Mitochondrial dysfunction and mitochondrial therapies in heart failure

Unveiling mitochondrial-targeting compounds in Qishenyiqi dropping pills for heart failure treatment: An integrative UHPLC-QTOF MS and high-content imaging strategy

Mitochondrial dysfunction, a central pathogenic driver of heart failure (HF), underscores the therapeutic imperative to preserve mitochondrial homeostasis. Qishenyiqi dropping pills (QSYQ), a clinically validated traditional Chinese formulation, exhibits cardioprotective efficacy in HF; however, its mitochondrial-targeting bioactive constituents and mechanisms remain uncharacterized. Here, we integrate untargeted UHPLC-QTOF MS chemical profiling with high-content phenotypic screening across three HF cellular models-isoproterenol-induced hypertrophy, TGF-β1-driven fibrosis, and LPS-triggered inflammation-to systematically identify mitochondrial-targeting active compounds in QSYQ. Multidimensional assessment of mitochondrial function (ATP synthesis, membrane potential, reactive oxygen species flux) combined with machine learning-aided chemophenotypic mapping revealed 74 bioactive candidates from 2385 m/z signals, including novel HF-associated compounds. Crucially, pratensein-7-O-β-D-glucopyranoside (PG), a previously unreported isoflavone in QSYQ, demonstrated potent antifibrotic activity in NIH/3T3 cells via mitochondrial optimization: restoring ATP production, stabilizing membrane potential, and suppressing mtROS. This study establishes PG as a first-in-class mitochondrial homeostatic regulator within QSYQ, while advancing a phenotype-driven discovery framework that bridges traditional medicine complexity with mechanistic cardiology.

AMPK-YAP signaling pathway-mediated mitochondrial dynamics and mitophagy participate in the protective effect of silibinin on HaCaT cells under high glucose conditions

UVB irradiation and diabetes lead to skin injury. However, UVB irradiation has rarely been studied in the field of diabetes. Silibinin has a positive therapeutic effect on many diseases. Nevertheless, the inhibitory effects of silibinin on UVB-induced damage to epidermal cells under high glucose (HG) conditions have been infrequently investigated. Consequently, this study examined the protective efficacy and mechanisms of silibinin in mitigating UVB-induced apoptosis in epidermal cells cultured under HG conditions. The effects of combination of HG and UVB on mitochondrial apoptosis and pro-inflammatory factors production in human immortalized keratinocytes (HaCaT) were mitigated by silibinin. Meantime, silibinin reversed the UVB-induced imbalance of fission/fusion in HG-cultured HaCaT cells. Furthermore, UVB exposure increased ROS levels and reduced mitophagy in HaCaT cells under HG conditions; however, these effects were subsequently reversed by silibinin treatment. AMPK preserves energy balance by negatively regulating YAP. Silibinin increased the levels of p-AMPK and cytoplasmic YAP proteins in HaCaT cells subjected to HG and UVB treatment. Moreover, silibinin improved the dysfunction of mitochondrial dynamics, increased mitophagy levels, the viability and the expression of cytoplasmic YAP protein, and these effects were reversed via the application of an AMPK inhibitor (compound C). In summary, silibinin safeguarded epidermal cells from UVB-induced apoptosis under HG conditions by modulating mitochondrial dynamics and mitophagy through the AMPK-YAP signaling pathway.

Valine acts as an early biomarker and exacerbates pathological cardiac hypertrophy by impairing mitochondrial quality control

OBJECTIVE

Pathological cardiac hypertrophy is an independent risk factor for heart failure (HF). Early identification and timely treatment are crucial for significantly delaying the progression of HF.

METHODS

Targeted amino acid metabolomics and RNA sequencing (RNA-seq) were combined to explore the underlying mechanism. In vitro, H9c2 cells were stimulated with angiotensin II (Ang II) or were incubated with extra valine after Ang II stimulation. The branched chain alpha-ketoate dehydrogenase kinase (Bckdk) inhibitor 3,6-dichlorobenzo[b]thiophene-2-carboxylic acid (BT2) and rapamycin were utilized to confirm the role of the mammalian target of rapamycin complex 1 (mTORC1) signaling pathway in this process.

RESULTS

A significant accumulation of valine was detected within hypertrophic hearts from spontaneously hypertensive rats (SHR). When branched chain amino acid (BCAA) degradation was increased by BT2, the most pronounced decrease was observed in the valine level (Δ = 0.185 μmol/g, p < 0.001), and cardiac hypertrophy was ameliorated. The role of imbalanced mitochondrial quality control (MQC), including the suppression of mitophagy and excessive mitochondrial fission, was revealed in myocardial hypertrophy. In vitro, high concentrations of valine exacerbated cardiomyocyte hypertrophy stimulated by Any II, resulting in the accumulation of impaired mitochondria and respiratory chain dysfunction. BT2, rapamycin, and mitochondrial division inhibitor 1 (Mdivi-1) all ameliorated MQC imbalance, mitochondrial damage and oxidative stress in hypertensive models with high valine concentration.

CONCLUSION

Valine exacerbated pathological cardiac hypertrophy by causing a MQC imbalance, probably as an early biomarker for cardiac hypertrophy under chronic hypertension.

Fatty acid synthase inhibition offers protection against pressure-induced cardiac hypertrophy

Disturbed cardiac metabolism is an important aspect of the pathology of Cardiac hypertrophy (CH) which precede Heart failure (HF). Studies have shown a higher rate of De novo lipogenesis in HF and its inhibition has been protective. However, its role in CH still needs further clarification. For in vitro studies, Phenylephrine (PE) was used to induce CH in adult human ventricular cardiomyocytes (AC16). For in vivo studies, 2 kidney 1 clip (2K1C) and Transverse aortic constriction (TAC) models of rat were used. Fatty acid synthase (FAS), key enzyme of lipogenesis was inhibited using FAS si RNA (30 nM) and C75 (2 mg/kg, i.p. once a week for 8 weeks) in vitro and in vivo respectively. Echocardiography and histochemical staining were used to observe cardiac remodeling. Western blotting, Seahorse analysis, fluorescence microscopy and FACS were performed to detect metabolic alterations, mitochondrial dysfunction, protein synthesis and hypertrophy. We observed increased expression and activity of FAS in PE-exposed AC16 and 2K1C and TAC models of rats. Inhibition of FAS decreased hypertrophy, protein synthesis by malonylation of mTOR, apoptosis, glycolysis, and oxidative stress and restored oxidative phosphorylation in AC16 cells. In rats, FAS inhibition prevented cardiac remodelling in 2K1C and TAC models. It also increased ATP, restored mitochondrial ROS and membrane potential in the TAC model of rats. Our results demonstrated that FAS activity was modulated during CH, and inhibiting it prevented cardiac remodelling and mitochondrial dysfunctions. The findings, therefore, suggest that inhibiting FAS may be a new therapeutic approach to treating CH patients.

Chronic stress elicits sex-specific mitochondrial respiratory functional changes in the rat heart

Although chronic psychosocial stress is linked to cardiovascular diseases, the underlying mechanisms remain elusive. For this study, we focused on the mitochondrion as a putative mediator of stress-related cardiac pathologies in a sex-dependent manner. Male and female Wistar rats were subjected to chronic stress for 4 weeks (mimicking an anxious phenotype) versus matched controls. Cardiac redox status, mitochondrial respiration parameters, and expression levels of proteins involved in mitochondrial oxidative phosphorylation, dynamics, and biogenesis were evaluated. Despite limited changes in behavior and circulating stress hormones (both sexes), stressed males exhibited altered cardiac oxidative phosphorylation via β-oxidation- and glucose oxidation-linked respiratory pathways together with increased myocardial antioxidant capacity and decreased lipid peroxidation. Conversely, stressed females exhibited a protective and resilient phenotype by displaying augmented levels of major mitochondrial respiratory complexes (complex I, III, and ATP synthase) and a fusion marker (mitofusin-2 [Mfn2]), together with attenuated expression of a fission marker (dynamin-related protein-1 [Drp1]) despite decreased estradiol levels. In contrast, stressed males displayed increased cardiac ATP synthase levels together with diminished peroxisome proliferator-activated receptor-gamma coactivator-1-alpha (PGC-1α) expression versus controls. These findings indicate that male mitochondria are more prone to stress-related functional changes, while females exhibited a more protective and resilient phenotype.

Current state of heart failure treatment: are mesenchymal stem cells and their exosomes a future therapy?

Heart failure (HF) represents the terminal stage of cardiovascular disease and remains a leading cause of mortality. Epidemiological studies indicate a high prevalence and mortality rate of HF globally. Current treatment options primarily include pharmacological and non-pharmacological approaches. With the development of mesenchymal stem cell (MSC) transplantation technology, increasing research has shown that stem cell therapy and exosomes derived from these cells hold promise for repairing damaged myocardium and improving cardiac function, becoming a hot topic in clinical treatment for HF. However, this approach also presents certain limitations. This review summarizes the mechanisms of HF, current treatment strategies, and the latest progress in the application of MSCs and their exosomes in HF therapy.

Surveying the Therapeutic Potentials of Isoliquiritigenin (ISL): A Comprehensive Review

Isoliquiritigenin (ISL), a major chalcone-type flavonoid produced predominantly from liquorice roots (Glycyrrhiza species), has exceptional therapeutic potential across a wide range of pharmacological activities. ISL has numerous benefits including antioxidant, anti-inflammatory, antidiabetic, cardioprotective, hepatoprotective, neuroprotective, and anticancer activities. This review gathers the pharmacological effects of ISL remarking into its mechanism of actions such as how it modulates oxidative stress, inflammatory pathways, glucose metabolism, and cancer growth, demonstrating its pharmacological versatility. The review emphasizes new advances in the field, allowing for more rational development and clinical use of ISL in medicine. However, further research is required to confirm the target-organ toxicity or side-effect investigations.

Sotorasib-impaired degradation of NEU1 contributes to cardiac injury by inhibiting AKT signaling

Sotorasib, the inaugural targeted inhibitor sanctioned for the management of patients afflicted with locally advanced or metastatic non-small cell lung cancer presenting the KRAS G12C mutation, has encountered clinical application constraints due to its potential for cardiac injury as evidenced by safety trials. This investigation has elucidated that the heightened expression of neuraminidase-1 (NEU1) constitutes the principal etiology of cardiac damage induced by sotorasib. Mechanistically, sotorasib treatment inhibited the ubiquitinated degradation of NEU1, leading to its elevated expression, which induced downstream AKT signaling pathway inhibition and mitochondrial dysfunction leading to cardiomyocyte apoptosis. Meanwhile, in vivo and in vitro studies showed that D-pantothenic acid (D-PAC) alleviated sotorasib-induced cardiac damage by promoting NEU1 degradation. In conclusion, this study revealed that NEU1 is a key protein in sotorasib cardiotoxicity and that reducing the level of this protein is a critical strategy for the clinical treatment of sotorasib-induced cardiac injury. Schematic representation of a mechanism.

Systemic aging fuels heart failure: Molecular mechanisms and therapeutic avenues

Systemic aging influences various physiological processes and contributes to structural and functional decline in cardiac tissue. These alterations include an increased incidence of left ventricular hypertrophy, a decline in left ventricular diastolic function, left atrial dilation, atrial fibrillation, myocardial fibrosis and cardiac amyloidosis, elevating susceptibility to chronic heart failure (HF) in the elderly. Age-related cardiac dysfunction stems from prolonged exposure to genomic, epigenetic, oxidative, autophagic, inflammatory and regenerative stresses, along with the accumulation of senescent cells. Concurrently, age-related structural and functional changes in the vascular system, attributed to endothelial dysfunction, arterial stiffness, impaired angiogenesis, oxidative stress and inflammation, impose additional strain on the heart. Dysregulated mechanosignalling and impaired nitric oxide signalling play critical roles in the age-related vascular dysfunction associated with HF. Metabolic aging drives intricate shifts in glucose and lipid metabolism, leading to insulin resistance, mitochondrial dysfunction and lipid accumulation within cardiomyocytes. These alterations contribute to cardiac hypertrophy, fibrosis and impaired contractility, ultimately propelling HF. Systemic low-grade chronic inflammation, in conjunction with the senescence-associated secretory phenotype, aggravates cardiac dysfunction with age by promoting immune cell infiltration into the myocardium, fostering HF. This is further exacerbated by age-related comorbidities like coronary artery disease (CAD), atherosclerosis, hypertension, obesity, diabetes and chronic kidney disease (CKD). CAD and atherosclerosis induce myocardial ischaemia and adverse remodelling, while hypertension contributes to cardiac hypertrophy and fibrosis. Obesity-associated insulin resistance, inflammation and dyslipidaemia create a profibrotic cardiac environment, whereas diabetes-related metabolic disturbances further impair cardiac function. CKD-related fluid overload, electrolyte imbalances and uraemic toxins exacerbate HF through systemic inflammation and neurohormonal renin-angiotensin-aldosterone system (RAAS) activation. Recognizing aging as a modifiable process has opened avenues to target systemic aging in HF through both lifestyle interventions and therapeutics. Exercise, known for its antioxidant effects, can partly reverse pathological cardiac remodelling in the elderly by countering processes linked to age-related chronic HF, such as mitochondrial dysfunction, inflammation, senescence and declining cardiomyocyte regeneration. Dietary interventions such as plant-based and ketogenic diets, caloric restriction and macronutrient supplementation are instrumental in maintaining energy balance, reducing adiposity and addressing micronutrient and macronutrient imbalances associated with age-related HF. Therapeutic advancements targeting systemic aging in HF are underway. Key approaches include senomorphics and senolytics to limit senescence, antioxidants targeting mitochondrial stress, anti-inflammatory drugs like interleukin (IL)-1β inhibitors, metabolic rejuvenators such as nicotinamide riboside, resveratrol and sirtuin (SIRT) activators and autophagy enhancers like metformin and sodium-glucose cotransporter 2 (SGLT2) inhibitors, all of which offer potential for preserving cardiac function and alleviating the age-related HF burden.

Improving effect of physical exercise on heart failure: Reducing oxidative stress-induced inflammation by restoring Ca2+ homeostasis

Heart failure (HF) is associated with the occurrence of mitochondrial dysfunction. ATP produced by mitochondria through the tricarboxylic acid cycle is the main source of energy for the heart. Excessive release of Ca2+ from myocardial sarcoplasmic reticulum (SR) in HF leads to excessive Ca2+ entering mitochondria, which leads to mitochondrial dysfunction and REDOX imbalance. Excessive accumulation of ROS leads to mitochondrial structure damage, which cannot produce and provide energy. In addition, the accumulation of a large number of ROS can activate NF-κB, leading to myocardial inflammation. Energy deficit in the myocardium has long been considered to be the main mechanism connecting mitochondrial dysfunction and systolic failure. However, exercise can improve the Ca2+ imbalance in HF and restore the Ca2+ disorder in mitochondria. Similarly, exercise activates mitochondrial dynamics to improve mitochondrial function and reshape intact mitochondrial structure, rebalance mitochondrial REDOX, reduce excessive release of ROS, and rescue cardiomyocyte energy failure in HF. In this review, we summarize recent evidence that exercise can improve Ca2+ homeostasis in the SR and activate mitochondrial dynamics, improve mitochondrial function, and reduce oxidative stress levels in HF patients, thereby reducing chronic inflammation in HF patients. The improvement of mitochondrial dynamics is beneficial for ameliorating metabolic flow bottlenecks, REDOX imbalance, ROS balance, impaired mitochondrial Ca2+ homeostasis, and inflammation. Interpretation of these findings will lead to new approaches to disease mechanisms and treatment.

Mitochondrial Dysfunction in HFpEF: Potential Interventions Through Exercise

HFpEF is a prevalent and complex type of heart failure. The concurrent presence of conditions such as obesity, hypertension, hyperglycemia, and hyperlipidemia significantly increase the risk of developing HFpEF. Mitochondria, often referred to as the powerhouses of the cell, are crucial in maintaining cellular functions, including ATP production, intracellular Ca2+ regulation, reactive oxygen species generation and clearance, and the regulation of apoptosis. Exercise plays a vital role in preserving mitochondrial homeostasis, thereby protecting the cardiovascular system from acute stress, and is a fundamental component in maintaining cardiovascular health. In this study, we review the mitochondrial dysfunction underlying the development and progression of HFpEF. Given the pivotal role of exercise in modulating cardiovascular diseases, we particularly focus on exercise as a potential therapeutic strategy for improving mitochondrial function. Graphical abstract Note: This picture was created with BioRender.com.

Xin-Ji-Er-Kang balances mitochondrial fusion and fission to protect cardiomyocytes in mice with heart failure by regulating the ERα/SIRT3 pathway

BACKGROUND

Mitochondrial dynamics imbalance is an essential pathological mechanism in heart failure (HF). The Chinese herbal formula Xin-Ji-Er-Kang (XJEK) has demonstrated good therapeutic effects in various cardiovascular disease models. However, whether XJEK treats HF by regulating mitochondrial dynamics homeostasis and its specific molecular mechanisms remain elusive.

PURPOSE

To investigate the effect of XJEK on restoring the disrupted mitochondrial dynamics homeostasis in HF and elucidate the potential regulatory mechanism.

STUDY-DESIGN/METHODS

A mouse model of myocardial ischemia-reperfusion (MIR)-induced HF was established to assess the cardioprotection of XJEK. Subsequently, network pharmacology was employed to predict the mechanism by which XJEK treated HF. Moreover, gene silencing was employed to explore the potential mechanisms behind the cardioprotective effects of XJEK in AC16 cells subjected to hypoxia/reoxygenation (H/R).

RESULTS

XJEK treatment significantly attenuated myocardial fibrosis and ameliorated ventricular remodeling in post-MIR-induced HF mice. Network pharmacology analysis identified the estrogen receptor α (ERα) as a key regulator of XJEK-mediated cardioprotection. XJEK disordered mitochondrial dynamics in the hearts of MIR-induced HF mice. In addition, XJEK restored mitochondrial fusion-fission imbalance and facilitated ERα nuclear translocation to up-regulate sirtuin 3 (SIRT3) expression in the hearts of MIR-induced HF mice and H/R-induced AC16 cells. Notably, ERα depletion in cardiomyocytes completely abrogated the cardioprotective effects of XJEK.

CONCLUSION

XJEK safeguards the hearts in mice with MIR-induced HF by facilitating ERα nuclear translocation to up-regulate SIRT3 expression to rescue the mitochondrial fusion-fission imbalance. This study establishes a new theoretical basis for treating HF with XJEK.

The role of long non-coding RNAs in cardiovascular diseases: A comprehensive review

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide, posing significant challenges to healthcare systems. Despite advances in medical interventions, the molecular mechanisms underlying CVDs are not yet fully understood. For decades, protein-coding genes have been the focus of CVD research. However, recent advances in genomics have highlighted the importance of long non-coding RNAs (lncRNAs) in cardiovascular health and disease. Changes in lncRNA expression specific to tissues may result from various internal or external factors, leading to tissue damage, organ dysfunction, and disease. In this review, we provide a comprehensive discussion of the regulatory mechanisms underlying lncRNAs and their roles in the pathogenesis and progression of CVDs, such as coronary heart disease, atherosclerosis, heart failure, arrhythmias, cardiomyopathies, and diabetic cardiomyopathy, to explore their potential as therapeutic targets and diagnostic biomarkers.

The Role of Mitophagy in Cardiac Metabolic Remodeling of Heart Failure: Insights of Molecular Mechanisms and Therapeutic Prospects

Heart failure (HF) treatment remains one of the major challenges in cardiovascular disease management, and its pathogenesis requires further exploration. Cardiac metabolic remodeling is of great significance as a key pathological process in the progression of HF. The complex alterations of metabolic substrates and associated enzymes in mitochondria create a vicious cycle in HF. These changes lead to increased reactive oxygen species, altered mitochondrial Ca2+ handling, and the accumulation of fatty acids, contributing to impaired mitochondrial function. In this context, mitophagy plays a significant role in clearing damaged mitochondria, thereby maintaining mitochondrial function and preserving cardiac function by modulating metabolic remodeling in HF. This article aims to explore the role of mitophagy in cardiac metabolic remodeling in HF, especially in obesity cardiomyopathy, diabetic cardiomyopathy, and excessive afterload-induced heart failure, thoroughly analyze its molecular mechanisms, and review the therapeutic strategies and prospects based on the regulation of mitophagy.

A ROS-responsive TPP-modified tanshinone IIA micelle improves DOX-induced heart failure

OBJECTIVE

Heart failure (HF) is a prevalent, refractory, and costly medical condition. As most current strategies have failed to yield beneficial clinical outcomes, microenvironment-responsive micelles have been developed to target cardiomyocyte mitochondria to improve HF.

METHODS

In this paper, we constructed reactive oxygen species (ROS)-responsive triphenylphosphine (TPP)-modified tanshinone IIA (TIIA) micelles (TK-TPP-TIIA@Ms). TIIA was encapsulated within the micelles and utilized TPP-conjugated DSPE-PEG2000 as the targeting molecule and ROS-responsive bond TK as the linker arm connecting DSPE-PEG5000. The formation of a hydrated membrane on the micelle surface prolonged micelle circulation while preventing active targeting molecules from binding to the mitochondria of normal cardiomyocytes throughout the body, which reduced drug accumulation in healthy tissues. In the HF microenvironment, TK was cleaved by overexpressed ROS, which led to the shedding of the PEG5000 hydration layer and the subsequent exposure of the target ligand TPP. This process facilitated TPP uptake by activated cardiomyocyte mitochondria and exerted anti-HF effects. Furthermore, in vivo and in vitro experiments were conducted to verify its effect on improving doxorubicin (DOX)-induced HF, which focused on oxidative stress, apoptosis, and inflammation.

RESULTS

TK-TPP-TIIA@Ms was successfully prepared and exhibited normal appearance and morphology, appropriate particle size, and zeta potential; and demonstrated good encapsulation efficiency, drug loading, and biological safety. In vitro studies showed that TK-TPP-TIIA@Ms had strong uptake ability in H9c2 cells, which led to reduced DOX-induced ROS expression, decreased secretion of inflammatory factors, inhibition of cell apoptosis, and restoration of normal mitochondrial membrane potential. In vivo, TK-TPP-TIIA@Ms effectively ameliorated DOX-induced myocardial tissue damage, reduced cell apoptosis, decreased the expression of inflammatory factors, and improved oxidative stress, which inhibited DOX-induced HF in mice.

CONCLUSION

TK-TPP-TIIA@Ms is an effective and safe strategy for the targeted therapy of heart diseases and is expected to become a potential treatment for heart failure.

Mitochondrial quality control: Biochemical mechanism of cardiovascular disease

Mitochondria play a key role in the regulation of energy homeostasis and ATP production in cardiac cells. Mitochondrial dysfunction can trigger several pathological events that contribute to the development and progression of cardiovascular diseases. These mechanisms include the induction of oxidative stress, dysregulation of intracellular calcium cycling, activation of the apoptotic pathway, and alteration of lipid metabolism. This review focuses on the role of mitochondria in intracellular signaling associated with cardiovascular diseases, emphasizing the contributions of reactive oxygen species production and mitochondrial dynamics. Indeed, mitochondrial dysfunction has been implicated in every aspect of cardiovascular disease and is currently being evaluated as a potential target for therapeutic interventions. To treat cardiovascular diseases and improve overall heart health, it is important to better understand these biochemical systems. These findings allow the achievement of targeted therapies and preventive measures. Therefore, this review investigates different studies that demonstrate how changes in mitochondrial dynamics like fusion, fission, and mitophagy contribute to the development or worsening of disorders related to heart diseases by summarizing current research on their role.

Proteomic analysis reveals QiShenYiQi Pills ameliorates ischemia-induced heart failure through inhibition of mitochondrial fission

BACKGROUND

QiShenYiQi Pills (QSYQ) has widely used in clinical treatment of cardiovascular diseases; however, the exact mechanism behind its effectiveness still requires further investigation.

PURPOSE

The purpose of the study was to explore the potential mechanism of QSYQ in the treatment of ischemic heart failure from the perspective of proteomics.

METHODS

In vivo, to observe QSYQ actions on the progression of ischemia-induced heart failure, cardiac function and remodeling was analyzed. The heart tissues of mice were used for Tandem Mass Tag (TMT)-based proteomic analysis. Cardiomyocytes were prepared and subjected to oxygen-glucose deprivation injury. QSYQ effects on differential proteins expressions, mitochondrial fission and mitochondrial function were assayed.

RESULTS

QSYQ treatment preserved cardiac function, limited cardiac fibrosis and alleviated cardiomyocyte hypertrophy in post-myocardial ischemia mice. Proteomic analysis revealed that QSYQ-responsive proteins were mainly involved in mitochondrial fission, including mitochondrial calcium uniporter (MCU), membrane associated ring-CH-type finger 5 (MARCHF5), and mitochondrial fission process 1 (MTFP1). Protein-protein interaction analysis revealed that MCU, MARCHF5 and MTFP1 commonly interacted with dynamin-related protein 1 (DRP1). Knockdown of MCU, MARCHF5, or MTFP1 attenuated excessive mitochondrial fission in cardiomyocytes through regulating DRP1 phosphorylation and its mitochondrial translocation. QSYQ decreased the phosphorylation of DRP1 at Ser616 and enhanced its inhibitory phosphorylation at Ser637, as well as mitigating the mitochondrial recruitment and oligomerization of DRP1, through downregulation of these three differential proteins. As a result, QSYQ alleviated aberrant mitochondrial fission, ameliorated mitochondrial dysfunction, and protected cardiomyocytes from ischemic injury.

CONCLUSION

The novelty lies in the proteomics-based investigation of the mechanism of QSYQ, uncovering that QSYQ mitigated ischemia-induced heart failure by suppressing MCU/MARCHF5/MTFP1-DRP1-driven mitochondrial fission.

Uncovering the active ingredients of Xinbao pill against chronic heart failure: A chemical profiling, pharmacokinetics and pharmacodynamics integrated study

ETHNOPHARMACOLOGICAL RELEVANCE

Xinbao pill (XBP) is a renowned Chinese patent medicine, primarily efficacious in warming and nourishing the heart and kidneys, supplementing Qi to boost Yang, and promoting blood circulation to remove blood stasis. XBP has been utilized for the treatment of chronic heart failure (CHF) for nearly 30 years, but the lack of clarity regarding the active ingredients of XBP against CHF has hindered its clinical application and further promotion.

AIM OF THE STUDY

To comprehensively elucidate the efficacy-specific ingredients and potential mechanism of XBP against CHF.

METHODS

The efficacy, chemical profiling and pharmacokinetics of XBP was assessed in a CHF model rat. The anti-CHF mechanism of the mixture of the likely active ingredients was clarified by targeted metabolomics and western blotting analysis.

RESULTS

XBP alleviated CHF by enhancing cardiac function, reducing NT-pro BNP, mitigating myocardial damage and degrading extracellular collagen. Following XBP administration, ginsenosides exposed relatively abundant in sham or CHF rats. Ginsenoside Rg1 and notoginsenoside R1 showed downward trends in AUC0-t values in CHF group, accompanied by increasing trends in CL/F values. Moreover, CHF rats presented significantly elevated levels of ginsenoside Rg1, ginsenoside Rg2 and notoginsenoside R1 in heart. The mixture of ginsenoside Rg1, ginsenoside Rg2 and notoginsenoside R1 demonstrated remarkable efficacy in ameliorating CHF as XBP did. Notably, these three compounds were predominantly localized in mitochondria and exhibited significant potential to enhance mitochondrial homeostasis by inhibiting heme synthesis pathway-mediated decomposition of succinyl CoA.

CONCLUSIONS

Our research provides valuable insights that ginsenoside Rg1, ginsenoside Rg2 and notoginsenoside R1 may constitute the anti-CHF active ingredients of XBP for facilitating mitochondrial homeostasis by the suppression of heme synthesis to increase succinyl CoA.

Total Area of Interfibrillar Mitochondria in the Right Atrial Appendage Cardiomyocytes as an Index of the Functional State of the Cardiovascular System in Chronic Heart Failure

The clinical significance of the total area of mitochondria index in the right atrial appendage cardiomyocytes was evaluated. The index was calculated as the ratio of the total area of interfibrillar mitochondria to the area of the interfibrillar space (SMT/SIFS). A total of 39 micrographs of cardiomyocytes from 12 patients with heart failure (left ventricular ejection fraction LV EF<50%) and with obstructive multivessel coronary artery disease were analyzed. The results of the electron microscopy study were compared with the main echocardiography parameters and the functional status of the patients. It was found that the computed SMT/SIFS index was associated with general functional status according to the 6-min walk and cardiopulmonary exercise tests.

Advances in the activity of resveratrol and its derivatives in cardiovascular diseases

Cardiovascular diseases (CVDs), the leading cause of human death worldwide, are diseases that affect the heart and blood vessels and include arrhythmias, coronary atherosclerotic heart disease, hypertension, and so on. Resveratrol (RSV) is a natural nonflavonoid phenolic compound with antioxidant, anti-inflammatory, anticancer, and cardiovascular protection functions. RSV has shown significant protective effects against CVD. However, RSV's clinical application is limited by its tendency to be oxidized and metabolized easily. Therefore, it is necessary to optimize the RSV structure. This review will introduce the activity, synthesis, and structure-activity relationships of RSV derivatives, and the mechanism of the action of RSV in CVDs in recent years.

Mitochondrial apoptosis in response to cardiac ischemia-reperfusion injury

In patients with acute myocardial infarction (AMI), thrombolytic therapy and revascularization strategies allow complete recanalization of occluded epicardial coronary arteries. However, approximately 35% of patients still experience myocardial ischemia/reperfusion (I/R) injury, which contributing to increased AMI mortality. Therefore, an accurate understanding of myocardial I/R injury is important for preventing and treating AMI. The death of each cell (cardiomyocytes, endothelial cells, vascular smooth muscle cells, cardiac fibroblasts, and mesenchymal stem cells) after myocardial ischemia/reperfusion is associated with apoptosis due to mitochondrial dysfunction. Abnormal opening of the mitochondrial permeability transition pore, aberrant mitochondrial membrane potential, Ca2+ overload, mitochondrial fission, and mitophagy can lead to mitochondrial dysfunction, thereby inducing mitochondrial apoptosis. The manifestation of mitochondrial apoptosis varies according to cell type. Here, we reviewed the characteristics of mitochondrial apoptosis in cardiomyocytes, endothelial cells, vascular smooth muscle cells, cardiac fibroblasts, and mesenchymal stem cells following myocardial ischemia/reperfusion.

Shenmai injection revives cardiac function in rats with hypertensive heart failure: involvement of microbial-host co-metabolism

Heart failure (HF) is a complex syndrome marked by considerable expenditures and elevated mortality and morbidity rates globally. Shenmai injection (SMI), a form of Traditional Chinese Medicine-based therapy, has demonstrated effectiveness in treating HF. Recent research suggests that Traditional Chinese Medicine (TCM) may induce beneficial changes in microbial-host co-metabolism, potentially providing cardiovascular protection. This study used a rat model of hypertensive heart failure (H-HF) to explore the mechanism of SMI. The possible compounds and key targets of SMI against H-HF were investigated using network pharmacology. The pharmacodynamics of SMI were validated using the H-HF animal model, with analysis of fecal gut microbiota integrating metabolomics and 16S rRNA sequencing. Metorigin metabolite traceability analysis and the MetaboAnalyst platform were utilized to explore the action mechanism. To evaluate changes in serum TMAO levels, targeted metabolomics was performed. Finally, the study looked at the intrinsic relationships among modifications in the intestinal flora, metabolite profile changes, and the targets of SMI compounds to clarify how they might be used to treat H-HF. According to metabolomics and 16S rRNA sequencing, by reestablishing homeostasis in the gut microbiota, SMI affects vital metabolic pathways, such as energy metabolism, amino acid metabolism, and bile acid metabolism. Increased serum TMAO levels were identified to be a risk factor for H-HF, and SMI was able to downregulate the levels of TMAO-related metabolites. Network pharmacology analysis identified 13 active components of SMI targeting 46 proteins, resulting in differential expression changes in 8 metabolites and 24 gut microbes. In conclusion, this study highlights the effectiveness of SMI in alleviating H-HF and its potential to modulate microbial-host co-metabolism. Through a comprehensive discussion of the interconnected relationships among the components, targets, metabolites, and gut microbiota, it provided fresh light on the therapeutic mechanism of SMI on H-HF.

Elamipretide: A Review of Its Structure, Mechanism of Action, and Therapeutic Potential

Mitochondria serve an essential metabolic and energetic role in cellular activity, and their dysfunction has been implicated in a wide range of disorders, including cardiovascular conditions, neurodegenerative disorders, and metabolic syndromes. Mitochondria-targeted therapies, such as Elamipretide (SS-31, MTP-131, Bendavia), have consequently emerged as a topic of scientific and clinical interest. Elamipretide has a unique structure allowing for uptake in a variety of cell types and highly selective mitochondrial targeting. This mitochondria-targeting tetrapeptide selectively binds cardiolipin (CL), a lipid found in the inner mitochondrial membrane, thus stabilizing mitochondrial cristae structure, reducing oxidative stress, and enhancing adenosine triphosphate (ATP) production. Preclinical studies have demonstrated the protective and restorative efficacy of Elamipretide in models of heart failure, neurodegeneration, ischemia-reperfusion injury, metabolic syndromes, and muscle atrophy and weakness. Clinical trials such as PROGRESS-HF, TAZPOWER, MMPOWER-3, and ReCLAIM elaborate on preclinical findings and highlight the significant therapeutic potential of Elamipretide. Further research may expand its application to other diseases involving mitochondrial dysfunction as well as investigate long-term efficacy and safety of the drug. The following review synthesizes current knowledge of the structure, mechanisms of action, and the promising therapeutic role of Elamipretide in stabilizing mitochondrial fitness, improving mitochondrial bioenergetics, and minimizing oxidative stress.

Nerol attenuates doxorubicin-induced heart failure by inhibiting cardiomyocyte apoptosis in rats

BACKGROUND

As a broad-spectrum anti-tumour drug, the clinical application of DOX is often limited owing to its cardiotoxicity. Nerol is a naturally occurring compound with both anti-inflammatory and antioxidant properties. However, the ability of Nerol to improve DOX-induced heart failure and its underlying mechanisms remain unclear.

METHODS

Rat models of DOX-induced heart failure were established and rats were treated with various doses of Nerol. Apoptosis in cardiomyocytes was detected using TUNEL staining and the expression levels of apoptosis-related proteins were detected using western blotting and immunofluorescence. In addition, mitochondrial structure was observed using electron microscopy, mitochondrial membrane potential was detected using a JC-1 fluorescent probe, and superoxide dismutase were detected to comprehensively evaluate the regulatory effect of Nerol on mitochondrial function and oxidative stress.

RESULTS

Analysis showed that the number of apoptotic cardiomyocytes was significantly reduced after Nerol treatment, accompanied by the downregulation of Bax protein expression and upregulation of Bcl-2 protein expression, suggesting that Nerol may inhibit the apoptotic process of cardiomyocytes by regulating the balance of Bcl-2 family proteins. In addition, the mitochondrial function of Nerol-treated rats was protected, as indicated by the stability of the mitochondrial membrane potential, integrity of mitochondrial morphology. These changes suggest that Nerol may reduce the severity of heart failure by improving mitochondrial function.

CONCLUSIONS

Nerol plays a positive role in alleviating DOX-induced heart failure in rats, possibly by inhibiting cardiomyocyte apoptosis. These findings provide novel evidence and potential targets for developing new cardioprotective drugs.

Identification of a mitophagy-related gene signature for predicting overall survival and response to immunotherapy in rectal cancer

BACKGROUND

Rectal cancer is a highly heterogeneous gastrointestinal tumor, and the prognosis for patients with treatment-resistant and metastatic rectal cancer remains poor. Mitophagy, a type of selective autophagy that targets mitochondria, plays a role in promoting or inhibiting tumors; however, the importance of mitophagy-related genes (MRGs) in the prognosis and treatment of rectal cancer is unclear.

METHODS

In this study, we used the differentially expressed genes (DEGs) and MRGs from the TCGA-READ dataset to identify differentially expressed mitophagy-related genes (MRDEGs). The mitophagy scores were then analyzed for differential expression and ROC. Seven module genes were identified using the weighted gene coexpression network analysis (WGCNA) approach and subsequently validated in the merged datasets GSE87211 and GSE90627. The model genes were obtained based on prognostic features, and the subgroups were distinguished by risk score. Gene enrichment, immune infiltration and immunotherapy response were also evaluated. Finally, validation of prognostic gene expression in rectal cancer was carried out using clinical samples, employing Immunohistochemistry (IHC).

RESULTS

We demonstrated that 22 MRGs were differentially expressed between normal and rectal cancer tissues. A prognostic model for rectal cancer MRGs was constructed using WGCNA and Cox regression, which exhibited good diagnostic performance. In this study, we identified four molecular markers (MYLK, FLNC, MYH11, and NEXN) as potential prognostic biomarkers for rectal cancer for the first time. Moreover, our findings indicate that the risk scores derived from the four MRGs are associated with tumor immunity. To further validate our findings, IHC analyses suggested that the expression of MYH11 in rectal cancer tissues was lower than in nontumorous rectal tissues.

CONCLUSION

MRGs could predict the prognosis and response to immunotherapy in patients with rectal cancer and might be able to personalize treatment for patients.

Deciphering Oxidative Stress in Cardiovascular Disease Progression: A Blueprint for Mechanistic Understanding and Therapeutic Innovation

Oxidative stress plays a pivotal role in the pathogenesis and progression of cardiovascular diseases (CVDs). This review focuses on the signaling pathways of oxidative stress during the development of CVDs, delving into the molecular regulatory networks underlying oxidative stress in various disease stages, particularly apoptosis, inflammation, fibrosis, and metabolic imbalance. By examining the dual roles of oxidative stress and the influences of sex differences on oxidative stress levels and cardiovascular disease susceptibility, this study offers a comprehensive understanding of the pathogenesis of cardiovascular diseases. The study integrates key findings from current research in three comprehensive ways. First, it outlines the major CVDs associated with oxidative stress and their respective signaling pathways, emphasizing oxidative stress's central role in cardiovascular pathology. Second, it summarizes the cardiovascular protective effects, mechanisms of action, and animal models of various antioxidants, offering insights into future drug development. Third, it discusses the applications, advantages, limitations, and potential molecular targets of gene therapy in CVDs, providing a foundation for novel therapeutic strategies. These tables underscore the systematic and integrative nature of this study while offering a theoretical basis for precision treatment for CVDs. A major contribution of this study is the systematic review of the differential effects of oxidative stress across different stages of CVDs, in addition to the proposal of innovative, multi-level intervention strategies, which open new avenues for precision treatment of the cardiovascular system.

Mitophagy in ischemic heart disease: molecular mechanisms and clinical management

The influence of the mitochondrial control system on ischemic heart disease has become a major focus of current research. Mitophagy, as a very crucial part of the mitochondrial control system, plays a special role in ischemic heart disease, unlike mitochondrial dynamics. The published reviews have not explored in detail the unique function of mitophagy in ischemic heart disease, therefore, the aim of this paper is to summarize how mitophagy regulates the progression of ischemic heart disease. We conclude that mitophagy affects ischemic heart disease by promoting cardiomyocyte hypertrophy and fibrosis, the progression of oxidative stress, the development of inflammation, and cardiomyocyte death, and that the specific mechanisms of mitophagy are worthy of further investigation.

Nrf2/NRF1 signaling activation and crosstalk amplify mitochondrial biogenesis in the treatment of triptolide-induced cardiotoxicity using calycosin

Nuclear factor erythroid 2-related factor 2 (Nrf2) regulates both oxidative stress and mitochondrial biogenesis. Our previous study reported the cardioprotection of calycosin against triptolide toxicity through promoting mitochondrial biogenesis by activating nuclear respiratory factor 1 (NRF1), a coregulatory effect contributed by Nrf2 was not fully elucidated. This work aimed at investigating the involvement of Nrf2 in mitochondrial protection and elucidating Nrf2/NRF1 signaling crosstalk on amplifying the detoxification of calycosin. Results indicated that calycosin inhibited cardiomyocytes apoptosis and F-actin depolymerization following triptolide exposure. Cardiac contraction was improved by calycosin through increasing both fractional shortening (FS%) and ejection fraction (EF%). This enhanced contractile capacity of heart was benefited from mitochondrial protection reflected by ultrastructure improvement, augment in mitochondrial mass and ATP production. NRF1 overexpression in cardiomyocytes increased mitochondrial mass and DNA copy number, whereas NRF1 knockdown mitigated calycosin-mediated enhancement in mitochondrial mass. For nuclear Nrf2, it was upregulated by calycosin in a way of disrupting Nrf2-Keap1 (Kelch-like ECH associated protein 1) interaction, followed by inhibiting ubiquitination and degradation. The involvement of Nrf2 in mitochondrial protection was validated by the results that both Nrf2 knockdown and Nrf2 inhibitor blocked the calycosin effects on mitochondrial biogenesis and respiration. In the case of calycosin treatment, its effect on NRF1 and Nrf2 upregulations were respectively blocked by PGCα/Nrf2 and NRF1 knockdown, indicative of the mutual regulation between Nrf2 and NRF1. Accordingly, calycosin activated Nrf2/NRF1 and the signaling crosstalk, leading to mitochondrial biogenesis amplification, which would become a novel mechanism of calycosin against triptolide-induced cardiotoxicity.

Impact of Exercise on Physiological, Biochemical, and Analytical Parameters in Patients with Heart Failure with Reduced Ejection Fraction

Heart failure with reduced ejection fraction (HFrEF) is a condition marked by diminished cardiac output and impaired oxygen delivery to tissues. Exercise, once avoided in HFrEF patients due to safety concerns, is now recognized as an important therapeutic intervention. Structured exercise improves various physiological, biochemical, and analytical parameters, including cardiac output, endothelial function, skeletal muscle performance, and autonomic regulation. Biochemically, exercise induces favorable changes in inflammatory markers, lipid profiles, glucose metabolism, and renal function. This paper reviews these changes, highlighting how exercise can be safely incorporated into HFrEF management. Further research is needed to tailor exercise interventions for individual patients to optimize outcomes.

Heme Oxygenase-1 Overexpression Activates the IRF1/DRP1 Signaling Pathway to Promote M2-Type Polarization of Spinal Cord Microglia

Microglia-mediated neuroinflammatory responses have a critical function in the spinal cord injury (SCI) mechanism, and targeted modulation of microglia activity has emerged as a new therapeutic strategy for SCI. Heme oxygenase 1(HO-1) regulates the close dynamic crosstalk between oxidative stress and inflammatory responses. This investigation aimed to study the molecular pathways by which HO-1 regulates the inflammatory response of microglia. We cultivated primary rat spinal cord microglia and BV2 cell lines and used lipopolysaccharide (LPS) to stimulate microglia to establish an in vitro model. The adeno-associated virus (AAV) was used to induce HO-1 overexpression to observe the effects of HO-1 overexpression on microglia survival, morphological changes, microglia activation, inflammatory cytokines secretion, mitochondrial dynamics, and nucleotide-binding oligomerization domain-like receptor protein (NLRP3) inflammatory complex and nuclear factor-κB (NF-κB) signaling pathways. It was found that HO-1 overexpression was successfully induced using an AAV on microglia in vitro. HO-1 overexpression increased microglia survival and reduced microglia apoptosis in the inflammatory microenvironment. Overexpressed HO-1 inhibited microglia M1-type polarization, downregulated the NF-κB signaling pathway, inhibited NLRP3 inflammatory complex activation, and reduced the secretion of inflammatory factors. Overexpressed HO-1 maintained the stability of mitochondrial dynamics and inhibited excessive mitochondrial cleavage. Further experiments showed that overexpression of HO-1 activated the interferon regulatory factor 1 (IRF1)/dynamin-related protein 1 (DRP1) signaling pathway, thereby promoting microglia M2-type polarization and improving neuronal survival. This study demonstrates that HO-1 activates the IRF1/DRP1 axis, promoting M2 polarization in microglia and attenuating neuroinflammation by suppressing the NF-κB signaling pathway. These outcomes offer new visions and important clues for effectively managing SCI in the clinic.

Left Ventricular Remodeling Predictors in Chronic Heart Failure of Ischemic Etiology

Aim      To identify metabolomic and structure and function markers of remote left ventricular (LV) remodeling in patients with chronic heart failure (CHF) of ischemic etiology and LV ejection fraction (EF) <50%.Material and methods  This prospective study included 56 patients with 3-4 NYHA functional class CHF of ischemic etiology (mean age, 66±7 years) and 50 patients with ischemic heart disease (IHD) without signs of CHF (69 [64; 73.7] years). Concentration of 19 amino acids, 11 products of kynurenine catabolism of tryptophan, 30 acylcarnitines with different chain lengths were measured in all participants. The metabolites that showed statistical differences between the comparison groups were then used for the analysis. Echocardiography was used to assess LV cavity remodeling at the time of the CHF patient inclusion in the study and after 6 months of follow-up. Predictors of long-term LV cavity remodeling were assessed for this cohort taking into account statistically significant echocardiographic parameters and metabolites.Results Patients with CHF of ischemic etiology, predominantly (81%) had pathological calculated types of LV remodeling (concentric and eccentric hypertrophy, 46 and 35%, respectively). However, this classification had limitations in describing this cohort. In addition, in this group, the concentrations of alanine, proline, asparagine, glycine, arginine, histidine, lysine, valine, indolyl-3-acetic acid, indolyl-3-propionic acid, C16-1-OH, and C16-OH were significantly (p<0.05) lower, and the concentrations of most medium- and long-chain acylcarnitines were higher than in patients with IHD without signs of CHF. The long-term (6 months) reverse remodeling of the LV cavity in CHF of ischemic etiology was influenced by changes in the interventricular septum thickness (hazard ratio, HR, 19.07; 95% confidence interval, CI, 1.76-206.8; p=0.006) and concentrations of anthranilic acid (HR 19.8; 95% CI 1.01-387.8; p=0.019) and asparagine (HR 8.76; 95% CI 1.07-71.4; p=0.031).Conclusion      The presence of an interventricular septum thickness of more than 13.5 mm, anthranilic acid concentrations of higher than 0.235 μM/l, or an asparagine concentration of less than 135.2 μM/l in patients with CHF of ischemic etiology after 6 months of follow-up affects their achievement of LV cavity reverse remodeling.

Mitochondrial Dysfunction in Cardiac Disease: The Fort Fell

Myocardial cells and the extracellular matrix achieve their functions through the availability of energy. In fact, the mechanical and electrical properties of the heart are heavily dependent on the balance between energy production and consumption. The energy produced is utilized in various forms, including kinetic, dynamic, and thermal energy. Although total energy remains nearly constant, the contribution of each form changes over time. Thermal energy increases, while dynamic and kinetic energy decrease, ultimately becoming insufficient to adequately support cardiac function. As a result, toxic byproducts, unfolded or misfolded proteins, free radicals, and other harmful substances accumulate within the myocardium. This leads to the failure of crucial processes such as myocardial contraction-relaxation coupling, ion exchange, cell growth, and regulation of apoptosis and necrosis. Consequently, both the micro- and macro-architecture of the heart are altered. Energy production and consumption depend on the heart's metabolic resources and the functional state of the cardiac structure, including cardiomyocytes, non-cardiomyocyte cells, and their metabolic and energetic behavior. Mitochondria, which are intracellular organelles that produce more than 95% of ATP, play a critical role in fulfilling all these requirements. Therefore, it is essential to gain a deeper understanding of their anatomy, function, and homeostatic properties.

Interplay of Reactive Oxygen Species (ROS) and Epigenetic Remodelling in Cardiovascular Diseases Pathogenesis: A Contemporary Perspective

Cardiovascular diseases (CVDs) continue to be the leading cause of mortality worldwide, necessitating the development of novel therapies. Despite therapeutic advancements, the underlying mechanisms remain elusive. Reactive oxygen species (ROS) show detrimental effects at high concentrations but act as essential signalling molecules at physiological levels, playing a critical role in the pathophysiology of CVD. However, the link between pathologically elevated ROS and CVDs pathogenesis remains poorly understood. Recent research has highlighted the remodelling of the epigenetic landscape as a crucial factor in CVD pathologies. Epigenetic changes encompass alterations in DNA methylation, post-translational histone modifications, adenosine triphosphate (ATP)-dependent chromatin modifications, and noncoding RNA transcripts. Unravelling the intricate link between ROS and epigenetic changes in CVD is challenging due to the complexity of epigenetic signals in gene regulation. This review aims to provide insights into the role of ROS in modulating the epigenetic landscape within the cardiovascular system. Understanding these interactions may offer novel therapeutic strategies for managing CVD by targeting ROS-induced epigenetic changes. It has been widely accepted that epigenetic modifications are established during development and remain fixed once the lineage-specific gene expression pattern is achieved. However, emerging evidence has unveiled its remarkable dynamism. Consequently, it is now increasingly recognized that epigenetic modifications may serve as a crucial link between ROS and the underlying mechanisms implicated in CVD.

Orosomucoid 2 is an endogenous regulator of neuronal mitochondrial biogenesis and promotes functional recovery post-stroke

Development of functional recovery therapies is critical to reduce the global impact of stroke as the leading cause of long-term disability. Our previous studies found that acute-phase protein orosomucoid (ORM) could provide an up to 6 h therapeutic time window to reduce infarct volume in acute ischemic stroke by improving endothelial function. However, its role in neurons and functional recovery post-stroke remains largely unknown. Here, we showed that exogenous ORM administration with initial injection at 0.5 h (early) or 12 h (delayed) post-MCAO daily for consecutive 7 days significantly decreased infarct area, improved motor and cognitive functional recovery, and promoted mitochondrial biogenesis after MCAO. While neuron-specific knockout of ORM2, a dominant subtype of ORM in the brain, produced opposite effects which could be rescued by exogenous ORM. In vitro, exogenous ORM protected SH-SY5Y cells from OGD-induced damage and promoted mitochondrial biogenesis, while endogenous ORM2 deficiency worsened these processes. Mechanistically, inactivation of CCR5 or AMPK eliminated the protective effects of ORM on neuronal damage and mitochondrial biogenesis. Taken together, our findings demonstrate that ORM, mainly ORM2, is an endogenous regulator of neuronal mitochondrial biogenesis by activating CCR5/AMPK signaling pathway, and might act as a potential therapeutic target for the functional recovery post-stroke.

Don´t give up on mitochondria as a target for the treatment of diabetes and its complications

In this editorial, we discuss an article by Wang et al, focusing on the role of mitochondria in peripheral insulin resistance and insulin secretion. Despite numerous in vitro and pre-clinical studies supporting the involvement of mitochondrial dysfunction and oxidative stress in the pathogenesis of diabetes and its complications, efforts to target mitochondria for glycemic control in diabetes using mitochondria-targeted antioxidants have produced inconsistent results. The intricate functionality of mitochondria is summarized to underscore the challenges it poses as a therapeutic target. While mitochondria-targeted antioxidants have demonstrated improvement in mitochondrial function and oxidative stress in pre-clinical diabetes models, the results regarding glycemic control have been mixed, and no studies have evaluated their hypoglycemic effects in diabetic patients. Nonetheless, pre-clinical trials have shown promising outcomes in ameliorating diabetes-related complications. Here, we review some reasons why mitochondria-targeted antioxidants may not function effectively in the context of mitochondrial dysfunction. We also highlight several alternative approaches under development that may enhance the targeting of mitochondria for diabetes treatment.

SGK3 deficiency in macrophages suppresses angiotensin II-induced cardiac remodeling via regulating Ndufa13-mediated mitochondrial oxidative stress

Infiltration of monocyte-derived macrophages plays a crucial role in cardiac remodeling and dysfunction. The serum and glucocorticoid-inducible protein kinase 3 (SGK3) is a downstream factor of PI3K signaling, regulating various biological processes via an AKT-independent signaling pathway. SGK3 has been implicated in cardiac remodeling. However, the contribution of macrophagic SGK3 to hypertensive cardiac remodeling remains unclear. A cardiac remodeling model was established by angiotensin II (Ang II) infusion in SGK3-Lyz2-CRE (f/f, +) and wild-type mice to assess the function of macrophagic SGK3. Additionally, a co-culture system of SGK3-deficient or wild-type macrophages and neonatal rat cardiomyocytes (CMs) or neonatal rat fibroblasts (CFs) was established to evaluate the effects of SGK3 and the underlying mechanisms. SGK3 levels were significantly elevated in both peripheral blood mononuclear cells and serum from patients with heart failure. Macrophage SGK3 deficiency attenuated Ang II-induced macrophage infiltration, myocardial hypertrophy, myocardial fibrosis, and mitochondrial oxidative stress. RNA sequencing suggested Ndufa13 as the candidate gene in the effect of SGK3 on Ang II-induced cardiac remolding. Downregulation of Ndufa13 in CMs and CFs prevented the suppression of cardiac remodeling caused by SGK3 deficiency in macrophages. Mechanistically, the absence of SGK3 led to a reduction in IL-1β secretion by inhibiting the NLRP3/Caspase-1/IL-1β pathway in macrophages, consequently suppressing upregulated Ndufa13 expression and mitochondrial oxidative stress in CMs and CFs. This study provides new evidence that SGK3 is a potent contributor to the pathogenesis of hypertensive cardiac remodeling, and targeting SGK3 in macrophages may serve as a potential therapy for cardiac remodeling.

Xinyang tablet alleviated cardiac dysfunction in a cardiac pressure overload model by regulating the receptor-interacting serum/three-protein kinase 3/FUN14 domain containing 1-mediated mitochondrial unfolded protein response and mitophagy

ETHNOPHARMACOLOGICAL RELEVANCE

Xinyang tablet (XYT) has been used for heart failure (HF) for over twenty years in clinical practice, but the underlying molecular mechanism remains poorly understood.

AIMS OF THE STUDY

In the present study, we aimed to explore the protective effects of XYT in HF in vivo and in vitro.

MATERIALS AND METHODS

Transverse aortic constriction was performed in vivo to establish a mouse model of cardiac pressure overload. Echocardiography, tissue staining, and real-time quantitative PCR (qPCR) were examined to evaluate the protective effects of XYT on cardiac function and structure. Adenosine 5'-triphosphate production, reactive oxygen species staining, and measurement of malondialdehyde and superoxide dismutase was used to detect mitochondrial damage. Mitochondrial ultrastructure was observed by transmission electron microscope. Immunofluorescence staining, qPCR, and Western blotting were performed to evaluate the effect of XYT on the mitochondrial unfolded protein response and mitophagy, and to identify its potential pharmacological mechanism. In vitro, HL-1 cells and neonatal mouse cardiomyocytes were stimulated with Angiotensin II to establish the cell model. Western blotting, qPCR, immunofluorescence staining, and flow cytometry were utilized to determine the effects of XYT on cardiomyocytes. HL-1 cells overexpressing receptor-interacting serum/three-protein kinase 3 (RIPK3) were generated by transfection of RIPK3-overexpressing lentiviral vectors. Cells were then co-treated with XYT to determine the molecular mechanisms.

RESULTS

In the present study, XYT was found to exerta protective effect on cardiac function and structure in the pressure overload mice. And it was also found XYT reduced mitochondrial damage by enhancing mitochondrial unfolded protein response and restoring mitophagy. Further studies showed that XYT achieved its cardioprotective role through regulating the RIPK3/FUN14 domain containing 1 (FUNDC1) signaling. Moreover, the overexpression of RIPK3 successfully reversed the XYT-induced protective effects and significantly attenuated the positive effects on the mitochondrial unfolded protein response and mitophagy.

CONCLUSIONS

Our findings indicated that XYT prevented pressure overload-induced HF through regulating the RIPK3/FUNDC1-mediated mitochondrial unfolded protein response and mitophagy. The information gained from this study provides a potential strategy for attenuating mitochondrial damage in the context of pressure overload-induced heart failure using XYT.

The function and therapeutic potential of transfer RNA-derived small RNAs in cardiovascular diseases: A review

Transfer RNA-derived small RNAs (tsRNAs) are a class of small non-coding RNA (sncRNA) molecules derived from tRNA, including tRNA derived fragments (tRFs) and tRNA halfs (tiRNAs). tsRNAs can affect cell functions by participating in gene expression regulation, translation regulation, intercellular signal transduction, and immune response. They have been shown to play an important role in various human diseases, including cardiovascular diseases (CVDs). Targeted regulation of tsRNAs expression can affect the progression of CVDs. The tsRNAs induced by pathological conditions can be detected when released into the extracellular, giving them enormous potential as disease biomarkers. Here, we review the biogenesis, degradation process and related functional mechanisms of tsRNAs, and discuss the research progress and application prospects of tsRNAs in different CVDs, to provide a new perspective on the treatment of CVDs.

Mitochondrial Structure and Function in Human Heart Failure

Despite clinical and scientific advancements, heart failure is the major cause of morbidity and mortality worldwide. Both mitochondrial dysfunction and inflammation contribute to the development and progression of heart failure. Although inflammation is crucial to reparative healing following acute cardiomyocyte injury, chronic inflammation damages the heart, impairs function, and decreases cardiac output. Mitochondria, which comprise one third of cardiomyocyte volume, may prove a potential therapeutic target for heart failure. Known primarily for energy production, mitochondria are also involved in other processes including calcium homeostasis and the regulation of cellular apoptosis. Mitochondrial function is closely related to morphology, which alters through mitochondrial dynamics, thus ensuring that the energy needs of the cell are met. However, in heart failure, changes in substrate use lead to mitochondrial dysfunction and impaired myocyte function. This review discusses mitochondrial and cristae dynamics, including the role of the mitochondria contact site and cristae organizing system complex in mitochondrial ultrastructure changes. Additionally, this review covers the role of mitochondria-endoplasmic reticulum contact sites, mitochondrial communication via nanotunnels, and altered metabolite production during heart failure. We highlight these often-neglected factors and promising clinical mitochondrial targets for heart failure.

Low-intensity pulsed ultrasound improves myocardial ischaemia‒reperfusion injury via migrasome-mediated mitocytosis

During myocardial ischaemia‒reperfusion injury (MIRI), the accumulation of damaged mitochondria could pose serious threats to the heart. The migrasomes, newly discovered mitocytosis-mediating organelles, selectively remove damaged mitochondria to provide mitochondrial quality control. Here, we utilised low-intensity pulsed ultrasound (LIPUS) on MIRI mice model and demonstrated that LIPUS reduced the infarcted area and improved cardiac dysfunction. Additionally, we found that LIPUS alleviated MIRI-induced mitochondrial dysfunction. We provided new evidence that LIPUS mechanical stimulation facilitated damaged mitochondrial excretion via migrasome-dependent mitocytosis. Inhibition the formation of migrasomes abolished the protective effect of LIPUS on MIRI. Mechanistically, LIPUS induced the formation of migrasomes by evoking the RhoA/Myosin II/F-actin pathway. Meanwhile, F-actin activated YAP nuclear translocation to transcriptionally activate the mitochondrial motor protein KIF5B and Drp1, which are indispensable for LIPUS-induced mitocytosis. These results revealed that LIPUS activates mitocytosis, a migrasome-dependent mitochondrial quality control mechanism, to protect against MIRI, underlining LIPUS as a safe and potentially non-invasive treatment for MIRI.

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.

2-APQC, a small-molecule activator of Sirtuin-3 (SIRT3), alleviates myocardial hypertrophy and fibrosis by regulating mitochondrial homeostasis

Sirtuin 3 (SIRT3) is well known as a conserved nicotinamide adenine dinucleotide+ (NAD+)-dependent deacetylase located in the mitochondria that may regulate oxidative stress, catabolism and ATP production. Accumulating evidence has recently revealed that SIRT3 plays its critical roles in cardiac fibrosis, myocardial fibrosis and even heart failure (HF), through its deacetylation modifications. Accordingly, discovery of SIRT3 activators and elucidating their underlying mechanisms of HF should be urgently needed. Herein, we identified a new small-molecule activator of SIRT3 (named 2-APQC) by the structure-based drug designing strategy. 2-APQC was shown to alleviate isoproterenol (ISO)-induced cardiac hypertrophy and myocardial fibrosis in vitro and in vivo rat models. Importantly, in SIRT3 knockout mice, 2-APQC could not relieve HF, suggesting that 2-APQC is dependent on SIRT3 for its protective role. Mechanically, 2-APQC was found to inhibit the mammalian target of rapamycin (mTOR)-p70 ribosomal protein S6 kinase (p70S6K), c-jun N-terminal kinase (JNK) and transforming growth factor-β (TGF-β)/ small mother against decapentaplegic 3 (Smad3) pathways to improve ISO-induced cardiac hypertrophy and myocardial fibrosis. Based upon RNA-seq analyses, we demonstrated that SIRT3-pyrroline-5-carboxylate reductase 1 (PYCR1) axis was closely assoiated with HF. By activating PYCR1, 2-APQC was shown to enhance mitochondrial proline metabolism, inhibited reactive oxygen species (ROS)-p38 mitogen activated protein kinase (p38MAPK) pathway and thereby protecting against ISO-induced mitochondrialoxidative damage. Moreover, activation of SIRT3 by 2-APQC could facilitate AMP-activated protein kinase (AMPK)-Parkin axis to inhibit ISO-induced necrosis. Together, our results demonstrate that 2-APQC is a targeted SIRT3 activator that alleviates myocardial hypertrophy and fibrosis by regulating mitochondrial homeostasis, which may provide a new clue on exploiting a promising drug candidate for the future HF therapeutics.

Mechanical stress induced mitochondrial dysfunction in cardiovascular diseases: Novel mechanisms and therapeutic targets

Cardiovascular diseases (CVDs) are the leading cause of mortality worldwide. Others and our studies have shown that mechanical stresses (forces) including shear stress and cyclic stretch, occur in various pathological conditions, play significant roles in the development and progression of CVDs. Mitochondria regulate the physiological processes of cardiac and vascular cells mainly through adenosine triphosphate (ATP) production, calcium flux and redox control while promote cell death through electron transport complex (ETC) related cellular stress response. Mounting evidence reveal that mechanical stress-induced mitochondrial dysfunction plays a vital role in the pathogenesis of many CVDs including heart failure and atherosclerosis. This review summarized mitochondrial functions in cardiovascular system under physiological mechanical stress and mitochondrial dysfunction under pathological mechanical stress in CVDs (graphical abstract). The study of mitochondrial dysfunction under mechanical stress can further our understanding of the underlying mechanisms, identify potential therapeutic targets, and aid the development of novel treatments of CVDs.

Mitochondria-targeted BODIPY dyes for small molecule recognition, bio-imaging and photodynamic therapy

Mitochondria are essential for a diverse array of biological functions. There is increasing research focus on developing efficient tools for mitochondria-targeted detection and treatment. BODIPY dyes, known for their structural versatility and excellent spectroscopic properties, are being actively explored in this context. Numerous studies have focused on developing innovative BODIPYs that utilize optical signals for imaging mitochondria. This review presents a comprehensive overview of the progress made in this field, aiming to investigate mitochondria-related biological events. It covers key factors such as design strategies, spectroscopic properties, and cytotoxicity, as well as mechanism to facilitate their future application in organelle imaging and targeted therapy. This work is anticipated to provide valuable insights for guiding future development and facilitating further investigation into mitochondria-related biological sensing and phototherapy.

Correlation of ventricle epicardial fat volume and triglyceride-glucose index in patients with chronic heart failure

To explore the association of ventricle epicardial fat volume (EFV) calculated by cardiac magnetic resonance (CMR) and the insulin resistance indicator of triglyceride-glucose (TyG) index in patients with chronic HF (CHF), this retrospective cohort study included adult CHF patients with confirmed diagnosis of heart failure from January 2018 to December 2020. All patients underwent 3.0T CMR, and EFV were measured under short-axis cine. Spearman correlation, multivariate linear regression, and restricted cubic spline (RCS) regression were used to analyze their association. There were 516 patients with CHF, of whom 69.8% were male. Median EFV was 57.14mL and mean TyG index was 8.48. Spearman correlation analysis showed that TyG index was significantly correlated with the EFV in CHF patients (r = 0.247, P < 0.001). Further analysis showed that TyG index levels were significantly associated with EFV as both continuous variables (Unstandardized β = 6.556, P < 0.001) and across the increasing quartiles (β = 7.50, 95% CI [1.41, 13.59], P < 0.05). RCS demonstrated there were a positive trend and linear association between EFV and TyG index in CHF patients (P for nonliearity = 0.941). In patients with CHF, the TyG index was positively and linearly associated with the EFV, which supports the metabolic roles of epicardial adipose tissue regarding insulin resistance.

Triphenyl phosphate induces cardiotoxicity through myocardial fibrosis mediated by apoptosis and mitophagy of cardiomyocyte in mice

Triphenyl phosphate (TPHP) is an organophosphorus flame retardant, but its cardiac toxicity has not been adequately investigated. Therefore, in the current study, the effect of TPHP on the heart and the underlying mechanism involved was evaluated. C57BL/6 J mice were administered TPHP (0, 5, and 50 mg/kg/day) for 30 days. In addition, H9c2 cells were treated with three various concentrations (0, 50, and 150 μM) of TPHP, with and without the reactive oxygen species (ROS) scavenger N-acetyl-L-cysteine or the mitochondrial fusion promoter M1. TPHP caused cardiac fibrosis and increased the levels of CK-MB and LDH in the serum. TPHP increased the levels of ROS, malondialdehyde (MDA), and decreased the level of superoxide dismutase (SOD) and Glutathione peroxidase (GSH-Px). Furthermore, TPHP caused mitochondrial damage, and induced fusion and fission disorders that contributed to mitophagy in both the heart of C57BL/6 J mice and H9c2 cells. Transcriptome analysis showed that TPHP induced up- or down-regulated expression of various genes in myocardial tissue and revealed enriched apoptosis pathways. It was also found that TPHP could remarkably increase the expression levels of Bax, cleaved Caspase-9, cleaved Caspase-3, and decreased Bcl-2, thereby causing apoptosis in H9c2 cells. Taken together, the results suggested that TPHP promoted mitophagy through mitochondria fusion dysfunction resulting from oxidative stress, leading to fibrosis by inducing myocardial apoptosis.

Mitochondrial Dysfunction in Heart Failure: From Pathophysiological Mechanisms to Therapeutic Opportunities

Mitochondrial dysfunction, a feature of heart failure, leads to a progressive decline in bioenergetic reserve capacity, consisting in a shift of energy production from mitochondrial fatty acid oxidation to glycolytic pathways. This adaptive process of cardiomyocytes does not represent an effective strategy to increase the energy supply and to restore the energy homeostasis in heart failure, thus contributing to a vicious circle and to disease progression. The increased oxidative stress causes cardiomyocyte apoptosis, dysregulation of calcium homeostasis, damage of proteins and lipids, leakage of mitochondrial DNA, and inflammatory responses, finally stimulating different signaling pathways which lead to cardiac remodeling and failure. Furthermore, the parallel neurohormonal dysregulation with angiotensin II, endothelin-1, and sympatho-adrenergic overactivation, which occurs in heart failure, stimulates ventricular cardiomyocyte hypertrophy and aggravates the cellular damage. In this review, we will discuss the pathophysiological mechanisms related to mitochondrial dysfunction, which are mainly dependent on increased oxidative stress and perturbation of the dynamics of membrane potential and are associated with heart failure development and progression. We will also provide an overview of the potential implication of mitochondria as an attractive therapeutic target in the management and recovery process in heart failure.

Astragaloside IV alleviates LPS-induced cardiomyocyte hypertrophy and collagen expression associated with CCL2-mediated activation of NF-κB signaling pathway

Cardiac remodeling (CR), characterized by cardiac hypertrophy and fibrosis, leads to the development and progression of heart failure (HF). Nowadays, emerging evidence implicated that inflammation plays a vital role in the pathogenesis of CR and HF. Astragaloside IV (AS-IV), an effective component of Astragalus membranaceus, exerts cardio-protective and anti-inflammatory effects, but the underlying mechanism remains not fully elucidated. This present study aimed to investigate the effects of AS-IV on cardiac hypertrophy and fibrosis in cultured H9C2 cells stimulated with LPS, as well as explore its underlying mechanisms. As a result, we found AS-IV could reduce the cell surface size, ameliorate cardiac hypertrophy and fibrosis in LPS-induced H9C2 cells. To specify which molecules or signaling pathways play key roles in the process, RNA-seq analysis was performed. After analyzing the transcriptome data, CCL2 has captured our attention, of which expression was sharply increased in model group and reversed by AS-IV treatment. The results also indicated that AS-IV could ameliorate the inflammatory response by down-regulating NF-κB signaling pathway. Additionally, a classical inhibitor of CCL2 (bindarit) were used to further explore whether the anti-inflammatory effect of AS-IV was dependent on this chemokine. Our results indicated that AS-IV could exert a potent inhibitory effect on CCL2 expression and down-regulated NF-κB signaling pathway in a CCL2-dependent manner. These findings provided a scientific basis for promoting the treatment of HF with AS-IV.

Exploring the mechanism and phytochemicals in Psoraleae Fructus-induced hepatotoxicity based on RNA-seq, in vitro screening and molecular docking

Psoraleae Fructus (PF) is a widely-used herb with diverse pharmacological activities, while its related hepatic injuries have aroused public concerns. In this work, a systematic approach based on RNA sequencing (RNA-seq), high-content screening (HCS) and molecular docking was developed to investigate the potential mechanism and identify major phytochemicals contributed to PF-induced hepatotoxicity. Animal experiments proved oral administration of PF water extracts disturbed lipid metabolism and promoted hepatic injuries by suppressing fatty acid and cholesterol catabolism. RNA-seq combined with KEGG enrichment analysis identified mitochondrial oxidative phosphorylation (OXPHOS) as the potential key pathway. Further experiments validated PF caused mitochondrial structure damage, mtDNA depletion and inhibited expressions of genes engaged in OXPHOS. By detecting mitochondrial membrane potential and mitochondrial superoxide, HCS identified bavachin, isobavachalcone, bakuchiol and psoralidin as most potent mitotoxic compounds in PF. Moreover, molecular docking confirmed the potential binding patterns and strong binding affinity of the critical compounds with mitochondrial respiratory complex. This study unveiled the underlying mechanism and phytochemicals in PF-induced liver injuries from the view of mitochondrial dysfunction.

GLUD1 inhibits hepatocellular carcinoma progression via ROS-mediated p38/JNK MAPK pathway activation and mitochondrial apoptosis

Glutamate dehydrogenase 1 (GLUD1) is an important enzyme in glutamine metabolism. Previously, we found GLUD1 was down-regulated in tumor tissues of hepatocellular carcinoma (HCC) patients by proteomics study. To explore its role in the progression of HCC, the expressional level of GLUD1 was firstly examined and presented as that both the protein and mRNA levels were down-regulated in tumor tissues compared to the normal liver tissues. GLUD1 overexpression significantly inhibited HCC cells proliferation, migration, invasion and tumor growth both in vitro and in vivo, while GLUD1 knocking-down promoted HCC progression. Metabolomics study of GLUD1 overexpressing and control HCC cells showed that 129 differentially expressed metabolites were identified, which mainly included amino acids, bases, and phospholipids. Moreover, metabolites in mitochondrial oxidative phosphorylation system (OXPHOS) were differentially expressed in GLUD1 overexpressing cells. Mechanistic studies showed that GLUD1 overexpression enhanced mitochondrial respiration activity and reactive oxygen species (ROS) production. Excessive ROS lead to mitochondrial apoptosis that was characterized by increased expression levels of p53, Cytochrome C, Bax, Caspase 3 and decreased expression level of Bcl-2. Furthermore, we found that the p38/JNK MAPK pathway was activated in GLUD1 overexpressing cells. N-acetylcysteine (NAC) treatment eliminated cellular ROS and blocked p38/JNK MAPK pathway activation, as well as cell apoptosis induced by GLUD1 overexpression. Taken together, our findings suggest that GLUD1 inhibits HCC progression through regulating cellular metabolism and oxidative stress state, and provide that ROS generation and p38/JNK MAPK pathway activation as promising methods for HCC treatment.