TREM2 macrophage promotes cardiac repair in myocardial infarction by reprogramming metabolism via SLC25A53.

Efferocytosis and metabolic reprogramming of macrophages play crucial roles in myocardial infarction (MI) repair. TREM2 has been proven to participate in phagocytosis and metabolism, but how it modulates myocardial infarction remains unclear. In this study, we showed that macrophage-specific TREM2 deficiency worsened cardiac function and impaired post-MI repair. Using RNA-seq, protein and molecular docking, and Targeted Metabolomics (LC-MS), our data demonstrated that macrophages expressing TREM2 exhibited decreased SLC25A53 transcription through the SYK-SMAD4 signaling pathway after efferocytosis, which impaired NAD+ transport into mitochondria, downregulated SLC25A53 thereby causing the breakpoint in the TCA cycle and subsequently increased itaconate production. In vitro experiments confirmed that itaconate secreted by TREM2+ macrophages inhibited cardiomyocyte apoptosis and promoted fibroblast proliferation. Conversely, overexpression of TREM2 in macrophages could improve cardiac function. In summary, our study reveals a novel role for macrophage-specific TREM2 in MI, connecting efferocytosis to immune metabolism during cardiac repair.

Endothelial TET2 regulates the white adipose browning and metabolism via fatty acid oxidation in obesity.

Obesity is a complex metabolic disorder, manifesting as excessive accumulation of body fat. Ten-Eleven Translocation-2 (TET2) has garnered significant attention in the context of obesity due to its crucial role in epigenetic regulation and metabolic homeostasis. In this study, we aimed to investigate the effect of endothelial TET2 on obesity and explore the potential mechanism. We generated endothelial cell-specific TET2 deficiency mice and investigated endothelial TET2 using transcriptomic and epigenomic analyses. We determined the downregulation of endothelial TET2 in white adipose tissues. Furthermore, we identified that endothelial TET2 loss aggravated high-fat diet-induced obesity by inhibiting vascularization and thus suppressing white adipose tissue browning. Mechanistically, endothelial TET2 modulates obesity by engaging in endothelial fatty acid oxidation and angiocrine-mediated secretion of bone morphogenetic protein 4 (BMP4), in which nuclear factor-erythroid 2-related factor 2 (NRF2) serves as a key mediator. Our study reveals that endothelial TET2 regulates white adipose tissue browning by interacting with NRF2 to facilitate fatty acid oxidation and lipolysis in adipocytes.

Recent design strategies and applications of organic fluorescent probes for food freshness detection.

Food spoilage poses a significant risk to human health, making the assessment of food freshness essential for ensuring food safety and quality. In recent years, there has been rapid progress in the development of fast detection technologies for food freshness. Among them, organic fluorescent probes have garnered significant attention in the field of food safety and sensing due to their easy functionalization, high sensitivity, and user-friendly nature. To comprehensively examine the latest advancements in organic fluorescent probes for food freshness detection, this review summarized their applications within the past five years. Initially, the fundamental detection principles of organic fluorescent probes are outlined. Subsequently, the recent research progress in utilizing organic fluorescent probes to detect various chemical indicators of freshness are discussed. Finally, the challenges and future directions for organic fluorescent probes in food freshness detection are elaborated upon. While, organic fluorescent probes have demonstrated their effectiveness in evaluating food freshness and possess great potential for practical applications, further research is still needed to enable their widespread commercial utilization. With continued advancements in synthesis and functionalization techniques, organic fluorescent probes will contribute to enhancing the efficiency of food safety detection.

IL-27 promotes cardiac fibroblast activation and aggravates cardiac remodeling post myocardial infarction.

Excessive and chronic inflammation post myocardial infarction (MI) causes cardiac fibrosis and progressive ventricular remodeling, which leads to heart failure. We previously found high levels of IL-27 in the heart and serum until day 14 in murine cardiac ischemia‒reperfusion injury models. However, whether IL-27 is involved in chronic inflammation-mediated ventricular remodeling remains unclear. In the present study, we found that MI triggered high IL-27 expression in murine cardiac macrophages. The increased expression of IL-27 in serum is correlated with cardiac dysfunction and aggravated fibrosis after MI. Furthermore, the addition of IL-27 significantly activated the JAK/STAT signaling pathway in cardiac fibroblasts (CFs). Meanwhile, IL-27 treatment promoted the proliferation, migration and extracellular matrix (ECM) production of CFs induced by angiotensin II (Ang II). Collectively, high levels of IL-27 mainly produced by cardiac macrophages post MI contribute to the activation of CFs and aggravate cardiac fibrosis.

Anti-oxidative and anti-aging effects of mannoprotein-rich yeast cell wall enzymatic hydrolysate by modulating gut microbiota and metabolites in Caenorhabditis elegans.

In this study, antioxidant and anti-aging studies were carried out by mannoprotein-rich yeast cell wall enzymatic hydrolysate (MYH) obtained by enzymatic hydrolysis of yeast cell wall through the Caenorhabditis elegans (C. elegans) model. It was found that MYH could improve the lifespan and anti-stress ability of C. elegans by increasing the activity of antioxidant enzymes such as T-SOD, GSH-PX and CAT, and reducing the levels of MDA, ROS and apoptosis. At the same time, through the verification expression of corresponding mRNA, it was found that MYH exerted antioxidant and anti-aging activities by up-regulating the translation of MTL-1, DAF-16, SKN-1 and SOD-3 mRNA, and down-regulating the translation of AGE-1 and DAF-2 mRNA. In addition, it was found that MYH could improve the composition and distribution of the gut microbiota of C. elegans, and significantly improve the level of metabolites through the sequencing of gut microbiota and untargeted metabolomic studies. It has contributed to studying the antioxidant and anti-aging activities of microorganisms such as yeast through the level of gut microbiota and metabolites and the development of related functional foods.

Protein-rich yeast extract (®fermgard) has potential antioxidant and anti-aging activities.

There existed a deficiency in the research on the nutritional activities of microbial (yeast) active substances in antioxidant and anti-aging activities, although the research objects were concentrated in animals and plants in recent years. In this study, the anti-oxidant and anti-aging activities of protein-rich yeast extract (®fermgard) (YE) were investigated through Caenorhabditis elegans (C. elegans). The results indicated that YE could improve the lifespan and anti-stress ability by up-regulating the activities of antioxidant enzymes in C. elegans. Meanwhile, the mRNA transcriptional level of daf-16, skn-1 and sod-3 was significantly up-regulated. In addition, the composition and level of the gut microbiota and metabolite were modulated. YE exerts antioxidant and anti-aging activities by regulating the expression of anti-oxidation-related mRNA, gut microbiota and metabolites in C. elegans, providing a basis for exploring the deep mechanism of YE improving health. At the same time, it provides new ideas for the development of functional foods.

Anti-Oxidative and Anti-Aging Effects of Probiotic Fermented Ginseng by Modulating Gut Microbiota and Metabolites in Caenorhabditis elegans.

Antioxidative and antiaging abilities of probiotic fermented ginseng (PG) were evaluated in Caenorhabditis elegans (C. elegans). Lifespan and effect on heat stress and acute oxidative stress in C. elegans were significantly enhanced by PG. Antioxidative enzymes such as T-SOD, GSH-PX, CAT were significantly up-regulated, and MDA, ROS and apoptosis levels were significantly down-regulated. At the same time, PG exerted antioxidant and anti-aging activities by reducing the expression of DAF-2 mRNA and increasing the expression of SKN-1 and SOD-3 mRNA in C. elegans. In addition, the mechanism of antioxidative and antiaging activities of PG was explored through gut microbiota sequencing and untargeted metabolomics. The results of gut microbiota indicated that PG could significantly improve the composition and structure of microbes in the gut of C. elegans, and the relative abundance of beneficial bacteria was up-regulated. Untargeted metabolomic results elucidated that PG modulated antioxidant and antiaging activities through neuroactive ligand-receptor interaction, Citrate cycle (TCA cycle), pyruvate metabolism, ascorbate and aldarate metabolism and D-Arginine and D-ornithine metabolism of C. elegans. These results indicated that PG had excellent antioxidant and anti-aging activities, providing research value for the development of functional foods and improvement of aging-related diseases.

Myosin light-chain 4 gene-transfer attenuates atrial fibrosis while correcting autophagic flux dysregulation.

OBJECTIVES: To determine the role of MYL4 regulation of lysosomal function and its disturbance in fibrotic atrial cardiomyopathy. BACKGROUND: We have previously demonstrated that the atrial-specific essential light chain protein MYL4 is required for atrial contractile, electrical, and structural integrity. MYL4 mutation/dysfunction leads to atrial fibrosis, standstill, and dysrhythmia. However, the underlying pathogenic mechanisms remain unclear. METHODS AND RESULTS: Rats subjected to knock-in of a pathogenic MYL4 mutant (p.E11K) developed fibrotic atrial cardiomyopathy. Proteome analysis and single-cell RNA sequencing indicate enrichment of autophagy pathways in mutant-MYL4 atrial dysfunction. Immunofluorescence and electron microscopy revealed undegraded autophagic vesicles accumulated in MYL4p.E11K rat atrium. Next, we identified that dysfunctional MYL4 protein impairs autophagy flux in vitro and in vivo. Cardiac lysosome positioning and mobility were regulated by MYL4 in cardiomyocytes, which affected lysosomal acidification and maturation of lysosomal cathepsins. We then examined the effects of MYL4 overexpression via adenoviral gene-transfer on atrial cardiomyopathy induced by MYL4 mutation: MYL4 protein overexpression attenuated atrial structural remodeling and autophagy dysfunction. CONCLUSIONS: MYL4 regulates autophagic flux in atrial cardiomyocytes via lysosomal mobility. MYL4 overexpression attenuates MYL4 p.E11K induced fibrotic atrial cardiomyopathy, while correcting autophagy and lysosomal function. These results provide a molecular basis for MYL4-mutant induced fibrotic atrial cardiomyopathy and identify a potential biological-therapy approach for the treatment of atrial fibrosis.

Extracellular traps from activated vascular smooth muscle cells drive the progression of atherosclerosis.

Extracellular DNA traps (ETs) represent an immune response by which cells release essential materials like chromatin and granular proteins. Previous studies have demonstrated that the transdifferentiation of vascular smooth muscle cells (VSMCs) plays a crucial role in atherosclerosis. This study seeks to investigate the interaction between CD68+ VSMCs and the formation of ETs and highlight its function in atherosclerosis. Here we show that ETs are inhibited, and atherosclerotic plaque formation is alleviated in male Myh11CrePad4flox/flox mice undergoing an adeno-associated-virus-8 (AAV8) mediating overexpression of proprotein convertase subtilisin/kexin type 9 mutation (PCSK9) injection and being challenged with a high-fat diet. Obvious ETs generated from CD68+ VSMCs are inhibited by Cl-amidine and DNase I in vitro. By utilizing VSMCs-lineage tracing technology and single-cell RNA sequencing (scRNA-seq), we demonstrate that the ETs from CD68+ VSMCs influence the progress of atherosclerosis by regulating the direction of VSMCs' transdifferentiation through STING-SOCS1 or TLR4 signaling pathway.

CD4+FoxP3+CD73+ regulatory T cell promotes cardiac healing post-myocardial infarction.

Rationale: Despite recent studies indicating a crucial role of ecto-5'-nucleotidase (CD73) on T cells in cardiac injury after ischemia/reperfusion, the involvement of CD73+ regulatory T cells (Tregs) in cardiac repair post-myocardial infarction (MI) remains unclear. We sought to investigate the contribution of CD73 on Tregs to the resolution of cardiac inflammation and remodeling after MI. Methods: Cardiac function, tissue injury, Tregs percentage in injured hearts, and purinergic signaling changes in cardiac FoxP3+ Tregs were analyzed after permanent descending coronary artery ligation. CD73 knockout Tregs were used to determine the function of CD73 on Tregs. Peripheral blood mononuclear cells (PBMCs) from acute myocardial infarction (AMI) patients and matched non-MI subjects were assessed via flow cytometry. Results: Cardiac Tregs exhibited distinction of purinergic signaling post MI with dramatically high level of CD73 compared to the sham Tregs. CD73 deficiency decreased the tissue tropism, and impaired the immunosuppressive and protective function of Tregs in cardiac healing. Administration of low-dose of IL-2/anti-IL-2 complex resulted in FoxP3+CD73+Tregs expansion in the heart and contributed to the recovery of cardiac function. CD73 derived from FoxP3+Tregs could bind to FoxP3- effector T-cells and inhibit the production of multiple inflammatory cytokines. In AMI patients, CD73 expressions on both CD4+ cells and FoxP3+Tregs decreased in PBMCs. Moreover, CD73 expressions on CD4+ T cells were negatively correlated with the levels of NT pro-BNP and myocardial zymogram in serum. Conclusions: Our findings indicated the importance of FoxP3+CD73+Tregs in inflammation resolution and cardiac healing post-MI.

Effect and Mechanism of LRP6 on Cardiac Myocyte Ferroptosis in Myocardial Infarction.

BACKGROUND: This study was aimed at exploring the biological function and molecular mechanism of ferroptosis of LRP6 modulation in cardiomyocytes of myocardial infarction (MI). METHOD: We established the ferroptosis model of MI in vivo and in vitro and constructed the modulation network of circRNA-miRNA-LRP6 by bioinformatics analysis; then, we focused on exploring the regulatory relationship of LRP6 and its upstream genes circRNA1615 and miR-152-3p in the RIP experiments and the double luciferase reporter gene assay. Also, we tested the LRP6-mediated autophagy-related ferroptosis in MI. RESULTS: Ferroptosis was found in cardiomyocytes of MI, and ferroptosis inhibitor Ferrostatin-1 (Fer-1) could improve the pathological process of MI. LRP6 was involved in the process of ferroptosis in cardiomyocytes, and LRP6 deletion regulated ferroptosis in cardiomyocytes through autophagy. Screening and identification of the upstream gene circRNA1615 would target LRP6. circRNA1615 inhibited ferroptosis in cardiomyocytes, and circRNA1615 could regulate the expression of LRP6 through sponge adsorption of miR-152-3p, prevent LRP6-mediated autophagy-related ferroptosis in cardiomyocytes, and finally control the pathological process of MI. CONCLUSIONS: circRNA1615 inhibits ferroptosis via modulation of autophagy by the miRNA152-3p/LRP6 molecular axis in cardiomyocytes of myocardial infarction.

The Association of Left Atrial Appendage Morphology to Atrial Fibrillation Recurrence After Radiofrequency Ablation.

Objective: The probability of late recurrent atrial fibrillation (AF) after radiofrequency ablation (RFA) has not yet been fully clarified. This study aims to study the association of left atrial appendage (LAA) morphology with AF recurrence after RFA. Methods: We retrospectively enrolled 84 patients (24 patients had persistent AF, 60 patients had paroxysmal AF) who underwent RFA in Shanghai East Hospital from June 2014 to May 2018. The mean follow-up of these patients was 618.6 days. According to preoperative transesophageal echocardiography (TEE), the morphology feature of LAA was classified and evaluated by two classification methods. The first method was divided into chicken-wing, windsock, cactus, and cauliflower, and the second method was divided into one lobe, two lobes, and multiple lobes. The correlation between morphological feature of LAA and the recurrence rate of AF after RFA was analyzed. Results: During follow-up, 12 patients (50%) and 10 patients (16.7%) had AF recurrence in persistent and paroxysmal AF, respectively. The LAA morphology was associated with the recurrence of AF after RFA with the chicken-wing highest recurrence risk (68.2%). The structure type of LAA was also related to the AF recurrence rate (p < 0.01). Compared with one lobe and multiple lobes, two lobes (recurrence, 47.6%) were more likely associated with the recurrence of AF (p < 0.02). Logistic regression analysis showed that the chicken-wing group had a higher risk of recurrence after RFA (OR = 8.13, p = 0.004), and the windsock group had a lower risk of recurrence (OR = 0.17, p = 0.002). Conclusion: The morphological feature of LAA is related to the recurrence risk of AF after RFA. LAA morphology assessment can predict the risk of AF recurrence.

Hypolipidemic properties of Chlorella pyrenoidosa organic acids via AMPK/HMGCR/SREBP-1c pathway in vivo.

The aim of this study was to explore the effects and mechanisms of 95% ethanol extract of Chlorella pyrenoidosa (CPE95) on lipid metabolism in hyperlipidemic rats. For the sake of chemical composition analysis of CPE95, liquid chromatography-mass spectrometry (LC-MS) was used for determination. After treatment with CPE95, serum high-density lipoprotein cholesterol content of the hyperlipidemic rats was increased, while the contents of cholesterol, triglyceride, and low-density lipoprotein cholesterol were decreased strikingly. Moreover, the result of histopathology analysis showed that the accumulation and fatty deformation of the livers were relieved. Real-time quantitative PCR and Western blotting were used to determine the expression levels of lipid metabolism-related genes. The gene expression level of adenosine 5'-monophosphate-activated protein kinase was descended, and expressions of sterol regulatory element-binding protein-1c, acetyl-CoA carboxylase, and 3-hydroxy-3-methylglutaryl coenzyme A reductase were all downregulated in the CPE95-treated rats. It suggested that CPE95 may effectively improve the hyperlipidemia in rats and would be potential for functional food component to reduce blood lipid.

Co-loading antioxidant N-acetylcysteine attenuates cytotoxicity of iron oxide nanoparticles in hypoxia/reoxygenation cardiomyocytes.

PURPOSE: Myocardial delivery of magnetic iron oxide nanoparticles (MNPs) might produce iron overload-induced myocardial injury, and the oxidative stress was regarded as the main mechanism. Therefore, we speculated antioxidant modification might be a reasonable strategy to mitigate the toxicity of MNPs. METHODS AND RESULTS: Antioxidant N-acetylcysteine (NAC) was loaded into magnetic mesoporous silica coated Fe3O4 nanoparticles. Neonatal rat hypoxia/reoxygenation (H/R) cardiomyocytes were incubated with nanoparticles for 24 hrs. NAC can effectively mitigate iron-induced oxidative injury of cardiomyocytes, evidenced by reduced production of MDA, 8-iso-PGF2α, and 8-OHDG and maintained concentrations of SOD, CAT, GSH-Px, and GSH in ELISA and biochemical tests; downregulated expression of CHOP, GRP78, p62, and LC3-II proteins in Western Blot, and less cardiomyocytes apoptosis in flow cytometric analysis. CONCLUSIONS: NAC modifying could suppress the toxic effects of Fe3O4 nanoparticles in H/R cardiomyocytes model in vitro, indicating a promising strategy to improve the safety of iron oxide nanoparticles.

Dynamic Profile of CD4+ T-Cell-Associated Cytokines/Chemokines following Murine Myocardial Infarction/Reperfusion.

CD4+ T-cells play crucial roles in the injured heart. However, the way in which different CD4+ T subtypes function in the myocardial infarction/reperfusion (MI/R) heart is still poorly understood. We aimed to detect the dynamic profile of distinct CD4+ subpopulation-associated cytokines/chemokines by relying on a closed-chest acute murine MI/R model. The protein levels of 26 CD4+ T-cell-associated cytokines/chemokines were detected in the heart tissues and serum of mice at day 7 and day 14 post-MI/R or sham surgery. The mRNA levels of IL-4, IL-6, IL-13, IL-27, MIP-1ß, MCP-3, and GRO-α were measured in blood mononuclear cells. The protein levels of IL-4, IL-6, IL-13, IL-27, MIP-1ß, MCP-3, and GRO-α increased in both injured heart tissues and serum, while IFN-γ, IL-12P70, IL-2, IL-1ß, IL-18, TNF-α, IL-5, IL-9, IL-17A, IL-23, IL-10, eotaxin, MIP-1α, RANTES, MCP-1, and MIP-2 increased only in MI/R heart tissues in the day 7 and day 14 groups compared to the sham group. In serum, the IFN-γ, IL-23, and IL-10 levels were downregulated in the MI/R model at both day 7 and day 14 compared to the sham. Compared with the protein expressions in injured heart tissues at day 7, IFN-γ, IL-12P70, IL-2, IL-18, TNF-α, IL-6, IL-4, IL-5, IL-9, IL-17A, IL-23, IL-27, IL-10, eotaxin, IP-10, RANTES, MCP-1, MCP-3, and GRO-α were reduced, while IL-1ß and MIP-2 were elevated at day 14. IL-13 and MIP-1ß showed higher levels in the MI/R serum at day 14 than at day 7. mRNA levels of IL-4, IL-6, IL-13, and IL-27 were increased in the day 7 group compared to the sham, while MIP-1ß, MCP-3, and GRO-α mRNA levels showed no significant difference between the MI/R and sham groups in blood mononuclear cells. Multiple CD4+ T-cell-associated cytokines/chemokines were upregulated in the MI/R hearts at the chronic stage. These results provided important evidence necessary for developing future immunomodulatory therapies after MI/R.

The antiviral activity of arctigenin in traditional Chinese medicine on porcine circovirus type 2.

Arctigenin (ACT) is a phenylpropanoid dibenzylbutyrolactone lignan extracted from the traditional herb Arctium lappa L. (Compositae) with anti-viral and anti-inflammatory effects. Here, we investigated the antiviral activity of ACT found in traditional Chinese medicine on porcine circovirus type 2 (PCV2) in vitro and in vivo. Results showed that dosing of 15.6-62.5µg/mL ACT could significantly inhibit the PCV2 proliferation in PK-15 cells (P<0.01). Dosing of 62.5µg/mL ACT 0, 4 or 8h after challenge inoculation significantly inhibited the proliferation of 1MOI and 10MOI in PK-15 cells (P<0.01), and the inhibitory effect of ACT dosing 4h or 8h post-inoculation was greater than 0h after dosing (P<0.01). In vivo test with mice challenge against PCV2 infection demonstrated that intraperitoneal injection of 200µg/kg ACT significantly inhibited PCV2 proliferation in the lungs, spleens and inguinal lymph nodes, with an effect similar to ribavirin, demonstrating the effectiveness of ACT as an antiviral agent against PCV2 in vitro and in vivo. This compound, therefore, may have the potential to serve as a drug for protection of pigs against the infection of PCV2.

Extended GTST-MLD for aerospace system safety analysis.

The hazards caused by complex interactions in the aerospace system have become a problem that urgently needs to be settled. This article introduces a method for aerospace system hazard interaction identification based on extended GTST-MLD (goal tree-success tree-master logic diagram) during the design stage. GTST-MLD is a functional modeling framework with a simple architecture. Ontology is used to extend the ability of system interaction description in GTST-MLD by adding the system design knowledge and the past accident experience. From the level of functionality and equipment, respectively, this approach can help the technician detect potential hazard interactions. Finally, a case is used to show the method.