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1.
J Nanobiotechnology ; 22(1): 132, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532378

RESUMO

BACKGROUND: Cardiovascular diseases (CVDs) have the highest mortality worldwide. Human pluripotent stem cells (hPSCs) and their cardiomyocyte derivatives (hPSC-CMs) offer a valuable resource for disease modeling, pharmacological screening, and regenerative therapy. While most CVDs are linked to significant over-production of reactive oxygen species (ROS), the effects of current antioxidants targeting excessive ROS are limited. Nanotechnology is a powerful tool to develop antioxidants with improved selectivity, solubility, and bioavailability to prevent or treat various diseases related to oxidative stress. Cerium oxide nanozymes (CeONZs) can effectively scavenge excessive ROS by mimicking the activity of endogenous antioxidant enzymes. This study aimed to assess the nanotoxicity of CeONZs and their potential antioxidant benefits in stressed human embryonic stem cells (hESCs) and their derived cardiomyocytes (hESC-CMs). RESULTS: CeONZs demonstrated reliable nanosafety and biocompatibility in hESCs and hESC-CMs within a broad range of concentrations. CeONZs exhibited protective effects on the cell viability of hESCs and hESC-CMs by alleviating excessive ROS-induced oxidative stress. Moreover, CeONZs protected hESC-CMs from doxorubicin (DOX)-induced cardiotoxicity and partially ameliorated the insults from DOX in neonatal rat cardiomyocytes (NRCMs). Furthermore, during hESCs culture, CeONZs were found to reduce ROS, decrease apoptosis, and enhance cell survival without affecting their self-renewal and differentiation potential. CONCLUSIONS: CeONZs displayed good safety and biocompatibility, as well as enhanced the cell viability of hESCs and hESC-CMs by shielding them from oxidative damage. These promising results suggest that CeONZs may be crucial, as a safe nanoantioxidant, to potentially improve the therapeutic efficacy of CVDs and be incorporated into regenerative medicine.


Assuntos
Cério , Miócitos Cardíacos , Células-Tronco Pluripotentes , Humanos , Ratos , Animais , Espécies Reativas de Oxigênio/metabolismo , Estresse Oxidativo , Diferenciação Celular , Antioxidantes/farmacologia , Doxorrubicina/farmacologia
2.
Mar Pollut Bull ; 201: 116188, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38402697

RESUMO

In this study, the ecological risk assessment of PAHs pollution, the existing S-T model was improved and applied to this PAHs pollution assessment in surface sediment in Lake Chaohu. The potential sources and contributions of PAHs in the surface sediment were estimated by molecular diagnostic ratio (MDR) and positive matrix factorization (PMF). The results showed that the average concentration of 16 priority PAHs in the surface sediment was 718.16 ng/g in 2009 and 334.67 ng/g in 2020. In 2020, PAHs concentration has decreased compared to 2009 and the dominant composition has changed from high- to low-molecular-weight PAHs. The estimated PAHs mass inventory of the top 2 cm surface sediment was 2712 tons in 2009 and 1263 tons in 2020. Ecosystem risk assessment by improved S-T models suggested that the overall ecosystem risk of the studied regions was acceptable.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Hidrocarbonetos Policíclicos Aromáticos/análise , Ecossistema , Monitoramento Ambiental , Lagos/análise , Sedimentos Geológicos , Poluentes Químicos da Água/análise , Medição de Risco , China
3.
Stem Cell Res Ther ; 15(1): 31, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317221

RESUMO

BACKGROUND: Transcription factors HAND1 and HAND2 (HAND1/2) play significant roles in cardiac organogenesis. Abnormal expression and deficiency of HAND1/2 result in severe cardiac defects. However, the function and mechanism of HAND1/2 in regulating human early cardiac lineage commitment and differentiation are still unclear. METHODS: With NKX2.5eGFP H9 human embryonic stem cells (hESCs), we established single and double knockout cell lines for HAND1 and HAND2, respectively, whose cardiomyocyte differentiation efficiency could be monitored by assessing NKX2.5-eGFP+ cells with flow cytometry. The expression of specific markers for heart fields and cardiomyocyte subtypes was examined by quantitative PCR, western blot and immunofluorescence staining. Microelectrode array and whole-cell patch clamp were performed to determine the electrophysiological characteristics of differentiated cardiomyocytes. The transcriptomic changes of HAND knockout cells were revealed by RNA sequencing. The HAND1/2 target genes were identified and validated experimentally by integrating with HAND1/2 chromatin immunoprecipitation sequencing data. RESULTS: Either HAND1 or HAND2 knockout did not affect the cardiomyocyte differentiation kinetics, whereas depletion of HAND1/2 resulted in delayed differentiation onset. HAND1 knockout biased cardiac mesoderm toward second heart field progenitors at the expense of first heart field progenitors, leading to increased expression of atrial and outflow tract cardiomyocyte markers, which was further confirmed by the appearance of atrial-like action potentials. By contrast, HAND2 knockout cardiomyocytes had reduced expression of atrial cardiomyocyte markers and displayed ventricular-like action potentials. HAND1/2-deficient hESCs were more inclined to second heart field lineage and its derived cardiomyocytes with atrial-like action potentials than HAND1 single knockout during differentiation. Further mechanistic investigations suggested TBX5 as one of the downstream targets of HAND1/2, whose overexpression partially restored the abnormal cardiomyocyte differentiation in HAND1/2-deficient hESCs. CONCLUSIONS: HAND1/2 have specific and redundant roles in cardiac lineage commitment and differentiation. These findings not only reveal the essential function of HAND1/2 in cardiac organogenesis, but also provide important information on the pathogenesis of HAND1/2 deficiency-related congenital heart diseases, which could potentially lead to new therapeutic strategies.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Células-Tronco Embrionárias Humanas , Humanos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular/genética , Miócitos Cardíacos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo
4.
Circ Res ; 134(3): 290-306, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38197258

RESUMO

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the most prevalent monogenic heart disorder. However, the pathogenesis of HCM, especially its nongenetic mechanisms, remains largely unclear. Transcription factors are known to be involved in various biological processes including cell growth. We hypothesized that SP1 (specificity protein 1), the first purified TF in mammals, plays a role in the cardiomyocyte growth and cardiac hypertrophy of HCM. METHODS: Cardiac-specific conditional knockout of Sp1 mice were constructed to investigate the role of SP1 in the heart. The echocardiography, histochemical experiment, and transmission electron microscope were performed to analyze the cardiac phenotypes of cardiac-specific conditional knockout of Sp1 mice. RNA sequencing, chromatin immunoprecipitation sequencing, and adeno-associated virus experiments in vivo were performed to explore the downstream molecules of SP1. To examine the therapeutic effect of SP1 on HCM, an SP1 overexpression vector was constructed and injected into the mutant allele of Myh6 R404Q/+ (Myh6 c. 1211C>T) HCM mice. The human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) from a patient with HCM were used to detect the potential therapeutic effects of SP1 in human HCM. RESULTS: The cardiac-specific conditional knockout of Sp1 mice developed a typical HCM phenotype, displaying overt myocardial hypertrophy, interstitial fibrosis, and disordered myofilament. In addition, Sp1 knockdown dramatically increased the cell area of hiPSC-CMs and caused intracellular myofibrillar disorganization, which was similar to the hypertrophic cardiomyocytes of HCM. Mechanistically, Tuft1 was identified as the key target gene of SP1. The hypertrophic phenotypes induced by Sp1 knockdown in both hiPSC-CMs and mice could be rescued by TUFT1 (tuftelin 1) overexpression. Furthermore, SP1 overexpression suppressed the development of HCM in the mutant allele of Myh6 R404Q/+ mice and also reversed the hypertrophic phenotype of HCM hiPSC-CMs. CONCLUSIONS: Our study demonstrates that SP1 deficiency leads to HCM. SP1 overexpression exhibits significant therapeutic effects on both HCM mice and HCM hiPSC-CMs, suggesting that SP1 could be a potential intervention target for HCM.


Assuntos
Cardiomiopatia Hipertrófica , Células-Tronco Pluripotentes Induzidas , Humanos , Camundongos , Animais , Células-Tronco Pluripotentes Induzidas/metabolismo , Cardiomiopatia Hipertrófica/metabolismo , Miofibrilas/metabolismo , Miócitos Cardíacos/metabolismo , Cardiomegalia/metabolismo , Fatores de Transcrição/metabolismo , Mamíferos
5.
Inorg Chem ; 63(1): 870-880, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38117690

RESUMO

Solar-powered photocatalytic conversion of CO2 to hydrocarbon fuels represents an emerging approach to solving the greenhouse effect. However, low charge separation efficiency, deficiency of surface catalytic active sites, and sluggish charge-transfer kinetics, together with the complicated reaction pathway, concurrently hinder the CO2 reduction. Herein, we show the rational construction of transition metal chalcogenides (TMCs) heterostructure CO2 reduction photosystems, wherein the TMC substrate is tightly integrated with amorphous oxygen-containing cobalt sulfide (CoSOH) by a solid non-conjugated polymer, i.e., poly(vinyl alcohol) (PVA), to customize the unidirectional charge-transfer pathway. In this well-defined multilayered nanoarchitecture, the PVA interim layer intercalated between TMCs and CoSOH acts as a hole-relaying mediator and meanwhile boosts CO2 adsorption capacity, while CoSOH functions as a terminal hole-collecting reservoir, stimulating the charge transport kinetics and boosting the charge separation over TMCs. This peculiar interface configuration and charge transport characteristics endow TMC/PVA/CoSOH heterostructures with significantly enhanced visible-light-driven photoactivity and CO2 conversion. Based on the intermediates probed during the photocatalytic CO2 reduction reaction, the photocatalytic mechanism was determined. Our work would inspire sparkling ideas to mediate the charge transfer over semiconductor for solar carbon neutral conversion.

6.
Inorg Chem ; 62(41): 16965-16973, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37794771

RESUMO

Atomically precise alloy nanoclusters (NCs) inherit the advantages of homometal NC counterparts such as atomic stacking fashion, quantum confinement effect, and enriched catalytic active sites and simultaneously possess the advantageous physicochemical properties such as significantly enhanced photostability, ideal photosensitization efficiency, and favorable energy band structure. Nevertheless, elucidation of the roles of alloy NCs and alloy nanocrystals (NYs) in boosting solar water oxidation has so far not yet been reported owing to the deficiency of applicable alloy NC photosystems. Herein, utilizing the generic thermal-induced self-transformation of alloy NCs to alloy NYs, we comprehensively explore the photosensitization properties of glutathione (GSH)-capped alloy NCs (AgxAu1-x@GSH and CuxAu1-x@GSH) and the corresponding alloy NY (AgAu and CuAu) counterparts in solar water oxidation reaction. The results imply that photoelectrons of alloy NCs surpass the hot electrons over plasmonic alloy NYs in stimulating the PEC water oxidation reaction. The photoelectrons of alloy NCs demonstrate lower interfacial charge-transfer resistance, longer carrier lifetime, and a more enhanced photosensitization effect with respect to the plasmonic alloy NYs, contributing to the significantly boosted photoelectrochemical water oxidation activities. Moreover, we found that our result is universal.

7.
Inorg Chem ; 62(45): 18649-18659, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37903426

RESUMO

Transition-metal chalcogenide quantum dots (TMC QDs) show great promise in artificial photosynthesis for excellent light-harvesting capability. Nonetheless, TMC QDs have limitations of ultrafast charge recombination rate, sluggish carrier migration kinetics, and generic photocorrosion, retarding their widespread applications. To solve these obstacles, herein, we demonstrate the stimulation of charge migration over TMC QDs with the aid of nonconjugated insulating polymer and graphene (GR) for a versatile photoredox selective organic transformation. To this end, an ultrathin insulating polymer layer, i.e., poly(allylamine hydrochloride) (PAH), grafted on the GR framework, is electrostatically intercalated at the interface of TMCs QDs and the GR framework via a self-assembly for constructing TMC QDs/PAH/GR three-dimensional spatially multilayered heterostructures. In this well-defined nanoarchitecture, TMC QDs function as a light-harvesting antenna, GR as a terminal electron reservoir, and PAH as an intermediate interfacial charge relay mediator. We ascertain that the ultrathin PAH interim layer unexpectedly fosters the photoelectron migration from TMCs QDs to the GR framework in a tunable fashion, boosting the charge separation of TMCs QDs and resulting in significantly improved photoactivities toward anaerobic reduction of aromatic nitro compounds to amino derivatives and oxidation of alcohols to aldehydes under visible light. Photoredox catalysis mechanisms of such TMC QDs/PAH/GR photosystems are elucidated, and the active species in these photoredox organic conversion reactions are comprehensively determined. Our work would open new frontiers to finely modulate the charge transport of TMCs QDs via nonconjugated insulating polymers for solar energy conversion.

8.
NPJ Regen Med ; 8(1): 41, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37537178

RESUMO

A genetic system, ProTracer, has been recently developed to record cell proliferation in vivo. However, the ProTracer is initiated by an infrequently used recombinase Dre, which limits its broad application for functional studies employing floxed gene alleles. Here we generated Cre-activated functional ProTracer (fProTracer) mice, which enable simultaneous recording of cell proliferation and tissue-specific gene deletion, facilitating broad functional analysis of cell proliferation by any Cre driver.

9.
Nat Commun ; 14(1): 1796, 2023 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-37002228

RESUMO

The growth and maturation of the ventricular chamber require spatiotemporally precise synergy between diverse cell types. Alternative splicing deeply affects the processes. However, the functional properties of alternative splicing in cardiac development are largely unknown. Our study reveals that an alternative splicing factor polypyrimidine tract-binding protein 1 (PTBP1) plays a key role in ventricular chamber morphogenesis. During heart development, PTBP1 colocalizes with endothelial cells but is almost undetectable in cardiomyocytes. The endothelial-specific knockout of Ptbp1, in either endocardial cells or pan-endothelial cells, leads to a typical phenotype of left ventricular noncompaction (LVNC). Mechanistically, the deletion of Ptbp1 reduces the migration of endothelial cells, disrupting cardiomyocyte proliferation and ultimately leading to the LVNC. Further study shows that Ptbp1 deficiency changes the alternative splicing of ß-arrestin-1 (Arrb1), which affects endothelial cell migration. In conclusion, as an alternative splicing factor, PTBP1 is essential during ventricular chamber development, and its deficiency can lead to congenital heart disease.


Assuntos
Células Endoteliais , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Células Endoteliais/metabolismo , Processamento Alternativo/genética , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo
10.
Sci China Life Sci ; 66(6): 1264-1279, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36808292

RESUMO

Histone modifications play crucial roles in the pathogenesis of myocardial ischaemia/reperfusion (I/R) injury. However, a genome-wide map of histone modifications and the underlying epigenetic signatures in myocardial I/R injury have not been established. Here, we integrated transcriptome and epigenome of histone modifications to characterize epigenetic signatures after I/R injury. Disease-specific histone mark alterations were mainly found in H3K27me3-, H3K27ac-, and H3K4me1-marked regions 24 and 48 h after I/R. Genes differentially modified by H3K27ac, H3K4me1 and H3K27me3 were involved in immune response, heart conduction or contraction, cytoskeleton, and angiogenesis. H3K27me3 and its methyltransferase polycomb repressor complex 2 (PRC2) were upregulated in myocardial tissues after I/R. Upon selective inhibition of EZH2 (the catalytic core of PRC2), the mice manifest improved cardiac function, enhanced angiogenesis, and reduced fibrosis. Further investigations confirmed that EZH2 inhibition regulated H3K27me3 modification of multiple pro-angiogenic genes and ultimately enhanced angiogenic properties in vivo and in vitro. This study delineates a landscape of histone modifications in myocardial I/R injury, and identifies H3K27me3 as a key epigenetic modifier in I/R process. The inhibition of H3K27me3 and its methyltransferase might be a potential strategy for myocardial I/R injury intervention.


Assuntos
Proteínas de Drosophila , Traumatismo por Reperfusão Miocárdica , Camundongos , Animais , Histonas/metabolismo , Complexo Repressor Polycomb 2/genética , Complexo Repressor Polycomb 2/metabolismo , Código das Histonas/genética , Traumatismo por Reperfusão Miocárdica/genética , Proteínas do Grupo Polycomb
11.
Acta Cardiol Sin ; 38(6): 778-783, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36440240

RESUMO

Background: Even though the proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, alirocumab and evolocumab, have been approved to reduce plasma low-density lipoprotein cholesterol (LDL-C) and the risk of atherosclerotic cardiovascular disease in high-risk patients, real-world data showing comparisons of the lipid-lowering effects between alirocumab and evolocumab are scarce because of the low prescription rates of PCSK9 inhibitors in clinical practice. Methods: Between Feb 2018 and Sep 2021, 22 patients who received alirocumab and 22 patients who received evolocumab at a tertiary medical center were enrolled. The patients' baseline characteristics, prescribed medications, plasma LDL-C levels, and percentages of reduction in LDL-C were compared between alirocumab users and evolocumab users. Results: The alirocumab users more frequently received ezetimibe treatment (72.7% vs. 40.9%, p = 0.03) and had higher baseline LDL-C (165.6 ± 63.2 mg/dL vs. 130.8 ± 56.3 mg/dL, p = 0.04) compared with the evolocumab users. At 6 months of follow-up, the plasma LDL-C levels in the alirocumab users were similar to those in the evolocumab users (79.3 ± 64.0 mg/dL vs. 63.5 ± 44.1 mg/dL, p = 0.48). Additionally, the percentages of LDL-C reduction following treatment were similar between the alirocumab users and evolocumab users (-47.0% ± 45.0% vs. -49.8 ± 24.9%, p = 0.66). Conclusions: The LDL-C lowering effects of alirocumab are similar to those of evolocumab in clinical practice.

13.
Nat Commun ; 13(1): 4433, 2022 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-35907876

RESUMO

Kinase-catalyzed phosphorylation plays a crucial role in pathological cardiac hypertrophy. Here, we show that CDC-like kinase 4 (CLK4) is a critical regulator of cardiomyocyte hypertrophy and heart failure. Knockdown of Clk4 leads to pathological cardiomyocyte hypertrophy, while overexpression of Clk4 confers resistance to phenylephrine-induced cardiomyocyte hypertrophy. Cardiac-specific Clk4-knockout mice manifest pathological myocardial hypertrophy with progressive left ventricular systolic dysfunction and heart dilation. Further investigation identifies nexilin (NEXN) as the direct substrate of CLK4, and overexpression of a phosphorylation-mimic mutant of NEXN is sufficient to reverse the hypertrophic growth of cardiomyocytes induced by Clk4 knockdown. Importantly, restoring phosphorylation of NEXN ameliorates myocardial hypertrophy in mice with cardiac-specific Clk4 deletion. We conclude that CLK4 regulates cardiac function through phosphorylation of NEXN, and its deficiency may lead to pathological cardiac hypertrophy. CLK4 is a potential intervention target for the prevention and treatment of heart failure.


Assuntos
Cardiomegalia , Insuficiência Cardíaca , Animais , Cardiomegalia/patologia , Modelos Animais de Doenças , Insuficiência Cardíaca/metabolismo , Camundongos , Camundongos Knockout , Proteínas dos Microfilamentos/metabolismo , Miócitos Cardíacos/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases , Proteínas Tirosina Quinases
14.
Cell Res ; 32(9): 843-854, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35840807

RESUMO

The sinoatrial node (SAN) is the origin of the electrical signals for rhythmic heartbeats in mammals. The spontaneous firing of SAN pacemaker cells (SANPCs) triggers cardiac contraction. 'Local Ca2+ release' (LCR), a unique cellular activity, acts as the 'engine' of the spontaneous firing of SANPCs. However, the mechanism of LCR initiation remains unclear. Here, we report that endogenous glutamate drives LCRs in SANPCs. Using a glutamate sensor, we unraveled a tight correlation between glutamate accumulation and LCR occurrence, indicating a potential relationship between glutamate and LCRs. Intracellular application of glutamate significantly enhanced the LCRs in both intact and permeabilized SANPCs. Mechanistically, we revealed that mitochondrial excitatory amino acid transporter 1 (EAAT1)-dependent mitochondrial glutamate import promoted ROS generation, which in turn led to the oxidation of Ca2+-handling proteins, ultimately resulting in enhanced LCRs. Importantly, EAAT1 depletion reduced both the spontaneous firing rates of isolated SANPCs and the heart rate in vitro and in vivo, suggesting the central role of EAAT1 as a glutamate transporter in the regulation of cardiac autonomic rhythm. In conclusion, our results indicate that glutamate serves as an LCR igniter in SANPCs, adding a potentially important element to the coupled-clock theory that explains the origin of spontaneous firing. These findings shed new light on the future prevention and treatment of cardiac pacemaker cell-related arrhythmias.


Assuntos
Ácido Glutâmico , Nó Sinoatrial , Animais , Cálcio/metabolismo , Ácido Glutâmico/metabolismo , Mamíferos , Miócitos Cardíacos/metabolismo , Nó Sinoatrial/metabolismo
15.
J Am Psychiatr Nurses Assoc ; : 10783903221096360, 2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35620801

RESUMO

BACKGROUND: Negative attitudes toward mental disorders are not only an interpersonal issue but also a concern of mental health care. Given that nursing students are future health care providers, it is pivotal to improve their attitudes toward individuals with mental disorders prior to their transition into clinical practice. However, research on nursing students' attitudes in relation to schizophrenia in Taiwan remains unexplored. AIM: The aim of this article is to examine the correlates of attitudes toward individuals with schizophrenia among Taiwanese undergraduate nursing students. METHOD: A descriptive, correlational, and cross-sectional study was adopted. Self-reported questionnaires were conducted with a convenience sample of 306 Taiwanese undergraduate nursing students. Descriptive statistics, independent t tests, one-way analysis of variance, Pearson's correlations, and a stepwise regression analysis were performed. RESULTS: Nursing students expressed negative attitudes toward individuals with schizophrenia. Nursing students, who were female, had contact with individuals with mental disorders, and expressed greater empathy and personality traits held more favorable attitudes toward individuals with schizophrenia. The study found that empathy, personality traits, and academic year were the most crucial attributes contributing to attitudes of nursing students toward individuals with schizophrenia. CONCLUSION: Findings suggest that nursing education programs with empathy- and personality-tailored modules in mental health are pivotal to provide humanistic approaches with supportive attitudes regarding schizophrenia.

16.
J Cell Mol Med ; 26(10): 2981-2994, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35429093

RESUMO

The neonatal heart can efficiently regenerate within a short period after birth, whereas the adult mammalian heart has extremely limited capacity to regenerate. The molecular mechanisms underlying neonatal heart regeneration remain elusive. Here, we revealed that as a coreceptor of Wnt signalling, low-density lipoprotein receptor-related protein 5 (LRP5) is required for neonatal heart regeneration by regulating cardiomyocyte proliferation. The expression of LRP5 in the mouse heart gradually decreased after birth, consistent with the time window during which cardiomyocytes withdrew from the cell cycle. LRP5 downregulation reduced the proliferation of neonatal cardiomyocytes, while LRP5 overexpression promoted cardiomyocyte proliferation. The cardiac-specific deletion of Lrp5 disrupted myocardial regeneration after injury, exhibiting extensive fibrotic scars and cardiac dysfunction. Mechanistically, the decreased heart regeneration ability induced by LRP5 deficiency was mainly due to reduced cardiomyocyte proliferation. Further study identified AKT/P21 signalling as the key pathway accounting for the regulation of cardiomyocyte proliferation mediated by LRP5. LRP5 downregulation accelerated the degradation of AKT, leading to increased expression of the cyclin-dependent kinase inhibitor P21. Our study revealed that LRP5 is necessary for cardiomyocyte proliferation and neonatal heart regeneration, providing a potential strategy to repair myocardial injury.


Assuntos
Coração , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Miócitos Cardíacos , Regeneração , Animais , Proliferação de Células , Coração/fisiologia , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Camundongos , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Via de Sinalização Wnt
17.
J Am Chem Soc ; 144(3): 1323-1331, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-35037455

RESUMO

As an aberrant base in DNA, uracil is generated by either deoxyuridine (dU) misincorporation or cytosine deamination, and involved in multiple physiological and pathological processes. Genome-wide profiles of uracil are important for study of these processes. Current methods for whole-genome mapping of uracil all rely on uracil-DNA N-glycosylase (UNG) and are limited in resolution, specificity, and/or sensitivity. Here, we developed a UdgX cross-linking and polymerase stalling sequencing ("Ucaps-seq") method to detect dU at single-nucleotide resolution. First, the specificity of Ucaps-seq was confirmed on synthetic DNA. Then the effectiveness of the approach was verified on two genomes from different sources. Ucaps-seq not only identified the enrichment of dU at dT sites in pemetrexed-treated cancer cells with globally elevated uracil but also detected dU at dC sites within the "WRC" motif in activated B cells which have increased dU in specific regions. Finally, Ucaps-seq was utilized to detect dU introduced by the cytosine base editor (nCas9-APOBEC) and identified a novel off-target site in cellular context. In conclusion, Ucaps-seq is a powerful tool with many potential applications, especially in evaluation of base editing fidelity.


Assuntos
Nucleotídeos
18.
J Pers Med ; 13(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36675730

RESUMO

Hypertriglyceridemia (HTG) remains a risk-enhancing factor of atherosclerotic cardiovascular disease. We aimed to report real-world data on the management of patients with type V hyperlipoproteinemia (HLP5), an uncommon phenotype of dyslipidemia characterized by fasting chylomicronemia and severe HTG. Between July 2018 and May 2021, 90 patients with HTG, including 83 patients with type IV hyperlipoproteinemia (HLP4) and 7 patients with HLP5, were identified by plasma apolipoprotein B (apoB) and lipoprotein electrophoresis. Patients with HLP5 were younger, had higher total cholesterol (TC) (264.9 ± 26.7 mg/dL vs. 183.9 ± 26.1 mg/dL; p < 0.01) and higher triglyceride (TG) (1296.7 ± 380.5 mg/dL vs. 247.6 ± 96.1 mg/dL; p < 0.01), and had lower high-density lipoprotein cholesterol (HDL-C) (30.6 ± 4.8 mg/dL vs. 40.5 ± 8.7 mg/dL; p < 0.01) and lower low-density lipoprotein cholesterol (LDL-C) (62.9 ± 16.4 vs. 103.0 ± 21.1 mg/dL; p < 0.01) compared with patients with HLP4. Despite an aggressive use of statin and fenofibrate with greater reductions in TG (-65.9 ± 13.7% vs. -27.9 ± 30.5%; p < 0.01) following 6 months of treatment, patients with HLP5 had persistent HTG (440.1 ± 239.0 mg/dL vs. 173.9 ± 94.8 mg/dL; p < 0.01) and an increase in LDL-C (28.3 ± 57.2% vs. -19.5 ± 32.0%; p < 0.01) compared with patients with HLP4. Our findings highlight that the lack of novel TG-lowering medications and management guidelines remains an unmet medical need in patients with HLP5. Closely monitoring lipid profiles, full assessment of individual's risk of cardiovascular disease, and emphasis on medication adherence are of clinical importance.

19.
Environ Technol ; 43(21): 3341-3354, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33886443

RESUMO

Antibiotic pollution of water resources is a global problem, and the development of new treatments for destroying antibiotics in water is a priority research. We successfully manufactured recyclable magnetic Fe3O4/g-C3N4 through the electrostatic self-assembly method. Selecting tetracycline (TC) as the target pollutant, using Fe3O4/g-C3N4 and H2O2 developed a heterogeneous optical Fenton system to remove TC under visible light. Fe3O4/g-C3N4 was systematically characterized by SEM, TEM, XRD, FTIR, XPS, DRS, and electrochemical methods. The removal efficiency of 7% Fe3O4/g-C3N4 at pH = 3, H2O2 = 5 mM, and catalyst dosage of 1.0 g/L can reach 99.8%. After magnetic separation, the Fe3O4/g-C3N4 photocatalyst can be recycled five times with minimal efficiency loss. The excellent degradation performance of the prepared catalyst may be attributed to the proper coupling interface between Fe3O4 and g-C3N4 which promotes the separation and transfer of photogenerated electrons. Photogenerated electrons can also accelerate the conversion of Fe3+ to Fe2+, thereby producing more ˙OH. The new Fe3O4/g-C3N4 can be used as a raw material for advanced oxidation of water contaminated by refractory antibiotics.


Assuntos
Peróxido de Hidrogênio , Tetraciclina , Antibacterianos , Catálise , Peróxido de Hidrogênio/química , Luz , Água
20.
J Formos Med Assoc ; 121(1 Pt 2): 425-433, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34144861

RESUMO

BACKGROUND: This study was to perform an economic evaluation to understand clinical outcomes and health resource use between hip fracture patients receiving hospital-based postfracture fracture liaison service (FLS) care and those receiving usual care (UC) in Taiwan. METHODS: This cohort study included hospital-based data of 174 hip fracture patients who received FLS care (FLS group) from National Taiwan University Hospital, and 1697 propensity score-matched patients who received UC (UC group) of National Health Insurance claim-based data. Two groups had similar baseline characteristics but differed in hip fracture care after propensity score matching. Clinical outcomes included refracture-free survival (RFS), hip-refracture-free survival (HRFS), and overall survival (OS). Health resource use included inpatient, outpatient, and pharmacy costs within 2 years follow-up after the index of hip fracture. The economic evaluation of the FLS model was analyzed using the net monetary benefit regression framework based on the National Health Insurance perspective. RESULTS: The FLS group had longer RFS than the UC group, with an adjusted difference of 44.3 days (95% confidence interval: 7.2-81.4 days). Two groups did not differ in inpatient and outpatient costs during follow-up, but the FLS group had a higher expenditure than the UC group on osteoporosis-related medication. The probability of FLS being cost-effective was >80% and of increasing RFS, HRFS, and OS was 95%, 81%, and 80%, respectively, when the willingness-to-pay threshold was >USD 65/gross domestic product per day. CONCLUSION: FLS care was cost-effective in reducing refracture occurrence days for patients initially diagnosed with hip fractures.


Assuntos
Fraturas do Quadril , Estudos de Coortes , Análise Custo-Benefício , Fraturas do Quadril/terapia , Humanos , Taiwan
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