Developmental changes in the balance of glycolytic ATP production and oxidative phosphorylation in ventricular cells: A simulation study

Energy metabolism in health and diseases

Energy metabolism is indispensable for sustaining physiological functions in living organisms and assumes a pivotal role across physiological and pathological conditions. This review provides an extensive overview of advancements in energy metabolism research, elucidating critical pathways such as glycolysis, oxidative phosphorylation, fatty acid metabolism, and amino acid metabolism, along with their intricate regulatory mechanisms. The homeostatic balance of these processes is crucial; however, in pathological states such as neurodegenerative diseases, autoimmune disorders, and cancer, extensive metabolic reprogramming occurs, resulting in impaired glucose metabolism and mitochondrial dysfunction, which accelerate disease progression. Recent investigations into key regulatory pathways, including mechanistic target of rapamycin, sirtuins, and adenosine monophosphate-activated protein kinase, have considerably deepened our understanding of metabolic dysregulation and opened new avenues for therapeutic innovation. Emerging technologies, such as fluorescent probes, nano-biomaterials, and metabolomic analyses, promise substantial improvements in diagnostic precision. This review critically examines recent advancements and ongoing challenges in metabolism research, emphasizing its potential for precision diagnostics and personalized therapeutic interventions. Future studies should prioritize unraveling the regulatory mechanisms of energy metabolism and the dynamics of intercellular energy interactions. Integrating cutting-edge gene-editing technologies and multi-omics approaches, the development of multi-target pharmaceuticals in synergy with existing therapies such as immunotherapy and dietary interventions could enhance therapeutic efficacy. Personalized metabolic analysis is indispensable for crafting tailored treatment protocols, ultimately providing more accurate medical solutions for patients. This review aims to deepen the understanding and improve the application of energy metabolism to drive innovative diagnostic and therapeutic strategies.

Role of glycogen in cardiac metabolic stress

Metabolic stress in the myocardium arises from a diverse array of acute and chronic pathophysiological contexts. Glycogen mishandling is a key feature of metabolic stress, while maladaptation in energy-stress situations confers functional deficits. Cardiac glycogen serves as a pivotal reserve for myocardial energy, which is classically described as an energy source and contributes to glucose homeostasis during hypoxia or ischemia. Despite extensive research activity, how glycogen metabolism affects cardiovascular disease remains unclear. In this review, we focus on its regulation across myocardial energy metabolism in response to stress, and its role in metabolism, immunity, and autophagy. We further summarize the cardiovascular-related drugs regulating glycogen metabolism. In this way, we provide current knowledge for the understanding of glycogen metabolism in the myocardium.

Energy metabolism: A critical target of cardiovascular injury

Cardiovascular diseases are the main killers threatening human health. Many studies have shown that abnormal energy metabolism plays a key role in the occurrence and development of acute and chronic cardiovascular diseases. Regulating cardiac energy metabolism is a frontier topic in the treatment of cardiovascular diseases. However, we are not very clear about the choice of different substrates, the specific mechanism of energy metabolism participating in the course of cardiovascular disease, and how to develop appropriate drugs to regulate energy metabolism to treat cardiovascular disease. Therefore, this paper reviews how energy metabolism participates in cardiovascular pathophysiological processes and potential drugs aimed at interfering energy metabolism.It is expected to provide good suggestions for promoting the clinical prevention and treatment of cardiovascular diseases from the perspective of energy metabolism.

Metabolism-based cardiomyocytes production for regenerative therapy

Human pluripotent stem cells (hPSCs) are currently used in clinical applications such as cardiac regenerative therapy, studying disease models, and drug screening for heart failure. Transplantation of hPSC-derived cardiomyocytes (hPSC-CMs) can be used as an alternative therapy for heart transplantation. In contrast to differentiated somatic cells, hPSCs possess unique metabolic programs to maintain pluripotency, and understanding their metabolic features can contribute to the development of technologies that can be useful for their clinical applications. The production of hPSC-CMs requires stepwise specification during embryonic development and metabolic regulation is crucial for proper embryonic development. These metabolic features have been applied to hPSC-CM production methods, such as mesoderm induction, specifications for cardiac progenitors, and their maturation. This review describes the metabolic programs in hPSCs and the metabolic regulation in hPSC-CM production for cardiac regenerative therapy.

Antenatal Glucocorticoid Administration Promotes Cardiac Structure and Energy Metabolism Maturation in Preterm Fetuses

Although the rate of preterm birth has increased in recent decades, a number of preterm infants have escaped death due to improvements in perinatal and neonatal care. Antenatal glucocorticoid (GC) therapy has significantly contributed to progression in lung maturation; however, its potential effects on other organs remain controversial. Furthermore, the effects of antenatal GC therapy on the fetal heart show both pros and cons. Translational research in animal models indicates that constant fetal exposure to antenatal GC administration is sufficient for lung maturation. We have established a premature fetal rat model to investigate immature cardiopulmonary functions in the lungs and heart, including the effects of antenatal GC administration. In this review, we explain the mechanisms of antenatal GC actions on the heart in the fetus compared to those in the neonate. Antenatal GCs may contribute to premature heart maturation by accelerating cardiomyocyte proliferation, angiogenesis, energy production, and sarcoplasmic reticulum function. Additionally, this review specifically focuses on fetal heart growth with antenatal GC administration in experimental animal models. Moreover, knowledge regarding antenatal GC administration in experimental animal models can be coupled with that from developmental biology, with the potential for the generation of functional cells and tissues that could be used for regenerative medical purposes in the future.

Chronic hypoxia alters cardiac mitochondrial complex protein expression and activity in fetal guinea pigs in a sex-selective manner

We hypothesize that intrauterine hypoxia (HPX) alters the mitochondrial phenotype in fetal hearts contributing to developmental programming. Pregnant guinea pigs were exposed to normoxia (NMX) or hypoxia (HPX, 10.5% O2), starting at early [25 days (25d), 39d duration] or late gestation (50d, 14d duration). Near-term (64d) male and female fetuses were delivered by hysterotomy from anesthetized sows, and body/organ weights were measured. Left ventricles of fetal hearts were excised and frozen for measurement of expression of complex (I-V) subunits, fusion (Mfn2/OPA1) and fission (DRP1/Fis1) proteins, and enzymatic rates of I and IV from isolated mitochondrial proteins. Chronic HPX decreased fetal body weight and increased relative placenta weight regardless of timing. Early-onset HPX increased I, III, and V subunit levels, increased complex I but decreased IV activities in males but not females (all P < 0.05). Late-onset HPX decreased (P < 0.05) I, III, and V levels in both sexes but increased I and decreased IV activities in males only. Both HPX conditions decreased cardiac mitochondrial DNA content in males only. Neither early- nor late-onset HPX had any effect on Mfn2 levels but increased OPA1 in both sexes. Both HPX treatments increased DRP1/Fis1 levels in males. In females, early-onset HPX increased DRP1 with no effect on Fis1, whereas late-onset HPX increased Fis1 with no effect on DRP1. We conclude that both early- and late-onset HPX disrupts the expression/activities of select complexes that could reduce respiratory efficiency and shifts dynamics toward fission in fetal hearts. Thus, intrauterine HPX disrupts the mitochondrial phenotype predominantly in male fetal hearts, potentially altering cardiac metabolism and predisposing the offspring to heart dysfunction.

Energy metabolism disorders and potential therapeutic drugs in heart failure

Heart failure (HF) is a global public health problem with high morbidity and mortality. A large number of studies have shown that HF is caused by severe energy metabolism disorders, which result in an insufficient heart energy supply. This deficiency causes cardiac pump dysfunction and systemic energy metabolism failure, which determine the development of HF and recovery of heart. Current HF therapy acts by reducing heart rate and cardiac preload and afterload, treating the HF symptomatically or delaying development of the disease. Drugs aimed at cardiac energy metabolism have not yet been developed. In this review, we outline the main characteristics of cardiac energy metabolism in healthy hearts, changes in metabolism during HF, and related pathways and targets of energy metabolism. Finally, we discuss drugs that improve cardiac function via energy metabolism to provide new research ideas for the development and application of drugs for treating HF.

Resistance of Fetal Guinea Pig Ventricular Myocardium to Hypoxia: Maintained Intracellular ATP Prevents the Opening of ATP-Sensitive Potassium Channels

The presence and function of the ATP-sensitive potassium channel current (I_KATP) were examined in the guinea pig myocardium to clarify the mechanisms for the resistance of the fetal myocardium to hypoxia. Experimental hypoxia markedly reduced the action potential duration and contractile force in isolated ventricular myocardium from the adult, but only moderately in those from the fetus. In isolated ventricular cardiomyocytes, the density of the I_KATP activated by cromakalim, as well as their sensitivity to intracellular ATP concentration, were not different between the fetus and adult. The tissue ATP content was similar between the fetal and adult myocardium under normal condition, but the hypoxia-induced decrease was smaller in the fetus. Confocal microscopic analysis revealed that the mitochondria in the fetal cardiomyocyte is less in quantity than that in the adult and is more localized to the cell center. These results indicate that I_KATP in the fetal guinea pig myocardium has a current density and ATP sensitivity similar to those of the adult, but is not activated under hypoxic conditions because the energy metabolism of the fetal myocardium is less dependent on oxidative phosphorylation.