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ETHNOPHARMACOLOGICAL RELEVANCE: The incidence and mortality of cerebrovascular diseases are increasing year by year. Cerebral ischemia-reperfusion injury (CIRI) is common in patients with ischemic stroke. Naoxintong (NXT) is composed of a variety of Chinese medicines and has the ability to treat CIRI. AIM OF THE STUDY: The aim of this study is to investigate whether NXT regulates mitophagy in CIRI based on network pharmacology analysis and experimental validation. MATERIALS AND METHODS: Oxygen and glucose deprivation/re-oxygenation (OGD/R, 2/22 h) model of PC12 cells and transient middle cerebral artery occlusion (tMCAO, 2/22 h) model of rats were established. Pharmacodynamic indicators include neurological deficit score, 2,3,5-triphenyte-trazoliumchloride (TTC) staining, hematoxylin-eosin (HE) staining and cell viability. Network pharmacology was used to predict pharmacological mechanisms. Pharmacological mechanism indexes include transmission electron microscopy (TEM), drug affinity responsive target stability (DARTS), cellular thermal shift assay (CETSA), immunohistochemistry (IHC), western blot (WB) and immunofluorescence (IF). Kevetrin (an agonists of p53) and pifithrin-α (an inhibitor of p53) used to detect the key role of p53 in mitophagy of NXT. RESULTS: NXT (1% serum containing NXT and 110 mg/kg) improved the damage of OGD/R PC12 cells and tMCAO rats, and this protective effect was related to the anti-oxidation and ability to promote mitophagy of NXT. NXT and pifithrin-α increased the expression of promoting-mitophagy targets (PINK1, PRKN and LC3B) and inhibited the expression of inhibiting-mitophagy targets (p52) via restraining p53, and finally accelerated mitophagy caused by CIRI. CONCLUSION: This study demonstrates that NXT promotes mitophagy in CIRI through restraining p53 and promoting PINK1/PRKN in vivo and in vitro.
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Medicamentos de Ervas Chinesas , Mitofagia , Farmacologia em Rede , Proteínas Quinases , Traumatismo por Reperfusão , Proteína Supressora de Tumor p53 , Animais , Masculino , Ratos , Isquemia Encefálica/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/patologia , Mitofagia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Células PC12 , Proteínas Quinases/metabolismo , Ratos Sprague-Dawley , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína LigasesRESUMO
BACKGROUND: Myocardial ischemia-reperfusion injury (MI/RI) is an unavoidable risk event for acute myocardial infarction, with ferroptosis showing close involvement. We investigated the mechanism of MI/RI inducing myocardial injury by inhibiting the ferroptosis-related SLC7A11/glutathione (GSH)/glutathione peroxidase 4 (GPX4) pathway and activating mitophagy. METHODS: A rat MI/RI model was established, with myocardial infarction area and injury assessed by TTC and H&E staining. Rat cardiomyocytes H9C2 were cultured in vitro, followed by hypoxia/reoxygenation (H/R) modeling and the ferroptosis inhibitor lipoxstatin-1 (Lip-1) treatment, or 3-Methyladenine or rapamycin treatment and overexpression plasmid (oe-SLC7A11) transfection during modeling. Cell viability and death were evaluated by CCK-8 and LDH assays. Mitochondrial morphology was observed by transmission electron microscopy. Mitochondrial membrane potential was detected by fluorescence dye JC-1. Levels of inflammatory factors, reactive oxygen species (ROS), Fe2+, malondialdehyde, lipid peroxidation, GPX4 enzyme activity, glutathione reductase, GSH and glutathione disulfide, and SLC7A11, GPX4, LC3II/I and p62 proteins were determined by ELISA kit, related indicator detection kits and Western blot. RESULTS: The ferroptosis-related SLC7A11/GSH/GPX4 pathway was repressed in MI/RI rat myocardial tissues, inducing myocardial injury. H/R affected GSH synthesis and inhibited GPX4 enzyme activity by down-regulating SLC7A11, thus promoting ferroptosis in cardiomyocytes, which was averted by Lip-1. SLC7A11 overexpression improved H/R-induced cardiomyocyte ferroptosis via the GSH/GPX4 pathway. H/R activated mitophagy in cardiomyocytes. Mitophagy inhibition reversed H/R-induced cellular ferroptosis. Mitophagy activation partially averted SLC7A11 overexpression-improved H/R-induced cardiomyocyte ferroptosis. H/R suppressed the ferroptosis-related SLC7A11/GSH/GPX4 pathway by inducing mitophagy, leading to cardiomyocyte injury. CONCLUSIONS: Increased ROS under H/R conditions triggered cardiomyocyte injury by inducing mitophagy to suppress the ferroptosis-related SLC7A11/GSH/GPX4 signaling pathway activation.
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Sistema y+ de Transporte de Aminoácidos , Modelos Animais de Doenças , Ferroptose , Glutationa , Mitofagia , Traumatismo por Reperfusão Miocárdica , Miócitos Cardíacos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Ratos Sprague-Dawley , Transdução de Sinais , Animais , Masculino , Ratos , Sistema y+ de Transporte de Aminoácidos/metabolismo , Sistema y+ de Transporte de Aminoácidos/genética , Linhagem Celular , Ferroptose/efeitos dos fármacos , Glutationa/metabolismo , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitofagia/efeitos dos fármacos , Infarto do Miocárdio/patologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Miócitos Cardíacos/efeitos dos fármacos , Estresse Oxidativo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Espécies Reativas de Oxigênio/metabolismoRESUMO
Progressive cardiac fibrosis, a hallmark of heart failure, remains poorly understood regarding Proprotein convertase subtilisin/kexin type 9 (PCSK9) 's role. This study aims to elucidate PCSK9's involvement in cardiac fibrosis. After ischemia/reperfusion (I/R) injury surgery in rats, PCSK9 inhibitors were used to examine their effects on the transforming growth factor-ß1 (TGF-ß1)/small mother against decapentaplegic 3 (Smad3) pathway and inflammation. Elevated PCSK9, TGF-ß1, and Smad3 levels were observed in cardiac tissues post-I/R injury, indicating fibrosis. PCSK9 inhibition reduced pro-fibrotic protein expression, protecting the heart and mitigating I/R-induced damage and fibrosis. Additionally, it ameliorated cardiac inflammation and reduced post-myocardial infarction (MI) size, improving cardiac function and slowing heart failure progression. PCSK9 inhibitors significantly attenuate myocardial fibrosis induced by I/R via the TGF-ß1/Smad3 pathway.
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BACKGROUND: Ischemia-reperfusion injury (IRI) stands as a major trigger for primary graft dysfunction (PGD) in lung transplantation (LTx). Especially in LTx from donation after cardiac death (DCD), effective control of IRI following warm ischemia (WIRI) is crucial to prevent PGD. This study aimed to identify the key factors affecting WIRI in LTx from DCD. METHODS: Previously reported RNA-sequencing dataset of lung WIRI was reanalyzed to identify nuclear receptor subfamily 4 group A member 1 (NR4A1) as the immediate early gene for WIRI. Dynamics of NR4A1 expression were verified using a mouse hilar clamp model. To investigate the role of NR4A1 in WIRI, a mouse model of LTx from DCD was established using Nr4a1 knockout (Nr4a1-/-) mice. RESULTS: NR4A1 was located around vascular cells, and its protein levels in the lungs increased rapidly and transiently during WIRI. LTï½ from Nr4a1-/- donors significantly improved pulmonary graft function compared to wild-type donors (P < 0.001). Histological analysis showed decreased microvascular endothelial cell death (P = 0.007), neutrophil infiltration (P < 0.001), and albumin leakage (P < 0.001). Evans blue permeability assay demonstrated maintained pulmonary microvascular barrier integrity in grafts from Nr4a1-/- donors, correlating with diminished pulmonary edema (P < 0.001). However, NR4A1 did not significantly affect the inflammatory response during WIRI, and IRI was not suppressed when a wild-type donor lung was transplanted into the Nr4a1-/- recipient. CONCLUSIONS: Donor NR4A1 plays a specialized role in the positive regulation of endothelial cell injury and microvascular hyperpermeability. These findings demonstrate the potential of targeting NR4A1 interventions to alleviate PGD and improve outcomes in LTx from DCD.
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Flap surgery is an integral part of plastic surgery, and ischemia-reperfusion (I/R) injury significantly affects the viability of the flap. Carvedilol (CRV), a nonselective beta-blocker with alpha-1 blocking and antioxidant properties, and known for its potential in reducing I/R damage, was chosen as the active substance for our study. The aim of this study was to investigate the vasodilator and antioxidant effects of CRV on rat inferior epigastric artery skin flap using orally disintegrating tablets (ODTs). The optimized ODT formulation was subjected to in vivo experiments using Sprague-Dawley female rats (n = 24) divided into three groups: Group I (control, I/R), Group II (treatment, I/R + CRV), and Group III (treatment, I/R), I/R + CRV ODT). Reperfusion was then observed following the release of the microclamp from the pedicle, and the flap was then re-adapted to its original position. Control rats were given oral isotonic solution via gavage and were subjected to 8 h of ischemia and 12 h of reperfusion. Group II was given 2 mg/kg CRV oral tablets for 7 days before and after surgery. Group III was given 2 mg/kg/day CRV ODT for the same period. Biopsies were taken from the flap and histopathological and biochemical analyses including superoxide dismutase, glutathionenitric oxide, malondialdehyde, paraoxonase 1, total oxidant, and total antioxidant capacities were performed. This study demonstrates that CRV ODTs significantly increased flap viability by approximately 25% compared to the control group, highlighting their promising therapeutic potential.
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BACKGROUND: Cerebral ischemic disease is a common cerebrovascular disease, especially ischemic stroke. Exercise has protective functions on brain tissues following cerebral ischemia-reperfusion injury (CIRI), but its preventive effects and mechanisms in CIRI remain unclear. We aimed to investigate the effects and mechanisms of exercise preconditioning on CIRI. METHODS: The middle cerebral artery occlusion (MCAO) operation was prepared to establish CIRI rats. All rats were randomized into the MCAO, exercise (exercise preconditioning plus MCAO operation), vector (exercise preconditioning, MCAO operation plus intraventricular injection of empty vector), and tissue inhibitor of metalloprotease 1 overexpression (OE-TIMP1, exercise preconditioning, MCAO operation plus intraventricular injection of OE-TIMP1) groups. RESULTS: The results indicated that exercise preconditioning suppressed approximately 66.67% of neurological deficit scores and 73.79% of TIMP1 mRNA expression in MCAO rats, which were partially offset by OE-TIMP1. The protective effects of exercise against neuron death status and cerebral infarction size in MCAO rats were reversed by OE-TIMP1. It also confirmed that exercise weakened apoptosis and oxidative stress damage, with notable increases of B-cell lymphoma-2, superoxide dismutase, and glutathione peroxidase production, and evident decreases of BCL2-associated X, caspase 3, and malondialdehyde in MCAO rats, while these effects were partially reversed by OE-TIMP1. Additionally, the inhibitory effects of exercise on the protein levels of TIMP1, hypoxia-inducible factor-alpha, vascular endothelial growth factor receptor 2, vascular endothelial growth factor, and neurogenic locus notch homolog protein 1 in MCAO rats were partially reversed by OE-TIMP1. CONCLUSION: Altogether, exercise preconditioning had protective effects on CIRI by restraining TIMP1, which provided new therapeutic strategies for preventing CIRI.
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Isquemia Encefálica , Infarto da Artéria Cerebral Média , Condicionamento Físico Animal , Traumatismo por Reperfusão , Inibidor Tecidual de Metaloproteinase-1 , Animais , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Ratos , Masculino , Isquemia Encefálica/prevenção & controle , Isquemia Encefálica/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Estresse Oxidativo , Apoptose , Ratos Sprague-Dawley , Modelos Animais de Doenças , Lesões Encefálicas/prevenção & controle , Lesões Encefálicas/etiologia , Lesões Encefálicas/metabolismoRESUMO
Myocardial ischemia-reperfusion (IR) injury is a severe rhythmic disease with a high prevalence in the early morning. IR injury has a significant circadian rhythm in reactive oxygen species (ROS) and inflammation levels. The development of rhythmic drugs has become a priority in myocardial IR injury. In this study, resveratrol (RES) and proanthocyanidins (OPC) were utilized to design nanoparticles (NPs), with hyaluronic acid (HA) as the core, grafted with MMP-targeting peptides to improve delivery to injured myocardial regions (HA-RES-OPC-MMP NPs). NPs significantly scavenged ROS, attenuated inflammation, and activated the rhythm gene. Notably, the difference in therapeutic effects on myocardial IR injury in mice at Zeitgeber time (ZT)1 and ZT13 confirms that NPs are rhythm-dependent drugs. At ZT13, echocardiographic and MRI confirm that IR injury in mice was not as severe as at ZT1, yet NPs were also less effective in treatment. Further, Per1/2 knockout mice confirmed the rhythm-dependent treatment of myocardial IR injury by NPs. Molecular studies have shown that rhythmic characteristics of inflammation and Sirt1 transcript levels are the main reasons for the different rhythmic therapeutic effects of NPs. Circadian rhythm-dependent treatment of HA-RES-OPC-MMP NPs has excellent potential for more precise treatment of myocardial IR injury in the future.
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Ritmo Circadiano , Traumatismo por Reperfusão Miocárdica , Nanopartículas , Resveratrol , Animais , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Nanopartículas/química , Camundongos , Resveratrol/farmacologia , Resveratrol/química , Ritmo Circadiano/efeitos dos fármacos , Camundongos Knockout , Masculino , Proantocianidinas/química , Proantocianidinas/farmacologia , Ácido Hialurônico/química , Espécies Reativas de Oxigênio/metabolismo , Camundongos Endogâmicos C57BL , Sirtuína 1/metabolismo , Proteínas Circadianas Period/metabolismo , Proteínas Circadianas Period/genética , Polifenóis/química , Polifenóis/farmacologiaRESUMO
Lung transplantation is the only definitive therapy for end-stage pulmonary disease. Less than 20â¯% of offered lungs are successfully transplanted due to a limited ischemic time window and poor donor lung quality manifested by pulmonary edema, hypoxia, or trauma. Therefore, poor donor organ recovery and utilization are significant barriers to wider implementation of the life-saving therapy of transplantation. While ischemia reperfusion injury (IRI) is often identified as the underlying molecular insult leading to immediate poor lung function in the post-operative period, this injury encompasses several pathways of cellular injury in addition to the recruitment of the innate immune system to the site of injury to propagate this inflammatory cascade. Pyroptosis is a central molecular inflammatory pathway that is the most significant contributor to injury in this early post-operative phase. Pyroptosis is another form of programmed cell death and is often associated with IRI. The mitigation of pyroptosis in the early post-operative period following lung transplantation is a potential novel way to prevent poor allograft function and improve outcomes for all recipients. Here we detail the pyroptotic pathway, its importance in lung transplantation, and several therapeutic modalities that can mitigate this harmful inflammatory pathway.
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OBJECTIVE: Although IL-38 is recognized for its regulatory role in a spectrum of chronic inflammatory diseases, investigations into its cardiac physiological and pathophysiological functions are nascent. Our aim was to delineate the biological impact of IL-38 in the context of myocardial ischemia-reperfusion injury (MIRI) and to uncover the mechanisms through which it exerts its effects. METHODS AND RESULTS: In this study, we used an MIRI mouse model, LPS/ATP stimulation, and a hypoxia/reoxygenation cell model to determine the regulatory influence of IL-38 on MIRI. We observed that the administration of recombinant IL-38 to mice led to a reduction in infarct size, an enhancement in cardiac function, and a suppression of NLRP3 inflammasome activation. In contrast, genetic deletion of IL-38 was associated with an increase in infarct size, worsening of cardiac function, and upregulation of NLRP3 inflammasome activity. The detrimental effects associated with the absence of IL-38 were mitigated by the administration of a specific NLRP3 inhibitor, suggesting that the inhibition of NLRP3 is a critical component of the protective effect mediated by IL-38 in MIRI. In vitro assays revealed that IL-38 inhibited NLRP3 inflammasome activation in cardiac fibroblasts through the engagement of IL-1R8 and the modulation of SYK phosphorylation. Silencing of IL-1R8 negated the suppressive effect of IL-38 on the NLRP3 inflammasome. CONCLUSION: IL-38 acts as a potent negative regulator of inflammasome activation after MIRI. It achieves this regulatory effect within cardiac fibroblasts by inhibiting SYK phosphorylation, a process mediated by IL-1R8.
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Dysregulation of Th17 and Treg cells contributes to the pathophysiology of cerebral ischemia. Metabolic changes of peripheral CD4+ T cells lead to the imbalance of Treg/Th17 polarization, which represents a promising strategy for post-stroke therapy. Polyphyllin VII (PVII), a steroidal saponin extracted from traditional Chinese herb Rhizoma Paridis, has multiple bioactivities, but the potential function of PVII in cerebral ischemia-reperfusion injury is not elucidated yet. In our study, a mouse transient middle cerebral artery occlusion (MCAO) model was constructed. TTC staining, H&E staining, TUNEL staining, ELISA assay, flow cytometry, western blot, RT-qPCR, Open-field test, Morris water maze test, hanging wire test, rotarod test and foot-fault test were performed to evaluate the potential function of PVII in MCAO mice. We found that PVII showed protective effects on cerebral ischemia-reperfusion injury by reducing infarct volume, ameliorating brain injury and neuroinflammation, and improving long-term functional recovery of MCAO mice. PVII promoted Treg infiltration and suppressed infiltration of Th1/Th17 cells in ischemic brain in vivo. Moreover, PVII impaired peripheral CD4+ T cell activation and modulated Treg/Th17 differentiation in vitro. Mechanistically, PVII suppressed mTORC1 activation to influence glycolytic metabolism and ROS generation of T cells, thus leads to the imbalance of Treg/Th17 polarization towards Treg skewed. Furthermore, reactivation of mTORC1 by MHY1485 abolished the influence of PVII on brain injury and neuroinflammation in MCAO mice. Our data provided a novel role of PVII in cerebral ischemia-reperfusion injury via manipulating Treg/Th17 imbalance.
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Mammalian mitochondrial DNA (mtDNA) encodes a total of 13 proteins, all of which are subunits of enzyme complexes of the oxidative phosphorylation. The mtDNA-encoded protein synthesis depends on the mitochondrial ribosomal proteins (MRPs), which assemble to form a specialized form of ribosome. Some mtDNA-encoded proteins have been reported to be reduced after myocardial ischemic injury. However, the molecular mechanisms responsible for this decrease and whether this decrease is involved in myocardial ischemia/reperfusion (I/R) injury remains unknown. Here, we found that the mtDNA-encoded protein levels were significantly decreased after I/R injury, while the mRNA levels of these genes were either increased or had no significant change. Subsequently, by querying and analyzing public database resources, we found that the expression of many mitochondrial translation-related proteins tended to decrease after myocardial infarction injury, and the reduction in the expression of these proteins was most obvious for Mrpl42. Furthermore, we found that cardiac Mrpl42 knockdown aggravated I/R-induced cardiac contractile dysfunction and cardiomyocyte death, while restoring Mrpl42 expression in the heart reduced I/R injury. Mrpl42 knockdown impaired the translation of mtDNA-encoded genes, ultimately led to aberrations in mitochondrial morphology and respiratory function. In addition, we found that the decrease in the expression of Mrpl42 after I/R injury was caused by the downregulation of Nrf2, which directly regulates Mrpl42 transcription. Our study revealed that ischemic downregulation of Mrpl42 expression and subsequent inhibition of mitochondrial translation contribute to cardiac I/R injury. Targeting Mrpl42 may be a novel therapeutic intervention for cardiac I/R injury and myocardial infarction.
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The purpose of this study was to investigate the protective effect and underlying mechanism of orexin A on cerebral ischemia-reperfusion injury, specifically through vasodilation mediated by the hypoxia inducible factor-1α (HIF-1α)-Endothelin-1(ET-1)/endothelial nitric oxide synthase (eNOS) pathway. A model of middle cerebral artery occlusion was established in both wild-type SD rats with exogenous orexin A intervention and in orexin A transgenic rats. Neurological deficit scores and cerebral infarction areas were assessed, and ischemic cortical blood flow was monitored. Gene and protein expression levels of HIF-1α, HIF-2α, ET-1, and three types of NOS were detected using real-time RT-qPCR and Western blot analysis, respectively. Additionally, nitric oxide (NO) levels in the cortex were analyzed through biochemical detection methods. Orexin A demonstrated a protective effect by reducing cerebral infarction and improving neurological deficits, which was achieved by increasing cortical blood flow during reperfusion. This protective mechanism was associated with upregulated HIF-1α expression, downregulated ET-1 expression, upregulated eNOS expression, and increased NO production. This study demonstrates the protective effect of orexin A on cerebral ischemia-reperfusion injury, achieved by regulating the release of vasomotor substances to enhance cortical blood flow during reperfusion. These findings suggest that orexin A may represent a potential therapeutic strategy for ischemic stroke.
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BACKGROUND: The role of histone methyltransferase SETDB1 in renal ischemia-reperfusion (I/R) injury has not been explored yet. This study aims to investigate the potential mechanism of SETDB1 in regulating renal I/R injury and its impact on mitochondrial damage and oxidative stress. METHODS: The in vivo model of renal I/R in mice and the in vitro model of hypoxia/reoxygenation (H/R) in human renal tubular epithelial cells (HK-2) were constructed to detect the expression of SETDB1. Next, the specific inhibitor (R,R)-59 and knockdown viruses were used to inhibit SETDB1 and verify its effects on mitochondrial damage and oxidative stress. Chromatin immunoprecipitation (ChIP) and coimmunoprecipitation (CoIP) were implemented to explore the in-depth mechanism of SETDB1 regulating renal I/R injury. RESULTS: The study found that SETDB1 had a regulatory role in mitochondrial damage and oxidative stress during renal I/R injury. Notably, SESN2 was identified as a target of SETDB1, and its expression was under the influence of SETDB1. Besides, SESN2 mediated the regulation of SETDB1 on renal I/R injury. Through deeper mechanistic studies, we uncovered that SETDB1 collaborates with heterochromatin HP1ß, facilitating the labeling of H3K9me3 on the SESN2 promoter and impeding SESN2 expression. CONCLUSIONS: The SETDB1/HP1ß-SESN2 axis emerges as a potential therapeutic strategy for mitigating renal I/R injury.
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Histona-Lisina N-Metiltransferase , Rim , Traumatismo por Reperfusão , Humanos , Animais , Camundongos , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Rim/lesões , Rim/patologia , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Histona-Lisina N-Metiltransferase/metabolismo , Sestrinas/metabolismo , Estresse Oxidativo , Expressão Gênica , Regiões Promotoras Genéticas , Homólogo 5 da Proteína Cromobox/metabolismoRESUMO
This study aimed to elucidate the role and underlying mechanisms of Peroxisome proliferator-activated receptor gamma (PPARγ) and its m6A methylation in renal ischemia-reperfusion (I/R) injury and ferroptosis of tubular epithelial cells (TECs). High-throughput transcriptome sequencing was performed on renal tissue samples from I/R injury models and sham-operated mice, complemented by in vivo and in vitro experiments focusing on the PPARγ activator Rosiglitazone and the manipulation of METTL14 and IGF2BP2 expression. Key evaluations included renal injury assessment, ferroptosis indicator measurement, and m6A methylation analysis of PPARγ. Our findings highlight the critical role of the PPARγ pathway and ferroptosis in renal I/R injury, with Rosiglitazone ameliorating renal damage and TEC ferroptosis. METTL14-mediated m6A methylation of PPARγ, dependent on IGF2BP2, emerged as a pivotal regulator of PPARγ expression, renal injury, and ferroptosis. This study reveals that PPARγ m6A methylation, orchestrated by METTL14 through an IGF2BP2-dependent mechanism, plays a crucial role in mitigating renal I/R injury and TEC ferroptosis. These insights offer promising avenues for therapeutic strategies targeting acute kidney injury.
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Células Epiteliais , Ferroptose , PPAR gama , Traumatismo por Reperfusão , Rosiglitazona , PPAR gama/metabolismo , PPAR gama/genética , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/genética , Animais , Camundongos , Células Epiteliais/metabolismo , Masculino , Rosiglitazona/farmacologia , Túbulos Renais/metabolismo , Humanos , Metilação , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Metiltransferases/metabolismo , Metiltransferases/genética , Camundongos Endogâmicos C57BL , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/genética , Rim/metabolismoRESUMO
The endothelial glycocalyx (eGC) is a carbohydrate-rich layer on the vascular endothelium, and its damage can lead to endothelial and organ dysfunction. Heparanase (HPSE) degrades the eGC in response to cellular stress, but its role in organ dysfunction remains unclear. This study investigates HPSE's role in lung ischemia-reperfusion (I/R) injury. A left lung hilar occlusion model was used in B6 wildtype (WT) and HPSE genetic knockout (-/-) mice to induce I/R injury in vivo. The left lungs were ischemic for 1 h followed by reperfusion for 4 h prior to investigations of lung function and eGC status. Data were compared between uninjured lungs and I/R-injured lungs in WT and HPSE-/- mice. WT lungs showed significant functional impairment after I/R injury, whereas HPSE-/- lungs did not. Inhibition or knockout of HPSE prevented eGC damage, inflammation, and cellular migration after I/R injury by reducing matrix metalloproteinase activities. HPSE-/- mice exhibited compensatory regulation of related gene expressions. HPSE facilitates eGC degradation leading to inflammation and impaired lung function after I/R injury. HPSE may be a therapeutic target to attenuate graft damage in lung transplantation.
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Glucuronidase , Glicocálix , Pulmão , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão , Animais , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Glicocálix/metabolismo , Masculino , Glucuronidase/metabolismo , Glucuronidase/genética , Camundongos , Pulmão/metabolismo , Pulmão/patologia , Camundongos Knockout , Endotélio Vascular/metabolismo , Endotélio Vascular/patologiaRESUMO
Numerous cardioprotective interventions have been reported to reduce myocardial infarct size (IS) in pre-clinical studies. However, their translation for the benefit of patients with acute myocardial infarction (AMI) has been largely disappointing. One reason for the lack of translation is the lack of rigor and reproducibility in pre-clinical studies. To address this, we have established the European IMproving Preclinical Assessment of Cardioprotective Therapies (IMPACT) pig AMI network with centralized randomization and blinded core laboratory IS analysis and validated the network with ischemic preconditioning (IPC) as a positive control. Ten sites in the COST Innovators Grant (IG16225) network participated in the IMPACT network. Three sites were excluded from the final analysis through quality control of infarct images and use of pre-defined exclusion criteria. Using a centrally generated randomization list, pigs were allocated to myocardial ischemia/reperfusion (I/R, N = 5/site) or IPC + I/R (N = 5/site). The primary endpoint was IS [% area-at-risk (AAR)], as quantified by triphenyl-tetrazolium-chloride (TTC) staining in a centralized, blinded core laboratory (5 sites), or IS [% left-ventricular mass (LV)], as quantified by a centralized, blinded cardiac magnetic resonance (CMR) core laboratory (2 sites). In pooled analyses, IPC significantly reduced IS when compared to I/R (57 ± 14 versus 32 ± 19 [%AAR] N = 25 pigs/group; p < 0.001; 25 ± 13 versus 14 ± 8 [%LV]; N = 10 pigs/group; p = 0.021). In site-specific analyses, in 4 of the 5 sites, IS was significantly reduced by IPC when compared to I/R when quantified by TTC and in 1 of 2 sites when quantified by CMR. A pig AMI multicenter European network with centralized randomization and core blinded IS analysis was established and validated with the aim to improve the reproducibility of cardioprotective interventions in pre-clinical studies and the translation of cardioprotection for patient benefit.
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OBJECTIVE: Renal IRI is one of the leading causes of AKI. How to effectively mitigate renal IRI is important for the recovery of renal function. The regulatory mechanism of lycopene, a natural antioxidant, in renal IRI is currently unknown. Therefore, we utilized network pharmacology and animal experiments to explore the possible mechanisms and potential targets of lycopene for alleviating renal IRI. METHODS: We obtained lycopene-regulated genes and renal IRI-related genes from the CTD database and GeneCards database, respectively. Subsequently, the two were intersected and the intersecting genes we defined as lycopene-regulated genes in renal IRI. Next, we explored their potential biological functions and mechanisms through enrichment analysis. Meanwhile, we constructed a rat renal IRI model and validated the protective effects of lycopene and related mechanisms. To further explore the Hub genes regulated by lycopene, we constructed a PPI protein interactions network and characterized the Hub genes using Cytoscape software. We also verified the expression of Hub genes using animal experiments and molecular docking techniques. Finally, we constructed TF-Hub gene and miRNA-Hub gene regulatory networks. RESULTS: We obtained a total of 255 lycopene-regulated genes and 327 renal IRI-related genes. The enrichment analysis revealed that they were closely related to the regulation of oxidative stress as well as the regulation of inflammatory factors. At the same time, the MAPK signaling pathway was significantly enriched. Next, we found in animal experiments that lycopene significantly alleviated the level of oxidative stress and inflammation during renal IRI, and had a protective effect on kidney damage. Also, we found that this protective effect may be achieved by inhibiting the MAPK signaling pathway. Next, we identified a total of five Hub genes using Cytoscape software: TNF, AKT1, MAPK3, IL6 and CASP3. Both animal experiments and molecular docking techniques demonstrated that lycopene can effectively regulate the expression of Hub genes. Finally, our constructed TF-Hub gene and miRNA-Hub gene regulatory network provide a theoretical basis for further regulation of Hub genes in follow-up. CONCLUSIONS: This study suggests that lycopene is a promising option in mitigating renal IRI. Lycopene may exert protective effects by inhibiting the MAPK signaling pathway.
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BACKGROUND: Acute myocardial ischemia/reperfusion injury (MIRI) with complicated mechanisms contributes to a high risk of ventricular arrhythmia, high lethality, and even sudden death. In vitro, Fraxinellone (FRA) exhibits an array of biologic activities and may possess cardioprotective effects. However, no relevant studies have examined FRA's protective potential against MIRI and related ventricular arrhythmias. The present study was undertaken to determine the effectiveness of FRA on MIRI and ventricular fibrillation (VF) susceptibility in rats and to elucidate the underlying mechanisms. METHODS: 48 healthy male Sprague-Dawley (SD) rats were randomly divided into the following four groups: Sham+vehicle(n=12), Sham+FRA(n=12), I/R+vehicle(n=12) and I/R+FRA(n=12). Histopathology, electrophysiological examination, HRV analysis in combination with molecular biology were used to investigate the therapeutic benefits of FRA on cardiac injury and VF susceptibility during myocardial IR. Finally, the potential mechanism by which FRA protects myocardium from MIRI was explored. RESULTS: Pretreatment with FRA ameliorated myocardial fibrosis after MIRI in vivo, alleviated myocardial injury, inflammation, oxidative stress and apoptosis in vivo and in vitro, thereby protecting myocardium from MIRI injury. In addition, FRA administration could improve HRV, prolong ventricular effective refractory period (ERP) and action potential duration (APD), attenuate VF induction rate, and contribute to improving ventricular sympathetic nerve remodeling and ion channel remodeling. Mechanistically, FRA may reduce MIRI via the PI3K/AKT pathway. CONCLUSION: FRA may exert cardioprotective effects during MIRI by inhibiting myocardial inflammation, oxidative stress and apoptosis, and decrease VF susceptibility by improving sympathetic remodeling and ion channel remodeling, which might represent a potential therapeutic strategy for attenuation of MIRI.
RESUMO
Oxidative stress triggered by testicular torsion and detorsion in young males could negatively impact future fertility. Using a rat animal model for testicular IRI (tIRI), we aim to study the induction of autophagy (ATG) during testicular ischemia and tIRI and the role of oxidative-stress-induced c-Jun N-terminal Kinase (JNK) as a cytoprotective mechanism. Sixty male Sprague-Dawley rats were divided into five groups: sham, ischemia only, ischemia+SP600125 (a JNK inhibitor), tIRI only, and tIRI+SP600125. The tIRI rats underwent an ischemic injury for 1 h followed by 4 h of reperfusion, while ischemic rats were subjected to 1 h of ischemia only without reperfusion. Testicular-ischemia-induced Beclin 1 and LC3B expression was associated with decreased p62/SQSTM1 expression, increased ATP and alkaline phosphatase (AP) activity, and slightly impaired spermatogenesis. SP600125 treatment improved p62 expression and reduced the levels of Beclin 1 and LC3B but did not affect ATP or AP levels. The tIRI-induced apoptosis lowered the expression of the three ATG proteins and AP activity, activated caspase 3, and caused spermatogenic arrest. SP600125-inhibited JNK during tIRI restored sham levels to all investigated parameters. This study emphasizes the regulatory role of JNK in balancing autophagy and apoptosis during testicular oxidative injuries.