Single-cell transcriptomics in MI identify Slc25a4 as a new modulator of mitochondrial malfunction and apoptosis-associated cardiomyocyte subcluster.

Myocardial infarction (MI) is the leading cause of premature death. The death of cardiomyocytes (CMs) and the dysfunction of the remaining viable CMs are the main pathological factors contributing to heart failure (HF) following MI. This study aims to determine the transcriptional profile of CMs and investigate the heterogeneity among CMs under hypoxic conditions. Single-cell atlases of the heart in both the sham and MI groups were developed using single-cell data (GSE214611) downloaded from Gene Expression Omnibus (GEO) database ( https://www.ncbi.nlm.nih.gov/geo/ ). The heterogeneity among CMs was explored through various analyses including enrichment, pseudo time, and intercellular communication analysis. The marker gene of C5 was identified using differential expression analysis (DEA). Real-time polymerase chain reaction (RT-PCR), bulk RNA-sequencing dataset analysis, western blotting, immunohistochemical and immunofluorescence staining, Mito-Tracker staining, TUNEL staining, and flow cytometry analysis were conducted to validate the impact of the marker gene on mitochondrial function and cell apoptosis of CMs under hypoxic conditions. We identified a cell subcluster named C5 that exhibited a close association with mitochondrial malfunction and cellular apoptosis characteristics, and identified Slc25a4 as a significant biomarker of C5. Furthermore, our findings indicated that the expression of Slc25a4 was increased in failing hearts, and the downregulation of Slc25a4 improved mitochondrial function and reduced cell apoptosis. Our study significantly identified a distinct subcluster of CMs that exhibited strong associations with ventricular remodeling following MI. Slc25a4 served as the hub gene for C5, highlighting its significant potential as a novel therapeutic target for MI.

CREG1 deficiency impaired myoblast differentiation and skeletal muscle regeneration.

BACKGROUND: CREG1 (cellular repressor of E1A-stimulated genes 1) is a protein involved in cellular differentiation and homeostasis regulation. However, its role in skeletal muscle satellite cells differentiation and muscle regeneration is poorly understood. This study aimed to investigate the role of CREG1 in myogenesis and muscle regeneration. METHODS: RNA sequencing data (GSE8479) was analysed from the Gene Expression Omnibus database (GEO, https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi). We generated Creg1 knockdown and skeletal muscle satellite cells specific Creg1 overexpression mice mediated by adeno-associated virus serotype 9 (AAV9), skeletal muscle mature myofibre Creg1 knockout mice (myoblast/Creg1MKO), and control mice Creg1flox/flox (Creg1fl/fl) as in vivo models. The mice were injected into tibialis anterior (TA) muscle with 100 µL of 10 µM cardiotoxin to establish a muscle regeneration model. Creg1fl/fl and Creg1MKO mice were treated with AAV-sh-C-Cbl (2 × 1010 genomic copies/mouse) to silence C-Cbl in the TA muscle. 293T and C2C12 cells were transfected with plasmids using lipofectamine RNAi MAX in vitro. Mass spectrometry analyses and RNA sequencing transcriptomic assay were performed. RESULTS: We analysed the transcriptional profiles of the skeletal muscle biopsies from healthy older (N = 25) and younger (N = 26) adult men and women in GSE8479 database, and the results showed that Creg1 was associated with human sarcopenia. We found that Creg1 knockdown mice regenerated less newly formed fibres in response to cardiotoxin injection (~30% reduction, P < 0.01); however, muscle satellite cells specific Creg1 overexpression mice regenerated more newly formed fibres (~20% increase, P < 0.05). AMPKa1 is known as a key mediator in the muscle regeneration process. Our results revealed that CREG1 deficiency inhibited AMPKa1 signalling through C-CBL E3-ubiquitin ligase-mediated AMPKa1 degradation (P < 0.01). C-CBL-mediated AMPKa1 ubiquitination was attributed to the K48-linked polyubiquitination of AMPKa1 at K396 and that the modification played an important role in the regulation of AMPKa1 protein stability. We also found that Creg1MKO mice regenerated less newly formed fibres compared with Creg1fl/fl mice (~30% reduction, P < 0.01). RNA-seq analysis showed that CREG1 deletion in impaired muscles led to the upregulation of inflammation and DKK3 expression. The TA muscles of Creg1MKO mice were injected with AAV-vector or AAV-shC-Cbl, silencing C-CBL (P < 0.01) in the skeletal muscles of Creg1MKO mice significantly improved muscle regeneration induced by CTX injury (P < 0.01). CONCLUSIONS: Our findings suggest that CREG1 may be a potential therapeutic target for skeletal muscle regeneration.

Unraveling the molecular links between benzopyrene exposure, NASH, and HCC: an integrated bioinformatics and experimental study.

Benzopyrene (B[a]P) is a well-known carcinogen that can induce chronic inflammation and fibrosis in the liver, leading to liver disease upon chronic exposure. Nonalcoholic steatohepatitis (NASH) is a chronic liver condition characterized by fat accumulation, inflammation, and fibrosis, often resulting in hepatocellular carcinoma (HCC). In this study, we aimed to investigate the intricate connections between B[a]P exposure, NASH, and HCC. Through comprehensive bioinformatics analysis of publicly available gene expression profiles, we identified differentially expressed genes (DEGs) associated with B[a]P exposure, NASH, and liver cancer. Furthermore, network analysis revealed hub genes and protein-protein interactions, highlighting cellular metabolic dysfunction and disruption of DNA damage repair in the B[a]P-NASH-HCC process. Notably, HSPA1A and PPARGC1A emerged as significant genes in this pathway. To validate their involvement, we conducted qPCR analysis on cell lines and NASH mouse liver tissues and performed immunohistochemistry labeling in mouse and human HCC liver sections. These findings provide crucial insights into the potential regulatory mechanisms underlying benzopyrene-induced hepatotoxicity, shedding light on the pathogenesis of B[a]P-associated NASH and HCC. Moreover, our study suggests that HSPA1A and PPARGC1A could serve as promising therapeutic targets. Enhancing our understanding of their regulatory roles may facilitate the development of targeted therapies, leading to improved patient outcomes.

The CREG1-FBXO27-LAMP2 axis alleviates diabetic cardiomyopathy by promoting autophagy in cardiomyocytes.

Autophagy plays an important role in the development of diabetic cardiomyopathy. Cellular repressor of E1A-stimulated genes 1 (CREG1) is an important myocardial protective factor. The aim of this study was to investigate the effects and mechanisms of CREG1 in diabetic cardiomyopathy. Male C57BL/6 J mice, Creg1 transgenic mice and cardiac-specific knockout mice were used to establish a type 2 diabetes model. Small animal ultrasound, Masson's staining and western blotting were used to evaluate cardiac function, myocardial fibrosis and autophagy. Neonatal mouse cardiomyocytes (NMCMs) were stimulated with palmitate, and the effects of CREG1 on NMCMs autophagy were examined. CREG1 deficiency exacerbated cardiac dysfunction, cardiac hypertrophy and fibrosis in mice with diabetic cardiomyopathy, which was accompanied by exacerbated autophagy dysfunction. CREG1 overexpression improved cardiac function and ameliorated cardiac hypertrophy and fibrosis in diabetic cardiomyopathy by improving autophagy. CREG1 protein expression was decreased in palmitate-induced NMCMs. CREG1 knockdown exacerbated cardiomyocyte hypertrophy and inhibited autophagy. CREG1 overexpression inhibited cardiomyocyte hypertrophy and improved autophagy. LAMP2 overexpression reversed the effect of CREG1 knockdown on palmitate-induced inhibition of cardiomyocyte autophagy. CREG1 inhibited LAMP2 protein degradation by inhibiting the protein expression of F-box protein 27 (FBXO27). Our findings indicate new roles of CREG1 in the development of diabetic cardiomyopathy.

The role of CREG1 in megakaryocyte maturation and thrombocytopoiesis.

Abnormal megakaryocyte maturation and platelet production lead to platelet-related diseases and impact the dynamic balance between hemostasis and bleeding. Cellular repressor of E1A-stimulated gene 1 (CREG1) is a glycoprotein that promotes tissue differentiation. However, its role in megakaryocytes remains unclear. In this study, we found that CREG1 protein is expressed in platelets and megakaryocytes and was decreased in the platelets of patients with thrombocytopenia. A cytosine arabinoside-induced thrombocytopenia mouse model was established, and the mRNA and protein expression levels of CREG1 were found to be reduced in megakaryocytes. We established megakaryocyte/platelet conditional knockout (Creg1pf4-cre) and transgenic mice (tg-Creg1). Compared to Creg1fl/fl mice, Creg1pf4-cre mice exhibited thrombocytopenia, which was mainly caused by inefficient bone marrow (BM) thrombocytopoiesis, but not by apoptosis of circulating platelets. Cultured Creg1pf4-cre-megakaryocytes exhibited impairment of the actin cytoskeleton, with less filamentous actin, significantly fewer proplatelets, and lower ploidy. CREG1 directly interacts with MEK1/2 and promotes MEK1/2 phosphorylation. Thus, our study uncovered the role of CREG1 in the regulation of megakaryocyte maturation and thrombopoiesis, and it provides a possible theoretical basis for the prevention and treatment of thrombocytopenia.

FGF21-FGFR1 controls mitochondrial homeostasis in cardiomyocytes by modulating the degradation of OPA1.

Fibroblast growth factor 21 (FGF21) is a pleiotropic hormone secreted primarily by the liver and is considered a major regulator of energy homeostasis. Recent research has revealed that FGF21 could play an important role in cardiac pathological remodeling effects and prevention of cardiomyopathy; however, the underlying mechanism remains largely unknown. This study aimed to determine the mechanism underlying the cardioprotective effects of FGF21. We engineered FGF21 knock out mice and subsequently elucidated the effects of FGF21 and its downstream mediators using western blotting, qRT-PCR, and mitochondrial morphological and functional analyses. FGF21 knockout mice showed cardiac dysfunction, accompanied by a decline in global longitudinal strain (GLS) and ejection fraction (EF), independent of metabolic disorders. Mitochondrial quality, quantity, and function were abnormal, accompanied by decreased levels of optic atrophy-1 (OPA1) in FGF21 KO mice. In contrast to FGF21 knockout, cardiac-specific overexpression of FGF21 alleviated the cardiac dysfunction caused by FGF21 deficiency. In an in vitro study, FGF21 siRNA deteriorated mitochondrial dynamics and impaired function induced by cobalt chloride (CoCl2). Both recombinant FGF21 and adenovirus-mediated FGF21 overexpression could alleviate CoCl2-induced mitochondrial impairment by restoring mitochondrial dynamics. FGF21 was essential for maintaining mitochondrial dynamics and function of the cardiomyocytes. As a regulator of cardiomyocyte mitochondrial homeostasis under oxidative stress, FGF21 could be an important new target for therapeutic options for patients with heart failure.

MicroRNA-574-5p targeting HOXC6 expression inhibits the hepatocyte lipid uptake to alleviate non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) is one of the main causes of liver disease that has reached its last stage. Over the past few years, evidence for miRNAs' centrality in NAFLD pathogenesis has accumulated. According to some studies, miR-574-5p plays a role in lipid metabolism. However, research on the relationship between miR-574-5p and NAFLD is lacking. For in vivo experiments, we induced the NAFLD mice model with a high-fat diet (HFD). AgomiR-574-5p was injected intravenously into HFD-fed mice for eight weeks, and qPCR was used to identify the expression of miR-574-5p in the serum. In in vitro experiments, The treatment of L-O2 cells with a miR-574-5p mimic resulted in a significant reduction in lipid deposition, suggesting that miR-574-5p can inhibit lipid accumulation and lipid formation induced by OA. The dual-luciferase reporter gene assay revealed that miR-574-5p targets the 3' UTR region of HOXC6 directly. We discovered that OA-induced lipid accumulation in hepatocytes might be mediated through the miR-574-5p-HOXC6 signaling axis. Additional research is required in order to determine the specific mechanism by which HOXC6 downstream pathways are involved in the miR-574-5p induced lipid uptake.

Corrigendum to "Orosomucoid 1 Attenuates Doxorubicin-Induced Oxidative Stress and Apoptosis in Cardiomyocytes via Nrf2 Signaling".

[This corrects the article DOI: 10.1155/2020/5923572.].

Gut microbiota induces high platelet response in patients with ST segment elevation myocardial infarction after ticagrelor treatment.

Background: Ticagrelor is a first-line drug for the treatment of acute ST elevation myocardial infarction (STEMI). However, approximately 20% STEMI patients taking ticagrelor exhibited a delayed response and the mechanism was still unclear. Methods: To explore the mechanism of the poor response of ticagrelor in post-percutaneous coronary intervention (PCI) patients, we enrolled 65 high platelet reactivity (HPR) patients and 90 controls (normal platelet reactivity [NPR]). Pharmacokinetic assessment result showed that the plasma concentrations of ticagrelor and its metabolism production, AR-C124910XX, were lower in HPR patients than controls. Further single nucloetide polymorphism (SNP) analysis identified that there is no difference in ATP binding cassette subfamily B member 1 (ABCB1) gene expression between the NPR group and the HPR group. Metagenomic and metabolomic analyses of fecal samples showed that HPR patients had higher microbial richness and diversity. Transplantation of the gut microbiota from HPR donors to microbiota-depleted mice obviously decreased plasma concentration of ticagrelor. Results: Our findings highlight that gut microbiota dysbiosis may be an important mechanism for the ticagrelor of HPR in patients with STEMI and support that modify gut microbiota is a potential therapeutic option for STEMI. Conclusions: Our findings highlight that gut microbiota dysbiosis may be an important mechanism for the ticagrelor of HPR in patients with ST elevation myocardial infarction (STEMI) and support that modify gut microbiota is a potential therapeutic option for STEMI. Funding: NSFC 82170297 and 82070300 from the National Natural Science Foundation of China.

Overexpression of MFN2 alleviates sorafenib-induced cardiomyocyte necroptosis via the MAM-CaMKIIδ pathway in vitro and in vivo.

Background: The continued success of oncological therapeutics is dependent on the mitigation of treatment-related adverse events, particularly cardiovascular toxicities. As such, there is an important need to understand the basic mechanisms of drug toxicities in the process of antitumor therapy. Our aim in this study was to elucidate the underlying mechanisms of sorafenib (sor)-induced cardiomyocyte damage. Methods: Primary mouse cardiomyocytes were prepared and treated with sor and various other treatments. Cardiomyocyte necroptosis was detected by flow cytometry, western blotting, and CCK8 assays. Mitochondrial Ca2+ uptake was detected by the Rhod-2 probe using confocal imaging. Morphological changes in mitochondria and mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs) were imaged using transmission electron microscopy (TEM) and confocal microscopy. Cardiac perfusion was performed to detect cardiac specific role of MFN2 overexpression in vivo. Results: We reported that mitochondrial Ca2+ overload, the subsequent increase in calmodulin-dependent protein kinase II delta (CaMKIIδ) and RIP3/MLKL cascade activation, contributed to sor-induced cardiac necroptosis. Excess MAM formation and close ER-mitochondria contact were key pathogenesis of sor-induced Ca2+ overload. Sor mediated MFN2 downregulation in a concentration-dependent manner. Furthermore, we found that reduced mitofusin-2 (MFN2) level augmented sor-mediated elevated MAM biogenesis and increased mitochondria-MAM tethering in cardiomyocytes. Sor-induced Mammalian Target of Rapamycin (mTOR) inactivation, followed by the activation and nuclear translocation of Transcription Factor EB (TFEB), contributed to mitophagy and MFN2 degradation. In an in vivo model, mice subjected to sor administration developed cardiac dysfunction, autophagy activation and necroptosis; our investigation found that global and cardiac-specific overexpression of MFN2 repressed cardiac dysfunction, and sor-induced cardiomyocyte necroptosis via repressing the MAM-CaMKIIδ-RIP3/MLKL pathway. Conclusion: Sorafenib mediated cardiomyocyte necroptosis through the MFN2-MAM-Ca2+-CaMKIIδ pathway in vitro and in vivo. The overexpression of MFN2 could rescue sor-induced cardiomyocyte necroptosis without disturbing the anti-tumor effects.

HOXA5-miR-574-5p axis promotes adipogenesis and alleviates insulin resistance.

Differentiation of preadipocytes into functional adipocytes could be a major target for repressing obesity-induced insulin resistance (IR). However, the molecular mechanisms involved in adipogenesis and the development of IR are unclear. We report, for the first time, that miR-574-5p, a novel miRNA, promotes adipogenesis to suppress IR. An increase in the level of miR-574-5p significantly induced the differentiation of preadipocytes into mature adipocytes. Conversely, reduction of miR-574-5p levels blocked the differentiation of preadipocytes in vitro. In a dual-luciferase reporter assay, it was shown that homeobox A5 (HOXA5) promoted the transcription of miR-574-5p to induce the differentiation of preadipocytes. Hdac9, a direct downstream target of miR-574-5p, was involved in the regulation of adipocyte differentiation. The overexpression of miR-574-5p also promoted adipogenesis in subcutaneous fat to alleviate IR in high-fat-diet-fed mice. Additionally, miR-574-5p expression was significantly higher in the subcutaneous adipose tissue of obese patients without type 2 diabetes than in those with type 2 diabetes. There was an increase in HOXA5 expression and a decrease in histone deacetylase 9 (HDAC9) expression in the subcutaneous fat of obese patients without type 2 diabetes. These results suggest that miR-574-5p may be a potential therapeutic target for combating obesity-related IR.

CREG ameliorates the phenotypic switching of cardiac fibroblasts after myocardial infarction via modulation of CDC42.

Phenotype switching of cardiac fibroblasts into myofibroblasts plays important role in cardiac fibrosis following myocardial infarction (MI). Cellular repressor of E1A-stimulated genes (CREG) protects against vascular and cardiac remodeling induced by angiotensin-II. However, the effects and mechanisms of CREG on phenotype switching of cardiac fibroblasts after MI are unknown. This study aimed to investigate the role of CREG on the phenotype switching of cardiac fibroblasts following MI and its mechanism. Our findings demonstrated that, compared with littermate control mice, cardiac function was deteriorated in CREG+/- mice on day 14 post-MI. Fibrosis size, αSMA, and collagen-1 expressions were increased in the border regions of CREG+/- mice on day 14 post-MI. Conversely, exogenous CREG protein significantly improved cardiac function, inhibited fibrosis, and reduced the expressions of αSMA and collagen-1 in the border regions of C57BL/6J mice on day 14. In vitro, CREG recombinant protein inhibited αSMA and collagen-1 expression and blocked the hypoxia-induced proliferation and migration of cardiac fibroblasts, which was mediated through the inhibition of cell division control protein 42 (CDC42) expression. Our findings could help in establishing new strategies based on the clarification of the role of the key molecule CREG in phenotype switching of cardiac fibroblasts following MI.

CREG1 improves the capacity of the skeletal muscle response to exercise endurance via modulation of mitophagy.

CREG1 (cellular repressor of E1A-stimulated genes 1) is involved in tissue homeostasis and influences macroautophagy/autophagy to protect cardiovascular function. However, the physiological and pathological role of CREG1 in the skeletal muscle is not clear. Here, we established a skeletal muscle-specific creg1 knockout mouse model (creg1;Ckm-Cre) by crossing the Creg1-floxed mice (Creg1fl/fl) with a transgenic line expressing Cre recombinase under the muscle-specific Ckm (creatine kinase, muscle) promoter. In creg1;Ckm-Cre mice, the exercise time to exhaustion and running distance were significantly reduced compared to Creg1fl/fl mice at the age of 9 months. In addition, the administration of recombinant (re)CREG1 protein improved the motor function of 9-month-old creg1;Ckm-Cre mice. Moreover, electron microscopy images of 9-month-old creg1;Ckm-Cre mice showed that the mitochondrial quality and quantity were abnormal and associated with increased levels of PINK1 (PTEN induced putative kinase 1) and PRKN/PARKIN (parkin RBR E3 ubiquitin protein ligase) but reduced levels of the mitochondrial proteins PTGS2/COX2, COX4I1/COX4, and TOMM20. These results suggested that CREG1 deficiency accelerated the induction of mitophagy in the skeletal muscle. Mechanistically, gain-and loss-of-function mutations of Creg1 altered mitochondrial morphology and function, impairing mitophagy in C2C12 cells. Furthermore, HSPD1/HSP60 (heat shock protein 1) (401-573 aa) interacted with CREG1 (130-220 aa) to antagonize the degradation of CREG1 and was involved in the regulation of mitophagy. This was the first time to demonstrate that CREG1 localized to the mitochondria and played an important role in mitophagy modulation that determined skeletal muscle wasting during the growth process or disease conditions.Abbreviations: CCCP: carbonyl cyanide m-chlorophenylhydrazone; CKM: creatine kinase, muscle; COX4I1/COX4: cytochrome c oxidase subunit 4I1; CREG1: cellular repressor of E1A-stimulated genes 1; DMEM: dulbecco's modified eagle medium; DNM1L/DRP1: dynamin 1-like; FCCP: carbonyl cyanide p-trifluoro-methoxy phenyl-hydrazone; HSPD1/HSP60: heat shock protein 1 (chaperonin); IP: immunoprecipitation; MAP1LC3B/LC3B: microtubule-associated protein 1 light chain 3 beta; MFF: mitochondrial fission factor; MFN2: mitofusin 2; MYH1/MHC-I: myosin, heavy polypeptide 1, skeletal muscle, adult; OCR: oxygen consumption rate; OPA1: OPA1, mitochondrial dynamin like GTPase; PINK1: PTEN induced putative kinase 1; PPARGC1A/PGC-1α: peroxisome proliferative activated receptor, gamma, coactivator 1 alpha; PRKN/PARKIN: parkin RBR E3 ubiquitin protein ligase; PTGS2/COX2: prostaglandin-endoperoxide synthase 2; RFP: red fluorescent protein; RT-qPCR: real-time quantitative PCR; SQSTM1/p62: sequestosome 1; TFAM: transcription factor A, mitochondrial; TOMM20: translocase of outer mitochondrial membrane 20; VDAC: voltage-dependent anion channel.

Thrombopoietic effects of CCAAT/enhancer-binding protein ß on the early-stage differentiation of megakaryocytes.

CCAAT/enhancer-binding protein ß (C/EBPß) is a transcription factor that is involved in adipocytic and monocytic differentiation. However, the physiological role of C/EBPß in megakaryocytes (MKs) is not clear. In this study, we investigated the effects of C/EBPß on the early-stage differentiation of MKs, and explored the potential mechanisms of action. We established a cytosine arabinoside-induced thrombocytopenia mouse model using C57BL/6 mice. In the thrombocytopenia mice, the platelet count was found to be decreased, and the mRNA and protein expression levels of C/EBPß in MKs were also reduced. Furthermore, the maturation of Dami (MKs cell line) cells was induced by phorbol 12-myristate 13-acetate. When C/EBPß was silenced in Dami cells by transfection using C/EBPß-small interfering RNA, the expression of MKs-specific markers CD41 and CD62P, was dramatically decreased, resulting in morphological changes and differentiation retardation in low ploidy, which were evaluated using flow cytometry, real-time polymerase chain reaction, western blot, and confocal microscopy. The mitogen activated protein kinase-extracellular signal-regulated kinase signaling pathway was found to be required for the differentiation of MKs; knockdown of C/EBPß in MEK/ERK1/2 pathway attenuated MKs differentiation. Overexpression of C/EBPß in MEK/ERK1/2 pathway inhibited by U0126 did not promote MKs differentiation. To the best of our knowledge, C/EBPß plays an important role in MKs differentiation and polyploidy cell cycle control. Taken together, C/EBPß may have thrombopoietic effects in the differentiation of MKs, and may assist in the development of treatments for various disorders.

Overexpression of Kininogen-1 aggravates oxidative stress and mitochondrial dysfunction in DOX-induced cardiotoxicity.

BACKGROUND: Doxorubicin (DOX) is a widely used cancer chemotherapeutic drug with cardiotoxicity effect limiting its clinical use. DOX induced cardiotoxicity is mediated by oxidative stress and mitochondrial damage. Kininogen-1(KNG1) is an important pro-inflammatory and pro-oxidant factor, and studies have found that it can aggravate lung and brain damage. However, it has not been known in terms of cardiotoxicity. Therefore, the purpose of this study is to understand the mechanism of KNG1 in DOX-induced heart injury. METHODS: C57 mice were selected for intraperitoneal injection of DOX. The model was successfully established, and fresh ventricular tissues were isolated from the ctrl group and the DOX group for mass spectrometry analysis to screen for differentially expressed proteins. Nuclear Factor-Like 2 (Nrf2), Heme Oxygenase 1 (HO-1), 4-Hydroxynonenal (4-HNE) were used to evaluate oxidative stress level, Cytochrome C Oxidase Subunit 4 (COX4) was used to evaluate mitochondria function. Mitochondrial inner membrane potential (ΔΨm) was monitored with JC-1 fluorescence. RESULTS: KNG1 was identified as a core gene which was highly expressed in the DOX myocardial injury model. Following this, an overexpression adenovirus was constructed, and KNG1 was overexpressed in vivo (mice) and in vitro (neonatal mouse cardiomyocytes (NMCMs)). It was found that overexpression of KNG1 can aggravate heart oxidative stress and mitochondrial damage. Besides, a knockdown KNG1 model was constructed, and the low expression of KNG1 was performed in cytology. It was found that knockdown of KNG1 can improve cardiomyocyte oxidative stress and mitochondrial damage caused by DOX. Nrf2 is an important antioxidant factor. Further, following KNG1 knock down, Nrf2 was also knocked down, and found that its cardiomyocyte protective effect was weakened. CONCLUSION: The overexpression of KNG1 aggravates the oxidative stress and mitochondrial damage of the heart in vivo and in vitro, which might play a role by regulating Nrf2, providing a therapeutic target for DOX-induced cardiotoxicity.

Circulating Soluble ST2 Predicts All-Cause Mortality in Severe Heart Failure Patients with an Implantable Cardioverter Defibrillator.

BACKGROUND: Heart failure (HF) is the terminal stage of all cardiovascular events. Although implantable cardioverter defibrillator (ICD) therapies have reduced mortality among the high-risk HF population, it is necessary to determine whether certain factors can predict mortality even after cardiac device implantation. Growth stimulation expressed gene 2 (ST2) is an emerging biomarker for HF patient stratification in different clinical settings. AIMS: This study aimed to investigate the relationship between baseline soluble ST2 (sST2) levels in serum and the clinical outcomes of high-risk HF patients with device implantation. METHODS: Between January 2017 and August 2018, we prospectively recruited consecutive patients implanted with an ICD for heart failure, with LVEF ≤35% as recommended, and analyzed the basic characteristics, baseline serum sST2, and NT-proBNP levels, with at least 1-year follow-up. All-cause mortality was the primary endpoint. RESULTS: During a 643-day follow-up, all-cause mortality occurred in 16 of 150 patients (10.67%). Incidence of all-cause mortality increased significantly in patients with sST2 levels above 34.98846 ng/ml (16.00% vs. 5.33%, P = 0.034). After adjusting the model (age, gender, device implantation, prevention of sudden death, LVEDD, LVEF, WBC and CLBBB, hsTNT, etiology, and eGFR) and the model combined with NT-proBNP, the risk of all-cause death was increased by 2.5% and 1.9%, respectively, per ng/ml of sST2. The best sST2 cutoff for predicting all-cause death was 43.42671 ng/ml (area under the curve: 0.72, sensitive: 0.69, and specificity: 0.69). Compared to patients with sST2 levels below 43.42671 ng/ml, the risk of all-cause mortality was higher in those with values above the threshold (5.1% vs. 21.2%, P = 0.002). ST2 level ≥43.42671 ng/ml was an independent predictor of all-cause mortality (HR: 3.30 [95% CI 1.02-10.67]). Age (HR: 1.06 [95% CI: 1.01-1.12]) and increased NT-proBNP per 100 (HR: 1.02 [95% CI: 1.01-1.03]) were also associated with all-cause mortality in ICD patients. CONCLUSIONS: sST2 level was associated with risk of all-cause mortality, and a threshold of 43.43 ng/ml showed good distinguishing performance to predict all-cause mortality in patients with severe heart failure, recommended for ICD implantation. Patients with sST2 levels more than 43.42671 ng/ml even after ICD implantation should therefore be monitored carefully.

Orosomucoid 1 Attenuates Doxorubicin-Induced Oxidative Stress and Apoptosis in Cardiomyocytes via Nrf2 Signaling.

Doxorubicin (DOX) is an effective anticancer drug, but its therapeutic use is limited by its cardiotoxicity. The principal mechanisms of DOX-induced cardiotoxicity are oxidative stress and apoptosis in cardiomyocytes. Orosomucoid 1 (ORM1), an acute-phase protein, plays important roles in inflammation and ischemic stroke; however, the roles and mechanisms of ORM1 in DOX-induced cardiotoxicity remain unknown. Therefore, in the present study, we aimed to investigate the function of ORM1 in cardiomyocytes experiencing DOX-induced oxidative stress and apoptosis. A DOX-induced cardiotoxicity animal model was established in C57BL/6 mice by administering an intraperitoneal injection of DOX (20 mg/kg), and the control group was intraperitoneally injected with the same volume of sterilized saline. The effects were assessed after 7 d. Additionally, H9c2 cells were stimulated with DOX (10 µM) for 24 h. The results showed decreased ORM1 and increased oxidative stress and apoptosis after DOX stimulation in vivo and in vitro. ORM1 overexpression significantly reduced DOX-induced oxidative stress and apoptosis in H9c2 cells. ORM1 significantly increased the expression of nuclear factor-like 2 (Nrf2) and its downstream protein heme oxygenase 1 (HO-1) and reduced the expression of the lipid peroxidation end product 4-hydroxynonenal (4-HNE) and the level of cleaved caspase-3. In addition, Nrf2 silencing reversed the effects of ORM1 on DOX-induced oxidative stress and apoptosis in cardiomyocytes. In conclusion, ORM1 inhibited DOX-induced oxidative stress and apoptosis in cardiomyocytes by regulating the Nrf2/HO-1 pathway, which might provide a new treatment strategy for DOX-induced cardiotoxicity.

Clinical efficacy of anesthesia with intensive care nursing in attenuating postoperative complications in patients with breast cancer.

OBJECTIVE: Complications frequently occur in patients with breast cancer after surgery. Anesthesia nursing plays an important role in decreasing complications for such patients. Thus, this study investigated the effects of anesthesia with intensive care nursing (AICN) on complication rates in patients with breast cancer after surgery. METHODS: Eighty-two patients with breast cancer were recruited in this study. Complications were compared between the anesthesia with usual nursing care (AUCN) and AICN groups. RESULTS: The results demonstrated that AICN decreased the rates of incision infection, drug extravasation, and catheter exposure, as well as pain and inflammation scores, compared with the findings in the AUCN group. AICN improved the time to orientation and decreased the incidence of nausea, anxiety, depression, and vomiting versus AUCN. In addition, AICN shortened the time to awakening after anesthesia compared with the effects of AUCN. Furthermore, AICN shortened hospital stay and increased survival rates. Notably, AICN improved health-related quality of life as measured using the EORTC QLQ-C30 questionnaire. CONCLUSION: AICN provided more benefits and better postoperative outcomes than AUCN, suggesting its utility for minimizing complications in patients with breast cancer after surgery.

Recombinant Cellular Repressor of E1A-Stimulated Genes Protects against Renal Fibrosis in Dahl Salt-Sensitive Rats.

BACKGROUND: Human cellular repressor of E1A-stimulated genes (CREG) is a secreted glycoprotein that attenuates angiotensin II-induced hypertension, alleviates myocardial fibrosis, and improves heart function. However, the role of CREG in high-salt (HS) diet-induced hypertensive nephropathy is unclear. METHODS: To determine the effects and molecular mechanisms of CREG in HS diet-induced hypertensive nephropathy, we established a hypertensive nephropathy animal model in Dahl salt-sensitive (SS) rats fed a HS diet (8% NaCl, n = 20) for 8 weeks. At week 4 of HS loading, these rats were administered recombinant CREG (reCREG; 35 µg/kg·day, n = 5) and saline (n = 5) via subcutaneously implanted pumps and were also administered the vasodilator hydralazine (20 mg/kg·day, n = 5) in drinking water. We used hematoxylin and eosin staining, Masson's trichrome staining, immunohistochemical labeling, western blotting, RT-PCR, and Tunel staining to determine the signaling pathways of CREG in HS diet-induced hypertensive nephropathy. RESULTS: After 8 weeks of HS intake, the Dahl SS rats developed renal dysfunction and severe renal fibrosis associated with reductions of 78 and 67% in CREG expression, respectively, at both mRNA and protein levels in the kidney. Administration of reCREG improved renal function and relieved renal fibrosis. Administration of CREG also inhibited monocyte infiltration and reduced apoptosis in the kidney cells. CREG overexpression upregulated forkhead box P1 expression and inhibited the transforming growth factor-ß1 signaling pathway. CONCLUSION: Our study shows that CREG protected the kidney against HS-diet-induced renal damage and provides new insights into the mechanisms underlying kidney injury.

Luteolin attenuates sepsis­induced myocardial injury by enhancing autophagy in mice.

Sepsis­induced cardiomyopathy (SIC) is a complication of severe sepsis and septic shock characterized by an invertible myocardial depression. This study sought to explore the potential effects and mechanism of luteolin, a flavonoid polyphenolic compound, in lipopolysaccharide (LPS)­induced myocardial injury. Experimental mice were randomly allocated into 3 groups (25 mice in each group): The control group (NC), the LPS group (LPS) and the LPS + luteolin group (LPS + Lut). Before the SIC model was induced, luteolin was dissolved in DMSO and injected intraperitoneally for 10 days into LPS + Lut group mice. NC group and LPS group mice received an equal volume of DMSO for 10 days. On day 11, the animal model of sepsis­induced cardiac dysfunction was induced by intraperitoneal injection of LPS. A total of 12 h after LPS injection, measurements and comparisons were made among the groups. Luteolin administration improved cardiac function, attenuated the inflammatory response, alleviated mitochondrial injury, decreased oxidative stress, inhibited cardiac apoptosis and enhanced autophagy. In addition, luteolin significantly decreased the phosphorylation of AMP­activated protein kinase (AMPK) in septic heart tissue. The protective effect of luteolin was abolished by 3­methyladenine (an autophagy inhibitor) and dorsomorphin (compound C, an AMPK inhibitor), as evidenced by decreased autophagic activity, destabilized mitochondrial membrane potential and increased apoptosis in LPS­treated cardiomyocytes, but was mimicked by 5­aminoimidazole­4­carboxamide ribonucleotide (an AMPK activator), suggesting that luteolin attenuates LPS­induced myocardial injury by increasing autophagy through AMPK activation. Luteolin may be a promising therapeutic agent for treating SIC.