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Clinical and Experimental Hypertension... Dec 2023Acute myocardial infarction (AMI) is the leading cause of death worldwide. Ischemia-reperfusion (I/R) injury is considered the most common contributor to AMI. Hirsutine...
Acute myocardial infarction (AMI) is the leading cause of death worldwide. Ischemia-reperfusion (I/R) injury is considered the most common contributor to AMI. Hirsutine has been shown to protect cardiomyocytes against hypoxic injury. The present study investigated whether hirsutine improved AMI induced by I/R injury and the underlying mechanisms. In our study, we used a rat model of myocardial I/R injury. The rats were given hirsutine daily (5, 10, 20 mg/kg) by gavage for 15 days before the myocardial I/R injury. Detectable changes were observed in myocardial infarct size, mitochondrial function, histological damage, and cardiac cell apoptosis. According to our findings, hirsutine pre-treatment reduced the myocardial infarct size, enhanced cardiac function, inhibited cell apoptosis, reduced the tissue lactate dehydrogenase (LDH) and reactive oxygen species (ROS) content, as well as enhanced myocardial ATP content and mitochondrial complex activity. In addition, hirsutine balanced mitochondrial dynamics by increasing Mitofusin2 (Mfn2) expression while decreasing dynamin-related protein 1 phosphorylation (p-Drp1), which was partially regulated by ROS and calmodulin-dependent protein kinase II phosphorylation (p-CaMKII). Mechanistically, hirsutine inhibited mitochondrial-mediated apoptosis during I/R injury by blocking the AKT/ASK-1/p38 MAPK pathway. This present study provides a promising therapeutic intervention for myocardial I/R injury.
Topics: Rats; Animals; Calcium-Calmodulin-Dependent Protein Kinase Type 2; Reactive Oxygen Species; Myocardial Reperfusion Injury; Mitochondria; Myocytes, Cardiac; Myocardial Infarction; Apoptosis
PubMed: 36951068
DOI: 10.1080/10641963.2023.2192444 -
Advanced Science (Weinheim,... Sep 2023Cardiovascular disease is the leading cause of death worldwide. Reperfusion therapy is vital to patient survival after a heart attack but can cause myocardial...
Cardiovascular disease is the leading cause of death worldwide. Reperfusion therapy is vital to patient survival after a heart attack but can cause myocardial ischemia/reperfusion injury (MI/RI). Nitric oxide (NO) can ameliorate MI/RI and is a key molecule for drug development. However, reactive oxygen species (ROS) can easily oxidize NO to peroxynitrite, which causes secondary cardiomyocyte damage. Herein, L-arginine-loaded selenium-coated gold nanocages (AAS) are designed, synthesized, and modified with PCM (WLSEAGPVVTVRALRGTGSW) to obtain AASP, which targets cardiomyocytes, exhibits increased cellular uptake, and improves photoacoustic imaging in vitro and in vivo. AASP significantly inhibits oxygen glucose deprivation/reoxygenation (OGD/R)-induced H9C2 cell cytotoxicity and apoptosis. Mechanistic investigation revealed that AASP improves mitochondrial membrane potential (MMP), restores ATP synthase activity, blocks ROS generation, and prevents NO oxidation, and NO blocks ROS release by regulating the closing of the mitochondrial permeability transition pore (mPTP). AASP administration in vivo improves myocardial function, inhibits myocardial apoptosis and fibrosis, and ultimately attenuates MI/RI in rats by maintaining mitochondrial function and regulating NO signaling. AASP shows good safety and biocompatibility in vivo. This findings confirm the rational design of AASP, which can provide effective treatment for MI/RI.
Topics: Rats; Animals; Myocardial Reperfusion Injury; Nitric Oxide; Reactive Oxygen Species; Gold; Arginine; Mitochondria
PubMed: 37449329
DOI: 10.1002/advs.202302123 -
Free Radical Biology & Medicine Aug 2023Myocardial ischemia/reperfusion (I/R) injury is characterized by cell death via various cellular mechanisms upon reperfusion. As a new type of cell death, ferroptosis...
RATIONALE
Myocardial ischemia/reperfusion (I/R) injury is characterized by cell death via various cellular mechanisms upon reperfusion. As a new type of cell death, ferroptosis provides new opportunities to reduce myocardial cell death. Ferroptosis is known to be more active during reperfusion than ischemia. However, the mechanisms regulating ferroptosis during ischemia and reperfusion remain largely unknown.
METHODS
The contribution of ferroptosis in ischemic and reperfused myocardium were detected by administered of Fer-1, a ferroptosis inhibitor to C57BL/6 mice, followed by left anterior descending (LAD) ligation surgery. Ferroptosis was evaluated by measurement of cell viability, ptgs2 mRNA level, iron production, malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) levels. H9C2 cells were exposed to hypoxia/reoxygenation to mimic in vivo I/R. We used LC-MS/MS to identify potential E3 ligases that interacted with frataxin in heart tissue. Cardiac-specific overexpression of frataxin in whole heart was achieved by intracardiac injection of frataxin, carried by adeno-associated virus serotype 9 (AAV9) containing cardiac troponin T (cTnT) promoter.
RESULTS
We showed that regulators of iron metabolism, especially iron regulatory protein activity, were increased in the ischemic myocardium or hypoxia cardiomyocytes. In addition, we found that frataxin, which is involved in iron metabolism, is differentially expressed in the ischemic and reperfused myocardium and involved in the regulation of cardiomyocytes ferroptosis. Furthermore, we identified an E3 ligase, NHL repeat-containing 1 (NHLRC1), that mediates frataxin ubiquitination degradation. Cardiac-specific overexpression of frataxin ameliorated myocardial I/R injury through ferroptosis inhibition.
CONCLUSIONS
Through a multi-level study from molecule to animal model, these findings uncover the key role of frataxin in inhibiting cardiomyocyte ferroptosis and provide new strategies and perspectives for the treatment of myocardial I/R injury.
Topics: Mice; Animals; Ferroptosis; Chromatography, Liquid; Mice, Inbred C57BL; Tandem Mass Spectrometry; Myocardium; Myocytes, Cardiac; Myocardial Reperfusion Injury; Iron; Homeostasis; Ubiquitin-Protein Ligases; Frataxin
PubMed: 37343689
DOI: 10.1016/j.freeradbiomed.2023.06.016 -
Science Bulletin Aug 2023Myocardial fibrosis is the villain of sudden cardiac death. Myocardial ischemia/reperfusion (MI/R) injury induces cardiomyocyte damage or even death, which in turn...
Myocardial fibrosis is the villain of sudden cardiac death. Myocardial ischemia/reperfusion (MI/R) injury induces cardiomyocyte damage or even death, which in turn stimulates fibroblast activation and fibrosis, but the intercellular communication mechanism remains unknown. Recent studies have shown that small extracellular vesicles (sEVs) significantly contribute to intercellular communication. Whether and how sEV might mediate post-MI/R cardiomyocyte/fibroblasts communication remain unknown. Here, in vivo and in vitro MI/R models were established. We demonstrate that sEVs derived from cardiomyocyte (Myo-sEVs) carry mitochondrial components, which enter fibroblasts to initiate myocardial fibrosis. Based on bioinformatics screening and experimental verification, the activating molecule in Beclin1-regulated autophagy protein 1 (autophagy/beclin-1 regulator 1, Ambra1) was found to be a critical component of these sEV and might be a new marker for Myo-sEVs. Interestingly, release of Ambra1-Myo-sEVs was caused by secretory rather than canonical autophagy after MI/R injury and thereby escaped degradation. In ischemic and peripheral areas, Ambra1-Myo-sEVs were internalized by fibroblasts, and the delivered mtDNA components to activate the fibroblast cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway to promote fibroblast activation and proliferation. In addition, our data show that Ambra1 is expressed on the EV surface and cardiac-specific Ambra1 down regulation inhibits the Ambra1-Myo-sEVs release and fibroblast uptake, effectively inhibiting ischemic myocardial fibrosis. This finding newly provides the evidence that myocardial secretory autophagy plays a role in intercellular communication during cardiac fibrosis. Ambra1 is a newly characterized molecule with bioactivity and might be a marker for Myo-sEVs, providing new therapeutic targets for cardiac remodeling.
Topics: Humans; Myocardium; Myocytes, Cardiac; Myocardial Reperfusion Injury; Beclin-1; Fibrosis
PubMed: 37517989
DOI: 10.1016/j.scib.2023.07.030 -
European Heart Journal May 2024The Glu504Lys polymorphism in the aldehyde dehydrogenase 2 (ALDH2) gene is closely associated with myocardial ischaemia/reperfusion injury (I/RI). The effects of ALDH2...
BACKGROUND AND AIMS
The Glu504Lys polymorphism in the aldehyde dehydrogenase 2 (ALDH2) gene is closely associated with myocardial ischaemia/reperfusion injury (I/RI). The effects of ALDH2 on neutrophil extracellular trap (NET) formation (i.e. NETosis) during I/RI remain unknown. This study aimed to investigate the role of ALDH2 in NETosis in the pathogenesis of myocardial I/RI.
METHODS
The mouse model of myocardial I/RI was constructed on wild-type, ALDH2 knockout, peptidylarginine deiminase 4 (Pad4) knockout, and ALDH2/PAD4 double knockout mice. Overall, 308 ST-elevation myocardial infarction patients after primary percutaneous coronary intervention were enrolled in the study.
RESULTS
Enhanced NETosis was observed in human neutrophils carrying the ALDH2 genetic mutation and ischaemic myocardium of ALDH2 knockout mice compared with controls. PAD4 knockout or treatment with NETosis-targeting drugs (GSK484, DNase1) substantially attenuated the extent of myocardial damage, particularly in ALDH2 knockout. Mechanistically, ALDH2 deficiency increased damage-associated molecular pattern release and susceptibility to NET-induced damage during myocardial I/RI. ALDH2 deficiency induced NOX2-dependent NETosis via upregulating the endoplasmic reticulum stress/microsomal glutathione S-transferase 2/leukotriene C4 (LTC4) pathway. The Food and Drug Administration-approved LTC4 receptor antagonist pranlukast ameliorated I/RI by inhibiting NETosis in both wild-type and ALDH2 knockout mice. Serum myeloperoxidase-DNA complex and LTC4 levels exhibited the predictive effect on adverse left ventricular remodelling at 6 months after primary percutaneous coronary intervention in ST-elevation myocardial infarction patients.
CONCLUSIONS
ALDH2 deficiency exacerbates myocardial I/RI by promoting NETosis via the endoplasmic reticulum stress/microsomal glutathione S-transferase 2/LTC4/NOX2 pathway. This study hints at the role of NETosis in the pathogenesis of myocardial I/RI, and pranlukast might be a potential therapeutic option for attenuating I/RI, particularly in individuals with the ALDH2 mutation.
Topics: Animals; Female; Humans; Male; Mice; Middle Aged; Aldehyde Dehydrogenase, Mitochondrial; Benzamides; Benzodioxoles; Disease Models, Animal; Extracellular Traps; Leukotriene Antagonists; Leukotriene C4; Mice, Knockout; Myocardial Reperfusion Injury; Neutrophils; Protein-Arginine Deiminase Type 4; ST Elevation Myocardial Infarction
PubMed: 38666340
DOI: 10.1093/eurheartj/ehae205 -
Circulation Research Sep 2023
Topics: Humans; Myocardial Reperfusion Injury; Anti-Inflammatory Agents; Cytokines
PubMed: 37638415
DOI: 10.1161/CIRCRESAHA.123.322640 -
Nature Communications May 2024Sleep disorders increase the risk and mortality of heart disease, but the brain-heart interaction has not yet been fully elucidated. Cuproptosis is a copper-dependent...
Sleep disorders increase the risk and mortality of heart disease, but the brain-heart interaction has not yet been fully elucidated. Cuproptosis is a copper-dependent type of cell death activated by the excessive accumulation of intracellular copper. Here, we showed that 16 weeks of sleep fragmentation (SF) resulted in elevated copper levels in the male mouse heart and exacerbated myocardial ischemia-reperfusion injury with increased myocardial cuproptosis and apoptosis. Mechanistically, we found that SF promotes sympathetic overactivity, increases the germination of myocardial sympathetic nerve terminals, and increases the level of norepinephrine in cardiac tissue, thereby inhibits VPS35 expression and leads to impaired ATP7A related copper transport and copper overload in cardiomyocytes. Copper overload further leads to exacerbated cuproptosis and apoptosis, and these effects can be rescued by excision of the sympathetic nerve or administration of copper chelating agent. Our study elucidates one of the molecular mechanisms by which sleep disorders aggravate myocardial injury and suggests possible targets for intervention.
Topics: Animals; Myocytes, Cardiac; Male; Copper; Myocardial Reperfusion Injury; Mice; Sleep Deprivation; Apoptosis; Mice, Inbred C57BL; Copper-Transporting ATPases; Norepinephrine; Myocardium; Sympathetic Nervous System; Disease Models, Animal
PubMed: 38714741
DOI: 10.1038/s41467-024-48227-y -
Nutrients Jul 2023Ferroptosis is closely associated with the pathophysiology of myocardial ischemia. Hydroxysafflor yellow A (HSYA), the main active ingredient in the Chinese herbal...
Hydroxysafflor Yellow A Alleviates Acute Myocardial Ischemia/Reperfusion Injury in Mice by Inhibiting Ferroptosis via the Activation of the HIF-1α/SLC7A11/GPX4 Signaling Pathway.
Ferroptosis is closely associated with the pathophysiology of myocardial ischemia. Hydroxysafflor yellow A (HSYA), the main active ingredient in the Chinese herbal medicine safflower, exerts significant protective effects against myocardial ischemia/reperfusion injury (MI/RI). The aim of this study was to investigate the protective effects of HSYA against MI/RI and identify the putative underlying mechanisms. An in vivo model of acute MI/RI was established in C57 mice. Subsequently, the effects of HSYA on myocardial tissue injury were evaluated by histology. Lipid peroxidation and myocardial injury marker contents in myocardial tissue and serum and iron contents in myocardial tissue were determined using biochemical assays. Mitochondrial damage was assessed using transmission electron microscopy. H9C2 cardiomyocytes were induced in vitro by oxygen-glucose deprivation/reoxygenation, and ferroptosis inducer erastin was administered to detect ferroptosis-related indicators, oxidative-stress-related indicators, and expressions of ferroptosis-related proteins and HIF-1α. In MI/RI model mice, HSYA reduced myocardial histopathological damage, ameliorated mitochondrial damage in myocardial cells, and decreased total cellular iron and ferrous ion contents in myocardial tissue. HSYA increased the protein levels of SLC7A11, HIF-1α, and GPX4 and mitigated erastin- or HIF-1α siRNA-induced damage in H9C2 cells. In summary, HSYA alleviated MI/RI by activating the HIF-1α/SLC7A11/GPX4 signaling pathway, thereby inhibiting ferroptosis.
Topics: Mice; Animals; Myocardial Reperfusion Injury; Ferroptosis; Signal Transduction; Quinones; Reperfusion Injury
PubMed: 37571350
DOI: 10.3390/nu15153411 -
JCI Insight Apr 2024Myocardial ischemia/reperfusion (MI/R) injury is a major cause of adverse outcomes of revascularization following myocardial infarction. Anaerobic glycolysis during...
Myocardial ischemia/reperfusion (MI/R) injury is a major cause of adverse outcomes of revascularization following myocardial infarction. Anaerobic glycolysis during myocardial ischemia is well studied, but the role of aerobic glycolysis during the early phase of reperfusion is incompletely understood. Lactylation of Histone H3 (H3) is an epigenetic indicator of the glycolytic switch. Heat shock protein A12A (HSPA12A) is an atypic member of the HSP70 family. In the present study, we report that, during reperfusion following myocardial ischemia, HSPA12A was downregulated and aerobic glycolytic flux was decreased in cardiomyocytes. Notably, HSPA12A KO in mice exacerbated MI/R-induced aerobic glycolysis decrease, cardiomyocyte death, and cardiac dysfunction. Gain- and loss-of-function studies demonstrated that HSPA12A was required to support cardiomyocyte survival upon hypoxia/reoxygenation (H/R) challenge and that its protective effects were mediated by maintaining aerobic glycolytic homeostasis for H3 lactylation. Further analyses revealed that HSPA12A increased Smurf1-mediated Hif1α protein stability, thus increasing glycolytic gene expression to maintain appropriate aerobic glycolytic activity to sustain H3 lactylation during reperfusion and, ultimately, improving cardiomyocyte survival to attenuate MI/R injury.
Topics: Animals; Mice; Heat-Shock Proteins; Myocardial Infarction; Myocardial Ischemia; Myocardial Reperfusion Injury; Myocytes, Cardiac
PubMed: 38421727
DOI: 10.1172/jci.insight.169125 -
Cell Communication and Signaling : CCS Aug 2023The cause of aggravation of diabetic myocardial damage is yet to be elucidated; damage to mitochondrial function has been a longstanding focus of research. During...
BACKGROUND
The cause of aggravation of diabetic myocardial damage is yet to be elucidated; damage to mitochondrial function has been a longstanding focus of research. During diabetic myocardial ischaemia-reperfusion (MI/R), it remains unclear whether reduced mitochondrial fusion exacerbates myocardial injury by generating free damaged mitochondrial DNA (mitoDNA) and activating the cGAS-STING pathway.
METHODS
In this study, a mouse model of diabetes was established (by feeding mice a high-fat diet (HFD) plus a low dose of streptozotocin (STZ)), a MI/R model was established by cardiac ischaemia for 2 h and reperfusion for 30 min, and a cellular model of glycolipid toxicity induced by high glucose (HG) and palmitic acid (PA) was established in H9C2 cells.
RESULTS
We observed that altered mitochondrial dynamics during diabetic MI/R led to increased mitoDNA in the cytosol, activation of the cGAS-STING pathway, and phosphorylation of the downstream targets TBK1 and IRF3. In the cellular model we found that cytosolic mitoDNA was the result of reduced mitochondrial fusion induced by HG and PA, which also resulted in cGAS-STING signalling and activation of downstream targets. Moreover, inhibition of STING by H-151 significantly ameliorated myocardial injury induced by MFN2 knockdown in both the cell and mouse models. The use of a fat-soluble antioxidant CoQ10 improved cardiac function in the mouse models.
CONCLUSIONS
Our study elucidated the critical role of cGAS-STING activation, triggered by increased cytosolic mitoDNA due to decreased mitochondrial fusion, in the pathogenesis of diabetic MI/R injury. This provides preclinical insights for the treatment of diabetic MI/R injury. Video Abstract.
Topics: Animals; Mice; Diabetes Mellitus; Disease Models, Animal; DNA, Mitochondrial; Ischemia; Mitochondria; Myocardial Reperfusion Injury; Nucleotidyltransferases; Reperfusion; GTP Phosphohydrolases
PubMed: 37537600
DOI: 10.1186/s12964-023-01216-y