Mitochondrial fatty acid oxidation is the major source of cardiac adenosine triphosphate production in heart failure with preserved ejection fraction

Cardiac energy substrate utilization in heart failure with preserved ejection fraction: reconciling conflicting evidence on fatty acid and glucose metabolism

Heart failure with preserved ejection fraction (HFpEF) is characterized by complex metabolic derangements, yet considerable controversy exists regarding the role, and specifically the direction, of fatty acid oxidation (FAO) in disease progression. Through a systematic review with narrative synthesis of 44 studies identified from MEDLINE, Embase, and Web of Science databases, we critically examine the seemingly contradictory evidence regarding cardiac FAO in HFpEF. Our systematic analysis of experimental approaches reveals that many apparent contradictions can be resolved by considering differences in methodological approaches, interpretation of indirect metabolic markers, and the dynamic nature of metabolic adaptation in disease progression. Direct measurements consistently demonstrate that FAO remains active or increased in HFpEF hearts, whereas glucose oxidation becomes impaired, challenging previous assumptions based on indirect metabolic assessments. Methodological differences, particularly between studies using isolated mitochondria versus intact hearts and indirect versus direct substrate utilization measurements, can explain many apparent contradictions in the literature. Clinical and experimental evidence supports that FAO is maintained or elevated in HFpEF, with primary defects occurring in glucose oxidation and mitochondrial quality control. These findings suggest that successful therapeutic strategies for HFpEF should prioritize restoring metabolic flexibility and optimizing substrate utilization patterns rather than simply modulating FAO pathways. Our synthesis of the literature provides a comprehensive framework for understanding cardiac energy metabolism in HFpEF and identifies critical areas for future investigation.NEW & NOTEWORTHY Direct measurements reveal fatty acid oxidation remains active or increased in HFpEF hearts, whereas glucose oxidation becomes impaired, challenging previous assumptions. Apparent contradictions in HFpEF metabolism literature arise from methodological differences-studies using isolated mitochondria versus intact hearts. Evidence demonstrates fatty acid oxidation is maintained in HFpEF, with defects primarily in glucose oxidation. Successful therapeutic strategies should prioritize restoring metabolic flexibility rather than simply modulating fatty acid oxidation pathways.

Alterations of myocardial ketone metabolism in heart failure with preserved ejection fraction (HFpEF)

INTRODUCTION

Cardiac energy metabolism is disrupted in heart failure with preserved ejection fraction (HFpEF), as characterized by a switch from glucose oxidation towards fatty acid oxidation. However, although oxidation of ketones is an important source of ATP it remains unclear how the heart oxidizes ketones in HFpEF. It is also unclear whether elevating ketone supply to the heart can improve cardiac energetics and/or provide functional benefit for the hearts in HFpEF.

AIMS

The present study investigated the effects of increasing ketone supply to the heart via ketone supplementation or SGLT2 inhibitor treatment in a mouse model of HFpEF.

METHODS

HFpEF was induced in 13-month-old C57BL/6N female mice with 60% high-fat diet and L-NAME (0.5 g/L/day in the drinking water) for 6 weeks. In parallel, two other groups of mice were maintained on the HFpEF protocol while also receiving either a ketone ester supplement (1-3 butanediol 1 g/kg/day) or SGLT2 inhibitor (empagliflozin 10 mg/kg/day) for 6 weeks. Control mice were fed with regular low-fat diet and regular drinking water. Hearts of the mice were excised and perfused in the isolated working mode aerobically with 5-mM glucose, 0.8-mM palmitate, 100-μU/mL insulin, with either low (0.6 mM) or high (1 mM) levels of β-hydroxybutyrate. Metabolic rates of the hearts were measured with radiolabelled [U-14C] glucose, [9,10-3H] palmitate and [3-14C] β-hydroxybutyrate.

RESULTS

In HFpEF mouse hearts, glucose oxidation was significantly decreased with a parallel increase in fatty acid oxidation. Increasing β-hydroxybutyrate levels from 0.6 to 1 mM in the perfusate resulted in a rise in ketone oxidation rates in control hearts (from 861 ± 63 to 1377 ± 94 nmol g dry wt-1 min-1), which was muted in HFpEF hearts (from 737 ± 68 to 897 ± 134 nmol g dry wt-1 min-1). Following ketone ester supplement or SGLT2 inhibitor treatment, HFpEF mice presented with restored ketone oxidation rates (from 674 ± 36 to 1181 ± 115 nmol g dry wt-1 min-1 with ketone ester supplement and from 797 ± 121 to 1240 ± 120 nmol g dry wt-1 min-1 with SGLT2i). Yet, this was not associated with improvement in cardiac function.

CONCLUSIONS

In HFpEF mice, the heart switches from glucose oxidation to fatty acid oxidation, with ketone oxidation being impaired. Increasing ketone supply to the heart via ketone ester supplementation or SGLT2 inhibitor treatment increases myocardial ketone oxidation rates but was not associated with functional improvements. Unlike HFrEF, ketone supplementation strategies may be less effective in HFpEF due to an impairment of myocardial ketone oxidation in HFpEF.

Decoding the Liver-Heart Axis in Cardiometabolic Diseases

The liver and heart are closely interconnected organs, and their bidirectional interaction plays a central role in cardiometabolic disease. In this review, we summarize current evidence linking liver dysfunction-particularly metabolic dysfunction-associated steatotic liver disease, alcohol-associated liver disease, and cirrhosis-with an increased risk of heart failure and other cardiovascular diseases. We discuss how these liver conditions contribute to cardiac remodeling, systemic inflammation, and hemodynamic stress and how cardiac dysfunction in turn impairs liver perfusion and promotes hepatic injury. Particular attention is given to the molecular mediators of liver-heart communication, including hepatokines and cardiokines, as well as the emerging role of advanced research methodologies, including omics integration, proximity labeling, and organ-on-chip platforms, that are redefining our understanding of interorgan cross talk. By integrating mechanistic insights with translational tools, this review aims to support the development of multiorgan therapeutic strategies for cardiometabolic disease.

Mitochondrial NNT Promotes Diastolic Dysfunction in Cardiometabolic HFpEF

BACKGROUND

Clinical management of heart failure with preserved ejection fraction (HFpEF) is hindered by a lack of disease-modifying therapies capable of altering its distinct pathophysiology. Despite the widespread implementation of a 2-hit model of cardiometabolic HFpEF to inform precision therapy, which utilizes ad libitum high-fat diet and 0.5% N(ω)-nitro-L-arginine methyl ester, we observe that C57BL6/J mice exhibit less cardiac diastolic dysfunction in response to high-fat diet and 0.5% N(ω)-nitro-L-arginine methyl ester.

METHODS

Genetic strain-specific single-nucleus transcriptomic analysis identified disease-relevant genes that enrich oxidative metabolic pathways within cardiomyocytes. Because C57BL/6J mice are known to harbor a loss-of-function mutation affecting the inner mitochondrial membrane protein Nnt (nicotinamide nucleotide transhydrogenase), we used an isogenic model of Nnt loss-of-function to determine whether intact NNT is necessary for the pathological cardiac manifestations of high-fat diet and 0.5% N(ω)-nitro-L-arginine methyl ester. Twelve-week-old mice cross-bred to isolate wild-type (Nnt+/+) or loss-of-function (Nnt-/-) Nnt in the C57BL/6N background were challenged with high-fat diet and 0.5% N(ω)-nitro-L-arginine methyl ester for 9 weeks (n=6-10).

RESULTS

Nnt+/+ mice exhibited impaired ventricular diastolic relaxation and pathological remodeling, as assessed via E/e' (42.8 versus 21.5, P=1.2×10-10), E/A (2.3 versus 1.4, P=4.1×10-2), diastolic stiffness (0.09 versus 0.04 mm Hg/μL, P=5.1×10-3), and myocardial fibrosis (P=2.3×10-2). Liquid chromatography and mass spectroscopy exposed a 40.0% reduction in NAD+ (P=8.4×10-3) and a 38.8% reduction in glutathione:GSSG (P=2.6×10-2) among Nnt+/+ mice after high-fat diet and 0.5% N(ω)-nitro-L-arginine methyl ester feeding. Using single-nucleus ligand-receptor analysis, we implicate Fgf1 (fibroblast growth factor 1) as a putative NNT-dependent mediator of cardiomyocyte-to-fibroblast signaling of myocardial fibrosis.

CONCLUSIONS

Together, these findings underscore the pivotal role of mitochondrial dysfunction in HFpEF pathogenesis, implicating both NNT and Fgf1 as novel therapeutic targets.

The Heart Has Intrinsic Ketogenic Capacity that Mediates NAD+ Therapy in HFpEF

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) has overtaken heart failure with reduced ejection fraction as the leading type of heart failure globally and is marked by high morbidity and mortality rates, yet with only a single approved pharmacotherapy: SGLT2i (sodium-glucose co-transporter 2 inhibitor). A prevailing theory for the mechanism underlying SGLT2i is nutrient deprivation signaling, of which ketogenesis is a hallmark. However, it is unclear whether the canonical ketogenic enzyme, HMGCS2 (3-hydroxy-3-methylglutaryl-coenzyme A synthase 2), plays any cardiac role in HFpEF pathogenesis or therapeutic response.

METHODS

We used human myocardium, human HFpEF and heart failure with reduced ejection fraction transcardiac blood sampling, an established murine model of HFpEF, ex vivo Langendorff perfusion, stable isotope tracing in isolated cardiomyocytes, targeted metabolomics, proteomics, lipidomics, and a novel cardiomyocyte-specific conditional HMGCS2-deficient model that we generated.

RESULTS

We demonstrate, for the first time, the intrinsic capacity of the human heart to produce ketones via HMGCS2. We found that increased acetylation of HMGCS2 led to a decrease in the enzyme's specific activity. However, this was overcome by an increase in the steady-state levels of protein. Oxidized form of nicotinamide adenine dinucleotide repletion restored HMGCS2 function via deacetylation, increased fatty acid oxidation, and rescued cardiac function in HFpEF. Critically, using a conditional, cardiomyocyte-specific HMGCS2 knockdown murine model, we revealed that the oxidized form of nicotinamide adenine dinucleotide is unable to rescue HFpEF in the absence of cardiomyocyte HMGCS2.

CONCLUSIONS

The canonical ketogenic enzyme, HMGCS2, mediates the therapeutic effects of the oxidized form of nicotinamide adenine dinucleotide repletion in HFpEF by restoring normal lipid metabolism and mitochondrial function.

Heart failure and obesity: Translational approaches and therapeutic perspectives. A scientific statement of the Heart Failure Association of the ESC

Obesity and heart failure (HF) represent two growing pandemics. In the general population, obesity affects one in eight adults and is linked with an increased risk for HF. Obesity is even more common in patients with HF, where it complicates the diagnosis of HF and is linked with worse symptoms and impaired exercise capacity. Over the past few years, new evidence on the mechanisms linking obesity with HF has been reported, particularly in relation to HF with preserved ejection fraction. Novel therapies inducing weight loss appear to have favourable effects on health status and cardiovascular risk. Against the backdrop of this rapidly evolving evidence landscape, HF clinicians are increasingly required to tailor their preventive, diagnostic, and therapeutic approaches to HF in the presence of obesity. This scientific statement by the Heart Failure Association of the European Society of Cardiology provides an up-to-date summary on obesity in HF, covering key areas such as epidemiology, translational aspects, diagnostic challenges, therapeutic approaches, and trial design.

Brevilin A, a novel BNIP3 inhibitor suppresses osteoclastogenesis and prevents ovariectomy-induced bone loss via impairing mitophagy and mitochondrial metabolism

BACKGROUND

The mitochondrial dysfunction and overactive osteoclasts is involved in the progress of osteoporosis. Brevilin A (BA), a sesquiterpene lactone, is a compound extracted and purified from Centipeda minima. It exhibits a range of pharmacological activities, such as anti-inflammatory and antioxidant effects. However, its specific impact on osteoporosis remains unclear. The present study is designed to explore BA as a novel osteoclast inhibitor for the treatment of osteoporosis as well as its molecular mechanisms of action via BNIP3-mediated mitophagy.

METHODS

The cytotoxicity of BA in vitro was evaluated using the CCK8 assay, while tartrate-resistant acid phosphatase (TRAcP) staining and bone resorption assays were conducted to examine its effects on osteoclastogenesis and osteoclast function. To elucidate the molecular mechanisms by which BA targets BNIP3 in osteoclasts, RNA-seq, molecular docking analysis, Surface plasmon resonance (SPR), qPCR, western blot, mitochondrial oxygen consumption rate (OCR), transmission electron microscopy (TEM), Single cell sequencing and immunofluorescence staining were employed. In addition, a specific BNIP3 agonist IOX5, was used to revalidate the inhibitory effect of BA on BNIP3. To investigate the effects and protective role of BA in modulating BNIP3 on bone loss in osteoporotic mice induced by ovariectomy (OVX), we employed in vivo micro-CT scanning and histological immunostaining techniques.

RESULTS

Our study demonstrated that BA inhibited RANKL-induced osteoclastogenesis in a concentration-dependent manner without any cell cytotoxicity. Further, BA abrogated MAPK-related proteins and intracellular and mitochondrial ROS level, subsequently inhibiting NFATc1 activity. RNA-seq analysis revealed that the molecular mechanism by which BA inhibited osteoclasts is closely related to mitophagy and mitochondrial function. Here, we found that BA suppressed oxygen consumption rate and mitochondrial oxidative phosphorylation during osteoclastogenesis. This compound abolished expression of ATG5, SIRT3, Beclin1 and LC3B. RANKL-induced mitophagy associated protein (PINK1 and Parkin) were also suppressed by BA. BA interacted with BNIP3 and IOX5 treatment further verified the targeted inhibition effect of BA on BNIP3. In addition, we found that BNIP3 deficient inhibited osteoclast differentiation related with mitophagy and mitochondrial function. In vivo experiments confirmed that BA significantly prevent OVX-induced bone loss associated with BNIP3-mediated mitophagy.

CONCLUSIONS

Our study reveals for the first time that BA acts as a novel inhibitor of BNIP3, which ameliorates osteoclast activity and OVX-induced osteoporosis via limiting mitophagy and mitochondrial energy production, suggesting that it could be a novel therapeutic strategy for osteoporosis.

Cardiac energy metabolism in diabetes: emerging therapeutic targets and clinical implications

Patients with diabetes are at an increased risk for developing diabetic cardiomyopathy and other cardiovascular complications. Alterations in cardiac energy metabolism in patients with diabetes, including an increase in mitochondrial fatty acid oxidation and a decrease in glucose oxidation, are important contributing factors to this increase in cardiovascular disease. A switch from glucose oxidation to fatty acid oxidation not only decreases cardiac efficiency due to increased oxygen consumption but it can also increase reactive oxygen species production, increase lipotoxicity, and redirect glucose into other metabolic pathways that, combined, can lead to heart dysfunction. Currently, there is a lack of therapeutics available to treat diabetes-induced heart failure that specifically target cardiac energy metabolism. However, it is becoming apparent that part of the benefit of existing agents such as GLP-1 receptor agonists and sodium-glucose cotransporter 2 inhibitors may be related to their effects on cardiac energy metabolism. In addition, direct approaches aimed at inhibiting cardiac fatty acid oxidation or increasing glucose oxidation hold future promise as potential therapeutic approaches to treat diabetes-induced cardiovascular disease.

Cardioprotective effect of 19,20-epoxydocosapentaenoic acid (19,20-EDP) in ischaemic injury involves direct activation of mitochondrial sirtuin 3

AIMS

Although current clinical therapies following myocardial infarction (MI) have improved patient outcomes, morbidity, and mortality rates, secondary to ischaemic and ischaemia reperfusion (IR) injury remains high. Maintaining mitochondrial quality is essential to limit myocardial damage following cardiac ischaemia and IR injury. The mitochondrial deacetylase sirtuin 3 (SIRT3) plays a pivotal role in regulating mitochondrial function and cardiac energy metabolism. In the current study, we hypothesize that 19,20-epoxydocosapentaenoic acid (19,20-EDP) attenuates cardiac IR injury via stimulating mitochondrial SIRT3.

METHODS AND RESULTS

Ex vivo models of isolated heart perfusions were performed in C57BL/6 mice to assess the effect of 19,20-EDP on cardiac function and energy metabolism following IR injury. In vivo permanent occlusion of the left anterior descending coronary artery was performed to induce MI; mice were administered 19,20-EDP with or without the SIRT3 selective inhibitor 3-TYP. Mitochondrial SIRT3 targets and respiration were assessed in human left ventricular tissues obtained from individuals with ischaemic heart disease (IHD) and compared to non-failing controls (NFCs). Binding affinity of 19,20-EDP to human SIRT3 was assessed using molecular modelling and fluorescence thermal shift assay. Results demonstrated that hearts treated with 19,20-EDP had improved post-ischaemic cardiac function, better glucose oxidation rates, and enhanced cardiac efficiency. The cardioprotective effects were associated with enhanced mitochondrial SIRT3 activity. Interestingly, treatment with 19,20-EDP markedly improved mitochondrial respiration and SIRT3 activity in human left ventricle (LV) fibres with IHD compared to NFC. Moreover, 19,20-EDP was found to bind to the human SIRT3 protein enhancing the NAD+-complex stabilization leading to improved SIRT3 activity. Importantly, the beneficial effects of 19,20-EDP were abolished by SIRT3 inhibition or using the S149A mutant SIRT3.

CONCLUSION

These data demonstrate that 19,20-EDP-mediated cardioprotective mechanisms against ischaemia and IR injury involve mitochondrial SIRT3, resulting in improved cardiac efficiency.

Methylations in dilated cardiomyopathy and heart failure

Dilated cardiomyopathy (DCM) is characterized by impaired expansion or contraction of the left or both ventricles in the absence of abnormal load conditions (such as primary valve disease) or severe coronary artery disease that can lead to ventricular remodeling. Genetic mutations, infections, inflammation, autoimmune diseases, exposure to toxins, and endocrine or neuromuscular factors have all been implicated in the causation of DCM. Cardiomyopathy, particularly DCM, often has genetic underpinnings, with established or suspected genetic origins. Up to 40% of DCM cases involve probable or confirmed genetic variations. The significance of RNA modification in the pathogenesis of hypertension, cardiac hypertrophy, and atherosclerosis is well-established. Of late, RNA methylation has garnered attention for its involvement in DCM. This review examines the biological mechanisms and effects of RNA methylation in DCM and heart failure.

Metabolic Adaptations and Therapies in Cardiac Hypoxia: Mechanisms and Clinical Implications/ Potential Strategies

Cardiac hypoxia triggers a cascade of responses and functional changes in myocardial and non-myocardial cells, profoundly affecting cellular metabolism, oxygen-sensing mechanisms, and immune responses. Myocardial cells, being the primary cell type in cardiac tissue, undergo significant alterations in energy metabolism, including glycolysis, fatty acid metabolism, ketone body utilization, and branched-chain amino acid metabolism, to maintain cardiac function under hypoxic conditions. Non-myocardial cells, such as fibroblasts, endothelial cells, and immune cells, although fewer in number, play crucial roles in regulating cardiac homeostasis, maintaining structural integrity, and responding to injury. This review discusses the metabolic reprogramming of immune cells, particularly macrophages, during ischemia-reperfusion injury and explores various therapeutic strategies that modulate these metabolic pathways to protect the heart during hypoxia. Understanding these interactions provides valuable insights and potential therapeutic targets for heart disease treatment.

Visceral obesity and HFpEF: targets and therapeutic opportunities

The effectiveness of weight-loss drugs in heart failure (HF) with preserved ejection fraction (HFpEF) highlights the link between obesity (adipose tissue) and HF (the heart). Recent guidelines incorporating the waist:height ratio for diagnosing and treating obesity reflect the growing recognition of the significance of visceral adiposity. However, its unique impact on HFpEF and their complex relationship remain underexplored. With limited treatment options for obesity-related HFpEF, novel disease-modifying treatments are urgently needed. Here, we clarify the relationship between visceral obesity and HFpEF, introducing the concept of the visceral adipose tissue-heart axis to explore its mechanisms and therapeutic potential. We also discuss promising strategies targeting visceral obesity in HFpEF and propose directions for future research.

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.

Insights Into the Role of Obesity in Heart Failure With Preserved Ejection Fraction Pathophysiology and Management

Heart failure (HF) is a significant global health issue, categorized by left ventricular ejection fraction, being either reduced (HFrEF < 0.40) or preserved (HFpEF > 0.50), or in the middle of this range. Although the overall incidence of HF remains stable, HFpEF cases are increasing, representing about 50% of all HF cases. Outcomes for HFpEF are similar to those for HFrEF, leading to substantial health-care resource use. Despite extensive research over the past 2 decades, the prognosis and mortality rates for HFpEF remain high. A key feature of HFpEF is exercise intolerance, characterized by severe exertional dyspnea and fatigue, which significantly impacts quality of life. The underlying mechanisms of exercise intolerance are not fully understood due to the complex pathophysiology and multisystem involvement. Obesity is a common comorbidity in HFpEF, especially in North America, leading to worsening symptoms, hemodynamics, and mortality rates. Increased adiposity leads to inflammation, hypertension, dyslipidemia, and insulin resistance, and impairing cardiac, vascular, pulmonary, and skeletal muscle function. Therefore, managing obesity is crucial in treating HFpEF. In this review we explore the pathophysiologic mechanisms of HFpEF, emphasizing obesity's role, and we discuss current management strategies while identifying areas needing further research.

Myocardial Proteome in Human Heart Failure With Preserved Ejection Fraction

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) constitutes more than half of all HF but has few effective therapies. Recent human myocardial transcriptomics and metabolomics have identified major differences between HFpEF and controls. How this translates at the protein level is unknown.

METHODS AND RESULTS

Myocardial tissue from patients with HFpEF and nonfailing donor controls was analyzed by data-dependent acquisition (n=10 HFpEF, n=10 controls) and data-independent acquisition (n=44 HFpEF, n=5 controls) mass spectrometry-based proteomics. Differential protein expression analysis, pathway overrepresentation, weighted coexpression network analysis, and machine learning were integrated with clinical characteristics and previously reported transcriptomics. Principal component analysis (data-dependent acquisition-mass spectrometry) found HFpEF separated into 2 subgroups: one similar to controls and the other disparate. Downregulated proteins in HFpEF versus controls were enriched in mitochondrial transport/organization, translation, and metabolism including oxidative phosphorylation. Proteins upregulated in HFpEF were related to immune activation, reactive oxygen species, and inflammatory response. Ingenuity pathway analysis predicted downregulation of protein translation, mitochondrial function, and glucose and fat metabolism in HFpEF. Expression of oxidative phosphorylation and metabolism genes (higher) versus proteins (lower) was discordant in HFpEF versus controls. Data-independent acquisition-mass spectrometry proteomics also yielded 2 HFpEF subgroups; the one most different from controls had a higher proportion of patients with severe obesity and exhibited lower proteins related to fuel metabolism, oxidative phosphorylation, and protein translation. Three modules of correlated proteins in HFpEF that correlated with left ventricular hypertrophy and right ventricular load related to (1) proteasome; (2) fuel metabolism; and (3) protein translation, oxidative phosphorylation, and sarcomere organization.

CONCLUSIONS

Integrative proteomics, transcriptomics, and pathway analysis supports a defect in both metabolism and translation in HFpEF. Patients with HFpEF with more distinct proteomic signatures from control more often had severe obesity, supporting therapeutic efforts targeting metabolism and translation, particularly in this subgroup.

Molecular Mechanisms Underlying Heart Failure and Their Therapeutic Potential

Heart failure (HF) is a prominent fatal cardiovascular disorder afflicting 3.4% of the adult population despite the advancement of treatment options. Therefore, a better understanding of the pathogenesis of HF is essential for exploring novel therapeutic strategies. Hypertrophy and fibrosis are significant characteristics of pathological cardiac remodeling, contributing to HF. The mechanisms involved in the development of cardiac remodeling and consequent HF are multifactorial, and in this review, the key underlying mechanisms are discussed. These have been divided into the following categories thusly: (i) mitochondrial dysfunction, including defective dynamics, energy production, and oxidative stress; (ii) cardiac lipotoxicity; (iii) maladaptive endoplasmic reticulum (ER) stress; (iv) impaired autophagy; (v) cardiac inflammatory responses; (vi) programmed cell death, including apoptosis, pyroptosis, and ferroptosis; (vii) endothelial dysfunction; and (viii) defective cardiac contractility. Preclinical data suggest that there is merit in targeting the identified pathways; however, their clinical implications and outcomes regarding treating HF need further investigation in the future. Herein, we introduce the molecular mechanisms pivotal in the onset and progression of HF, as well as compounds targeting the related mechanisms and their therapeutic potential in preventing or rescuing HF. This, therefore, offers an avenue for the design and discovery of novel therapies for the treatment of HF.

Mitochondrial complex-1 as a therapeutic target for cardiac diseases

Mitochondrial dysfunction is critical for the development and progression of cardiovascular diseases (CVDs). Complex-1 (CI) is an essential component of the mitochondrial electron transport chain that participates in oxidative phosphorylation and energy production. CI is the largest multisubunit complex (~ 1 Mda) and comprises 45 protein subunits encoded by seven mt-DNA genes and 38 nuclear genes. These subunits function as the enzyme nicotinamide adenine dinucleotide  hydrogen (NADH): ubiquinone oxidoreductase. CI dysregulation has been implicated in various CVDs, including heart failure, ischemic heart disease, pressure overload, hypertrophy, and cardiomyopathy. Several studies demonstrated that impaired CI function contributes to increased oxidative stress, altered calcium homeostasis, and mitochondrial DNA damage in cardiac cells, leading to cardiomyocyte dysfunction and apoptosis. CI dysfunction has been associated with endothelial dysfunction, inflammation, and vascular remodeling, critical processes in developing atherosclerosis and hypertension. Although CI is crucial in physiological and pathological conditions, no potential therapeutics targeting CI are available to treat CVDs. We believe that a lack of understanding of CI's precise mechanisms and contributions to CVDs limits the development of therapeutic strategies. In this review, we comprehensively analyze the role of CI in cardiovascular health and disease to shed light on its potential therapeutic target role in CVDs.

The Impact of Obesity on Cardiac Energy Metabolism and Efficiency in Heart Failure With Preserved Ejection Fraction

The incidence and prevalence of heart failure with preserved ejection fraction (HFpEF) continues to rise, and now comprises more than half of all heart failure cases. There are many risk factors for HFpEF, including older age, hypertension, diabetes, dyslipidemia, sedentary behaviour, and obesity. The rising prevalence of obesity in society is a particularly important contributor to HFpEF development and severity. Obesity can adversely affect the heart, including inducing marked alterations in cardiac energy metabolism. This includes obesity-induced impairments in mitochondrial function, and an increase in fatty acid uptake and mitochondrial fatty acid β-oxidation. This increase in myocardial fatty acid metabolism is accompanied by an impaired myocardial insulin signaling and a marked decrease in glucose oxidation. This switch from glucose to fatty acid metabolism decreases cardiac efficiency and can contribute to severity of HFpEF. Increased myocardial fatty acid uptake in obesity is also associated with the accumulation of fatty acids, resulting in cardiac lipotoxicity. Obesity also results in dramatic changes in the release of adipokines, which can negatively impact cardiac function and energy metabolism. Obesity-induced increases in epicardial fat can also increase cardiac insulin resistance and negatively affect cardiac energy metabolism and HFpEF. However, optimizing cardiac energy metabolism in obese subjects may be one approach to preventing and treating HFpEF. This review discusses what is presently known about the effects of obesity on cardiac energy metabolism and insulin signaling in HFpEF. The clinical implications of obesity and energy metabolism on HFpEF are also discussed.

Caloric restriction and its mimetics in heart failure with preserved ejection fraction: mechanisms and therapeutic potential

The global increase in human life expectancy, coupled with an unprecedented rise in the prevalence of obesity, has led to a growing clinical and socioeconomic burden of heart failure with preserved ejection fraction (HFpEF). Mechanistically, the molecular and cellular hallmarks of aging are omnipresent in HFpEF and are further exacerbated by obesity and associated metabolic diseases. Conversely, weight loss strategies, particularly caloric restriction, have shown promise in improving health status in patients with HFpEF and are considered the gold standard for promoting longevity and healthspan (disease-free lifetime) in model organisms. In this review, we implicate fundamental mechanisms of aging in driving HFpEF and elucidate how caloric restriction mitigates the disease progression. Furthermore, we discuss the potential for pharmacologically mimicking the beneficial effects of caloric restriction in HFpEF using clinically approved and emerging caloric restriction mimetics. We surmise that these compounds could offer novel therapeutic avenues for HFpEF and alleviate the challenges associated with the implementation of caloric restriction and other lifestyle modifications to reduce the burden of HFpEF at a population level.

Protective role of 3-mercaptopyruvate sulfurtransferase (MPST) in the development of metabolic syndrome and vascular inflammation

Metabolic syndrome (MetS) is a cluster of metabolic abnormalities that occur concurrently and increase the risk of cardiovascular disease. 3-mercaptopyruvate sulfurtransferase (MPST) is a cysteine-catabolizing enzyme that yields pyruvate and hydrogen sulfide (H2S) and plays a central role in the regulation of energy homeostasis. Herein, we seek to investigate the role of MPST/H2S in MetS and its cardiovascular consequences using a mouse model of the disease. Mice were fed a high-fat diet (HFD) for 15 weeks to induce obesity and hyperglycemia and administrated a nitric oxide synthase inhibitor, during the last 5 weeks to induce hypertension and MetS. This model caused a mild left ventricular (LV) diastolic dysfunction and vascular endothelial dysfunction. Free H2S and sulfane-sulfur levels were decreased in the aorta, but unaltered in the heart. Also, downregulation of MPST and thiosulfate sulfuretransferase (TST) were observed in the aorta. Global deletion of Mpst (Mpst-/-) resulted in increased body weight and greater glucose intolerance in mice with MetS, without affecting their blood pressure, and caused an upregulation of genes involved in immune responses in the vasculature suggestive of T-cell infiltration and activation. Pharmacological restoration of H2S levels ameliorated the comorbidities of MetS; GYY4137 administration reduced body weight and blood pressure, attenuated cardiac fibrosis and improved glucose handling and endothelium-dependent relaxation. In conclusion, this study found that reduced MPST/H2S exacerbates the pathological changes associated with MetS and contributes to vascular inflammation. H2S supplementation emerges as a potential therapeutic approach to treat the abnormalities associated with MetS.

Intercellular Mitochondrial transfer: Therapeutic implications for energy metabolism in heart failure

Heart failure (HF) remains one of the leading causes of high morbidity and mortality globally. Impaired cardiac energy metabolism plays a critical role in the pathological progression of HF. Various forms of HF exhibit marked differences in energy metabolism, particularly in mitochondrial function and substrate utilization. Recent studies have increasingly highlighted that improving energy metabolism in HF patients as a crucial treatment strategy. Mitochondrial transfer is emerging as a promising and precisely regulated therapeutic strategy for treating metabolic disorders. This paper specifically reviews the characteristics of mitochondrial energy metabolism across different types of HF and explores the modes and mechanisms of mitochondrial transfer between different cell types in the heart, such as cardiomyocytes, fibroblasts, and immune cells. We focused on the therapeutic potential of intercellular mitochondrial transfer in improving energy metabolism disorders in HF. We also discuss the role of signal transduction in mitochondrial transfer, highlighting that mitochondria not only function as energy factories but also play crucial roles in intercellular communication, metabolic regulation, and tissue repair. This study provides new insights into improving energy metabolism in heart failure patients and proposes promising new therapeutic strategies.

CEACAM6 facilitates gastric cancer progression through upregulating SLC27A2

Gastric cancer (GC) is one of the most lethal cancers. However, the underlying mechanisms are not yet fully understood. Here, we investigated the role of carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) in tumor initiation and progression in GC and proposed therapeutic strategies for CEACAM6-positive patients. In this article, we found that CEACAM6 overexpression promoted GC initiation and progression by overactivating FAO. CEACAM6 promotes SLC27A2 expression, contributing to enhanced fatty acid incorporation. CEACAM6 interacts with both SLC27A2 and USP29, facilitating the deubiquitination of USP29 on SLC27A2. Pharmacological inhibition of SLC27A2 attenuates the tumor-initiating ability of GC. Taken together, CEACAM6 overexpression facilitates GC progression by upregulating fatty acid uptake through SLC27A2, thereby contributing to FAO. Genetic ablation of SLC27A2 is a promising therapeutic strategy for patients with CEACAM6-positive GC.

Advances in myocardial energy metabolism: metabolic remodelling in heart failure and beyond

The very high energy demand of the heart is primarily met by adenosine triphosphate (ATP) production from mitochondrial oxidative phosphorylation, with glycolysis providing a smaller amount of ATP production. This ATP production is markedly altered in heart failure, primarily due to a decrease in mitochondrial oxidative metabolism. Although an increase in glycolytic ATP production partly compensates for the decrease in mitochondrial ATP production, the failing heart faces an energy deficit that contributes to the severity of contractile dysfunction. The relative contribution of the different fuels for mitochondrial ATP production dramatically changes in the failing heart, which depends to a large extent on the type of heart failure. A common metabolic defect in all forms of heart failure [including heart failure with reduced ejection fraction (HFrEF), heart failure with preserved EF (HFpEF), and diabetic cardiomyopathies] is a decrease in mitochondrial oxidation of pyruvate originating from glucose (i.e. glucose oxidation). This decrease in glucose oxidation occurs regardless of whether glycolysis is increased, resulting in an uncoupling of glycolysis from glucose oxidation that can decrease cardiac efficiency. The mitochondrial oxidation of fatty acids by the heart increases or decreases, depending on the type of heart failure. For instance, in HFpEF and diabetic cardiomyopathies myocardial fatty acid oxidation increases, while in HFrEF myocardial fatty acid oxidation either decreases or remains unchanged. The oxidation of ketones (which provides the failing heart with an important energy source) also differs depending on the type of heart failure, being increased in HFrEF, and decreased in HFpEF and diabetic cardiomyopathies. The alterations in mitochondrial oxidative metabolism and glycolysis in the failing heart are due to transcriptional changes in key enzymes involved in the metabolic pathways, as well as alterations in redox state, metabolic signalling and post-translational epigenetic changes in energy metabolic enzymes. Of importance, targeting the mitochondrial energy metabolic pathways has emerged as a novel therapeutic approach to improving cardiac function and cardiac efficiency in the failing heart.

Characterization of a novel ovine model of hypertensive heart failure with preserved ejection fraction

The lack of animal models that accurately represent heart failure with preserved ejection fraction (HFpEF) has been a major barrier to the mechanistic understanding and development of effective therapies for this prevalent and debilitating syndrome characterized by multisystem impairments. Herein, we describe the development and characterization of a novel large animal model of HFpEF in older, female sheep with chronic 2-kidney, 1-clip hypertension. At 6-wk post unilateral renal artery clipping, hypertensive HFpEF sheep had higher mean arterial pressure compared with similarly aged ewes without unilateral renal artery clipping (mean arterial pressure = 112.7 ± 15.9 vs. 76.0 ± 10.1 mmHg, P < 0.0001). The hypertensive HFpEF sheep were characterized by 1) echocardiographic evidence of diastolic dysfunction (lateral e' = 0.11 ± 0.02 vs. 0.14 ± 0.04 m/s, P = 0.011; lateral E/e' = 4.25 ± 0.77 vs. 3.63 ± 0.54, P = 0.028) and concentric left ventricular hypertrophy without overt systolic impairment, 2) elevated directly measured left ventricular end-diastolic pressure (13 ± 5 vs. 0.5 ± 1 mmHg, P = 2.1 × 10-6), and 3) normal directly measured cardiac output. Crucially, these hypertensive HFpEF sheep had impaired exercise capacity as demonstrated by their 1) attenuated cardiac output (P = 0.001), 2) augmented pulmonary capillary wedge pressure (P = 0.026), and 3) attenuated hindlimb blood flow (P = 3.4 × 10-4) responses, during graded treadmill exercise testing. In addition, exercise renal blood flow responses were also altered. Collectively, our data indicates that this novel ovine model of HFpEF may be a useful translational research tool because it exhibits similar and clinically relevant impairments as that of patients with HFpEF.NEW & NOTEWORTHY We show that older, female sheep with chronic 2-kidney, 1-clip hypertension have similar cardiac and noncardiac exercise hemodynamic abnormalities as patients with HFpEF. This clinically relevant, translatable, and novel large animal model of HFpEF may be useful for elucidating mechanisms and developing treatments for this increasingly common syndrome with few clinically impactful therapies.

Cardiometabolic effects of sacubitril/valsartan in a rat model of heart failure with preserved ejection fraction

The promising results obtained in the PARADIGM-HF trial prompted the approval of sacubitril/valsartan (SAC/VAL) as a first-in-class treatment for heart failure with reduced ejection fraction (HFrEF) patients. The effect of SAC/VAL treatment was also studied in patients with heart failure with preserved ejection fraction (HFpEF) and, although improvements in New York Heart Association (NYHA) class, HF hospitalizations, and cardiovascular deaths were observed, these results were not so promising. However, the demand for HFpEF therapies led to the approval of SAC/VAL as an alternative treatment, although further studies are needed. We aimed to elucidate the effects of a 9-week SAC/VAL treatment in cardiac function and metabolism using a preclinical model of HFpEF, the Zucker Fatty and Spontaneously Hypertensive (ZSF1) rats. We found that SAC/VAL significantly improved diastolic function parameters and modulated respiratory quotient during exercise. Ex-vivo studies showed that SAC/VAL treatment significantly decreased heart, liver, spleen, and visceral fat weights; cardiac hypertrophy and percentage of fibrosis; lipid infiltration in liver and circulating levels of cholesterol and sodium. Moreover, SAC/VAL reduced glycerophospholipids, cholesterol, and cholesteryl esters while increasing triglyceride levels in cardiac tissue. In conclusion, SAC/VAL treatment improved diastolic and hepatic function, respiratory metabolism, reduced hypercholesterolemia and cardiac fibrosis and hypertrophy, and was able to modulate cardiac metabolic profile. Our findings might provide further insight into the therapeutic benefits of SAC/VAL treatment in obese patients with HFpEF.

Oleoylethanolamide mitigates cardiometabolic disruption secondary to obesity induced by high-fat diet in mice

Chronic lipid overnutrition has been demonstrated to promote cardiac dysfunction resulting from metabolic derangement, inflammation, and fibrosis. Oleoylethanolamide (OEA), an endogenous peroxisome proliferator activating receptor (PPAR)-α agonist, has been extensively studied for its metabolic properties. The aim of this study was to determine if OEA has beneficial effects on high-fat diet (HFD)-induced cardiac disruption in obese mice, focusing on the underlying pathological mechanisms. OEA treatment restores the metabolic pattern, improving serum glycaemic and lipid profile. OEA also reduces heart weight and serum creatine kinase-myocardial band (CK-MB), a marker of cardiac damage. Accordingly, OEA modulates cardiac metabolism, increasing insulin signaling and reducing lipid accumulation. OEA increases AMPK and AKT phosphorylation, converging in the rise of AS160 activation and glucose transporter (GLUT)4 protein level. Moreover, OEA reduces the transcription of the cardiac fatty acid transporter CD36 and fatty acid synthase and increases PPAR-α mRNA levels. Adiponectin and meteorite-like protein transcription levels were significantly reduced by OEA in HFD mice, as well as those of inflammatory cytokines and pro-fibrotic markers. An increased autophagic process was also shown, contributing to OEA's cardioprotective effects. Metabolomic analyses of cardiac tissue revealed the modulation of different lipids, including triglycerides, glycerophospholipids and sphingomyelins by OEA treatment. In vitro experiments on HL-1 cardiomyocytes showed OEA's capability in reducing inflammation and fibrosis following palmitate challenge, demonstrating a direct activity of OEA on cardiac cells, mainly mediated by PPAR-α activation. Our results indicate OEA as a potential therapeutic to restrain cardiac damage associated with metabolic disorders.

The aging heart in focus: The advanced understanding of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) accounts for 50 % of heart failure (HF) cases, making it the most common type of HF, and its prevalence continues to increase in the aging society. HFpEF is a systemic syndrome resulting from many risk factors, such as aging, metabolic syndrome, and hypertension, and its clinical features are highly heterogeneous in different populations. HFpEF syndrome involves the dysfunction of multiple organs, including the heart, lung, muscle, and vascular system. The heart shows dysfunction of various cells, including cardiomyocytes, endothelial cells, fibroblasts, adipocytes, and immune cells. The complex etiology and pathobiology limit experimental research on HFpEF in animal models, delaying a comprehensive understanding of the mechanisms and making treatment difficult. Recently, many scientists and cardiologists have attempted to improve the clinical outcomes of HFpEF. Recent advances in clinically related animal models and systemic pathology studies have improved our understanding of HFpEF, and clinical trials involving sodium-glucose cotransporter 2 inhibitors have significantly enhanced our confidence in treating HFpEF. This review provides an updated comprehensive discussion of the etiology and pathobiology, molecular and cellular mechanisms, preclinical animal models, and therapeutic trials in animals and patients to enhance our understanding of HFpEF and improve clinical outcomes.

Oxidative Stress and Inflammation in Myocardial Ischemia-Reperfusion Injury: Protective Effects of Plant-Derived Natural Active Compounds

Acute myocardial infarction (AMI) remains a leading cause of death among patients with cardiovascular diseases. Percutaneous coronary intervention (PCI) has been the preferred clinical treatment for AMI due to its safety and efficiency. However, research indicates that the rapid restoration of myocardial oxygen supply following PCI can lead to secondary myocardial injury, termed myocardial ischemia-reperfusion injury (MIRI), posing a grave threat to patient survival. Despite ongoing efforts, the mechanisms underlying MIRI are not yet fully elucidated. Among them, oxidative stress and inflammation stand out as critical pathophysiological mechanisms, playing significant roles in MIRI. Natural compounds have shown strong clinical therapeutic potential due to their high efficacy, availability, and low side effects. Many current studies indicate that natural compounds can mitigate MIRI by reducing oxidative stress and inflammatory responses. Therefore, this paper reviews the mechanisms of oxidative stress and inflammation during MIRI and the role of natural compounds in intervening in these processes, aiming to provide a basis and reference for future research and development of drugs for treating MIRI.

Mitochondrial Reactive Oxygen Species Dysregulation in Heart Failure with Preserved Ejection Fraction: A Fraction of the Whole

Heart failure with preserved ejection fraction (HFpEF) is a multifarious syndrome, accounting for over half of heart failure (HF) patients receiving clinical treatment. The prevalence of HFpEF is rapidly increasing in the coming decades as the global population ages. It is becoming clearer that HFpEF has a lot of different causes, which makes it challenging to find effective treatments. Currently, there are no proven treatments for people with deteriorating HF or HFpEF. Although the pathophysiologic foundations of HFpEF are complex, excessive reactive oxygen species (ROS) generation and increased oxidative stress caused by mitochondrial dysfunction seem to play a critical role in the pathogenesis of HFpEF. Emerging evidence from animal models and human myocardial tissues from failed hearts shows that mitochondrial aberrations cause a marked increase in mitochondrial ROS (mtROS) production and oxidative stress. Furthermore, studies have reported that common HF medications like beta blockers, angiotensin receptor blockers, angiotensin-converting enzyme inhibitors, and mineralocorticoid receptor antagonists indirectly reduce the production of mtROS. Despite the harmful effects of ROS on cardiac remodeling, maintaining mitochondrial homeostasis and cardiac functions requires small amounts of ROS. In this review, we will provide an overview and discussion of the recent findings on mtROS production, its threshold for imbalance, and the subsequent dysfunction that leads to related cardiac and systemic phenotypes in the context of HFpEF. We will also focus on newly discovered cellular and molecular mechanisms underlying ROS dysregulation, current therapeutic options, and future perspectives for treating HFpEF by targeting mtROS and the associated signal molecules.

Integrated systems biology identifies disruptions in mitochondrial function and metabolism as key contributors to heart failure with preserved ejection fraction (HFpEF)

Background

Heart failure with preserved ejection fraction (HFpEF) accounts for ~50% of HF cases, with no effective treatments. The ZSF1-obese rat model recapitulates numerous clinical features of HFpEF including hypertension, obesity, metabolic syndrome, exercise intolerance, and LV diastolic dysfunction. Here, we utilized a systems-biology approach to define the early metabolic and transcriptional signatures to gain mechanistic insight into the pathways contributing to HFpEF development.

Methods

Male ZSF1-obese, ZSF1-lean hypertensive controls, and WKY (wild-type) controls were compared at 14w of age for extensive physiological phenotyping and LV tissue harvesting for unbiased metabolomics, RNA-sequencing, and assessment of mitochondrial morphology and function. Utilizing ZSF1-lean and WKY controls enabled a distinction between hypertension-driven molecular changes contributing to HFpEF pathology, versus hypertension + metabolic syndrome.

Results

ZSF1-obese rats displayed numerous clinical features of HFpEF. Comparison of ZSF1-lean vs WKY (i.e., hypertension-exclusive effects) revealed metabolic remodeling suggestive of increased aerobic glycolysis, decreased β-oxidation, and dysregulated purine and pyrimidine metabolism with few transcriptional changes. ZSF1-obese rats displayed worsened metabolic remodeling and robust transcriptional remodeling highlighted by the upregulation of inflammatory genes and downregulation of the mitochondrial structure/function and cellular metabolic processes. Integrated network analysis of metabolomic and RNAseq datasets revealed downregulation of nearly all catabolic pathways contributing to energy production, manifesting in a marked decrease in the energetic state (i.e., reduced ATP/ADP, PCr/ATP). Cardiomyocyte ultrastructure analysis revealed decreased mitochondrial area, size, and cristae density, as well as increased lipid droplet content in HFpEF hearts. Mitochondrial function was also impaired as demonstrated by decreased substrate-mediated respiration and dysregulated calcium handling.

Conclusions

Collectively, the integrated omics approach applied here provides a framework to uncover novel genes, metabolites, and pathways underlying HFpEF, with an emphasis on mitochondrial energy metabolism as a potential target for intervention.

Hypertension and obesity independently drive hypertrophy and alter mitochondrial metabolism in a mouse model of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) has recently emerged as an insidiously and increasingly prevalent heart failure phenotype. HFpEF often occurs in the context of hypertension and obesity and presents with diastolic dysfunction, ventricular hypertrophy, and myocardial fibrosis. Despite growing study of HFpEF, the causal links between early metabolic changes, bioenergetic perturbations, and cardiac structural remodeling remain unclear. This study sought to elucidate the contribution of the respective pathophysiological drivers of the HFpEF symptom suite using a recently developed two-hit mouse model. By studying the independent and concomitant consequences of hypertension and obesity-driven metabolic dysfunction on cardiac structure and function, we revealed the causative drivers of cardiac functional, structural, and metabolic remodeling in male HFpEF mice. We found that hypertensive male mice developed diastolic dysfunction and cardiac hypertrophy regardless of obesity status and that obese mice exhibited altered systemic glucose metabolism and increased cardiac mitochondrial fatty-acid metabolism independent of hypertension status. Taken together, our results suggest that the cardiac structural and metabolic HFpEF symptoms in this two-hit model occur as direct results of each of the two "hits." The results of this study help to clarify the pathogenic HFpEF cascade, providing causal insights that may aid in the development of more precisely targeted therapeutics.

In the heart and beyond: Mitochondrial dysfunction in heart failure with preserved ejection fraction (HFpEF)

Heart failure with preserved ejection fraction (HFpEF) is a major cardiovascular disorder with increasing prevalence and a limited range of targeted treatment options. While HFpEF can be derived from several different etiologies, much of the current growth in the disease is being driven by metabolic dysfunction (e.g. obesity, diabetes, hypertension). Deleterious changes in mitochondrial energy metabolism are a common feature of HFpEF, and may help to drive the progression of the disease. In this brief article we aim to review various aspects of cardiac mitochondrial dysfunction in HFpEF, discuss the emerging topic of HFpEF-driven mitochondrial dysfunction in tissues beyond the heart, and examine whether supporting mitochondrial function may be a therapeutic approach to arrest or reverse disease development.

Cardiac reverse remodeling in a mouse model with many phenotypical features of heart failure with preserved ejection fraction: effects of modifying lifestyle

Multiple factors cause heart failure with preserved ejection fraction (HFpEF) and involve various systems. HFpEF prevalence is rapidly rising, and its prognosis remains poor after the first hospitalization. Adopting a more active lifestyle has been shown to provide beneficial clinical outcomes for patients with HFpEF. Using a two-hit HfpEF murine model, we studied cardiac reverse remodeling (RR) after stopping the causing stress and introducing voluntary exercise (VE). We checked in 2-mo-old male and female C57Bl6/J mice the heart's response to angiotensin II (ANG II; 1.5 mg/kg/day for 28 days) fed or not with a high-fat diet (HFD). Then, ANG II and/or the HFD were stopped, and VE was started for an additional 4 wk. ANG II and ANG II + HFD (metabolic-hypertensive stress, MHS) caused cardiac hypertrophy (CH) and myocardial fibrosis, left ventricular (LV) concentric remodeling, atrial enlargement, and reduced exercise capacity. HFD alone induced CH and LV concentric remodeling in female mice only. CH and LV concentric remodeling were reversed 4 wk after stopping ANG II, starting VE, and a low-fat diet. Left atrial enlargement and exercise capacity were improved but differed from controls. We performed bulk LV RNA sequencing and observed that MHS upregulated 58% of the differentially expressed genes (DEGs) compared with controls. In the RR group, compared with MHS animals, 60% of the DEGs were downregulated. In an HfpEF mouse model, we show that correcting hypertension, diet, and introducing exercise can lead to extensive cardiac reverse remodeling.NEW & NOTEWORTHY Using a two-hit murine model of heart failure with preserved ejection fraction (HfpEF), combining elevated blood pressure, obesity, and exercise intolerance in male and female animals, we showed that correction of hypertension, normalization of the diet, and introduction of voluntary exercise could help reverse the remodeling of the left ventricle and double exercise capacity. We also identify genes that escape normalization after myocardial recovery and differences between males' and females' responses to stress and recovery.