, excessive fission, mitophagy issues, and disrupted biosynthesis. ZSHX counteracted these effects, thereby normalizing MQS and inhibiting calcium overload and cardiomyocyte necroptosis. Our results also showed that hypoxia-induced TMBIM6 blockade resulted in the over-activation of VDAC1, a major mitochondrial calcium uptake pathway, while ZSHX could increase the expression of TMBIM6 and inhibit VDAC1-mediated calcium overload and MQS abnormalities.

CONCLUSIONS

Our findings suggest that ZSHX regulates mitochondrial calcium homeostasis and MQS abnormalities through a TMBIM6-VDAC1 interaction mechanism, which helps to treat ischemic myocardial injury and provides myocardial protection. This study also offers insights for the clinical translation and application of mitochondrial-targeted drugs in cardiomyocytess.

Uncovering the action mechanism of Shenqi Tiaoshen formula in the treatment of chronic obstructive pulmonary disease through network pharmacology, molecular docking, and experimental verification

OBJECTIVE

To reveal the potential underlying mechanism of the Shenqi Tiaoshen formula (, SQTS) in the treatment of chronic obstructive pulmonary disease (COPD) by utilizing network pharmacology, molecular docking, and experimental verification.

METHODS

Multiple open-source databases and research related to Traditional Chinese Medicine or compounds were employed to screen active ingredients and corresponding potential targets of the SQTS. The protein-protein interaction network screened hub genes, the relevant molecular mechanism and gene regulation were initially identified through the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analysis, and molecular docking was used to confirm further the interaction of the main components bound to the core targets. In vivo experiments on the COPD combined Qi-deficiency syndrome rat model were performed to verify the intervention effects and predicted potential molecular mechanisms of the SQTS.

RESULTS

This study selected 156 active compounds and 326 candidate targets for treating COPD. Quercetin, Nobiletin, Kaempferol, Luteolin, Ginsenoside Rh2 and Formononetin were probably the main active compounds of SQTS in COPD treatment as they affected the most COPD-related targets, and interleukin-1 (IL-6), signal transducing activator of transcription 3 (STAT3), matrix metalloproteinase-9 (MMP9), vascular endothelial growth factor A (VEGFA), protein kinase B (AKT1), hypoxia-inducible factor-1α (HIF-1α), and forkhead box O3 (FoxO3) were identified as the hub genes associated with its therapeutic effect. KEGG analysis was mainly enriched in the signaling pathways closely related to inflammation, immunity and oxidative stress, such as HIF-1, tumor necrosis factor (TNF), phosphatidylinositol 3 kinase (PI3K)-AKT, FoxO, apoptosis, IL-17, and toll-like receptor. Molecular docking confirmed that the main active components shared a good affinity with the hub genes. In vivo experiments, the SQTS was found to improve the body weight, exhaustive swimming time, tail-hanging immobility time and struggle times, airway inflammation, lung functions, and inflammatory factors in the rat model of COPD. The up-regulation of p-PI3K, p-AKT, HIF-1α, FoxO3α, toll like receptor 4, VEGFA, Caspase 3, TNF-α, and IL-17 in COPD rats were down-regulated by SQTS, consistent with the network pharmacology results.

CONCLUSIONS

This study provides evidence that the SQTS plays a critical role in anti-inflammation via suppressing immune inflammation and oxidative stress related pathways, indicating that the SQTS is a candidate herbal drug for further investigation in treating COPD.

Amplification of Cardioprotective Response of Remote Ischemic Preconditioning in Rats by Quercetin: Potential Role of Activation of mTOR-dependent Autophagy and Nrf2

OBJECTIVES

Noninvasive remote ischemic preconditioning (RIPC) is a practical, acceptable, and feasible conditioning technique reported to provide cardioprotection in myocardial ischemia-reperfusion injury (MIRI). It has been well-reported that quercetin possesses antioxidant and anti-inflammatory properties. This study investigates the modification of the cardioprotective response of RIPC by quercetin.

METHODS

Adult Wistar rats were randomized into 12 groups of six animals each. MIRI was induced by subjecting the isolated hearts of Wistar rats to global ischemia for 30 min, succeeded by reperfusion of 120 min after mounting on the Langendorff PowerLab apparatus. Hind limb RIPC was applied in four alternate cycles of ischemia and reperfusion of 5 min each by tying the pressure cuff before isolation of hearts.

RESULTS

MIRI was reflected by significantly increased infarct size, LDH-1, and CK-MB, TNF-α, TBARS, and decreased GSH, catalase, and hemodynamic index, and modulated Nrf2. Pretreatment of quercetin (25 and 50 mg/kg; i.p.) significantly attenuated the MIRI-induced cardiac damage and potentiated the cardioprotective response of RIPC at the low dose. Pretreatment of ketamine (10 mg/kg; i.p.), an mTOR-dependent autophagy inhibitor, significantly abolished the cardioprotective effects of quercetin and RIPC.

CONCLUSIONS

The findings highlight the modification of the cardioprotective effect of RIPC by quercetin and that quercetin protects the heart against MIRI through multiple mechanisms, including mTOR-dependent activation of autophagy and Nrf-2 activation.

Cardiovascular protection of YiyiFuzi powder and the potential mechanisms through modulating mitochondria-endoplasmic reticulum interactions

Cardiovascular diseases (CVD) remain the leading cause of death worldwide and represent a major public health challenge. YiyiFuzi Powder (YYFZ), composed of Coicis semen and Fuzi, is a classical traditional Chinese medicine prescription from the Synopsis of Golden Chamber dating back to the Han Dynasty. Historically, YYFZ has been used to treat various CVD, rooted in Chinese therapeutic principles. Network pharmacology analysis indicated that YYFZ may exhibit direct or indirect effects on mitochondria-endoplasmic reticulum (ER) interactions. This review, focusing on the cardiovascular protective effects of Coicis semen and Fuzi, summarizes the potential mechanisms by which YYFZ acts on mitochondria and the ER. The underlying mechanisms are associated with regulating cardiovascular risk factors (such as blood lipids and glucose), impacting mitochondrial structure and function, modulating ER stress, inhibiting oxidative stress, suppressing inflammatory responses, regulating cellular apoptosis, and maintaining calcium ion balance. The involved pathways include, but were not limited to, upregulating the IGF-1/PI3K/AKT, cAMP/PKA, eNOS/NO/cGMP/SIRT1, SIRT1/PGC-1α, Klotho/SIRT1, OXPHOS/ATP, PPARα/PGC-1α/SIRT3, AMPK/JNK, PTEN/PI3K/AKT, β2-AR/PI3K/AKT, and modified Q cycle signaling pathways. Meanwhile, the MCU, NF-κB, and JAK/STAT signaling pathways were downregulated. The PERK/eIF2α/ATF4/CHOP, PERK/SREBP-1c/FAS, IRE1, PINK1-dependent mitophagy, and AMPK/mTOR signaling pathways were bidirectionally regulated. High-quality experimental studies are needed to further elucidate the underlying mechanisms of YYFZ in CVD treatment.

Newsights of endoplasmic reticulum in hypoxia

The endoplasmic reticulum (ER) is important to cells because of its essential functions, including synthesizing three major nutrients and ion transport. When cellular homeostasis is disrupted, ER quality control (ERQC) system is activated effectively to remove misfolded and unfolded proteins through ER-phagy, ER-related degradation (ERAD), and molecular chaperones. When unfolded protein response (UPR) and ER stress are activated, the cell may be suffering a huge blow, and the most probable consequence is apoptosis. The membrane contact points between the ER and sub-organelles contribute to communication between the organelles. The decrease in oxygen concentration affects the morphology and structure of the ER, thereby affecting its function and further disrupting the stable state of cells, leading to the occurrence of disease. In this study, we describe the functions of ER-, ERQC-, and ER-related membrane contact points and their changes under hypoxia, which will help us further understand ER and treat ER-related diseases.

Mechanisms involved in the regulation of mitochondrial quality control by PGAM5 in heart failure

Heart failure (HF) refers to a group of clinical syndromes in which various heart diseases lead to the inability of cardiac output to meet the metabolic needs of the body's tissues. Cardiac metabolism requires enormous amounts of energy; thus, impaired myocardial energy metabolism is considered a key factor in the occurrence and development of HF. Mitochondria serve as the primary energy source for cardiomyocytes, and their regular functionality underpins healthy cardiac function. The mitochondrial quality control system is a crucial mechanism for regulating the functionality of cardiomyocytes, and any abnormality in this system can potentially impact the morphology and structure of mitochondria, as well as the energy metabolism of cardiomyocytes. Phosphoglycerate mutase 5 (PGAM5), a multifunctional protein, plays a key role in the regulation of mitochondrial quality control through multiple pathways. Therefore, abnormal PGAM5 function is closely related to mitochondrial damage. This article reviews the mechanism of PGAM5's involvement in the regulation of the mitochondrial quality control system in the occurrence and development of HF, thereby providing a theoretical basis for future in-depth research.

Traditional Chinese medicine and mitophagy: A novel approach for cardiovascular disease management

BACKGROUND

Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality worldwide, imposing an enormous economic burden on individuals and human society. Laboratory studies have identified several drugs that target mitophagy for the prevention and treatment of CVD. Only a few of these drugs have been successful in clinical trials, and most studies have been limited to animal and cellular models. Furthermore, conventional drugs used to treat CVD, such as antiplatelet agents, statins, and diuretics, often result in adverse effects on patients' cardiovascular, metabolic, and respiratory systems. In contrast, traditional Chinese medicine (TCM) has gained significant attention for its unique theoretical basis and clinical efficacy in treating CVD.

PURPOSE

This paper systematically summarizes all the herbal compounds, extracts, and active monomers used to target mitophagy for the treatment of CVD in the last five years. It provides valuable information for researchers in the field of basic cardiovascular research, pharmacologists, and clinicians developing herbal medicines with fewer side effects, as well as a useful reference for future mitophagy research.

METHODS

The search terms "cardiovascular disease," "mitophagy," "herbal preparations," "active monomers," and "cardiac disease pathogenesis" in combination with "natural products" and "diseases" were used to search for studies published in the past five years until January 2024.

RESULTS

Studies have shown that mitophagy plays a significant role in the progression and development of CVD, such as atherosclerosis (AS), heart failure (HF), myocardial infarction (MI), myocardial ischemia/reperfusion injury (MI/RI), cardiac hypertrophy, cardiomyopathy, and arrhythmia. Herbal compound preparations, crude extracts, and active monomers have shown potential as effective treatments for these conditions. These substances protect cardiomyocytes by inducing mitophagy, scavenging damaged mitochondria, and maintaining mitochondrial homeostasis. They display notable efficacy in combating CVD.

CONCLUSION

TCM (including herbal compound preparations, extracts, and active monomers) can treat CVD through various pharmacological mechanisms and signaling pathways by inducing mitophagy. They represent a hotspot for future cardiovascular basic research and a promising candidate for the development of future cardiovascular drugs with fewer side effects and better therapeutic efficacy.

BMAL1 alleviates myocardial damage in sepsis by activating SIRT1 signaling and promoting mitochondrial autophagy

BACKGROUND

Brain and muscle arnt-like protein-1 (BMAL1) deficiency is associated with myocardial dysfunction and suppressed sirtuin 1 (SIRT1). However, whether BMAL1 promotes mitophagy via SIRT1 to alleviate myocardial injury in sepsis remains unknown.

METHODS

An in vitro myocardial injury model was established using lipopolysaccharide (LPS)-treated H9C2 cells. Knockdown or overexpression of genes was performed using plasmid transfection. Gene and protein expression was assessed by qRT-PCR and Western blot, respectively. Cell proliferation was evaluated using cell counting kit-8, and cellular apoptosis and reactive oxygen species (ROS) levels were analyzed using flow cytometry. An in vivo myocardial injury model of sepsis was established by cecal ligation and puncture in rats. Myocardial function was characterized by analyzing the damage-associated proteins, inflammatory factors, ejection fraction, and fraction shortening.

RESULTS

sgBMAL1 significantly decreased BMAL1 levels and remarkably increased the sensitivity of H9C2 cells to LPS stimulation, consequently enhancing LPS-induced apoptosis, inflammation, and ROS levels. These effects were further attenuated by BMAL1 overexpression. BMAL1 knockdown inhibited the expression of SIRT1 and mitophagy-associated proteins. SIRT1 overexpression reversed the enhancement of shBMAL1 on cell proliferation and inflammation. In the rat model of sepsis, BMAL1 overexpression decreased the myocardial injury-associated proteins to recover the myocardial function and suppressed inflammatory activities by promoting mitophagy via SIRT1.

CONCLUSION

BMAL1 enhances mitophagy dependent on SIRT1, thereby alleviating myocardial injury in sepsis.

Mitochondrial quality control in human health and disease

Mitochondria, the most crucial energy-generating organelles in eukaryotic cells, play a pivotal role in regulating energy metabolism. However, their significance extends beyond this, as they are also indispensable in vital life processes such as cell proliferation, differentiation, immune responses, and redox balance. In response to various physiological signals or external stimuli, a sophisticated mitochondrial quality control (MQC) mechanism has evolved, encompassing key processes like mitochondrial biogenesis, mitochondrial dynamics, and mitophagy, which have garnered increasing attention from researchers to unveil their specific molecular mechanisms. In this review, we present a comprehensive summary of the primary mechanisms and functions of key regulators involved in major components of MQC. Furthermore, the critical physiological functions regulated by MQC and its diverse roles in the progression of various systemic diseases have been described in detail. We also discuss agonists or antagonists targeting MQC, aiming to explore potential therapeutic and research prospects by enhancing MQC to stabilize mitochondrial function.

Quercetin inhibits necroptosis in cardiomyocytes after ischemia-reperfusion via DNA-PKcs-SIRT5-orchestrated mitochondrial quality control

We investigated the mechanism by which quercetin preserves mitochondrial quality control (MQC) in cardiomyocytes subjected to ischemia-reperfusion stress. An enzyme-linked immunosorbent assay was employed in the in vivo experiments to assess myocardial injury markers, measure the transcript levels of SIRT5/DNAPK-cs/MLKL during various time intervals of ischemia-reperfusion, and observe structural changes in cardiomyocytes using transmission electron microscopy. In in vitro investigations, adenovirus transfection was employed to establish a gene-modified model of DNA-PKcs, and primary cardiomyocytes were obtained from a mouse model with modified SIRT5 gene. Reverse transcription polymerase chain reaction, laser confocal microscopy, immunofluorescence localization, JC-1 fluorescence assay, Seahorse energy analysis, and various other assays were applied to corroborate the regulatory influence of quercetin on the MQC network in cardiomyocytes after ischemia-reperfusion. In vitro experiments demonstrated that ischemia-reperfusion injury caused changes in the structure of the myocardium. It was seen that quercetin had a beneficial effect on the myocardial tissue, providing protection. As the ischemia-reperfusion process continued, the levels of DNA-PKcs/SIRT5/MLKL transcripts were also found to change. In vitro investigations revealed that quercetin mitigated cardiomyocyte injury caused by mitochondrial oxidative stress through DNA-PKcs, and regulated mitophagy and mitochondrial kinetics to sustain optimal mitochondrial energy metabolism levels. Quercetin, through SIRT5 desuccinylation, modulated the stability of DNA-PKcs, and together they regulated the "mitophagy-unfolded protein response." This preserved the integrity of mitochondrial membrane and genome, mitochondrial dynamics, and mitochondrial energy metabolism. Quercetin may operate synergistically to oversee the regulation of mitophagy and the unfolded protein response through DNA-PKcs-SIRT5 interaction.

Mechanism of Astragalus membranaceus (Huangqi, HQ) for treatment of heart failure based on network pharmacology and molecular docking

Heart failure is a leading cause of death in the elderly. Traditional Chinese medicine, a verified alternative therapeutic regimen, has been used to treat heart failure, which is less expensive and has fewer adverse effects. In this study, a total of 15 active ingredients of Astragalus membranaceus (Huangqi, HQ) were obtained; among them, Isorhamnetin, Quercetin, Calycosin, Formononetin, and Kaempferol were found to be linked to heart failure. Ang II significantly enlarged the cell size of cardiomyocytes, which could be partially reduced by Quercetin, Isorhamnetin, Calycosin, Kaempferol, or Formononetin. Ang II significantly up-regulated ANP, BNP, β-MHC, and CTGF expressions, whereas Quercetin, Isorhamnetin, Calycosin, Kaempferol or Formononetin treatment partially downregulated ANP, BNP, β-MHC and CTGF expressions. Five active ingredients of HQ attenuated inflammation in Ang II-induced cardiomyocytes by inhibiting the levels of TNF-α, IL-1β, IL-18 and IL-6. Molecular docking shows Isorhamnetin, Quercetin, Calycosin, Formononetin and Kaempferol can bind with its target protein ESR1 in a good bond by intermolecular force. Quercetin, Calycosin, Kaempferol or Formononetin treatment promoted the expression levels of ESR1 and phosphorylated ESR1 in Ang II-stimulated cardiomyocytes; however, Isorhamnetin treatment had no effect on ESR1 and phosphorylated ESR1 expression levels. In conclusion, our results comprehensively illustrated the bioactives, potential targets, and molecular mechanism of HQ against heart failure. Isorhamnetin, Quercetin, Calycosin, Formononetin and Kaempferol might be the primary active ingredients of HQ, dominating its cardioprotective effects against heart failure through regulating ESR1 expression, which provided a basis for the clinical application of HQ to regulate cardiac hypertrophy and heart failure.

Exploring the therapeutic potential of quercetin: A focus on its sirtuin-mediated benefits

As the global population ages, preventing lifestyle- and aging-related diseases is increasing, necessitating the search for safe and affordable therapeutic interventions. Among nutraceuticals, quercetin, a flavonoid ubiquitously present in various plants, has garnered considerable interest. This review aimed to collate and analyze existing literature on the therapeutic potentials of quercetin, especially its interactions with SIRTs and its clinical applicability based on its bioavailability and safety. This narrative review was based on a literature survey spanning from 2015 to 2023 using PUBMED. The keywords and MeSH terms used were: "quercetin" AND "bioavailability" OR "metabolism" OR "metabolites" as well as "quercetin" AND "SIRTuin" OR "SIRT*" AND "cellular effects" OR "pathway" OR "signaling" OR "neuroprotective" OR "cardioprotective" OR "nephroprotective" OR "antiatherosclerosis" OR "diabetes" OR "antidiabetic" OR "dyslipidemia" AND "mice" OR "rats". Quercetin demonstrates multiple therapeutic activities, including neuroprotective, cardioprotective, and anti-atherosclerotic effects. Its antioxidant, anti-inflammatory, antiviral, and immunomodulatory properties are well-established. At a molecular level, it majorly interacts with SIRTs, particularly SIRT1 and SIRT6, and modulates numerous signaling pathways, contributing to its therapeutic effects. These pathways play roles in reducing oxidative stress, inflammation, autophagy regulation, mitochondrial biogenesis, glucose utilization, fatty acid oxidation, and genome stability. However, clinical trials on quercetin's effectiveness in humans are scarce. Quercetin exhibits a wide range of SIRT-mediated therapeutic effects. Despite the compelling preclinical data, more standardized clinical trials are needed to fully understand its therapeutic potential. Future research should focus on addressing its bioavailability and safety concerns.

The Antioxidant Action of Astragali radix: Its Active Components and Molecular Basis

Astragali radix is a traditional medicinal herb with a long history and wide application. It is frequently used in prescriptions with other medicinal materials to replenish Qi. According to the classics of traditional Chinese medicine, Astragali radix is attributed with properties such as Qi replenishing and surface solidifying, sore healing and muscle generating, and inducing diuresis to reduce edema. Modern pharmacological studies have demonstrated that some extracts and active ingredients in Astragali radix function as antioxidants. The polysaccharides, saponins, and flavonoids in Astragali radix offer beneficial effects in preventing and controlling diseases caused by oxidative stress. However, there is still a lack of comprehensive research on the effective components and molecular mechanisms through which Astragali radix exerts antioxidant activity. In this paper, we review the active components with antioxidant effects in Astragali radix; summarize the content, bioavailability, and antioxidant mechanisms; and offer a reference for the clinical application of Astragalus and the future development of novel antioxidants.

Phenylbutyric acid inhibits hypoxia-induced trophoblast apoptosis and autophagy in preeclampsia via the PERK/ATF-4/CHOP pathway

Preeclampsia (PE) is a common pregnancy complication with a high mortality rate. Abnormally activated endoplasmic reticulum stress (ERS) is believed to be responsible for the destruction of key placental cells-trophoblasts. Phenylbutyric acid (4-PBA), an ERS inhibitor, is involved in regulating the development of ERS-related diseases. At present, how 4-PBA affects trophoblasts and its mechanisms is still unclear. In this study, PE cell models were established by stimulating HTR-8/SVneo cells with hypoxia. To verify the underlying mechanisms of 4-PBA on PE, CCT020312, an activator of PERK, was also used. The results showed that 4-PBA restored hypoxia-induced trophoblast viability, inhibited HIF-1α protein expression, inflammation, and PERK/ATF-4/CHOP pathway. Hoechst 33342 staining and flow cytometry results confirmed that 4-PBA decreased hypoxia-induced apoptosis in trophoblasts. The results of the JC-1 analysis and apoptosis initiation enzyme activity assay also demonstrated that 4-PBA inhibited apoptosis related to the mitochondrial pathway. Furthermore, by detecting autophagy in trophoblasts, an increased number of autophagic vesicles, damaged mitochondria, enhanced dansylcadaverine fluorescence, enhanced levels of autophagy proteins Beclin-1, LC3II, and decreased p62 were seen in hypoxia-stimulated cells. These changes were reversed by 4-PBA. Furthermore, it was observed that CCT020312 reversed the effects of 4-PBA on the viability, apoptosis, and autophagosome number of hypoxia-induced trophoblasts. In summary, 4-PBA reduces autophagy and apoptosis via the PERK/ATF-4/CHOP pathway and mitochondrial pathway, thereby restoring the viability of hypoxic trophoblasts. These findings provide a solid evidence base for the use of 4-PBA in PE treatment and guide a new direction for improving the outcomes of patients with PE.

Regulatory mechanism of perinatal nonylphenol exposure on cardiac mitochondrial autophagy and the PINK1/Parkin signaling pathway in male offspring rats

OBJECTIVE

This study investigated whether perinatal exposure to nonylphenol (NP) induces mitochondrial autophagy (i.e., mitophagy) damage in neonatal rat cardiomyocytes (NRCMs) and whether the PINK1/Parkin signaling pathway is involved in NP-induced primary cardiomyocyte injury.

METHODS AND RESULTS

In vivo: Perinatal NP exposure increased apoptosis and mitochondrial damage in NRCMs. Mitochondrial swelling and autophagosome-like structures with multiple concentric membranes were observed in the 100 mg/kg NP group, with an increase in the number of autophagosomes. Disorganized fiber arrangement and elevated serum myocardial enzyme levels were observed with increasing NP dosage. Additionally, NP exposure led to increased MDA levels and decreased SOD activity and ATP levels in myocardial tissue. The mRNA expression levels of autophagy-related genes, including Beclin-1, p62, and LC3B, as well as the expression of mitochondrial autophagy-related proteins (PINK1, p-Parkin, Parkin, Beclin-1, p62, LC3-I, LC3-II, and LC3-II/I) and apoptosis-related proteins (Bax and caspase-3), increased, whereas the expression levels of the mitochondrial membrane protein TOMM20 and the anti-apoptotic protein Bcl-2 decreased. In vitro: NP increased ROS levels, LDH release, and decreased ATP levels in NRCMs. CsA treatment significantly inhibited the expression of autophagy-related proteins (Beclin-1, LC3-II/I, and p62) and apoptosis-related proteins (caspase-3 and Bax), increased the expression levels of TOMM20 and Bcl-2 proteins, increased cellular ATP levels, and inhibited LDH release. The inhibition of the PINK1/Parkin signaling pathway suppressed the expression of mitochondrial autophagy-related proteins (PINK1, p-Parkin, Parkin, Beclin-1, LC3-II/I, and p62) and apoptosis-related proteins (caspase-3 and Bax), increased TOMM20 and Bcl-2 protein expression, increased ATP levels, and decreased LDH levels in NRCMs.

CONCLUSIONS

This study is novel in reporting that perinatal NP exposure induced myocardial injury in male neonatal rats, thereby inducing mitophagy. The PINK1/Parkin signaling pathway was involved in this injury by regulating mitophagy.

Zishen Tongyang Huoxue decoction (TYHX) alleviates sinoatrial node cell ischemia/reperfusion injury by directing mitochondrial quality control via the VDAC1-β-tubulin signaling axis

ETHNOPHARMACOLOGICAL RELEVANCE

Zishen Tongyang Huoxue decoction (TYHX) has been used clinically for nearly 40 years to treat sick sinus syndrome. Previous reports showed that TYHX can inhibit calcium flux by regulating mitochondrial homeostasis via β-tubulin and increase sinoatrial node cell (SNC) activity. However, the underlying mechanisms remain unclear.

AIM OF THE STUDY

We aimed to verify the protective effect of TYHX against SNC ischemia by regulating mitochondrial quality control (MQC) through β-tubulin and voltage-dependent anion-selective channel 1 (VDAC1) silencing.

MATERIALS AND METHODS

We established an in vitro model of SNC ischemia/reperfusion (I/R) injury and performed rescue experiments by silencing β-tubulin and VDAC1 expression. Cell-Counting Kit 8 assays were performed to detect cell viabilities, and terminal deoxynucleotidyl transferase dUTP nick-end labeling assays (paired with confocal microscopy) were performed to detect fragmentation. Mitochondrial-energy metabolism was detected using the Seahorse assay system. Reverse transcription-quantitative polymerase chain reaction analysis was performed to detect the mRNA-expression levels of MQC-related genes.

RESULTS

TYHX inhibited SNC mitochondrial injury. During I/R simulation, TYHX maintained β-tubulin stability, regulated synergy between mitophagy and the mitochondrial unfolded-protein response (UPRmt), and inhibited mitochondrial oxidative stress and overactive SNC fission. Next-generation sequencing suggested that mitochondrial-membrane injury caused SNC apoptosis. We also found that TYHX regulated β-tubulin expression through VDAC1 and inhibited dynamin-related protein 1 migration to mitochondria from the nucleus. After preventing excessive mitochondrial fission, the mitophagy-UPRmt pathway, mitochondrial-membrane potential, and mitochondrial energy were restored. VDAC1 silencing affected the regulatory mechanism of MQC in a β-tubulin-dependent manner via TYHX.

CONCLUSION

TYHX regulated mitochondrial membrane-permeability through VDAC1, which affected MQC through β-tubulin and inhibited mitochondrial apoptosis. Our findings may help in developing drugs to protect the sinoatrial node.

The potential of herbal drugs to treat heart failure: The roles of Sirt1/AMPK

Heart failure (HF) is a highly morbid syndrome that seriously affects the physical and mental health of patients and generates an enormous socio-economic burden. In addition to cardiac myocyte oxidative stress and apoptosis, which are considered mechanisms for the development of HF, alterations in cardiac energy metabolism and pathological autophagy also contribute to cardiac abnormalities and ultimately HF. Silent information regulator 1 (Sirt1) and adenosine monophosphate-activated protein kinase (AMPK) are nicotinamide adenine dinucleotide (NAD+)-dependent deacetylases and phosphorylated kinases, respectively. They play similar roles in regulating some pathological processes of the heart through regulating targets such as peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), protein 38 mitogen-activated protein kinase (p38 MAPK), peroxisome proliferator-activated receptors (PPARs), and mammalian target of rapamycin (mTOR). We summarized the synergistic effects of Sirt1 and AMPK in the heart, and listed the traditional Chinese medicine (TCM) that exhibit cardioprotective properties by modulating the Sirt1/AMPK pathway, to provide a basis for the development of Sirt1/AMPK activators or inhibitors for the treatment of HF and other cardiovascular diseases (CVDs).

Quercetin and dasatinib, two powerful senolytics in age-related cardiovascular disease

Cellular senescence is characteristic of the development and progression of multiple age-associated diseases. Accumulation of senescent cells in the heart contributes to various age-related pathologies. Several compounds called senolytics have been designed to eliminate these cells within the tissues. In recent years, the use and study of senolytics increased, representing a promising field for finding accessible and safe therapies for cardiovascular disease (CVD) treatment. This mini-review discusses the changes in the aging heart and the participation of senescent cells in CVD, as well as the use of senolytics to prevent the progression of myocardial damage, mainly the effect of dasatinib and quercetin. In particular, the mechanisms and physiological effects of senolytics therapies in the aged heart are discussed.

Lipotoxicity, ER Stress, and Cardiovascular Disease: Current Understanding and Future Directions

The endoplasmic reticulum (ER) is a sub-cellular organelle that is responsible for the correct folding of proteins, lipid biosynthesis, calcium storage, and various post-translational modifications. In the disturbance of ER functioning, unfolded or misfolded proteins accumulate inside the ER lumen and initiate downstream signaling called unfolded protein response (UPR). The UPR signaling pathway is involved in lipolysis, triacylglycerol synthesis, lipogenesis, the mevalonate pathway, and low-density lipoprotein receptor recycling. ER stress also affects lipid metabolism by changing the levels of enzymes that are involved in the synthesis or modifications of lipids and causing lipotoxicity. Lipid metabolism and cardiac diseases are in close association as the deregulation of lipid metabolism leads to the development of various cardiovascular diseases (CVDs). Several studies have suggested that lipotoxicity is one of the important factors for cardiovascular disorders. In this review, we will discuss how ER stress affects lipid metabolism and their interplay in the development of cardiovascular disorders. Further, the current therapeutics available to target ER stress and lipid metabolism in various CVDs will be summarized.

SIRT1 is a regulator of autophagy: Implications for the progression and treatment of myocardial ischemia-reperfusion

SIRT1 is a highly conserved nicotinamide adenine dinucleotide (NAD+)-dependent histone deacetylase. It is involved in the regulation of various pathophysiological processes, including cell proliferation, survival, differentiation, autophagy, and oxidative stress. Therapeutic activation of SIRT1 protects the heart and cardiomyocytes from pathology-related stress, particularly myocardial ischemia/reperfusion (I/R). Autophagy is an important metabolic pathway for cell survival during energy or nutrient deficiency, hypoxia, or oxidative stress. Autophagy is a double-edged sword in myocardial I/R injury. The activation of autophagy during the ischemic phase removes excess metabolic waste and helps ensure cardiomyocyte survival, whereas excessive autophagy during reperfusion depletes the cellular components and leads to autophagic cell death. Increasing research on I/R injury has indicated that SIRT1 is involved in the process of autophagy and regulates myocardial I/R. SIRT1 regulates autophagy through various pathways, such as the deacetylation of FOXOs, ATGs, and LC3. Recent studies have confirmed that SIRT1-mediated autophagy plays different roles at different stages of myocardial I/R injury. By targeting the mechanism of SIRT1-mediated autophagy at different stages of I/R injury, new small-molecule drugs, miRNA activators, or blockers can be developed. For example, resveratrol, sevoflurane, quercetin, and melatonin in the ischemic stage, coptisine, curcumin, berberine, and some miRNAs during reperfusion, were involved in regulating the SIRT1-autophagy axis, exerting a cardioprotective effect. Here, we summarize the possible mechanisms of autophagy regulation by SIRT1 in myocardial I/R injury and the related molecular drug applications to identify strategies for treating myocardial I/R injury.

Ginsenoside Rd attenuates myocardial ischemia injury through improving mitochondrial biogenesis via WNT5A/Ca2+ pathways

Ginsenoside Rd, one of the main active components in ginseng, exerts various biological activities. However, its effectiveness on myocardial ischemia injury and its potential mechanism need further clarification. The model of isoproterenol (ISO)-induced myocardial ischemia injury (MI) mice and cobalt chloride (CoCl2)-induced cardiomyocytes injury were performed. Ginsenoside Rd significantly alleviated MI injury, as evidenced by ameliorated cardiac pathological features and improved cardiac function. Simultaneously, ginsenoside Rd notably mitigated CoCl2-induced cell injury, decreased the lactate dehydrogenase (LDH) release and reactive oxygen species (ROS) generation in vitro. Additionally, ginsenoside Rd increased nicotinamide adenine dinucleotide (NADH) and mitochondrial membrane potential (MMP). Moreover, we found that ginsenoside Rd could increase the mitochondrial DNA (mtDNA) and promote the expression of Peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC1α), nuclear factor erythroid 2 related factor-1 (NRF1), nuclear factor erythroid 2 related factor-2 (NRF2) and activating mitochondrial transcription factor A (TFAM), which suggested that ginsenoside Rd might accelerate mitochondrial biogenesis function to ameliorate MI injury. Importantly, ginsenoside Rd treatment significantly inhibited the WNT5A/calcium (Ca2+) signaling pathway, decreased the expression of WNT5A, Frizzled2, phosphorylated calmodulin kinase II/calmodulin kinase II (p-CaMKII/CaMKII) and the calcium overload. Meanwhile, WNT5A siRNA was further conducted to elucidate the effect of ginsenoside Rd on CoCl2-induced cardiomyocyte injury. And we found that WNT5A siRNA partially weakened the protective effects of ginsenoside Rd on mitochondrial function and mitochondrial biogenesis, suggesting that ginsenoside Rd might suppress myocardial ischemia injury through WNT5A. Overall, this study demonstrated that ginsenoside Rd could alleviate myocardial ischemia injury through improving mitochondrial biogenesis via WNT5A/Ca2+ pathways, which provided a rationale for future clinical applications and potential drugs for the treatment of cardiovascular diseases.

The Current State of Research on Sirtuin-Mediated Autophagy in Cardiovascular Diseases

Sirtuins belong to the class III histone deacetylases and possess nicotinamide adenine dinucleotide-dependent deacetylase activity. They are involved in the regulation of multiple signaling pathways implicated in cardiovascular diseases. Autophagy is a crucial adaptive cellular response to stress stimuli. Mounting evidence suggests a strong correlation between Sirtuins and autophagy, potentially involving cross-regulation and crosstalk. Sirtuin-mediated autophagy plays a crucial regulatory role in some cardiovascular diseases, including atherosclerosis, ischemia/reperfusion injury, hypertension, heart failure, diabetic cardiomyopathy, and drug-induced myocardial damage. In this context, we summarize the research advancements pertaining to various Sirtuins involved in autophagy and the molecular mechanisms regulating autophagy. We also elucidate the biological function of Sirtuins across diverse cardiovascular diseases and further discuss the development of novel drugs that regulate Sirtuin-mediated autophagy.

Exploring the effects and mechanisms of Guizhigancao Decoction on heart failure using an integrated approach based on experimental support and network pharmacology strategy

Background and aim

HF (Heart Failure) is the leading cause of mortality and is a significant clinical problem affecting millions of patients worldwide. To date, the mechanisms of HF remain largely elusive. The effective treatments contributing to HF remain incompletely understood. Therefore, the development of an effective strategy for HF is urgently needed.

Experimental procedure

In the present study, we devoted to investigating the effective treatments and sought to systematically decipher the related molecular mechanisms of Guizhigancao Decoction (GZGCD, Cinnamomum cassia Presl and Glycyrrhizae Radix Et Rhizoma Praeparata Cum Melle) for treating HF. We examined the therapeutic effect of GZGCD on HF in vivo. An integrative approach combining biomarker examination, echocardiography, myocardial fibrosis and cardiac apoptosis condition using Masson and TUNEL staining was performed to assess the efficacy of GZGCD against HF. Subsequently, comprehensive network pharmacology analyses were performed to explore the mechanisms involved in GZGCD therapeutic effects on HF.

Results and conclusions

The results showed that GZGCD could reverse cardiac function in rats with HF by reducing NT-proBNP, increasing EF, decreasing LVESV, LVEDV, LVIDs, LVIDd, increasing running time, and ameliorate myocardial collagen fiber hyperplasia and cardiomyocyte apoptosis. We showed that GZGCD might contribute to HF treatment via oxidative related pathways through bioinformatics. Eventually, promising compound quercetin in GZGCD for HF therapeutics was proposed in database-based analysis. Collectively, our findings indicate that GZGCD has a treatment effect on HF. We proposed that GZGCD might contribute HF treatment via oxidative response-related pathways.

Targeting oxidative stress as a preventive and therapeutic approach for cardiovascular disease

Cardiovascular diseases (CVDs) continue to exert a significant impact on global mortality rates, encompassing conditions like pulmonary arterial hypertension (PAH), atherosclerosis (AS), and myocardial infarction (MI). Oxidative stress (OS) plays a crucial role in the pathogenesis and advancement of CVDs, highlighting its significance as a contributing factor. Maintaining an equilibrium between reactive oxygen species (ROS) and antioxidant systems not only aids in mitigating oxidative stress but also confers protective benefits on cardiac health. Herbal monomers can inhibit OS in CVDs by activating multiple signaling pathways, such as increasing the activity of endogenous antioxidant systems and decreasing the level of ROS expression. Given the actions of herbal monomers to significantly protect the normal function of the heart and reduce the damage caused by OS to the organism. Hence, it is imperative to recognize the significance of herbal monomers as prospective therapeutic interventions for mitigating oxidative damage in CVDs. This paper aims to comprehensively review the origins and mechanisms underlying OS, elucidate the intricate association between CVDs and OS, and explore the therapeutic potential of antioxidant treatment utilizing herbal monomers. Furthermore, particular emphasis will be placed on examining the cardioprotective effects of herbal monomers by evaluating their impact on cardiac signaling pathways subsequent to treatment.

Chemical mitophagy modulators: Drug development strategies and novel regulatory mechanisms

Maintaining mitochondrial homeostasis is a potential therapeutic strategy for various diseases, including neurodegenerative diseases, cardiovascular diseases, metabolic disorders, and cancer. Selective degradation of mitochondria by autophagy (mitophagy) is a fundamental mitochondrial quality control mechanism conserved from yeast to humans. Indeed, small-molecule modulators of mitophagy are valuable pharmaceutical tools that can be used to dissect complex biological processes and turn them into potential drugs. In the past few years, pharmacological regulation of mitophagy has shown promising therapeutic efficacy in various disease models. However, with the increasing number of chemical mitophagy modulator studies, frequent methodological flaws can be observed, leading some studies to draw unreliable or misleading conclusions. This review attempts (a) to summarize the molecular mechanisms of mitophagy; (b) to propose a Mitophagy Modulator Characterization System (MMCS); (c) to perform a comprehensive analysis of methods used to characterize mitophagy modulators, covering publications over the past 20 years; (d) to provide novel targets for pharmacological intervention of mitophagy. We believe this review will provide a panorama of current research on chemical mitophagy modulators and promote the development of safe and robust mitophagy modulators with therapeutic potential by introducing high methodological standards.

Cellular and molecular biology of sirtuins in cardiovascular disease

Sirtuins (SIRTs) are a nicotinic adenine dinucleotide (+) -dependent histone deacetylase that regulates critical signaling pathways in prokaryotes and eukaryotes. Studies have identified seven mammalian homologs of the yeast SIRT silencing message regulator 2, namely, SIRT1-SIRT7. Recent in vivo and in vitro studies have successfully demonstrated the involvement of SIRTs in key pathways for cell biological function in physiological and pathological processes of the cardiovascular system, including processes including cellular senescence, oxidative stress, apoptosis, DNA damage, and cellular metabolism. Emerging evidence has stimulated a significant evolution in preventing and treating cardiovascular disease (CVD). Here, we review the important roles of SIRTs for the regulatory pathways involved in the pathogenesis of cardiovascular diseases and their molecular targets, including novel protein post-translational modifications of succinylation. In addition, we summarize the agonists and inhibitors currently identified to target novel specific small molecules of SIRTs. A better understanding of the role of SIRTs in the biology of CVD opens new avenues for therapeutic intervention with great potential for preventing and treating CVD.

Impact of polyphenols on heart failure and cardiac hypertrophy: clinical effects and molecular mechanisms

Polyphenols are abundant in regular diets and possess antioxidant, anti-inflammatory, anti-cancer, neuroprotective, and cardioprotective effects. Regarding the inadequacy of the current treatments in preventing cardiac remodeling following cardiovascular diseases, attention has been focused on improving cardiac function with potential alternatives such as polyphenols. The following online databases were searched for relevant orginial published from 2000 to 2023: EMBASE, MEDLINE, and Web of Science databases. The search strategy aimed to assess the effects of polyphenols on heart failure and keywords were "heart failure" and "polyphenols" and "cardiac hypertrophy" and "molecular mechanisms". Our results indicated polyphenols are repeatedly indicated to regulate various heart failure-related vital molecules and signaling pathways, such as inactivating fibrotic and hypertrophic factors, preventing mitochondrial dysfunction and free radical production, the underlying causes of apoptosis, and also improving lipid profile and cellular metabolism. In the current study, we aimed to review the most recent literature and investigations on the underlying mechanism of actions of different polyphenols subclasses in cardiac hypertrophy and heart failure to provide deep insight into novel mechanistic treatments and direct future studies in this context. Moreover, due to polyphenols' low bioavailability from conventional oral and intravenous administration routes, in this study, we have also investigated the currently accessible nano-drug delivery methods to optimize the treatment outcomes by providing sufficient drug delivery, targeted therapy, and less off-target effects, as desired by precision medicine standards.

Pharmacological mechanism of natural drugs and their active ingredients in the treatment of arrhythmia via calcium channel regulation

Arrhythmia is characterized by abnormal heartbeat rhythms and frequencies caused by heart pacing and conduction dysfunction. Arrhythmia is the leading cause of death in patients with cardiovascular disease, with high morbidity and mortality rates, posing a serious risk to human health. Natural drugs and their active ingredients, such as matrine(MAT), tetrandrine(TET), dehydroevodiamine, tanshinone IIA, and ginsenosides, have been widely used for the treatment of atrial fibrillation, ventricular ectopic beats, sick sinus syndrome, and other arrhythmia-like diseases owing to their unique advantages. This review summarizes the mechanism of action of natural drugs and their active ingredients in the treatment of arrhythmia via the regulation of Ca²⁺, such as alkaloids, quinones, saponins, terpenoids, flavonoids, polyphenols, and lignan compounds, to provide ideas for the innovative development of natural drugs with potential antiarrhythmic efficacy.

Mitochondrial disorder and treatment of ischemic cardiomyopathy: Potential and advantages of Chinese herbal medicine

Mitochondrial dysfunction is the main cause of damage to the pathological mechanism of ischemic cardiomyopathy. In addition, mitochondrial dysfunction can also affect the homeostasis of cardiomyocytes or endothelial cell dysfunction, leading to a vicious cycle of mitochondrial oxidative stress. And mitochondrial dysfunction is also an important pathological basis for ischemic cardiomyopathy and reperfusion injury after myocardial infarction or end-stage coronary heart disease. Therefore, mitochondria can be used as therapeutic targets against myocardial ischemia injury, and the regulation of mitochondrial morphology, function and structure is a key and important way of targeting mitochondrial quality control therapeutic mechanisms. Mitochondrial quality control includes mechanisms such as mitophagy, mitochondrial dynamics (mitochondrial fusion/fission), mitochondrial biosynthesis, and mitochondrial unfolded protein responses. Among them, the increase of mitochondrial fragmentation caused by mitochondrial pathological fission is the initial factor. The protective mitochondrial fusion can strengthen the interaction and synthesis of paired mitochondria and promote mitochondrial biosynthesis. In ischemia or hypoxia, pathological mitochondrial fission can promote the formation of mitochondrial fragments, fragmented mitochondria can lead to damaged mitochondrial DNA production, which can lead to mitochondrial biosynthesis dysfunction, insufficient mitochondrial ATP production, and mitochondrial ROS. Burst growth or loss of mitochondrial membrane potential. This eventually leads to the accumulation of damaged mitochondria. Then, under the leadership of mitophagy, damaged mitochondria can complete the mitochondrial degradation process through mitophagy, and transport the morphologically and structurally damaged mitochondria to lysosomes for degradation. But once the pathological mitochondrial fission increases, the damaged mitochondria increases, which may activate the pathway of cardiomyocyte death. Although laboratory studies have found that a variety of mitochondrial-targeted drugs can reduce myocardial ischemia and protect cardiomyocytes, there are still few drugs that have successfully passed clinical trials. In this review, we describe the role of MQS in ischemia/hypoxia-induced cardiomyocyte physiopathology and elucidate the relevant mechanisms of mitochondrial dysfunction in ischemic cardiomyopathy. In addition, we also further explained the advantages of natural products in improving mitochondrial dysfunction and protecting myocardial cells from the perspective of pharmacological mechanism, and explained its related mechanisms. Potential targeted therapies that can be used to improve MQS under ischemia/hypoxia are discussed, aiming to accelerate the development of cardioprotective drugs targeting mitochondrial dysfunction.

Quercetin and Its Derivative Counteract Palmitate-Dependent Lipotoxicity by Inhibiting Oxidative Stress and Inflammation in Cardiomyocytes

Cardiac lipotoxicity plays an important role in the pathogenesis of obesity-related cardiovascular disease. The flavonoid quercetin (QUE), a nutraceutical compound that is abundant in the "Mediterranean diet", has been shown to be a potential therapeutic agent in cardiac and metabolic diseases. Here, we investigated the beneficial role of QUE and its derivative Q2, which demonstrates improved bioavailability and chemical stability, in cardiac lipotoxicity. To this end, H9c2 cardiomyocytes were pre-treated with QUE or Q2 and then exposed to palmitate (PA) to recapitulate the cardiac lipotoxicity occurring in obesity. Our results showed that both QUE and Q2 significantly attenuated PA-dependent cell death, although QUE was effective at a lower concentration (50 nM) when compared with Q2 (250 nM). QUE decreased the release of lactate dehydrogenase (LDH), an important indicator of cytotoxicity, and the accumulation of intracellular lipid droplets triggered by PA. On the other hand, QUE protected cardiomyocytes from PA-induced oxidative stress by counteracting the formation of malondialdehyde (MDA) and protein carbonyl groups (which are indicators of lipid peroxidation and protein oxidation, respectively) and intracellular ROS generation, and by improving the enzymatic activities of catalase and superoxide dismutase (SOD). Pre-treatment with QUE also significantly attenuated the inflammatory response induced by PA by reducing the release of key proinflammatory cytokines (IL-1β and TNF-α). Similar to QUE, Q2 (250 nM) also significantly counteracted the PA-provoked increase in intracellular lipid droplets, LDH, and MDA, improving SOD activity and decreasing the release of IL-1β and TNF-α. These results suggest that QUE and Q2 could be considered potential therapeutics for the treatment of the cardiac lipotoxicity that occurs in obesity and metabolic diseases.

Pomegranate Peel in the Amelioration of High-Altitude Disease: A Network Pharmacology and Molecular Docking Study of Underlying Mechanisms

High-altitude disease (HAD) describes the failure to adapt to the lack of oxygen found at high altitudes and therapeutic antioxidant effects have been attributed to pomegranate peel (PP) extract. Network pharmacology, molecular docking, and experimental validation were used to study mechanisms responsible for the alleviation of HAD by PP. The aim was to establish a reference for future research and aid technological development, particularly in clinical settings. Network pharmacology analysis showed that PP affected many targets in HAD via the active ingredients, luteolin 7-O-glycoside, punicalagin, and ellagic acid. HNRNPA1, HSPA1B, HSPA1A, CUL4B, CLTC, PPP1CA, PARP1, RACK1, NEDD8, and MAP3K1 were all targets, responsible for effects on ribosomes, apoptosis, cell cycle, mRNA surveillance pathway, and the MAPK signaling pathway. PP had an antiapoptosis effect on H9c2 cells damaged by hypoxia, as shown by annexinV-FITC/PI double staining. Practical Applications. HAD comprises a group of diseases caused by failure to adapt to a low-oxygen environment. PP extract has previously been shown to have antioxidant effects. PP attenuated damage to H9c2 cells and reduced the apoptosis rate. The current results lay the foundation for further experimental investigations.

Effect of Xuefu Zhuyu Capsule on Myocardial Infarction: Network Pharmacology and Experimental Verification

Background

Myocardial infarction (MI) is the most severe manifestation of cardiovascular disease. Xuefu Zhuyu Capsule (XFC), a proprietary Chinese medicine, is widely used in various cardiovascular diseases. At present, the molecular mechanism of XFC remains unclear.

Objective

To explore the mechanism of anti-MI effects of XFC by combining network pharmacology and experiments.

Methods

TCMSP, GeneCards, and DisGeNET databases were used to find the target of XFC. PPI analysis was performed by the STRING database. KEGG and GO analyses were performed by Metascape Database. Molecular docking was performed by Autodock Vina. HE staining, echocardiography, immunofluorescence, and TUNEL were performed to verify the prediction results.

Results

Network pharmacology showed that quercetin, kaempferol, β-sitosterol, luteolin, and baicalein were the main active ingredients of XFC. TNF, IL6, TP53, VEGFA, JUN, CASP3, and SIRT1 were the main targets of XFC. KEGG results showed that key genes were mainly enriched in lipid and atherosclerosis, PI3K-Akt signaling pathway, MAPK signaling pathway, and NF-κB signaling pathway. HE staining showed that XFC could improve the morphology of myocardial tissue. Echocardiography showed that XFC could improve cardiac function. TUNEL showed that XFC could reduce cardiomyocyte apoptosis. Immunofluorescence showed that XFC could reduce the expression of α-smooth muscle actin (α-SMA) and increase the expression of CD31. In addition, we found that XFC may exert its therapeutic effects through SIRT1.

Conclusion

This study demonstrated that SIRT1 may be the target of XFC in the treatment of MI. The active ingredients of XFC and SIRT1 can be stably bound. XFC could inhibit apoptosis, promote angiogenesis, and improve myocardial fibrosis through SIRT1.

Endoplasmic reticulum as a target in cardiovascular diseases: Is there a role for flavonoids?

Flavonoids are found in natural health products and plant-based foods. The flavonoid molecules contain a 15-carbon skeleton with the particular structural construction of subclasses. The most flavonoid's critical subclasses with improved health properties are the catechins or flavonols (e.g., epigallocatechin 3-gallate from green tea), the flavones (e.g., apigenin from celery), the flavanones (e.g., naringenin from citrus), the flavanols (e.g., quercetin glycosides from berries, onion, and apples), the isoflavones (e.g., genistein from soya beans) and the anthocyanins (e.g., cyanidin-3-O-glucoside from berries). Scientific data conclusively demonstrates that frequent intake of efficient amounts of dietary flavonoids decreases chronic inflammation and the chance of oxidative stress expressing the pathogenesis of human diseases like cardiovascular diseases (CVDs). The endoplasmic reticulum (ER) is a critical organelle that plays a role in protein folding, post-transcriptional conversion, and transportation, which plays a critical part in maintaining cell homeostasis. Various stimuli can lead to the creation of unfolded or misfolded proteins in the endoplasmic reticulum and then arise in endoplasmic reticulum stress. Constant endoplasmic reticulum stress triggers unfolded protein response (UPR), which ultimately causes apoptosis. Research has shown that endoplasmic reticulum stress plays a critical part in the pathogenesis of several cardiovascular diseases, including diabetic cardiomyopathy, ischemic heart disease, heart failure, aortic aneurysm, and hypertension. Endoplasmic reticulum stress could be one of the crucial points in treating multiple cardiovascular diseases. In this review, we summarized findings on flavonoids' effects on the endoplasmic reticulum and their role in the prevention and treatment of cardiovascular diseases.

Molecular Mechanisms of Mitochondrial Quality Control in Ischemic Cardiomyopathy

Ischemic cardiomyopathy (ICM) is a special type of coronary heart disease or an advanced stage of the disease, which is related to the pathological mechanism of primary dilated cardiomyopathy. Ischemic cardiomyopathy mainly occurs in the long-term myocardial ischemia, resulting in diffuse myocardial fibrosis. This in turn affects the cardiac ejection function, resulting in a significant impact on myocardial systolic and diastolic function, resulting in a decrease in the cardiac ejection fraction. The pathogenesis of ICM is closely related to coronary heart disease. Mainly due to coronary atherosclerosis caused by coronary stenosis or vascular occlusion, causing vascular inflammatory lesions and thrombosis. As the disease progresses, it leads to long-term myocardial ischemia and eventually ICM. The pathological mechanism is mainly related to the mechanisms of inflammation, myocardial hypertrophy, fibrosis and vascular remodeling. Mitochondria are organelles with a double-membrane structure, so the composition of the mitochondrial outer compartment is basically similar to that of the cytoplasm. When ischemia-reperfusion induces a large influx of calcium into the cell, the concentration of calcium ions in the mitochondrial outer compartment also increases. The subsequent opening of the membrane permeability transition pore in the inner mitochondrial membrane and the resulting calcium overload induces the homeostasis of cardiomyocytes and activates the mitochondrial pathway of apoptosis. Mitochondrial Quality Control (MQC), as an important mechanism for regulating mitochondrial function in cardiomyocytes, affects the morphological structure/function and lifespan of mitochondria. In this review, we discuss the role of MQC (including mitophagy, mitochondrial dynamics, and mitochondrial biosynthesis) in the pathogenesis of ICM and provide important evidence for targeting MQC for ICM.

ß-tubulin contributes to Tongyang Huoxue decoction-induced protection against hypoxia/reoxygenation-induced injury of sinoatrial node cells through SIRT1-mediated regulation of mitochondrial quality surveillance

BACKGROUND

TYHX-Tongyang Huoxue decoction has been used clinically for nearly 40 years. The ingredients of TYHX are Radix Astragali (Huangqi), Red Ginseng (Hongshen), Rehmannia Glutinosa (Dihuang), Common Yam Rhizome (Shanyao) and Cassia-bark-tree Bark (Rougui). Our previous experiments confirmed that TYHX can protect sinoatrial node cells. However, its mechanism of action is not completely understood yet.

PURPOSE

The present study aimed to determine the protective effects of TYHX against Sinus node cell injury under hypoxic stress and elucidate the underlying mechanisms of protection.

METHODS

Through RNA sequencing analysis and network pharmacology analysis, we found significant differences in mitochondrial-related genes before and after hypoxia-mimicking SNC, resolved the main regulatory mechanism of TYHX. Through the intervention of TYHX on SNC, a series of detection methods such as laser confocal, fluorescence co-localization, mitochondrial membrane potential and RT-PCR. The regulatory effect of TYHX on β-tubulin in sinoatrial node cells was verified by in vitro experiments. The mechanism of action of TYHX and its active ingredient quercetin to maintain mitochondrial homeostasis and protect sinoatrial node cells through mitophagy, mitochondrial fusion/fission and mitochondrial biosynthesis was confirmed.

RESULTS

Through RNA sequencing analysis, we found that there were significant differences in mitochondrial related genes before and after SNC was modeled by hypoxia. Through pharmacological experiments, we showed that TYHX could inhibit the migration of Drp1 to mitochondria, inhibit excessive mitochondrial fission, activate mitophagy and increase the mitochondrial membrane potential. These protective effects were mainly mediated by β-tubulin. Furthermore, the active component quercetin in TYHX could inhibit excessive mitochondrial fission through SIRT1, maintain mitochondrial energy metabolism and protect SNCs. Our results showed that protection of mitochondrial function through the maintenance of β-tubulin and activation of SIRT1 is the main mechanism by which TYHX alleviates hypoxic stress injury in SNCs. The regulatory effects of TYHX and quercetin on mitochondrial quality surveillance are also necessary. Our findings provide empirical evidence supporting the use of TYHX as a targeted treatment for sick sinus syndrome.

CONCLUSION

Our data indicate that TYHX exerts protective effects against sinus node cell injury under hypoxic stress, which may be associated with the regulation of mitochondrial quality surveillance (MQS) and inhibition of mitochondrial homeostasis-mediated apoptosis.

Network pharmacology-based and experimental identification of the effects of Renshen Yangrong decoction on myocardial infarction

Objective: Myocardial infarction (MI) is one of the leading causes of death worldwide. Currently, the drugs used to treat MI have various side effects. Emerging evidence supports the protective effects of Renshen Yangrong Decoction (RSYRD) in cardiovascular diseases (CVDs) treatments, with few side effect reports. However, the role of RSYRD in MI remains unclear. In this study, network pharmacological analysis was combined with experiments in vivo and in vitro to validate the effects of RSYRD in the treatment during the early stage of MI.

Methods: Firstly, network pharmacology analysis was performed to search for the potential targets and signaling pathways of RSYRD in the early stage of MI. Then, the protein-protein interaction (PPI) network was constructed to identify the core genes of RSYRD that may play a key role in MI. At last, the treatment effectiveness of RSYRD on MI was verified via experiments in vitro and in vivo.

Results: RSYRD contained fifty-six bioactive components. Eighty-eight intersections between RSYRD and MI targets and thirteen core genes were screened. KEGG and GO functional enrichment analyses predicted that RSYRD might play a therapeutic role in MI through oxidative stress, apoptosis, and immune-inflammatory signaling pathways. In vivo and in vitro experiment results revealed that significant apoptosis occurred in myocardial tissue in the early stage of MI. Moreover, the levels of reactive oxide species (ROS), TNF-α, and IL-6 increased markedly. After RSYRD administration, they significantly decreased. At the mechanistic level, RSYRD could reduce ROS production to alleviate cell apoptosis.

Conclusion: RSYRD could reduce neonatal mouse cardiomyocytes (NMCMs) apoptosis by lowering ROS production induced by hypoxia and improve the cardiac function of mice 3 days post-MI. RSYRD could also reduce the levels of TNF-α and IL-6 in the serum of mice.

Mitophagy in cardiovascular diseases: molecular mechanisms, pathogenesis, and treatment

With the growing prevalence of cardiovascular disease (CVD), there is an urgent need to explore non-conventional therapeutic measures to alleviate the burden of CVD on global healthcare. Mitochondrial injury plays a cardinal role in the pathogenesis of CVD. Mitochondrial dynamics and mitophagy are essential machineries that govern mitochondrial health in cardiomyocytes in physiological and pathophysiological settings. However, with the onset and progression of CVD, homeostasis of mitophagy is disturbed through largely unknown pathological mechanisms, causing mitochondrial damage and ultimately cardiomyocyte death. In this review we decipher the dual regulatory role of mitophagy in CVD pathogenesis, summarize controversies in mitophagy, and highlight recently identified compounds capable of modulating mitophagy. We share our perspectives on future mitophagy research directions in the context of CVD.

Investigating the cardioprotective effects of Fuzheng Yangxin recipe based on network pharmacology and experimental evaluation

Background: Under Chinese medicine theory guidance, Fuzheng Yangxin Recipe (FZYX) is clinically effective for the treatment of heart failure (HF) caused by ischemic heart disease (IHD). This study aimed to investigate the mechanism of the myocardial protective effects of FZYX on HF.

Materials and methods: The Gene expression omnibus database was used to identify differential genes of the IHD subtype. Through network pharmacological methods, the targets of the active components of FZYX were obtained. We also constructed IHD-induced HF model rats by ligating the left anterior descending coronary artery. Echocardiography, pathological section staining, enzyme-linked immunosorbent assay, western blotting, immunohistochemistry, and quantitative real-time PCR analyses were performed to verify the protective effects of FZYX on the myocardium.

Results: We identified 53 active components and 37 potential targets of FZYX associated with the IHD subtype. Signal transducer and activator of transcription 3 (STAT3) is a key protein in the protein-protein interaction (PPI) network. A total of 146 biological processes, 10 cellular components and 40 molecular function subcategories were identified by Gene Ontology (GO) enrichment analysis, and 18 signalling pathways, including apoptosis, were identified by Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. In vivo experiments showed that FZYX significantly inhibited cardiomyocyte apoptosis, promoted the expression and phosphorylation of STAT3, and improved cardiac function.

Conclusion: FZXY improves cardiac function and protects cardiomyocytes from injury via multi-component, multi-target and multi-pathway action, especially its possible role in regulating STAT3 expression and anti-apoptotic effect.

The Role of Mitochondrial Quality Control in Anthracycline-Induced Cardiotoxicity: From Bench to Bedside

Cardiotoxicity is the major side effect of anthracyclines (doxorubicin, daunorubicin, epirubicin, and idarubicin), though being the most commonly used chemotherapy drugs and the mainstay of therapy in solid and hematological neoplasms. Advances in the field of cardio-oncology have expanded our understanding of the molecular mechanisms underlying anthracycline-induced cardiotoxicity (AIC). AIC has a complex pathogenesis that includes a variety of aspects such as oxidative stress, autophagy, and inflammation. Emerging evidence has strongly suggested that the loss of mitochondrial quality control (MQC) plays an important role in the progression of AIC. Mitochondria are vital organelles in the cardiomyocytes that serve as the key regulators of reactive oxygen species (ROS) production, energy metabolism, cell death, and calcium buffering. However, as mitochondria are susceptible to damage, the MQC system, including mitochondrial dynamics (fusion/fission), mitophagy, mitochondrial biogenesis, and mitochondrial protein quality control, appears to be crucial in maintaining mitochondrial homeostasis. In this review, we summarize current evidence on the role of MQC in the pathogenesis of AIC and highlight the therapeutic potential of restoring the cardiomyocyte MQC system in the prevention and intervention of AIC.

The Mitochondrial Unfolded Protein Response: A Novel Protective Pathway Targeting Cardiomyocytes

Mitochondrial protein homeostasis in cardiomyocyte injury determines not only the normal operation of mitochondrial function but also the fate of mitochondria in cardiomyocytes. Studies of mitochondrial protein homeostasis have become an integral part of cardiovascular disease research. Modulation of the mitochondrial unfolded protein response (UPRmt), a protective factor for cardiomyocyte mitochondria, may in the future become an important treatment strategy for myocardial protection in cardiovascular disease. However, because of insufficient understanding of the UPRmt and inadequate elucidation of relevant mechanisms, few therapeutic drugs targeting the UPRmt have been developed. The UPRmt maintains a series of chaperone proteins and proteases and is activated when misfolded proteins accumulate in the mitochondria. Mitochondrial injury leads to metabolic dysfunction in cardiomyocytes. This paper reviews the relationship of the UPRmt and mitochondrial quality monitoring with cardiomyocyte protection. This review mainly introduces the regulatory mechanisms of the UPRmt elucidated in recent years and the relationship between the UPRmt and mitophagy, mitochondrial fusion/fission, mitochondrial biosynthesis, and mitochondrial energy metabolism homeostasis in order to generate new ideas for the study of the mitochondrial protein homeostasis mechanisms as well as to provide a reference for the targeted drug treatment of imbalances in mitochondrial protein homeostasis following cardiomyocyte injury.

Orientin downregulating oxidative stress-mediated endoplasmic reticulum stress and mitochondrial dysfunction through AMPK/SIRT1 pathway in rat nucleus pulposus cells in vitro and attenuated intervertebral disc degeneration in vivo

Although considered as a major contributor to low back pain (LBP), intervertebral disc degeneration (IVDD) has poor medical and surgical treatments. Various studies have revealed that endoplasmic reticulum (ER) stress and extracellular matrix (ECM) degeneration play a vital role in initiating and developing the progression of IVDD. Moreover, restoration of SIRT1/AMPK was confirmed to prevent IVDD and damage via maintaining ER and extracellular homeostasis. In addition, orientin (Ori) has been shown to upregulate SIRT1. However, the effect of Ori in nucleus pulposus cells (NPCs) is not determined. Hence, in this study we aim to explore the function of Ori in IVDD pathological model. The results demonstrate that Ori treatment in vitro increased SIRT1/AMPK in NPCs, maintained ECM and ER balance and decreased oxidative stress (OS) response. Ori rescued the disordered homeostasis stimulated by tert-butyl hydroperoxide (TBHP), and its function can be inhibited by thapsigargin (TG). Compound C and EX-527, inhibitors of AMPK and SIRT1 counteracted the Ori-mediated ER stress elimination. These results confirm that Ori exerts its effects by upregulating AMPK and SIRT1. Puncture-stimulated IVDD rats were used to show that Ori attenuates the pathological development in vivo. In all, we partly unveil the underlying mechanisms of Ori in IVDD.