α-Ketoglutarate improves cardiac insufficiency through NAD+-SIRT1 signaling-mediated mitophagy and ferroptosis in pressure overload-induced mice

The addition of alpha-ketoglutarate to NT-proBNP improves the prediction of long-term all-cause mortality in acute heart failure patients

BACKGROUND AND OBJECTIVE

Alpha-ketoglutarate (AKG), is a major intermediate metabolite of the tricarboxylic acid cycle, and is closely associated with cardiometabolic disease prognosis. Previous studies indicated that AKG is related to myocardial energy expenditure levels and reflects adverse short-term outcomes in heart failure (HF) patients. In this prospective cohort study, we examined the long-term prognostic value of AKG levels in acute HF (AHF) patients.

METHODS

Plasma AKG levels were assessed in patients hospitalized with AHF. Hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality were calculated via multiple Cox regression. All-cause mortality was compared between patients with NT-proBNP < 1000 pg/ml and those with NT-proBNP ≥ 1000 pg/ml via subgroup analysis.

RESULTS

Patients with AKG ≥ 9.83 μg/ml had higher heart rates and NT-proBNP and lower left ventricular ejection fraction (LVEF) and systolic blood pressure (SBP). After multiple adjustment, higher AKG was associated with an increased all-cause mortality risk (HR = 1.078, p < 0.001). Compared with AKG < 9.83 μg/ml, AKG ≥ 9.83 μg/ml nearly doubled (HR = 1.929, p < 0.001) and quadrupled (HR = 4.160, p < 0.001) the all-cause mortality risk in patients with NT-proBNP ≥ 1000 pg/ml and those with NT-proBNP < 1000 pg/ml, respectively.

CONCLUSIONS AND RELEVANCE

Plasma AKG was independently associated with greater all-cause mortality risk in patients with AHF. Higher AKG levels retained prognostic value for patients with relatively low NT-proBNP.

Bergenin Alleviates Myocardial Ischemia/Reperfusion Injury via Regulating SIRT1 Through Ferroptosis

Objective

This study aimed to investigate the protective effect of bergenin on myocardial ischemia/reperfusion (I/R) injury and to elucidate its underlying mechanism.

Methods

The in vivo model of myocardial I/R injury was established by transient ligation of the left anterior descending coronary artery in Sprague-Dawley rats, which were divided into sham, I/R, I/R+bergenin, and I/R+bergenin+erastin (an agonist of ferroptosis) groups.After the model was established, the rats underwent echocardiography to assess the cardiac function. Hematoxylin and eosin (HE) staining and Masson's trichrome staining were performed to evaluate the cardiac pathological damage. Malondialdehyde (MDA), reactive oxygen species (ROS), glutathione (GSH) and iron levels were measured to determine the ferroptosis level. Western blotting was used to detect the expression of related proteins. Next, H9C2 cells were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) to mimic the in vitro model of myocardial I/R injury. EX527, a SIRT1 inhibitor, was used to further explore the role of SIRT1 in the myocardial protection of bergenin. In this part of the experiment, H9C2 cells were divided into four groups: control, OGD/R, OGD/R+bergenin, and OGD/R+bergenin+EX527.

Results

In vivo experiments, we found that the I/R group showed obvious myocardial pathological damage, oxidative stress and ferroptosis, while the bergenin pretreatment group reversed the above myocardial injury, but this protective effect was inhibited by the ferroptosis inducer erastin. In vitro experiments, compared with the OGD/R group, the bergenin group reduced the oxidative stress level, mitochondrial dysfunction and ferroptosis of H9C2 cells. We found that the protective effect of bergenin on the myocardium was abrogated by EX527. Moreover, Western blotting showed that bergenin activated SIRT1, and increased the phosphorylation of AMPK and the expression level of PGC-1α.

Conclusion

Bergenin exerted a protective effect on the myocardium by modulating the ferroptosis process during myocardial I/R injury through the SIRT1/AMPK/PGC-1α pathway.

Ferroptosis in organ fibrosis: Mechanisms and therapeutic approaches

Ferroptosis, a form of iron-dependent regulated cell death, has emerged as a critical mechanism in the pathogenesis of organ fibrosis. This review aims to provide an overview of the molecular mechanisms underlying ferroptosis and its contribution to fibrosis in various organs, including the liver, lung, heart, and kidneys. We explore how dysregulated iron metabolism, lipid peroxidation, and oxidative stress contribute to ferroptosis and subsequent tissue damage, promoting the progression of fibrosis. In addition, we highlight the complex interplay between ferroptosis and other cellular processes such as apoptosis, necrosis, and inflammation in the fibrotic microenvironment. Furthermore, this review discusses current therapeutic strategies targeting ferroptosis, including iron chelation, antioxidants, and modulators of lipid peroxidation. We also examine ongoing clinical and preclinical studies aimed at translating these findings into viable treatments for fibrotic diseases. Understanding the role of ferroptosis in organ fibrosis offers novel therapeutic opportunities, with the potential to mitigate disease progression and improve patient outcomes.

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.

The role of autophagy in fibrosis: Mechanisms, progression and therapeutic potential (Review)

Various forms of tissue damage can lead to fibrosis, an abnormal reparative reaction. In the industrialized countries, 45% of deaths are attributable to fibrotic disorders. Autophagy is a highly preserved process. Lysosomes break down organelles and cytoplasmic components during autophagy. The cytoplasm is cleared of pathogens and dysfunctional organelles, and its constituent components are recycled. With the growing body of research on autophagy, it is becoming clear that autophagy and its associated mechanisms may have a role in the development of numerous fibrotic disorders. However, a comprehensive understanding of autophagy in fibrosis is still lacking and the progression of fibrotic disease has not yet been thoroughly investigated in relation to autophagy‑associated processes. The present review focused on the latest findings and most comprehensive understanding of macrophage autophagy, endoplasmic reticulum stress‑mediated autophagy and autophagy‑mediated endothelial‑to‑mesenchymal transition in the initiation, progression and treatment of fibrosis. The article also discusses treatment strategies for fibrotic diseases and highlights recent developments in autophagy‑targeted therapies.

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.

Potential role of SIRT1 in cell ferroptosis

Ferroptosis is a novel form of cell death that uniquely requires iron and is characterized by iron accumulation, the generation of free radicals leading to oxidative stress, and the formation of lipid peroxides, which distinguish it from other forms of cell death. The regulation of ferroptosis is extremely complex and is closely associated with a spectrum of diseases. Sirtuin 1 (SIRT1), a NAD + -dependent histone deacetylase, has emerged as a pivotal epigenetic regulator with the potential to regulate ferroptosis through a wide array of genes intricately associated with lipid metabolism, iron homeostasis, glutathione biosynthesis, and redox homeostasis. This review provides a comprehensive overview of the specific mechanisms by which SIRT1 regulates ferroptosis and explores its potential therapeutic value in the context of multiple disease pathologies, highlighting the significance of SIRT1-mediated ferroptosis in treatment strategies.

Role of sirtuin 1 in depression‑induced coronary heart disease: Molecular pathways and therapeutic potential (Review)

Depression and coronary heart disease (CHD) are two interconnected diseases that profoundly impact global health. Depression is both a complex psychiatric disorder and an established risk factor for CHD. Sirtuin 1 (SIRT1) is an enzyme that requires the cofactor nicotinamide adenine dinucleotide (NAD+) to perform its deacetylation function, and its involvement is crucial in reducing cardiovascular risks that are associated with depression. SIRT1 exerts its cardioprotective effects via modulating oxidative stress, inflammation and metabolic processes, all of which are central to the pathogenesis of CHD in individuals with depression. Through influencing these pathways, SIRT1 helps to reduce endothelial dysfunction, prevent the formation of atherosclerotic plaques and stabilize existing plaques, thereby decreasing the overall risk of CHD. The present review underscores the important role of SIRT1 in serving as a therapeutic intervention molecule for tackling cardiovascular complications stemming from depression. Furthermore, it highlights the need for further studies to clarify how SIRT1 influences both depression and CHD at the molecular level. The ultimate goal of this research will be to translate these findings into practical clinical intervention strategies.

Targeting Zfp36 to combat cardiac hypertrophy: Insights into ferroptosis pathways

BACKGROUND

Cardiac hypertrophy is a precursor to heart failure and represents a significant global cause of mortality, thereby necessitating timely and effective therapeutic interventions. Zinc finger protein 36 (Zfp36) is recognised as a critical regulator of ferroptosis; however, its role and underlying mechanisms in cardiac hypertrophy remain largely unexplored. This study aims to investigate the regulatory function of Zfp36 in ferroptosis within the context of cardiac hypertrophy.

METHODS AND RESULTS

Single-cell sequencing analysis demonstrated a reduction in Zfp36 expression associated with cardiac hypertrophy. Zfp36 was observed to mitigate ferroptosis and reduce hypertrophic phenotypes in cardiomyocytes subjected to Angiotensin II (Ang II) and in myocardial tissues induced by transverse aortic constriction. The ferroptosis inhibitor Ferrostatin-1 was shown to alleviate hypertrophy when co-incubated with si-Zfp36 and Ang II. Mechanistically, Zfp36 binds to the 3' untranslated region (3'UTR) of Ythdc2 mRNA, facilitating its degradation. Ythdc2 subsequently binds to SLC7A11 mRNA, enhancing its decay, which leads to a reduction in glutathione (GSH) levels, thereby exacerbating ferroptosis and cardiac hypertrophy. Furthermore, overexpression of Ythdc2 reversed the protective effects conferred by Zfp36, while silencing of Ythdc2 counteracted the effects of Zfp36 knockdown.

CONCLUSIONS

This study elucidates the role of Zfp36 in cardiac hypertrophy, specifically detailing its modulatory mechanism via the Ythdc2/SLC7A11/GSH ferroptosis pathway. These insights lay the groundwork for innovative approaches to understanding the pathological mechanisms underlying cardiac hypertrophy and enhancing clinical interventions.

KEY POINTS

Zfp36 was initially demonstrated to attenuate cardiac hypertrophy through the inhibition of ferroptosis in cardiomyocytes, providing a new target for therapeutic strategies targeting ferroptosis. Zfp36 facilitated the degradation of Ythdc2 mRNA by binding to it, subsequently inhibiting Ythdc2-mediated degradation of SLC7A11 mRNA, and maintaining GSH levels. This elucidates a previously unrecognized regulatory pathway in the context of cardiac hypertrophy.

Exosomes derived from cardiac fibroblasts with Ang-II stimulation provoke myocardial hypertrophy via miR-15b-5p/PTEN-L axis

This study aimed to examine the impact of exosomes derived from Ang II-stimulated cardiac fibroblasts (CFs) on myocardial hypertrophy. Neonatal rat CFs were isolated and identified using Vimentin immunofluorescence. Following Ang II stimulation, exosomes were collected, characterized, and subjected to miRNA sequencing. Myocardial hypertrophy models were induced both in vitro and in vivo using Ang II. CFs were transfected with miR-15b-5p mimics or inhibitors, and their exosomes were co-cultured with rat cardiomyocytes (H9C2). Changes in cell viability, myocardial hypertrophy, and the expression levels of PTEN-L, PINK1, and Parkin proteins were assessed using the CCK-8 assay, cell surface area evaluation, and Western blot analysis. Cardiac tissue pathology and myocardial hypertrophy were evaluated through HE and WAG staining, respectively, while PTEN-L expression was detected by immunohistochemistry. The results demonstrated successful isolation of CFs and their exosomes, with miR-15b-5p significantly enriched in the exosomes derived from Ang II-stimulated CFs (Ang II-CFs-Exos). Ang II-CFs-Exos inhibited cell viability, exacerbated myocardial hypertrophy, and activated mitophagy via miR-15b-5p in the in vitro myocardial hypertrophy model. PTEN-L was identified as a downstream target of miR-15b-5p, with its overexpression reversed the effects of miR-15b-5p mimic on myocardial hypertrophy and mitophagy. Additionally, mitochondrial inhibitors also countered the effects of the miR-15b-5p mimic on myocardial hypertrophy. Furthermore, Ang II-CFs-Exos exacerbated myocardial hypertrophy in rats, while knockout of miR-15b-5p in Ang II-CFs-Exos mitigated this effect. To sum up, Ang II-CFs-Exos promote myocardial hypertrophy by modulating PINK1/Parkin signaling -mediated mitophagy through the miR-15b-5p/PTEN-L axis.

Danshen injection ameliorates unilateral ureteral obstruction-induced renal fibrosis by inhibiting ferroptosis via activating SIRT1/GPX4 pathway

Introduction

The pathogenesis of renal fibrosis is related to blood stasis, and the method of promoting blood circulation and removing blood stasis is often used as the treatment principle. Danshen injection (DSI) is a commonly used drug for promoting blood circulation and removing blood stasis in clinic. However, whether DSI slows the progression of renal fibrosis or the potential mechanism is uncertain.

Methods

We investigated renal fibrosis models using UUO mice and TGF-β stimulation in HK-2 cells.

Results

Our findings revealed that DSI or Fer-1 alleviated kidney injury by ameliorating renal morphology injury and pathological injury in vivo. Besides, DSI or Fer-1 inhibited renal fibrosis in vivo and in TGF-β-induced HK-2 cells. Furthermore, ferroptosis was lessened under DSI or Fer-1 treatment. More importantly, the DSI active ingredients (danshensu, salvianolic acid B, protocatechuic aldehyde, caffeic acid and tanshinone IIA) could bind to SIRT1. The protein levels of SIRT1 and GPX4 were downregulated accompanied by the incremental concentrations of TGF-β or Erastin, which were repaired by DSI or Fer-1 intervention. However, the inhibition of ferroptosis and renal fibrosis owing to DSI were reversed by SIRT1 inhibitor EX527.

Conclusion

Taken together, our results indicated that DSI could protect against ferroptosis to attenuate renal fibrosis by activating the SIRT1/GPX4 pathway. It is expected to be a potential agent to treat renal fibrosis.

Progress in the regulatory mechanism of mitophagy in chronic cerebral ischemic neuronal injury

Chronic cerebral ischemia (CCI) is a common clinical syndrome that can impact various cerebrovascular diseases. Its pathological mechanism of injury involves energy imbalance, oxidative stress, inflammatory response, and many other processes. Neuronal damage occurs in a complex and multifaceted manner. This article provides a detailed discussion of the activation and inhibition mechanisms of mitophagy under cerebral ischemia and considers the advantages and disadvantages of mitophagy in the recovery process of ischemic brain injury. Finally, we address the future direction of research on neuronal injury and the regulatory mechanisms of mitophagy in chronic cerebral ischemia. Future studies should focus on drug intervention at specific regulatory points and the cross-regulation of related signaling pathways to comprehensively deepen understanding of the mechanisms of neuronal injury in chronic cerebral ischemia. Promising interventions could potentially improve the treatment and outcomes of chronic cerebral ischemia.

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.

A bibliometric and visualization analysis of global research status and frontiers on autophagy in cardiomyopathies from 2004 to 2023

BACKGROUND

Autophagy is intimately associated with the development of cardiomyopathy and has received widespread attention in recent years. However, no relevant bibliometric analysis is reported at present. In order to summarize the research status of autophagy in cardiomyopathy and provide direction for future research, we conducted a comprehensive, detailed, and multidimensional bibliometric analysis of the literature published in this field from 2004 to 2023.

METHODS

All literatures related to autophagy in cardiomyopathy from 2004 to 2023 was collected from the Web of Science Core Collection, and annual papers, global publication trends, and proportion charts were analyzed and plotted using GraphPad price v8.0.2. In addition, CtieSpace [6.2.4R (64-bit) Advanced Edition] and VOSviewer (1.6.18 Edition) were used to analyze and visualize these data.

RESULTS

Two thousand two hundred seventy-nine papers about autophagy in cardiomyopathy were accessed in the Web of Science Core Collection over the last 20 years, comprising literatures from 70 countries and regions, 2208 institutions, and 10 810 authors. China contributes 56.32% of the total publications, substantially surpassing other countries, while the United States is ranked first in frequency of citations. Among the top 10 authors, six are from China, and four are from the United States. Air Force Military Medical University was the institution with the highest number of publications, while the Journal of Molecular and Cellular Cardiology (62 articles, 2.71% of the total) was the journal with the highest number of papers published in the field. Clustering of co-cited references and temporal clustering analysis showed that ferroptosis, hydrogen sulfide mitophagy, lipid peroxidation, oxidative stress, and SIRT1 are hot topics and trends in the field. The principal keywords are oxidative stress, heart, and heart failure.

CONCLUSION

The research on autophagy in cardiomyopathy is in the developmental stage. This represents the first bibliometric analysis of autophagy in cardiomyopathy, revealing the current research hotspots and future research directions in this field.

MiR-21-3p inhibitor exerts myocardial protective effects by altering macrophage polarization state and reducing excessive mitophagy

Chronic heart failure (CHF) is closely associated with inflammation and mitochondrial dysfunction in cardiomyocytes. This study attempts to investigate the effects of microRNA-21-3p (miR-21-3p) on macrophage polarization and mitophagy in CHF. Here we found miR-21-3p was upregulated in CHF and negatively correlated with carnitine palmitoyl transferase 1A (CPT1A). L-palmitoyl carnitine (L-PC) exacerbated isoproterenol (ISO)-induced myocardial structural disruption and fibrosis in rats, which was exacerbated by miR-21-3p. Mechanistically, miR-21-3p accelerated M1 macrophage polarization. Both miR-21-3p inhibitor and CPT1A overexpression suppressed mitophagy. The inhibition of CPT1A on mitophagy was reversed by miR-21-3p. MiR-21-3p targeted CPT1A mRNA and co-localized with CPT1A protein in cardiomyocytes. In the co-culture system of M1 macrophages and H9c2 cells, miR-21-3p mimics in H9c2 cells promoted M1 polarization, whereas miR-21-3p inhibitor reduced M1 phenotype. M1 macrophages exacerbated H9c2 cell damage. These findings support the potential therapeutic targeting of miR-21-3p to regulate inflammation and mitophagy by inducing CPT1A in CHF.

Epigenetic regulation of diverse regulated cell death modalities in cardiovascular disease: Insights into necroptosis, pyroptosis, ferroptosis, and cuproptosis

Cell death constitutes a critical component of the pathophysiology of cardiovascular diseases. A growing array of non-apoptotic forms of regulated cell death (RCD)-such as necroptosis, ferroptosis, pyroptosis, and cuproptosis-has been identified and is intimately linked to various cardiovascular conditions. These forms of RCD are governed by genetically programmed mechanisms within the cell, with epigenetic modifications being a common and crucial regulatory method. Such modifications include DNA methylation, RNA methylation, histone methylation, histone acetylation, and non-coding RNAs. This review recaps the roles of DNA methylation, RNA methylation, histone modifications, and non-coding RNAs in cardiovascular diseases, as well as the mechanisms by which epigenetic modifications regulate key proteins involved in cell death. Furthermore, we systematically catalog the existing epigenetic pharmacological agents targeting novel forms of RCD and their mechanisms of action in cardiovascular diseases. This article aims to underscore the pivotal role of epigenetic modifications in precisely regulating specific pathways of novel RCD in cardiovascular diseases, thus offering potential new therapeutic avenues that may prove more effective and safer than traditional treatments.

Regulated Cell Death Pathways in Pathological Cardiac Hypertrophy

Cardiac hypertrophy is characterized by an increased volume of individual cardiomyocytes rather than an increase in their number. Myocardial hypertrophy due to pathological stimuli encountered by the heart, which reduces pressure on the ventricular walls to maintain cardiac function, is known as pathological hypertrophy. This eventually progresses to heart failure. Certain varieties of regulated cell death (RCD) pathways, including apoptosis, pyroptosis, ferroptosis, necroptosis, and autophagy, are crucial in the development of pathological cardiac hypertrophy. This review summarizes the molecular mechanisms and signaling pathways underlying these RCD pathways, focusing on their mechanism of action findings for pathological cardiac hypertrophy. It intends to provide new ideas for developing therapeutic approaches targeted at the cellular level to prevent or reverse pathological cardiac hypertrophy.

SNX3 Promotes Doxorubicin-Induced Cardiomyopathy by Regulating GPX4-Mediated Ferroptosis

The complete molecular mechanism underlying doxorubicin-induced cardiomyopathy remains incompletely elucidated. In this investigation, we engineered mice with cardiomyocyte-specific sorting nexin 3 knockout (SNX3Cko ) to probe the potential protective effects of SNX3 ablation on doxorubicin-triggered myocardial injury, focusing on GPX4-dependent ferroptosis. Our findings indicate that SNX3 deletion normalized heart contractile/relaxation function and thwarted the escalation of cardiac injury biomarkers following doxorubicin exposure. Additionally, SNX3 deletion in the heart mitigated the inflammatory response and oxidative stress in the presence of doxorubicin. At the molecular level, the detrimental effects of doxorubicin-induced cell death, endoplasmic reticulum (ER) stress, and mitochondrial dysfunction were alleviated by SNX3 deficiency. Molecular analysis revealed the activation of GPX4-mediated ferroptosis by doxorubicin, whereas loss of SNX3 prevented the initiation of GPX4-dependent ferroptosis. Furthermore, treatment with erastin, a ferroptosis inducer, markedly reduced cell viability, exacerbated ER stress, and induced mitochondrial dysfunction in SNX3-depleted cardiomyocytes upon doxorubicin exposure. In summary, our results demonstrate that SNX3 deficiency shielded the heart from doxorubicin-induced myocardial dysfunction by modulating GPX4-associated ferroptosis.

Cell death‑related molecules and targets in the progression of urolithiasis (Review)

Urolithiasis is a high‑incidence disease caused by calcium oxalate (mainly), uric acid, calcium phosphate, struvite, apatite, cystine and other stones. The development of kidney stones is closely related to renal tubule cell damage and crystal adhesion and aggregation. Cell death, comprising the core steps of cell damage, can be classified into various types (i.e., apoptosis, ferroptosis, necroptosis and pyroptosis). Different crystal types, concentrations, morphologies and sizes cause tubular cell damage via the regulation of different forms of cell death. Oxidative stress caused by high oxalate or crystal concentrations is considered to be a precursor to a variety of types of cell death. In addition, complex crosstalk exists among numerous signaling pathways and their key molecules in various types of cell death. Urolithiasis is considered a metabolic disorder, and tricarboxylic acid cycle‑related molecules, such as citrate and succinate, are closely related to cell death and the inhibition of stone development. However, a literature review of the associations between kidney stone development, metabolism and various types of cell death is currently lacking, at least to the best of our knowledge. Thus, the present review summarizes the major advances in the understanding of regulated cell death and urolithiasis progression.

[Latest Findings on the Role of α-Ketoglutarate in Metabolic Syndrome]

Alpha-ketoglutarate (α-KG), an endogenous intermediate of the tricarboxylic acid cycle, is involved in a variety of cellular metabolic pathways. It serves as an energy donor, a precursor of amino acid biosynthesis, and an epigenetic regulator. α-KG plays physiological functions in immune regulation, oxidative stress, and anti-aging as well. In recent years, it has been reported that the level of α-KG in the body is closely associated with metabolic syndrome, including obesity, hyperglycemia, and other pathological factors. Exogenous supplementation of α-KG improves obesity, blood glucose levels, and cardiovascular disease risks associated with metabolic syndrome. Furthermore, α-KG regulates the common pathological mechanisms of metabolic syndrome, suggesting the potential application prospect of α-KG in metabolic syndrome. In order to provide a theoretical basis for further exploration of the application of α-KG in metabolic syndrome, we focused on α-KG and metabolic syndrome in this article and summarized the latest research progress in the role of α-KG in improving the pathological condition and disease progression of metabolic syndrome. For the next step, researchers may focus on the co-pathogenesis of metabolic syndrome and investigate whether α-KG can be used to achieve the therapeutic goal of "homotherapy for heteropathy" in the treatment of metabolic syndrome.

Novel Techniques, Biomarkers and Molecular Targets to Address Cardiometabolic Diseases

Cardiometabolic diseases (CMDs) are interrelated and multifactorial conditions, including arterial hypertension, type 2 diabetes, heart failure, coronary artery disease, and stroke. Due to the burden of cardiovascular morbidity and mortality associated with CMDs' increasing prevalence, there is a critical need for novel diagnostic and therapeutic strategies in their management. In clinical practice, innovative methods such as epicardial adipose tissue evaluation, ventricular-arterial coupling, and exercise tolerance studies could help to elucidate the multifaceted mechanisms associated with CMDs. Similarly, epigenetic changes involving noncoding RNAs, chromatin modulation, and cellular senescence could represent both novel biomarkers and targets for CMDs. Despite the promising data available, significant challenges remain in translating basic research findings into clinical practice, highlighting the need for further investigation into the complex pathophysiology underlying CMDs.

Growing concerns about using hypoxia-inducible factor prolyl hydroxylase inhibitors for the treatment of renal anemia

Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) have emerged as a novel therapeutic class for treating anemia in patients with chronic kidney disease. Small molecule analogs of α-ketoglutarate (AKG), an essential substrate for 2-oxoglutarate-dependent dioxygenases (2-OGDDs), including prolyl hydroxylase domain proteins (PHDs), inhibit PHDs pharmacologically and thereby prevent HIF degradation. HIF stabilization alleviates anemia through several stimulatory effects on erythropoiesis, but it also affects the expression of many anemia-unrelated genes whose protein products exert important functions in vivo. Therefore, the pleiotropic effects of HIF stabilization under normoxic conditions deserve to be examined in more detail. Specifically, we believe that particular attention should be given to epigenetic modifications among the various AKG-based metabolic systems that may be altered by HIF-PHIs. It is noteworthy that AKG has been reported to exert health-protective actions. AKG-based metabolic systems include enzymes associated with the tricarboxylic acid cycle and amino acid metabolism, as well as 2-OGDD-mediated processes, which play important roles in many biological reactions. In this review, we examine the multifaceted effects of HIF-PHIs, encompassing not only their on-target effect of HIF stabilization but also their off-target inhibitory effects on various AKG-based metabolic systems. Furthermore, we examine its potential relevance to cardiovascular complications, based on clinical and animal studies suggesting its involvement in vascular calcification, thrombogenesis and heart failure. In conclusion, although HIF-PHIs offer a promising avenue for anemia treatment in CKD patients, their broader impact on multiple biological systems raises substantial concerns. The intricate interplay between HIF stabilization, AKG competition and cardiovascular complications warrants extensive, long-term investigations to ensure the safety and usefulness of HIF-PHIs in clinical practice.

Cellular and Mitochondrial Pathways Contribute to SGLT2 Inhibitors-mediated Tissue Protection: Experimental and Clinical Data

In metabolic syndrome and diabetes, compromised mitochondrial function emerges as a critical driver of cardiovascular disease, fueling its development and persistence, culminating in cardiac remodeling and adverse events. In this context, angiotensin II - the main interlocutor of the renin-angiotensin-aldosterone system - promotes local and systemic oxidative inflammatory processes. To highlight, the low activity/expression of proteins called sirtuins negatively participates in these processes, allowing more significant oxidative imbalance, which impacts cellular and tissue responses, causing tissue damage, inflammation, and cardiac and vascular remodeling. The reduction in energy production of mitochondria has been widely described as a significant element in all types of metabolic disorders. Additionally, high sirtuin levels and AMPK signaling stimulate hypoxia- inducible factor 1 beta and promote ketonemia. Consequently, enhanced autophagy and mitophagy advance through cardiac cells, sweeping away debris and silencing the orchestra of oxidative stress and inflammation, ultimately protecting vulnerable tissue from damage. To highlight and of particular interest, SGLT2 inhibitors (SGLT2i) profoundly influence all these mechanisms. Randomized clinical trials have evidenced a compelling picture of SGLT2i emerging as game-changers, wielding their power to demonstrably improve cardiac function and slash the rates of cardiovascular and renal events. Furthermore, driven by recent evidence, SGLT2i emerge as cellular supermolecules, exerting their beneficial actions to increase mitochondrial efficiency, alleviate oxidative stress, and curb severe inflammation. Its actions strengthen tissues and create a resilient defense against disease. In conclusion, like a treasure chest brimming with untold riches, the influence of SGLT2i on mitochondrial function holds untold potential for cardiovascular health. Unlocking these secrets, like a map guiding adventurers to hidden riches, promises to pave the way for even more potent therapeutic strategies.