Myocardial ischaemia-reperfusion injury and cardioprotection in perspective

Dipeptidyl peptidase 3 induces myocardial ischemia-reperfusion injury by mediating mitophagy and the intrinsic apoptotic pathway

BACKGROUND

Dipeptidyl peptidase 3 (DPP3) is a zinc-dependent hydrolase that is regarded as a "myocardial inhibitor". However, the role of DPP3 in myocardial ischemia-reperfusion injury (MIRI) remain to be investigated. The present study aimed to investigate the potential role of DPP3 in MIRI and elucidate the underlying mechanisms.

METHODS

The AC16 cardiomyocyte cell line was used to investigate the interactions between DPP3 and its protein interactors, and assess its effects on the apoptosis of cardiomyocytes following oxygen glucose deprivation/reperfusion (OGD/R) treatment in vitro. An animal model of ischemia/reperfusion (I/R) injury was established using C57BL/6J mice for in vivo analyses. The role of DPP3 and the underlying mechanisms were investigated both in vitro and in vivo following DPP3 knockdown and overexpression.

RESULTS

DPP3 interacted with Parkinson's disease protein 7 (Park7), and DPP3 overexpression altered the expression levels of proteins related to the intrinsic apoptotic pathway and autophagy. This significantly downregulated the mitochondrial expression of cytochrome C, thereby exacerbating mitochondrial injury and increasing the rate of apoptosis following reperfusion. DPP3 knockdown reversed these effects; however, the simultaneous knockdown of DPP3 and Park7 did not confer the beneficial effects observed with DPP3 knockdown alone. DPP3 knockdown alleviated the extent of myocardial injury and improved cardiac function in the mouse model of I/R injury.

CONCLUSIONS

The study demonstrated that DPP3 mediates mitophagy and apoptosis in MIRI through its interaction with Park7. These findings have important implications, suggesting that targeting DPP3 and its associated signaling pathways may serve as a potential therapeutic strategy, and that the downregulation of DPP3 can potentially alleviate MIRI.

Ceria nanoparticles alleviate myocardial ischemia-reperfusion injury by inhibiting cardiomyocyte apoptosis via alleviating ROS mediated excessive mitochondrial fission

Reperfusion through thrombolytic therapy or primary percutaneous coronary intervention is commonly used to deal with acute myocardial infarction. However, the reperfusion procedure is accompanied by myocardial ischemia-reperfusion injury (MIRI). Currently, there is no therapeutics that can effectively deal with MIRI in clinical practice. Herein, the potential of ceria nanoparticles (CNPs) coated by different ligands in the treatment of rat MIRI is evaluated. The results demonstrate that CNPs can effectively modulate the oxidative stress in the heart tissue through the elimination of reactive oxygen species (ROS) and stimulation of endogenous antioxidant system. The inhibition of oxidative stress results in the reduction of p-Drp1 (Ser 616) which is critical in driving the fission and fragmentation of mitochondria. The improved mitochondrial dynamics saves the cardiomyocytes from apoptosis and reduces the acute injury of left ventricular wall during the MIRI. The ejection function of the left ventricle for both the short-term and long-term MIRI rats is well preserved. We therefore believe based on these results that the administration of CNPs is beneficial in the attenuation of MIRI during the acute stage. These findings provide useful information for the future fabrication of inorganic antioxidant nanomedicine for the treatment of MIRI.

Beyond organ isolation: The bidirectional crosstalk between cerebral and intestinal ischemia-reperfusion injury via microbiota-gut-brain axis

Ischemia-reperfusion injury (IRI) represents a pathophysiological phenomenon of profound clinical relevance that poses considerable threats to patient safety. IRI may manifest in a variety of clinical contexts including, but not limited to, sepsis, organ transplantation, shock, myocardial infarction, cerebral ischemia, and stroke. Critically, IRI exhibits complex interactions across different organs, with effects that surpass mere localized tissue damage. These impacts can amplify damage to both adjacent and remote organs through pathways such as the gut-brain axis and the gut-lung axis, facilitated by intricate signaling mechanisms. Noteworthy is the interaction between gut IRI and brain IRI, which involves sophisticated neuroendocrine, systemic, and immune mechanisms coordinated through the microbiome-gut-brain axis. This review seeks to delve into the intricate interactions between gut and brain IRI, viewed through the lens of the microbiota-gut-brain axis. It aims to assess its translational potential in clinical settings, provide a theoretical foundation for developing relevant therapeutic strategies, and pinpoint novel directions for research.

Estrogen mitigates ischemia-reperfusion injury by inhibiting cardiomyocyte ferroptosis through the downregulation of PHLDA3 expression

Ferroptosis represents a significant target for mitigating myocardial ischemia-reperfusion (I/R) injury. Existing literature indicates that estrogen (17β-estradiol, E2) can alleviate such injuries through various pathways. However, the specific mechanisms by which E2 may confer protection against myocardial I/R injury through the inhibition of ferroptosis remain to be fully elucidated. This study employed a mouse model of left anterior descending coronary artery ligation to investigate the protective effects of E2 on myocardial I/R injury, with a particular focus on its inhibitory effects on ferroptosis and PHLDA3 in both hypoxia-reoxygenation (H/R) and I/R models. A bioinformatics analysis was conducted to evaluate the impact of estrogen receptor GPER knockout on PHLDA3 expression and ferroptosis. Loss-of-function approaches were employed to elucidate the role of PHLDA3 in ferroptosis during myocardial I/R injury. Our findings demonstrate that E2 can ameliorate myocardial I/R injury, primarily by inhibiting ferroptosis. Notably, PHLDA3 expression levels were significantly elevated during ischemia-reperfusion events; however, E2 was observed to suppress this expression. Bioinformatics analysis indicated that PHLDA3 levels increased following GPER knockdown, and the inhibitory effect of E2 on PHLDA3 expression could be partially reversed by GPER inhibitors (G15) in animal models. Furthermore, the suppression of PHLDA3 reduced ferroptosis and mitigated the severity of myocardial I/R injury. Utilizing mass spectrometry and co-immunoprecipitation methodologies, we have elucidated a potential mechanism in which PHLDA3 directly binds to and interacts with proteins involved in the process of ferroptosis. Our findings demonstrate that E2 effectively suppresses ferroptosis and mitigates myocardial I/R injury by downregulating PHLDA3 expression through the activation of the GPER receptor.

Regulation of N-Glycosylation of CDNF on Its Protein Stability and Function in Hypoxia/Reoxygenation Model of H9C2 Cells

Myocardial ischemia-reperfusion (I/R) injury is a cause of high post-interventional mortality in patients with acute myocardial infarction (MI). Cerebral dopamine neurotrophic factor (CDNF) is an endoplasmic reticulum (ER) resident protein, and its expression and secretion are induced when tissues and cells are subjected to hypoxia, ischemia, or traumatic injury. As a novel cardiomyokine, CDNF plays a crucial role in the progression of myocardial I/R injury. In our previous study, we reported that the overexpression of CDNF inhibited tunicamycin-induced H9C2 cell apoptosis. Moreover, there is a unique N-glycosylation site at Asn57 in the CDNF protein, which likely affects its function in H9C2 cells. However, the detailed impact remains unexplored. In our current study, we observed elevated levels of CDNF in the serum of acute MI patients, myocardial tissue of I/R model mice, and H/R model H9C2 cells. To detect the effect of N-glycosylation on the CDNF protein, we constructed an Asn57 mutant (N57A) plasmid and found that the N57A protein presented similar intracellular localization to those of the wild-type CDNF protein. However, the N57A protein demonstrated reduced stability, and the mutant protein could not protect H/R-induced H9C2 cells from apoptosis. Moreover, this process may occur through the downregulation of the PI3K/Akt pathway. Therefore, N-glycosylation of CDNF may be essential for protein stability and its protective role in H/R injury in H9C2 cells.

Cardioprotection by poloxamer 188 is mediated through increased endothelial nitric oxide production

Ischemia/reperfusion (I/R) injury significantly contributes to the morbidity and mortality associated with cardiac events. Poloxamer 188 (P188), a non-ionic triblock copolymer, has been proposed to mitigate I/R injury by stabilizing cell membranes. However, the underlying mechanisms remain incompletely understood, particularly concerning endothelial cell (EC) function and nitric oxide (NO) production. We employed human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (CMs) and ECs to elucidate the effects of P188 on cellular survival, function, and NO secretion under simulated I/R conditions. iPSC-CMs contractility and iPSC-ECs' NO production were assessed following exposure to P188. Further, an isolated heart model using Brown Norway rats subjected to I/R injury was utilized to evaluate the ex-vivo cardioprotective effects of P188, examining cardiac function and NO production, with and without the administration of a NO inhibitor. In iPSC-derived models, P188 significantly preserved CM contractile function and enhanced cell viability after hypoxia/reoxygenation. Remarkably, P188 treatment led to a pronounced increase in NO secretion in iPSC-ECs, a novel finding demonstrating endothelial protective effects beyond membrane stabilization. In the rat isolated heart model, administration of P188 during reperfusion notably improved cardiac function and reduced I/R injury markers. This cardioprotective effect was abrogated by NO inhibition, underscoring the pivotal role of NO. Additionally, a dose-dependent increase in NO production was observed in non-ischemic rat hearts treated with P188, further establishing the critical function of NO in P188 induced cardioprotection. In conclusion, our comprehensive study unveils a novel role of NO in mediating the protective effects of P188 against I/R injury. This mechanism is evident in both cellular models and intact rat hearts, highlighting the potential of P188 as a therapeutic agent against I/R injury. Our findings pave the way for further investigation into P188's therapeutic mechanisms and its potential application in clinical settings to mitigate I/R-related cardiac dysfunction.

Cardiomyocyte-specific NHE1 overexpression confers protection against myocardial infarction during hyperglycemia

BACKGROUND

Acute hyperglycemia on admission is frequently observed during the early phase after acute myocardial infarction (MI), even without the history of diabetes mellitus. We previously reported that inhibiting Na+/H+ exchanger 1 (NHE1) activity post-MI may improve outcomes, but not in the setting of MI with acute hyperglycemia. However, the precise role of NHE1 in the pathophysiology of MI with acute hyperglycemia remains to be elucidated, and there are no effective strategies for its prevention or treatment.

METHODS AND RESULTS

We analyzed 85 post-MI patients, identifying acute hyperglycemia (glucose > 7 mM) in non-diabetic individuals, linked to elevated BNP, CK-MB, and reduced plasma Na+. Using retrospective cohort studies and MI with acute hyperglycemia mouse models, we demonstrated that hyperglycemia exacerbates myocardial injury by reducing extracellular Na+, increasing intracellular Na+, and elevating pH, suggesting NHE1 activation as inferred from the observed intracellular pH (pHi) shift. Cardiomyocyte-specific NHE1 ablation or pharmacological inhibition worsened cardiac dysfunction and fibrosis in MI with acute hyperglycemia, while NHE1 overexpression conferred protection. RNA sequencing and drug screening identified accelerated NHE1 activation via 3% NaCl and lithospermic acid (LA) as a novel strategy to mitigate cardiomyocyte necroptosis, alleviating ischemic injury in MI and ischemia reperfusion models. Hypoxia-hyperglycemia and necroptosis induction models in NHE1-knockout, NHE1-overexpressing, and MLKL-overexpressing cardiomyocytes revealed that NHE1 activation, unlike its protective role in oxygen-glucose deprivation, promotes MLKL degradation via autophagosome-lysosomal pathways, reducing cardiomyocyte death. MLKL knockout and MLKL-NHE1 double knockout mice confirmed that MLKL ablation counteracts NHE1 inhibition's detrimental effects.

CONCLUSIONS

Activation of myocardial NHE1 promotes MLKL autophagic degradation, mitigating cardiomyocyte necroptosis and acute hyperglycemia-exacerbated MI, highlighting NHE1 as a hyperglycemia-dependent cardioprotective target. Moderate NHE1 activation may represent a novel therapeutic strategy for MI with acute hyperglycemia.

STING aggravates ferroptosis-dependent myocardial ischemia-reperfusion injury by targeting GPX4 for autophagic degradation

Despite advancements in interventional coronary reperfusion technologies following myocardial infarction, a notable portion of patients continue to experience elevated mortality rates as a result of myocardial ischemia-reperfusion (MI/R) injury. An in-depth understanding of the mechanisms underlying MI/R injury is crucial for devising strategies to minimize myocardial damage and enhance patient survival. Here, it is discovered that during MI/R, double-stranded DNA (dsDNA)-cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signal accumulates, accompanied by high rates of myocardial ferroptosis. The specific deletion of cgas or Sting in cardiomyocytes, resulting in the inhibition of oxidative stress, has been shown to mitigate ferroptosis and I/R injury. Conversely, activation of STING exacerbates ferroptosis and I/R injury. Mechanistically, STING directly targets glutathione peroxidase 4 (GPX4) to facilitate its degradation through autophagy, by promoting the fusion of autophagosomes and lysosomes. This STING-GPX4 axis contributes to cardiomyocyte ferroptosis and forms a positive feedback circuit. Blocking the STING-GPX4 interaction through mutations in T267 of STING or N146 of GPX4 stabilizes GPX4. Therapeutically, AAV-mediated GPX4 administration alleviates ferroptosis induced by STING, resulting in enhanced cardiac functional recovery from MI/R injury. Additionally, the inhibition of STING by H-151 stabilizes GPX4 to reverse GPX4-induced ferroptosis and alleviate MI/R injury. Collectively, a novel autophagy-dependent ferroptosis mechanism is identified in this study. Specifically, STING autophagy induced by anoxia or ischemia-reperfusion leads to GPX4 degradation, thereby presenting a promising therapeutic target for heart diseases associated with I/R.

E3 ubiquitin ligase CHIP alleviates H/R-induced myocardial injury by inhibiting pyroptosis

BACKGROUND

Hypoxia/Reoxygenation (H/R) injury to cardiomyocytes has adverse effects on the function, structure and prognosis of the heart. Studies have shown that H/R injury is closely related to pyroptosis. The inflammatory response induced by pyroptosis, leading to the death of cardiomyocytes. However, the specific mechanism of pyroptosis in myocardial H/R injury is not fully understood. In recent years, the important role of CHIP proteins in cardiovascular diseases has gradually attracted attention. Studies have found that CHIP protein can play an important role in the regulation of pyroptosis. However, its role in ameliorating H/R injury in cardiomyocytes has not been fully studied.

METHODS

An in vitro H/R model was constructed, and CHIP was knockdown and overexpression interfered simultaneously. The effect of CHIP on pyroptosis and its reduction of H/R-induced myocardial injury were verified by detection of cell viability, LDH, cell membrane integrity, ROS production, inflammatory factors (NLRP3, Caspase-1, ASC, IL-1β) and β-catenin/HSF1 signaling pathway.

RESULTS

In our study, we verified that the occurrence of oxidative stress and pyroptosis as well as cell damage was significantly increased in cardiomyocytes after H/R stimulation in vitro. After CHIP knockdown, pyroptosis of cardiomyocytes was further aggravated, accompanied by the down-regulation of HSF1/β-catenin signaling axis. These adverse changes were ameliorated after CHIP overexpression.

CONCLUSION

Our study confirmed that CHIP can alleviate H/R-induced myocardial injury by mediating pyroptosis, which may be achieved by regulating HSF1/β-catenin signaling pathway.

Tyrosine phosphorylation of Kir6.2 subunit negatively regulates cardiac KATP channel activity

The plasma membrane ATP-sensitive potassium (KATP) channel in cardiac myocytes plays a critical role in protecting the heart against ischemic injury. Post-translational modifications regulate KATP channel activity and play a role in cardioprotection. However, the role of tyrosine phosphorylation in KATP channel regulation remains unclear. In this study, we investigated the cardiac KATP channel subtype Kir6.2/SUR2A and demonstrated that a protein tyrosine kinase inhibitor significantly increased the current amplitude through blunting the ATP sensitivity of KATP channels without altering the single-channel current or the channel surface expression. Mutation screening identified Y258 in the Kir6.2 subunit as the tyrosine phosphorylation site of the KATP channel. In cardiomyocytes, KATP channel currents can be reversibly enhanced or weakened by inhibiting the tyrosine kinase epidermal growth factor receptor or the protein tyrosine phosphatase 1B. Furthermore, in a perfused mouse heart model, the inhibitor of epidermal growth factor receptor exhibited a significant cardioprotective effect in a KATP channel dependent manner, indicating the pharmacological potential for treatment of ischemic heart disease.

The Regulatory Role of NcRNAs in Pyroptosis and Disease Pathogenesis

Non-coding RNAs (ncRNAs), as critical regulators of gene expression, play a pivotal role in the modulation of pyroptosis and exhibit a close association with a wide range of diseases. Pyroptosis is a form of programmed cell death mediated by inflammasomes, characterized by cell membrane perforation, release of inflammatory cytokines, and a robust immune response. Recent studies have revealed that ncRNAs influence the initiation and execution of pyroptosis by regulating the expression of pyroptosis-related genes or modulating associated signaling pathways. This review systematically summarizes the molecular mechanisms and applications of ncRNAs in diseases such as cancer, infectious diseases, neurological disorders, cardiovascular diseases, and metabolic disorders. It further explores the potential of ncRNAs as diagnostic biomarkers and therapeutic targets, elucidates the intricate interactions among ncRNAs, pyroptosis, and diseases, and provides novel strategies and directions for the precision treatment of related diseases.

Semen Ziziphi Spinosae alleviates cardiomyocyte apoptosis in rats with coronary heart disease via the AMPK/SIRT1/PGC-1α signaling pathway activation

BACKGROUND

Coronary heart disease (CHD) represents a significant cardiovascular condition, with its occurrence increasing as a result of alterations in lifestyle and dietary habits. Semen Ziziphi Spinosae (SZS) is commonly utilized for the management of disorders associated with the nervous system, including conditions like depression and insomnia. Recent research has revealed its potential therapeutic properties for cardiovascular issues. Nevertheless, there exists a limited amount of research addressing the mechanisms involved.

PURPOSE

This research seeks to explore the protective effects that SZS has on cardiac tissue, specifically within the framework of CHD. By conducting this investigation, the study aims to uncover the various mechanisms that play a role in these protective effects. This understanding could yield significant insights into how SZS may result in the preservation and enhancement of cardiac health in patients affected by CHD.

STUDY DESIGN

The study innovatively combines multiple advanced techniques. It first integrates UPLC-Q-TOF/MS analysis and network pharmacology to identify SZS components. In vitro experiments were conducted using H9c2 rat cardiomyocytes, and in vivo experiments used a CHD model in SD rats. Multiple assays were performed for multi - level and multi - dimensional validation.

METHODS

In the initial stage, the primary components of SZS and their possible mechanisms for combating CHD were examined through UPLC-Q-TOF/MS analysis in conjunction with network pharmacology approaches. For the in vitro investigation, an ischemia-hypoxia model was established utilizing H9c2 rat cardiomyocytes. The CCK-8 assay was used to assess myocardial injury markers. TUNEL staining and Western blot techniques were employed to confirm the impact of SZS treatment on apoptosis in H9c2 cells. The expression levels of proteins associated with the AMPK/SIRT1/PGC-1α signaling pathway were measured using RT-qPCR and Western blotting, and the results were validated with the AMPK inhibitor, compound C. In the in vivo segment, a model of coronary heart disease (CHD) in SD rats was established through the administration of a high-fat emulsion diet combined with pituitrin injections. Cardiac function in the rats was evaluated through electrocardiograms and echocardiograms. Pathological changes in the heart were observed utilizing TTC and H&E staining. Kits were implemented to measure the serum biochemical indicators in the rats.RT - qPCR and Western blotting were employed to measure the expression levels of proteins related to the AMPK/SIRT1/PGC - 1α signaling pathway.

RESULTS

The study identified 67 in vitro components, 27 blood - absorbed components, and 12 metabolic components of SZS. Network pharmacology analysis suggested the AMPK/SIRT1/PGC - 1α signaling pathway as a key mechanism. In vitro and in vivo experiments showed that SZS increased cell viability, reduced apoptosis, and activated the AMPK/SIRT1/PGC - 1α signaling pathway. Inhibiting AMPK abolished SZS's effects. SZS also improved cardiac function and reduced myocardial damage in rats with CHD.

CONCLUSION

This study for the first time highlights that Semen Ziziphi Spinosae plays a beneficial role in cardiovascular health by activating the AMPK/SIRT1/PGC-1α signaling pathway and reducing apoptosis in cardiomyocytes. These findings support its potential application in the treatment of CHD and other cardiac conditions.

Materials Advances in Devices for Heart Disease Interventions

Heart disease encompasses a range of conditions that affect the heart, including coronary artery disease, arrhythmias, congenital heart defects, heart valve disease, and conditions that affect the heart muscle. Intervention strategies can be categorized according to when they are administered and include: 1) Monitoring cardiac function using sensor technology to inform diagnosis and treatment, 2) Managing symptoms by restoring cardiac output, electrophysiology, and hemodynamics, and often serving as bridge-to-recovery or bridge-to-transplantation strategies, and 3) Repairing damaged tissue, including myocardium and heart valves, when management strategies are insufficient. Each intervention approach and technology require specific material properties to function optimally, relying on materials that support their action and interface with the body, with new technologies increasingly depending on advances in materials science and engineering. This review explores material properties and requirements driving innovation in advanced intervention strategies for heart disease and highlights key examples of recent progress in the field driven by advances in materials research.

Impact of chronic hyperglycaemia on the coronary microcirculation - benefits of targeting IL-36 and diet reversal

Following myocardial infarction (MI), patients with type 2 diabetes mellitus (T2DM) have poorer prognosis which may be linked to increased susceptibility of coronary microvessels to injury. Interleukin-36 (IL-36) may mediate this injury but its role in the microcirculation of the chronically hyperglycaemic injured heart is unknown. Intravital and laser speckle imaging of the anaesthetised mouse beating heart evaluated the impact of a 16-week high fat diet (HFD)-induced hyperglycaemia ± myocardial ischaemia-reperfusion injury (IR) injury on coronary microvessels. Neutrophil/platelet recruitment, neutrophil extracellular trap formation, cellular necrosis, vascular leakage, vascular tonal changes, functional capillary density, overall ventricular perfusion and levels of circulating inflammatory cytokines were assessed alongside the vasculoprotective ability of an IL-36 receptor antagonist (IL-36Ra). Whether heightened microvessel damage in injured HFD mice was permanent or reversible was investigated after normalising hyperglycaemia through diet reversal (DR). Microcirculatory events assessed were perturbed basally in HFD mice and further after injury. IL-36Ra mitigated these effects and improved infarct size. DR was also beneficial, decreasing neutrophil recruitment to levels below those seen in untreated mice. Mechanistically, benefits of both IL-36Ra and DR could be explained by decreased endothelial oxidative stress and VCAM-1 expression and possibly by raised levels of IL-4/IL-13. Basal changes in chronically hyperglycaemic coronary microvessels that are heightened in the aftermath of reperfusion may explain the poorer outcomes in MI patients with T2DM. These findings are the first to highlight the specific benefits of IL-36 inhibition and reversing hyperglycaemia through dietary modification on the coronary microcirculation in a preclinical model of T2DM.

Progress in the study of the mechanism of ferroptosis in coronary heart disease and clinical intervention strategies

Coronary heart disease (CHD), a serious cardiovascular condition with complex and diverse pathogenesis, has recently seen increased attention to the role of ferroptosis-a novel iron-dependent form of programmed cell death. This review synthesizes current research on ferroptosis mechanisms in CHD and emerging clinical intervention strategies. Ferroptosis is characterized by dysregulated iron metabolism, lipid peroxidation, and reactive oxygen species (ROS) accumulation, processes intimately linked to CHD pathophysiology. Under ischemic and hypoxic conditions commonly seen in coronary artery disease (CAD), cardiomyocytes become particularly susceptible to ferroptosis, resulting in cellular dysfunction and diminished cardiac performance. Mechanistic studies have revealed that altered expression of iron metabolism-related proteins (including GPX4, FTH1, TfR1, and HO-1), accumulation of lipid peroxidation products, and disruption of antioxidant defense systems (particularly the Nrf2/GPX4 pathway) are central to ferroptosis progression in cardiac tissue. Clinically, both specific ferroptosis inhibitors (such as Ferrostatin-1) and traditional medicine components (such as Puerarin) have emerged as promising therapeutic candidates, showing cardioprotective effects in experimental models. However, research into ferroptosis mechanisms in CHD remains in its early stages, with significant questions regarding its relationship with other cell death pathways and the clinical efficacy of ferroptosis-targeting interventions requiring further investigation. Future research directions should include in-depth mechanistic exploration and the development of more effective, safer clinical interventions targeting the ferroptosis pathway in cardiovascular disease.

Slack K+ channels confer protection against myocardial ischaemia/reperfusion injury

AIMS

Na+-activated Slack potassium (K+) channels are increasingly recognized as regulators of neuronal activity, yet little is known about their role in the cardiovascular system. Slack activity increases when intracellular Na+ concentration ([Na+]i) reaches pathophysiological levels. Elevated [Na+]i is a major determinant of the ischaemia and reperfusion (I/R)-induced myocardial injury; thus, we hypothesized that Slack plays a role under these conditions.

METHODS AND RESULTS

K+ currents in cardiomyocytes (CMs) obtained from wildtype but not from global Slack knockout mice were sensitive to electrical inactivation of voltage-sensitive Na+ channels. Live-cell imaging demonstrated that K+ fluxes across the sarcolemma rely on Slack, while the depolarized resting membrane potential in Slack-deficient CMs led to excessive cytosolic Ca2+ accumulation and finally to hypoxia/reoxygenation-induced cell death. Cardiac damage in an in vivo model of I/R was exacerbated in global and CM-specific conditional Slack mutants and largely insensitive to mechanical conditioning manoeuvres. Finally, the protection conferred by mitochondrial ATP-sensitive K+ (mitoKATP) channels required functional Slack in CMs.

CONCLUSION

Collectively, our study provides evidence for Slack's crucial involvement in the ion homeostasis of no or low O2-stressed CMs. Thereby, Slack activity opposes the I/R-induced fatal Ca2+-uptake to CMs supporting the cardioprotective signaling attributed to mitoKATP function.

Gold-modified nanoporous silicon for photoelectrochemical regulation of intracellular condensates

Nano-enabled catalysis at the interface of metals and semiconductors has found numerous applications, but its role in mediating cellular responses is still largely unexplored. Here we explore the territory by examining the once elusive mechanism through which a nanoporous silicon-based photocatalyst facilitates the two-electron oxidation of water to generate hydrogen peroxide under physiological conditions. We achieve precise modulation of intracellular stress granule formation by the controlled photoelectrochemical production of hydrogen peroxide in the extracellular environment, thereby enhancing cellular resilience to significant oxidative stress. This photoelectrochemical strategy has been evaluated for its efficacy in treating myocardial ischaemia-reperfusion injury in an ex vivo rodent model. Our data suggest that a pretreatment regimen involving photoelectrochemical generation of hydrogen peroxide at mild concentrations mitigates myocardial ischaemia-reperfusion-induced functional decline and infarction. These findings suggest a viable wireless therapeutic intervention for managing ischaemic disease and highlight the biomedical potential of nanostructured semiconductor-based catalytic devices.

Effectiveness of psychological interventions in reducing post-traumatic stress among post-myocardial infarction patients: a systematic review and meta-analysis

AIMS

Myocardial infarction (MI) can lead to post-traumatic stress disorder (PTSD) which frequently occurs with anxiety and depression, impairing daily functioning and increasing the risk of recurrent cardiovascular events. While psychological interventions have shown promise in reducing anxiety and depression, their effectiveness for PTSD in post-MI patients remains unexplored. This systematic review and meta-analysis aim to evaluate the effectiveness of psychological interventions on PTSD, anxiety, and depression in post-MI patients.

METHODS AND RESULTS

A comprehensive search of databases (Cochrane, CINAHL, PubMed, PsycINFO, Scopus, Embase, Web of Science, CNKI, Wanfang, CBM, ProQuest Dissertations and Theses Global, ClinicalTrials.gov) was conducted until June 2024, identifying randomized controlled trials and quasi-experimental studies assessing psychological interventions in post-MI patients. Study quality was evaluated using the Cochrane Risk of Bias and ROBINS-I tools. Post-traumatic stress disorder outcomes were pooled using meta-analysis in RevMan 5.4. Narrative synthesis was conducted where meta-analysis was not feasible. Nine studies involving 1065 participants were included. Psychological interventions significantly reduced PTSD symptoms {standardized mean difference (SMD) = -0.43 [95% confidence interval (CI): -0.70 to -0.16, P = 0.002]}, anxiety, and depression post-intervention. Subgroup analyses found that intervention components influenced effectiveness, with first-line treatments [eye movement desensitization and reprocessing (EMDR) and cognitive-behavioural therapy (CBT)] demonstrating a medium effect (SMD = -0.40; 95% CI: -0.74 to -0.07; P = 0.02). No significant subgroup differences were found based on the control condition or geographical location of studies.

CONCLUSION

Psychological interventions, particularly CBT and EMDR, were effective in alleviating PTSD, anxiety, and depression in post-MI patients. Future high-quality research is needed to identify active components and optimize these psychological interventions.

REGISTRATION

Prospero CRD42024528138.

Hydroxysafflor yellow A for ischemic heart diseases: a systematic review and meta-analysis of animal experiments

Background

Hydroxysafflor yellow A (HSYA) possesses a variety of pharmacological activities which has been demonstrated to be effective against ischemic heart disease (IHD). This study aimed to comprehensively examine the efficacy and summarize the potential mechanisms of HSYA against IHD in animal models.

Methods

We conducted electronic searches for preclinical studies on PubMed, Embase, Web of Science, Cochrane Library, CNKI, SinoMed, Wanfang, and Chinese VIP databases from inception to 31 January 2024. The CAMARADES checklist was chosen to assess the quality of evidence. STATA 14.0 software was utilized to analyze the data. The underlying mechanisms were categorized and summarized.

Results

Twenty-eight studies involving 686 rodents were included and the mean score of methodology quality was 5.04 (range from 4 to 7). Meta-analysis observed that HSYA could decrease myocardial infarction size (SMD: -2.82, 95%CI: -3.56 to -2.08, p < 0.001) and reduce the levels of biomarkers of myocardial injury including cTnI (SMD: -3.82, 95%CI: -5.20 to -2.44, p < 0.001) and CK-MB (SMD: -2.74, 95%CI: -3.58 to -1.91, p < 0.001). HSYA displayed an improvement in cardiac function indicators including LVEF, LVSP, +dp/dt max and -dp/dt max. Furthermore, HSYA was able to reduce the levels of MDA, TNF-α and IL-6, while increasing SOD and NO levels. Mechanistically, the protective effect of HSYA in alleviating myocardial injury after ischemia may be associated with NLRP3 inflammasome, Bcl-2, Bax, caspase-3, eNOS proteins, and TLR/NF-κB, Nrf2/HO-1, JAK/STAT, PI3K/Akt, AMPK/mTOR, VEGFA pathways.

Conclusion

This study demonstrates that HSYA exerts cardioprotective effects in decreasing infarct size, reducing myocardial enzymes and improving cardiac function, which may be mediated by anti-inflammatory, antioxidant, anti-apoptotic, regulation of autophagy, improvement of microcirculation and promotion of angiogenesis. However, the absence of safety assessment, lack of animal models of co-morbidities, and inconsistency between timing of administration and clinical practice are limitations of preclinical studies.

Systematic Review Registration

clinicaltrials.gov, Identifier, CRD42023460790.

Shengmai-Yin resists myocardial ischemia reperfusion injury by inhibiting K27 ubiquitination of absent in melanoma 2

ETHNOPHARMACOLOGICAL RELEVANCE

Myocardial ischemia-reperfusion (I/R) injury stands as a significant contributor to cardiovascular disease. Shengmai-Yin (SMY), a traditional Chinese medicine, is widely used in myocardial infarct treatment. However, the specific mechanism of SMY in treating myocardial I/R injury is currently limited.

AIM OF STUDY

The study aimed to investigate the therapeutic efficacy of SMY in addressing myocardial I/R injury and elucidate its specific mechanisms.

MATERIALS AND METHODS

The active components of SMY were quantified using Ultra-high performance liquid chromatography-MS/MS (UPLC-MS/MS). Sprague-Dawley (SD) rats were treated with SMY post-I/R model establishment. Cardiac injury was assessed by heart weight to body weight ratio. Left ventricular function and infarct volume were evaluated using ultrasound cardiography and TTC staining. Tissue lesions were examined via hematoxylin-eosin (HE) and Sirius Red staining. Co-Immunoprecipitation (Co-IP) technology explored absent in melanoma 2 (AIM2) and K27 Ubiquitination Modification (K27-Ub) interactions. Immunofluorescence staining detected Apoptosis-associated Speck-like Protein containing a CARD (ASC) and AIM2 co-localization. Adeno-associated Virus (AAV) was used to upregulate AIM2 levels, while Shikonin was used to downregulate AIM2, to explore its roles in SMY's therapeutic effects on I/R injury.

RESULTS

SMY can reduce infarct size and enhance cardiac function. Furthermore, SMY can inhibit tissue fibrosis. Fibrosis markers and proinflammatory factors were reduced after SMY treatment. Serum levels of Lactate Dehydrogenase (LDH) and Creatine Kinase -MB (CK-MB) were also decreased. Mechanistically, SMY inhibits the activation of the AIM2 inflammasome by downregulating the K27 ubiquitination of AIM2. Overexpression of AIM2 reversed the anti-I/R effect of SMY, suggesting that AIM2 plays a crucial role in I/R injury. The AIM2 inhibitor counteracts the therapeutic effect of SMY.

CONCLUSION

SMY inhibits the K27 ubiquitination modification of AIM2 and inhibits the activation of AIM2 inflammasomes after myocardial I/R injury.

Nrf3-Mediated Mitochondrial Superoxide Promotes Cardiomyocyte Apoptosis and Impairs Cardiac Functions by Suppressing Pitx2

BACKGROUND

Myocardial infarction (MI) elicits mitochondria reactive oxygen species (ROS) production and cardiomyocyte (CM) apoptosis. Nrf3 (nuclear factor erythroid 2-related factor 3) has an established role in regulating redox signaling and tissue homeostasis. Here, we aimed to evaluate the role and mechanism of Nrf3 in injury-induced pathological cardiac remodeling.

METHODS

Global (Nrf3-KO) and CM-specific (Nrf3△CM) Nrf3 knockout mice were subjected to MI or ischemia/reperfusion injury, followed by functional and histopathological analysis. Primary neonatal mouse and rat ventricular myocytes and CMs derived from human induced pluripotent stem cells were used to evaluate the impact of Nrf3 on CM apoptosis and mitochondrial ROS production. Chromatin immunoprecipitation sequencing and immunoprecipitation-mass spectrometry analysis were used to uncover potential targets of Nrf3. MitoParaquat administration and CM-specific adeno-associated virus vectors were used to further confirm the in vivo relevance of the identified signal pathways.

RESULTS

Nrf3 was expressed mainly in CMs in healthy human hearts, and an increased level of Nrf3 was observed in CMs within the border zone of infarcted human hearts and murine cardiac tissues after MI. Both global and CM-specific Nrf3 knockout significantly decreased injury-induced mitochondrial ROS production, CM apoptosis, and pathological cardiac remodeling, consequently improving cardiac functions. In addition, cardiac-specific Nrf3 overexpression reversed the ameliorative cardiac phenotypes observed in Nrf3-KO mice. Functional studies showed that Nrf3 promoted neonatal mouse ventricular myocyte, neonatal rat ventricular myocyte, and CMs derived from human induced pluripotent stem cell apoptosis by increasing mitochondrial ROS production. Critically, augmenting mitochondrial ROS with MitoParaquat blunted the beneficial effects of Nrf3 deletion on cardiac function and remodeling. Mechanistically, a redox regulator Pitx2 (paired-like homeodomain transcription factor 2) was identified as one of the main target genes of Nrf3. Specifically, Nrf3 binds to Pitx2 promoter, where it increases DNA methylation through recruiting heterogeneous nuclear ribonucleoprotein K and DNA-methyltransferase 1 complex, thereby inhibiting Pitx2 expression. CM-specific knockdown of Pitx2 blunted the beneficial effects of Nrf3 deletion on cardiac function and remodeling, and cardiac-specific Pitx2 overexpression attenuated MI-induced mitochondrial ROS production and CM apoptosis, as well as preserved cardiac functions after MI.

CONCLUSIONS

Nrf3 promotes injury-induced CM apoptosis and deteriorates cardiac functions by increasing mitochondrial ROS production through suppressing Pitx2 expression. Targeting the Nrf3-Pitx2-mitochondrial ROS signal axis may therefore represent a novel therapeutic approach for MI treatment.

Pericytes in the brain and heart: functional roles and response to ischaemia and reperfusion

In the last 20 years, there has been a revolution in our understanding of how blood flow is regulated in many tissues. Whereas it used to be thought that essentially all blood flow control occurred at the arteriole level, it is now recognized that control of capillary blood flow by contractile pericytes plays a key role both in regulating blood flow physiologically and in reducing it in clinically relevant pathological conditions. In this article, we compare and contrast how brain and cardiac pericytes regulate cerebral and coronary blood flow, focusing mainly on the pathological events of cerebral and cardiac ischaemia. The cerebral and coronary capillary beds differ dramatically in morphology, yet in both cases, pericyte-mediated capillary constriction plays a key role in restricting blood flow after ischaemia and possibly in other pathological conditions. We conclude with suggestions for therapeutic approaches to relaxing pericytes, which may prove useful in the long-term for reducing pericyte-induced ischaemia.

Comparison of the proteomic landscape in experimental ischemia reperfusion with versus without ischemic preconditioning

Myocardial ischemic preconditioning (IPC) enhances myocardial resilience to ischemic injury. Myocardial stunning is a transient, reversible dysfunction, while necrosis involves irreversible cell death. The relationship between IPC, stunning, and necrosis is not well understood, requiring further molecular investigation. This study aimed to investigate the proteomic changes associated with IPC, focusing on its relationship with myocardial stunning and necrosis. A novel 13.5-minute ischemia-reperfusion (I/R) rat model was specifically chosen to induce myocardial stunning, providing a unique approach to assess IPC effects in this context. Rats underwent either IPC with two 5-minute ischemia/reperfusion cycles followed by a 13.5-minute ischemic period or the procedure without IPC (no ischemic preconditioning, NIPC). Myocardial samples were collected at early (T1) and 4-hour post-reperfusion (T2) time points for proteomic analysis. Protein levels were quantified by differential labeling using TMTpro reagents, and subsequent liquid chromatography-mass spectrometry. IPC induced upregulation of proteins involved in endocytosis and Fc gamma R-mediated phagocytosis pathways at T1, while downregulating proteins related to tissue remodeling, immune response, and coagulation at T2. Conversely, NIPC exhibited upregulation of proteins associated with tissue damage and inflammation. IPC rats demonstrated enhanced leukocyte migration, complement activation, and immune response between T1 and T2. Consistent proteomic changes were observed between T1 and T2 in IPC vs. NIPC groups, and common alterations between IPC T2 vs. T1 and NIPC T2 vs. T1 comparisons underline shared pathways in cardiac complement and coagulation cascades. Our study reveals distinct proteomic changes induced by IPC in the context of myocardial stunning and necrosis. IPC activates early protective pathways, attenuates tissue damage and inflammation, and preserves myocardial function. These findings underscore IPC's reparative potential and identify myocardial stunning as an important, transient adaptation, which may have implications for supportive clinical management in I/R.

Exosomes derived from mesenchymal stem cells ameliorate impaired glucose metabolism in myocardial Ischemia/reperfusion injury through miR-132-3p/PTEN/AKT pathway

Exosomes secreted by mesenchymal stem cells (MSCs) have been considered as a novel biological therapy for myocardial ischemia/reperfusion injury (MIRI). However, the underlying mechanism of exosomes has not been completely established, especially in the early stage of MIRI. In this study, we primarily investigated the protective effect of exosomes on MIRI from both in vitro and ex vivo perspectives. Bioinformatic analysis was conducted to identify exosomal miRNA associated with myocardial protection, Genes and proteins related to functional studies and myocardial energy metabolism were analyzed and evaluated using techniques such as Polymerase Chain Re-action (PCR), Western blotting, double luciferase biochemical techniques, flow cytometry assay, etc. It was discovered that exosomes ameliorated cardiomyocyte injury t by delivery of miR-132-3p.This process reduced the expression of Phosphatase and tensin homolog (PTEN) mRNA and protein, enhanced the expression of phosphorylated protein kinase (pAKT), regulated the insulin signaling pathway, facilitated intracellular Glucose transporter 4 (GLUT4) protein membrane translocation, and enhanced glucose uptake and Adenosine Triphosphate (ATP) production. This study confirmed, for the first time, that MSC-EXO can provide myocardial protection in the early stages of MIRI through miR-132/PTEN/AKT pathway. This research establishes a theoretical and experimental foundation for the clinical application of MSC-derived exosomes.

IMproving Preclinical Assessment of Cardioprotective Therapies (IMPACT): a small animal acute myocardial infarction randomized-controlled multicenter study on the effect of ischemic preconditioning

Although many cardioprotective interventions have been shown to limit infarct size (IS), in preclinical animal studies of acute myocardial ischemia/reperfusion injury (IRI), their clinical translation to patient benefit has been largely disappointing. A major factor is the lack of rigor and reproducibility in the preclinical studies. To address this, we have established the IMproving Preclinical Assessment of Cardioprotective Therapies (IMPACT) small animal multisite acute myocardial infarction (AMI) network, with centralized randomization and blinded core laboratory IS analysis, and have validated the network using ischemic preconditioning (IPC). Eight sites from the COST Innovators Grant (IG16225) network participated in the IMPACT AMI study. Mice and rats were randomly allocated into Sham, Control, or IPC groups. The IRI group underwent 45 min (mice) or 30 min (rats) of left coronary artery occlusion followed by 24 h reperfusion. IPC comprised three cycles of 5 min occlusion/reperfusion before IRI. IS was determined by a blinded core lab. The majority of site showed significant cardioprotection with IPC. In pooled mouse data, IPC (N = 42) reduced IS/AAR by 35% compared to control (N = 48) (30 ± 16% versus 46 ± 13%; p < 0.005), and in rat data, IPC (N = 36) reduced IS/AAR by 29% when compared to control (N = 39) (32 ± 19% versus 45 ± 14%; p < 0.01). The IMPACT multisite mouse and rat AMI networks, with centralized randomization and blinded core IS analysis, were established to improve the reproducibility of cardioprotective interventions in preclinical studies and to facilitate the translation of these therapies for patient benefit.

Evolocumab attenuates myocardial ischemia/reperfusion injury by blocking PCSK9/LIAS-mediated cuproptosis of cardiomyocytes

Myocardial ischemia‒reperfusion (I/R) injury is the crucial cause of poor prognosis after revascularization in patients with myocardial infarction (MI) due to the lack of specific therapeutic drugs. Proprotein convertase subtilisin/Kexin type 9 (PCSK9) is related to the pathogenesis and progression of various cardiovascular diseases. However, the specific role of PCSK9 in I/R-induced cardiac injury remains to be further investigated. In this study, wild-type (WT) C57BL/6J mice were administered evolocumab (a monoclonal antibody of PCSK9) before I/R surgery. Cardiac damage and function were assessed by echocardiography and TTC/Evans Blue staining. Inflammation, oxidative stress, mitochondrial dysfunction, and cuproptosis were evaluated by histopathology and qPCR. The interaction between proteins was confirmed by protein docking and co-immunoprecipitation. Our data revealed that PCSK9 level was increased in I/R-induced mouse serum and hearts and in serum of MI patients. Furthermore, evolocumab significantly improved cardiac injury and dysfunction, inflammation, oxidative stress, and cuproptosis. Mechanistically, evolocumab obstructs the direct interaction of PCSK9 and LIAS, and subsequently inhibits cardiomyocyte cuproptosis. In conclusion, inhibition of PCSK9 alleviates I/R-induced cardiac remodeling and dysfunction by targeting LIAS-mediated cuproptosis, which may be a novel therapeutic strategy for patients with ischemic cardiomyopathy.

Necrosis-like cell death modes in heart failure: the influence of aetiology and the effects of RIP3 inhibition

Since cell dying in heart failure (HF) may vary based on the aetiology, we examined the main forms of regulated necrosis, such as necroptosis and pyroptosis, in the hearts damaged due to myocardial infarction (MI) or pressure overload. We also investigated the effects of a drug inhibiting RIP3, a proposed convergent point for both these necrosis-like cell death modes. In rat hearts, left ventricular function, remodelling, pro-cell death, and pro-inflammatory events were investigated, and the pharmacodynamic action of RIP3 inhibitor (GSK'872) was assessed. Regardless of the HF aetiology, the heart cells were dying due to necroptosis, albeit the upstream signals may be different. Pyroptosis was observed only in post-MI HF. The dysregulated miRNAs in post-MI hearts were accompanied by higher levels of a predicted target, HMGB1, its receptors (TLRs), as well as the exacerbation of inflammation likely originating from macrophages. The RIP3 inhibitor suppressed necroptosis, unlike pyroptosis, normalised the dysregulated miRNAs and tended to decrease collagen content and affect macrophage infiltration without affecting cardiac function or structure. The drug also mitigated the local heart inflammation and normalised the higher circulating HMGB1 in rats with post-MI HF. Elevated serum levels of HMGB1 were also detected in HF patients and positively correlated with C-reactive protein, highlighting pro-inflammatory axis. In conclusion, in MI-, but not pressure overload-induced HF, both necroptosis and pyroptosis operate and might underlie HF pathogenesis. The RIP3-targeting pharmacological intervention might protect the heart by preventing pro-death and pro-inflammatory mechanisms, however, additional strategies targeting multiple pro-death pathways may exhibit greater cardioprotection.

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

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

Inter-organ communication: pathways and targets to cardioprotection and neuro-protection. A report from the 12th Hatter Cardiovascular Institute workshop

A long-standing aim in the setting of various pathologies including acute myocardial infarction, chronic kidney disease (CKD), and ischaemic stroke, has been to identify successful approaches to augment cellular and organ protection. Although the continual evolution and refinement of ideas over the past few decades has allowed the field to progress, we are yet to realise successful clinical translation of this concept. The 12th Hatter Cardiovascular Workshop identified a number of important points and key questions for future research relating to cardio- and neuro-protection and interorgan communication. Specific topics that were discussed include the 'cardio-metabolic-renal' axis of organ protection, the parasympathetic signalling hypothesis, the role of the coronary microvasculature in myocardial infarction, the RISK pathway of cardioprotection, extracellular vesicles and the way forward, the future for clinical studies of remote ischaemic conditioning, and new experimental models for cardio-oncology investigations.

Transcoronary cooling and dilution for cardioprotection during revascularisation for ST-segment elevation myocardial infarction: Design and rationale of the STEMI-Cool study

BACKGROUND

ST-segment elevation myocardial infarction (STEMI) is treated with immediate primary percutaneous coronary intervention (pPCI) to restore coronary blood flow in the acutely ischaemic territory, but is associated with reperfusion injury limiting the benefit of the therapy. No treatment has proven effective in reducing reperfusion injury. Transcoronary hypothermia has been tested in clinical studies and is well tolerated, but is generally established after crossing the occlusion with a guidewire therefore after initial reperfusion, which might have contributed to the neutral outcomes. Transcatheter strategies may also offer additional benefit through haemodilution and the resultant controlled reperfusion, but this has not been fully investigated for pPCI.

DESIGN

STEMI-Cool is a pragmatic, registry-based randomised clinical pilot trial to test the recruitment rate, feasibility, and safety of a simple transcoronary cooling and dilution protocol. Sixty STEMI patients undergoing pPCI will be randomised 1:1 to standard of care or continuous infusion of room temperature saline through the guiding catheter to achieve intracoronary temperature reductions of 6 to 8°C, commencing before crossing the coronary occlusion with a guidewire. Mechanistic outcome measures will include microvascular resistance, biomarkers of inflammation before infusion and at 24 hour, and magnetic resonance imaging of myocardial salvage and infarct size.

CONCLUSIONS

STEMI-Cool will investigate the recruitment rate, feasibility and safety of an innovative and simple cooling and diluting strategy for cardioprotection before and during reperfusion with pPCI, aiming to address limitations faced in other studies. Mechanistic outcome measures will allow insight into inflammatory, microvascular and structural changes induced by transcoronary cooling and dilution.

Baicalin and baicalein against myocardial ischemia-reperfusion injury: A review of the current documents

Myocardial ischemia-reperfusion injury (MIRI) is a significant challenge in the treatment of ischemic heart disease (IHD), arising as a complication from reperfusion therapies designed to restore blood flow after an ischemic event. Despite the availability of various therapeutic strategies, finding an effective treatment for MIRI remains difficult. Baicalin and its aglycone form (baicalein), natural compounds derived from the Chinese skullcap plant (Scutellaria baicalensis), have shown promise due to their antioxidant, anti-inflammatory, and cardioprotective properties. This review aims to explore the potential of baicalin and baicalein as treatments for MIRI, with a focus on their molecular and cellular level effects. These natural agents can decrease oxidative stress by promoting antioxidant enzymes and decreasing harmful oxidative substances that damage cardiac cells. They also exert anti-inflammatory effects by blocking specific pathways that trigger the release of inflammatory mediators. Additionally, they also improve heart cell survival, infarct region, and overall cardiac function by inhibiting key signaling pathways involved in cell death. Research in both animal and cell models suggests that these flavonoids, especially baicalin, can restore cardiac health following MIRI, improving cardiac performance, and reducing cardiac damage. These findings underscore the potential of baicalin and baicalein as therapeutic options for MIRI. However, further research and clinical trials are necessary to elucidate their mechanisms fully and to develop baicalin into a viable treatment.

Mitochondrial transplantation combined with mitoquinone and melatonin: A survival strategy against myocardial reperfusion injury in aged rats

Myocardial ischaemia-reperfusion (IR) injury poses a severe threat to cardiac health, particularly in the ageing population, where susceptibility to such damage is significantly heightened owing to age-related declines in mitochondrial function, thus highlighting mitochondria as crucial targets for innovative therapies. The aim of this study was to investigate the combined modality therapy involving mitochondrial transplantation and the mitochondrial boosters mitoquinone and melatonin to address myocardial IR injury in aged rats. A total of 54 male Wistar rats, aged 22-24 months, were randomly divided into groups that either received IR injury or not, and were subjected to various treatments, both individually and in combination. Myocardial IR injury was induced by temporarily blocking and reopening the left anterior descending coronary artery. Mitoquinone was given intraperitoneally for 14 days prior to ischaemia, while melatonin and isolated mitochondria were administered intraperitoneally and intramyocardially, respectively, at the onset of reperfusion. Finally, we evaluated changes in haemodynamic indices, creatine kinase-MB levels, mitochondrial function endpoints and the expression of mitochondrial biogenesis genes, including sirtuin 1 (SIRT-1), peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) and nuclear respiratory factor 2 (NRF-2). The triple therapy enhanced myocardial function, decreased creatine kinase-MB levels and improved mitochondrial function along with the expression of mitochondrial biogenesis genes in aged IR rats. This combined approach elicited significant cardioprotection in comparison to single or dual therapies. The triple therapy provided substantial cardioprotection in aged rat hearts by improving mitochondrial function and biogenesis through enhanced SIRT-1/PGC-1α/NRF-2 profiles, suggesting a promising strategy for mitigating IR injury in elderly patients.

Enhancing microcirculation in STEMI patients: can intracoronary thrombolysis combined with thrombus aspiration provide an optimal strategy?

ST-elevation myocardial infarction (STEMI) is a critical cardiovascular emergency characterized by acute coronary artery occlusion and subsequent myocardial injury. The current standard of care is primary percutaneous coronary intervention (PPCI), which aims to rapidly restore epicardial blood flow. However, despite successful revascularization, microvascular obstruction (MVO) remains a major challenge, contributing to adverse clinical outcomes. This article explores the potential role of intracoronary thrombolysis, in conjunction with thrombus aspiration, in improving microcirculatory perfusion during PCI for STEMI patients. The pathophysiology of MVO is systematically reviewed, followed by an evaluation of clinical studies on thrombus aspiration and intracoronary thrombolysis in STEMI management. Furthermore, the potential benefits of combining these two approaches in mitigating MVO are discussed. Finally, the clinical evidence is critically assessed, existing controversies are analyzed, and directions for future research are proposed.

Necroptosis in myocardial ischaemia-reperfusion injury: current update on mechanisms, therapeutic targets, and translational potential

Necroptosis is a programmed form of cell death that has gained significant attention in the field of cardiovascular research due to its involvement in myocardial infarction (MI) and myocardial ischaemia-reperfusion (I/R) injury. Unlike apoptosis, necroptosis elicits a pro-inflammatory response, contributing to myocardial injury, fibrosis, and adverse remodelling. This review aims to provide an overview of the molecular mechanisms underlying necroptosis, with a particular focus on its role in myocardial I/R injury. Key regulatory proteins such as Receptor-interacting protein kinase 3 (RIPK3) and Mixed lineage kinase domain-like protein (MLKL) are central to the necroptotic process, mediating cell death and inflammation. The review discusses the potential of targeting necroptosis as a therapeutic strategy for managing cardiovascular diseases, particularly post-MI. The RIPK3-CaMKII-mitochondrial permeability transition pore (mPTP) pathway is identified as a critical signalling axis in necroptosis and its inhibition may offer protective benefits in myocardial injury. The review also considers the role of natural and chemical inhibitors and other genes in necroptosis regulation. Overall, targeting necroptosis represents a promising avenue for therapeutic intervention to mitigate cardiac injury, promote recovery, and improve long-term patient outcomes in cardiovascular diseases.

Attenuation of cardiac ischemia/reperfusion injury via the decoy receptor DcR2 by targeting the PLAD domain of the death receptor DR5

Myocardial cell death caused by ischemia and hypoxia is the main cause of myocardial injury. DcR2 is the decoy receptor of TRAIL, and the role of DcR2 in myocardial ischemia/reperfusion (I/R) injury is largely unknown. Recent studies have shown that DcR2 not only binds to TRAIL as a receptor but also acts as a ligand for DR5 to block TRAIL-induced apoptosis in vitro, but the preference of DcR2 for binding to TRAIL or DR5 in vivo remains unknown. Our study revealed that the hDcR2-Fc fusion protein plays a cardioprotective role in a mouse model of myocardial I/R injury by reducing apoptosis. An affinity assay revealed that DcR2 has a greater affinity for DR5 than for TRAIL and that DcR2 is more inclined to bind to DR5. Mechanistic studies elucidated that deletion of PLAD eliminated the protective effect of hDcR2-Fc on heart injury caused by I/R. DcR2 forms a heterocomplex with DR5 through a similar PLAD domain. Taken together, this study revealed that DcR2 can ameliorate myocardial I/R injury by targeting DR5 to form a heterocomplex through the PLAD domain, blocking apoptosis, thus providing a new preventive strategy for the treatment of myocardial I/R injury.

Endophilin B1 is essential for maintaining cardiac function by regulating mitocytosis

Endophilin B1 is a member of the Endophilin family and has been shown to be involved in apoptosis, mitochondrial morphological changes and autophagy. Although Endophilin B1 is highly expressed in the heart, its role in the maintenance of normal cardiac function and myocardial ischemia and reperfusion (I/R) injury remains unclear. Here, we found that Endophilin B1 deletion provoked spontaneous cardiac contractile dysfunction, cardiac hypertrophy and fibrosis at 16 weeks of age. Moreover, at 8 weeks of age, although spontaneous cardiac dysfunction in Endophilin B1 deletion mice had not developed, the deletion of Endophilin B1 exacerbated I/R-induced cardiac contractile dysfunction and cardiomyocyte death, whereas restoration of Endophilin B1 expression in the heart reduced I/R injury. Furthermore, we discovered that Endophilin B1 is indispensable for maintaining normal mitochondrial structure and function. In addition, we found that Endophilin B1 is localized in extracellular mitochondrion-containing vesicles and is required for mitocytosis, a process by which damaged mitochondria are disposed through extracellular vesicles. In conclusion, our study identified Endophilin B1 as an essential mitocytosis regulator for maintaining mitochondrial homeostasis and cardiac function. These findings suggest that Endophilin B1 is a novel therapeutic target for cardiac disorders such as I/R injury, myocardial infarction and heart failure.

Novel paper sensor with modified aptamer for accurate detection of clinical cardiac troponin I

Accurate and rapid detection of Cardiac Troponin I (CTnI) is essential for the early diagnosis and timely management of myocardial infarction (MI). However, conventional detection methods relying on antigen-antibody interactions often face challenges such as high costs and lengthy procedures. Novel detection methods based on antigen-aptamer interactions offer a potentially superior alternative. Nevertheless, the performance of antigen-aptamer sensors is typically compromised by the unstable structure of aptamers, resulting in limited sensitivity and inconsistent specificity in CTnI detection. To address these issues, we have developed an innovative aptamer structure to construct a paper-based sensor comprising a paper electrode and a CTnI aptamer detection module. The paper electrode employs PEDOT:PSS to uniformly distribute single-walled carbon nanotubes (SWCNTs) at high concentrations on filter paper. The detection module utilizes modified CTnI aptamers with a continuous (AT)5 sequence in the anchor domain to enhance stable immobilization on SWCNTs without chemical reactions. We discovered that incorporating appropriate 18-atom hexa-ethylene glycol spacers (Sp18) between the protein-capture and anchor domains of the aptamers can improve the sensitivity of the current response for CTnI detection. Through the optimization of annealing temperature and duration, the paper sensor Aps3-CTnI-PS@CP, which integrates (AT)5 and three Sp18 into the aptamer, demonstrated enhanced sensitivity and specificity for CTnI detection. When applied to clinical samples, Aps3-CTnI-PS@CP exhibited a favorable receiver operating characteristic (ROC) curve, with an area under the curve (AUC) of 0.982, a sensitivity of 0.917, and a specificity of 0.945 for CTnI detection. This performance correlates strongly with traditional chemiluminescence immunoassay (CLIA) assays used in clinical settings. The straightforward fabrication process and minimal batch-to-batch variability make Aps3-CTnI-PS@CP a promising candidate for clinical aptamer-based CTnI detection.

Semaglutide attenuates myocardial ischemia-reperfusion injury by inhibiting ferroptosis of cardiomyocytes via activation of PKC-S100A9 axis

Objective

The incidence of ischemic cardiomyopathy increases annually worldwide, and it is the leading cause of mortality in China. Although interventional diagnostic and therapeutic techniques can promptly open the culprit vessels, myocardial ischemia-reperfusion injury (MIRI), resulting from restored blood flow, is often inevitable. Semaglutide (Sem), a novel GLP-1 analogue, is primarily utilized in managing Type 2 diabetes mellitus (T2DM). Recent research indicates that semaglutide may reduce the risk of major adverse cardiovascular events. Therefore, the purpose of this study is to explore whether semaglutide can ameliorate MIRI and explore its potential mechanism.

Methods and results

: A mouse model of myocardial ischemia-reperfusion (I/R) was created by ligating the left anterior descending coronary artery (LAD) first for 45 min and then reperfusing the heart for 24 h. Assessment of cardiac function and fibrosis were conducted through small animal ultrasound and Masson's staining. It was observed that semaglutide enhanced cardiac function recovery and diminished fibrosis in the I/R model. In vivo experiments, semaglutide proved to mitigate oxidative stress and inhibit ferroptosis in cardiomyocytes. RNA sequencing showed that S100 calcium binding protein A9 (S100A9) was the target gene of semaglutide to protect against MIRI. In vitro, experiments showed that semaglutide decreased the expression of S100A9 by activating the Protein Kinase C(PKC) pathway, thus inhibiting ferroptosis in cardiomyocytes.

Conclusion

Semaglutide can reduce I/R-induced myocardial injury by inhibiting the ferroptosis of cardiomyocytes. In the mechanism, semaglutide mainly reduce the expression of S100A9 via the activation of PKC signaling pathway. Therefore, semaglutide is considered as a potential treatment option for MIRI.

Electroacupuncture Preconditioning Attenuates Myocardial Ischemia-Reperfusion Injury in Rats Partially Through Nrf2-Mediated Reduction of Oxidative Stress and Pyroptosis

Oxidative stress and pyroptosis have been established as key contributors to myocardial ischemia-reperfusion injury (MIRI). While previous studies reported that electroacupuncture (EA) preconditioning exerted cardioprotective effects, the underlying mechanisms remain elusive. Thus, this study aimed to investigate the effects of EA preconditioning on oxidative stress and pyroptosis in MIRI rats, and explore the role of nuclear factor E2-associated factor 2 (Nrf2) throughout that process. A MIRI model was constructed by ligating the left anterior descending coronary artery for 30 min, followed by 4 h of reperfusion in rats. Prior to modeling, rats were subjected to EA at the Neiguan Point for three days. Furthermore, ML385, a Nrf2 inhibitor, was administered in order to examine the role of Nrf2 in regulating oxidative stress and pyroptosis following EA preconditioning. The results revealed that EA preconditioning improved left ventricular function after MIRI and reduced both the myocardial infarction area and cTnT levels. Meanwhile, EA preconditioning alleviated MIRI-induced oxidative stress and pyroptosis, as evidenced by the downregulation of ROS, MDA, NF-κB p65, caspase-1, IL-1β, and GSDMD-N, and the upregulation of SOD and HO-1. Mechanistically, EA up-regulated enhanced the expression of Nrf2. However, its cardioprotective effects and ability to attenuate oxidative stress and pyroptosis were suppressed by the inhibition of Nrf2. Taken together, our study indicated that EA preconditioning attenuated MIRI in rats by mitigating oxidative stress and pyroptosis, with Nrf2 playing a vital role in this protective mechanism.

Mitochondrial quality control in cardiomyocytes: safeguarding the heart against disease and ageing

Mitochondria are multifunctional organelles that are important for many different cellular processes, including energy production and biosynthesis of fatty acids, haem and iron-sulfur clusters. Mitochondrial dysfunction leads to a disruption in these processes, the generation of excessive reactive oxygen species, and the activation of inflammatory and cell death pathways. The consequences of mitochondrial dysfunction are particularly harmful in energy-demanding organs such as the heart. Loss of terminally differentiated cardiomyocytes leads to cardiac remodelling and a reduced ability to sustain contraction. Therefore, cardiomyocytes rely on multilayered mitochondrial quality control mechanisms to maintain a healthy population of mitochondria. Mitochondrial chaperones protect against protein misfolding and aggregation, and resident proteases eliminate damaged proteins through proteolysis. Irreparably damaged mitochondria can also be degraded through mitochondrial autophagy (mitophagy) or ejected from cells inside vesicles. The accumulation of dysfunctional mitochondria in cardiomyocytes is a hallmark of ageing and cardiovascular disease. This accumulation is driven by impaired mitochondrial quality control mechanisms and contributes to the development of heart failure. Therefore, there is a strong interest in developing therapies that directly target mitochondrial quality control in cardiomyocytes. In this Review, we discuss the current knowledge of the mechanisms involved in regulating mitochondrial quality in cardiomyocytes, how these pathways are altered with age and in disease, and the therapeutic potential of targeting mitochondrial quality control pathways in cardiovascular disease.

Macrophage and cardiomyocyte roles in cardioprotection: Exploiting the NLRP3 Inflammasome inhibitor INF150

BACKGROUND

Cardiovascular diseases remain the leading cause of disability and death in the Western world. Effective cardioprotection involves limiting ischemia/reperfusion injury (IRI), including cell death (pyroptosis) driven by the NLRP3 inflammasome. While various cardiac resident cellular populations contribute to cardioprotection, it remains unclear whether targeting resident macrophages is inherently cardioprotective. Given that INF150, an NLRP3 inhibitor, exhibits varying abilities to penetrate cardiomyocytes and macrophages, we sought to address this question.

METHODS

We studied the cardioprotective potential of INF150, the potent metabolite of the NLRP3 inhibitor INF195, in isolated hearts or cells. In isolated hearts, we measured infarct size, caspase-1 cleavage, and interleukins (IL) release, while in macrophages, naïve H9c2 and differentiated H9c2 cells, we analyzed cell viability, and pyroptosis markers, including IL-1β release and Gasdermin D cleavage, following hypoxia/reoxygenation (H/R).

RESULTS AND CONCLUSION

While INF150 effectively shielded macrophages from LPS/ATP challenges, it failed to penetrate H9c2 and differentiated H9c2, even at high concentrations (no changes in pyroptosis markers induced by H/R). In the isolated mice heart model, INF150 did not demonstrate cardioprotective effects: infarct size, IL-1β, cleaved caspase-1 levels did not change significantly across tested concentrations of INF150. These findings suggest that while INF150 shows promise in macrophage/phagocytic models, its inability to penetrate cardiomyocytes limits its effectiveness in the whole cardiac tissue. Our results underscore the importance of cardiomyocyte uptake for effective cardioprotection, highlighting the need for NLRP3 inhibitors capable of targeting these cells directly. Future research should focus on enhancing the delivery and cardiomyocyte uptake of NLRP3 inhibitors to achieve cardioprotection. Unlike its precursor, INF195, which penetrates H9c2 cells, INF150 does not appear to offer cardioprotection in the whole organ.

MiR-222-3p loaded stem cell nanovesicles repair myocardial ischemia damage via inhibiting mitochondrial oxidative stress

AIMS

Mitochondrial oxidative stress (MOS) is a key contributor to poor cardiac function and a major driver of myocardial ischemia-reperfusion injury (MIRI). Our previous research demonstrated that stem cell-derived nanovesicles (NVs) enhanced cardiac function following ischemia-reperfusion (I/R) injury, although the underlying mechanisms remain unclear. We constructed and characterized miR-222-3p-loaded NVs.

MATERIALS AND METHODS

An in vitro hypoxia-reoxygenation (H/R) model was established using H9C2 cardiomyocytes. Mitochondrial oxidative respiratory function was assessed using Seahorse XF technology, while mitochondrial reactive oxygen species (mtROS) levels were quantified via flow cytometry. Additional assessments included mitochondrial permeability transition pore (mPTP) status, mitochondrial membrane potential, and mitochondrial DNA (mtDNA) integrity. An in vivo H/R model was developed using C57BL/6 mice. The therapeutic effects of NVs on MOS reduction and cardiac function improvement were evaluated through Masson's staining, immunofluorescence, echocardiography, transmission electron microscopy (TEM), and positron emission tomography/computed tomography (PET/CT).

KEY FINDINGS

RNA immunoprecipitation (RIP) confirmed that miR-222-3p directly targets cyp1a1. Overexpression of miR-222-3p or knockdown of cyp1a1 significantly improved mitochondrial activity in cardiomyocytes and conferred protection against I/R injury. Conversely, overexpression of cyp1a1 abrogated the protective effects of miR-222-3p. In vivo, NV treatment enhanced cardiac function, reduced MOS, and improved mitochondrial respiratory capacity in MIRI model mice. NV treatment, via miR-222-3p-mediated suppression of cyp1a1, mitigates MOS, enhances mitochondrial respiratory function, and improves cardiac outcomes in MIRI models.

SIGNIFICANCE

These findings provide a foundational basis for the clinical translation of NV-based therapies.

Lactylation: a promising therapeutic target in ischemia-reperfusion injury management

Ischemia-reperfusion injury (IRI) is a critical condition that poses a significant threat to patient safety. The production of lactate increases during the process of IRI, and lactate serves as a crucial indicator for assessing the severity of such injury. Lactylation, a newly discovered post-translational modification in 2019, is induced by lactic acid and predominantly occurs on lysine residues of histone or nonhistone proteins. Extensive studies have demonstrated the pivotal role of lactylation in the pathogenesis and progression of various diseases, including melanoma, myocardial infarction, hepatocellular carcinoma, Alzheimer's disease, and nonalcoholic fatty liver disease. Additionally, a marked correlation between lactylation and inflammation has been observed. This article provides a comprehensive review of the mechanism underlying lactylation in IRI to establish a theoretical foundation for better understanding the interplay between lactylation and IRI.

Diselenide Nanogels Modulate Mitochondrial Function and Mitigate Oxidative Stress in Cardiomyocytes for Enhanced Cardiac Repair

Mitochondrial dysfunction and oxidative stress are pivotal factors contributing to the loss of cardiac function following heart injury, yet these aspects are frequently underappreciated in the medication design paradigm. Here we have developed diselenide-cross-linked zwitterionic nanogels to restore mitochondrial homeostasis and boost energy supply for damaged heart repair. These nanogels exhibit an enhanced circulation time within the bloodstream post systemic administration and have been observed to concentrate at the site of the damaged myocardium in both myocardial infarct (MI) rat model and cardiotoxic mouse model. Our mechanistic investigations have revealed that these nanogels have the capacity to mitigate the oxidative microenvironment, thereby preserving the mitochondrial function of cardiomyocytes. Moreover, the degradation products of these nanogels have been shown to upregulate intracellular ATP synthesis, which in turn increases cardiac contractility and promotes the recovery of cardiac function. The innovative nanogel system presented herein holds significant potential for clinical translation, offering a therapeutic strategy for the restoration of cardiac function and a fresh perspective on maintaining energy metabolism homeostasis in the treatment of heart injury.

Intramyocardial Hemorrhage in Patients with Acute Myocardial Infarction Without Reperfusion Therapy: A Prospective Study

Background and Aims

IMH commonly presents in STEMI patients receiving reperfusion therapy and is considered as an ischemic reperfusion injury. However, it is unclear whether IMH occurs in AMI patients without reperfusion therapy.

Methods and Results

We prospectively enrolled 40 patients with STEMI and 41 patients with NSTEMI admitted to the CCU of the Second Xiangya Hospital of Central South University from April 2020 to November 2021, all of whom did not receive reperfusion therapy. In the STEMI group, 16 patients were detected with IMH by CMR. However, in the NSTEMI group, only 3 patients were detected. The incidence of IMH was significantly higher in patients with STEMI than NSTEMI (16/40 vs 3/41, P < 0.001). Among patients with STEMI, the incidence of IMH was not significantly different between patients who underwent primary percutaneous coronary intervention and those who did not (16/40 vs 27/65, P = 0.876). Patients in the spontaneous reperfusion group had a higher incidence of IMH than patients in the non-spontaneous reperfusion group (11/23 vs 5/17, P = 0.240). Similarly, in patients with STEMI who did not receive reperfusion therapy, the incidence of MACE was higher in the IMH-present group than in the IMH-absent group (5/16 vs 2/24, P = 0.063).

Conclusion

The incidence of IMH is comparable in patients with STEMI with or without reperfusion therapy, but considerably higher than that in NSTEMI patients. Patients with STEMI can present with IMH even when infarct-related vessel flow is not restored.

ROS-differentiated release of Apelin-13 from hydrogel comprehensively treats myocardial ischemia-reperfusion injury

Treatment of myocardial ischemia-reperfusion (MI/R) injury still faces the lack of clinically approved drugs. Apelin-13 is a highly promising drug candidate of MI/R injury, but hampered by its extremely short half-life in plasma. This calls for efficient and smart delivering system for Apelin-13 delivery, but has not been reported. Herein, a reactive oxygen species (ROS)-responsive hydrogelator YFF-TK-FFY is designed, which co-assembles with Apelin-13 to form the peptide hydrogel Apelin-13@Gel TK. This hydrogel responds to ROS at varying levels in the surrounding environment of MI/R and releases Apelin-13 at different rates. In an MI/R injury mouse model, Apelin-13@Gel TK rapidly releases Apelin-13 in response to the high ROS in the core area of MI/R injury, efficiently reducing cardiomyocyte apoptosis within three days. In the ROS-low border zone, Apelin-13@Gel TK provides a slow and sustained release of Apelin-13, promoting angiogenesis and lymphatic remodeling, and facilitating the resolution of inflammation in the later repair stage after MI/R injury. By offering a spatiotemporally controlled drug release in response to ROS gradients in the MI/R microenvironment, this smart hydrogel presents a promising therapeutic strategy for effective treatment of MI/R injury.

Low-Frequency Electrical Stimulation of the Auricular Branch of the Vagus Nerve in Patients with ST-Elevation Myocardial Infarction: A Randomized Clinical Trial

Background: Despite the vast evidence of the beneficial effect of vagus nerve stimulation on the course of myocardial infarction confirmed in studies using animal models, the introduction of this method into actual clinical practice remains uncommon. Objective: The objective of our study was to evaluate the effect of transcutaneous vagus nerve stimulation (tVNS) on in-hospital and long-term outcomes for patients with ST-elevation myocardial infarction. Materials and Methods: A blind, randomized, placebo-controlled clinical trial was conducted. The participants were randomly split into two groups. The Active tVNS group was subjected to stimulation of the tragus containing the auricular branch of the vagus nerve. The Sham tVNS group underwent stimulation of the lobule. Stimulation was performed immediately on admission before the start of the percutaneous coronary intervention (PCI). Then, tVNS continued throughout the entire PCI procedure and 30 min after its completion. The primary endpoints were hospital mortality and 12-month mortality. The secondary endpoints were in-hospital and remote non-lethal cardiovascular events. The combined endpoint consisted of major adverse cardiovascular events (MACEs)-recurrent myocardial infarction, stroke/TIA, and overall mortality. Results: A total of 110 patients were randomized into the Active tVNS group (n = 55) and the Sham tVNS group (n = 55). The incidences of hospital mortality, cardiogenic shock, and AV block 3 were statistically less common in the Active tVNS group than in the Sham tVNS group (p = 0.024*, p = 0.044*, and p = 0.013*, respectively). In the long-term period, no statistical differences were found in the studied outcomes obtained following the construction of Kaplan-Meyer survival curves. When comparing groups by total mortality, taking into account hospital mortality, we observed a tendency for the survival curves to diverge (Logrank test, p = 0.066). Statistical significance was revealed by the composite endpoint, taking into account hospital events (Logrank test, p = 0.0016*). Conclusions: tVNS significantly reduced hospital mortality (p = 0.024*), the level of markers of myocardial damage, and the frequency of severe cardiac arrhythmias in patients with acute myocardial infarction. In the long term, the prognostic value of tVNS was revealed by the composite endpoint major adverse cardiovascular events. Further studies with an expanded sample are needed for a more detailed verification of the data obtained to confirm the effectiveness of tVNS and allow an in-depth analysis of the safety and feasibility of its use in routine clinical practice. This clinical trial is registered with ClinicalTrials database under a unique identifier: NCT05992259.

Different types of cell death and their interactions in myocardial ischemia-reperfusion injury

Myocardial ischemia-reperfusion (I/R) injury is a multifaceted process observed in patients with coronary artery disease when blood flow is restored to the heart tissue following ischemia-induced damage. Cardiomyocyte cell death, particularly through apoptosis, necroptosis, autophagy, pyroptosis, and ferroptosis, is pivotal in myocardial I/R injury. Preventing cell death during the process of I/R is vital for improving ischemic cardiomyopathy. These multiple forms of cell death can occur simultaneously, interact with each other, and contribute to the complexity of myocardial I/R injury. In this review, we aim to provide a comprehensive summary of the key molecular mechanisms and regulatory patterns involved in these five types of cell death in myocardial I/R injury. We will also discuss the crosstalk and intricate interactions among these mechanisms, highlighting the interplay between different types of cell death. Furthermore, we will explore specific molecules or targets that participate in different cell death pathways and elucidate their mechanisms of action. It is important to note that manipulating the molecules or targets involved in distinct cell death processes may have a significant impact on reducing myocardial I/R injury. By enhancing researchers' understanding of the mechanisms and interactions among different types of cell death in myocardial I/R injury, this review aims to pave the way for the development of novel interventions for cardio-protection in patients affected by myocardial I/R injury.

The Multifaceted Roles of BACH1 in Disease: Implications for Biological Functions and Therapeutic Applications

BTB domain and CNC homolog 1 (BACH1) belongs to the family of basic leucine zipper proteins and is expressed in most mammalian tissues. It can regulate its own expression and play a role in transcriptionally activating or inhibiting downstream target genes. It has a crucial role in various biological processes, such as oxidative stress, cell cycle, heme homeostasis, and immune regulation. Recent research highlights BACH1's significant regulatory roles in a series of conditions, including stem cell pluripotency maintenance and differentiation, growth, senescence, and apoptosis. BACH1 is closely associated with cardiovascular diseases and contributes to angiogenesis, atherosclerosis, restenosis, pathological cardiac hypertrophy, myocardial infarction, and ischemia/reperfusion (I/R) injury. BACH1 promotes tumor cell proliferation and metastasis by altering tumor metabolism and the epithelial-mesenchymal transition phenotype. Moreover, BACH1 appears to show an adverse role in diseases such as neurodegenerative diseases, gastrointestinal disorders, leukemia, pulmonary fibrosis, and skin diseases. Inhibiting BACH1 may be beneficial for treating these diseases. This review summarizes the role of BACH1 and its regulatory mechanism in different cell types and diseases, proposing that precise targeted intervention of BACH1 may provide new strategies for human disease prevention and treatment.