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1.
Circulation ; 148(23): 1887-1906, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-37905452

RESUMO

BACKGROUND: The importance of mitochondria in normal heart function are well recognized and recent studies have implicated changes in mitochondrial metabolism with some forms of heart disease. Previous studies demonstrated that knockdown of the mitochondrial ribosomal protein S5 (MRPS5) by small interfering RNA (siRNA) inhibits mitochondrial translation and thereby causes a mitonuclear protein imbalance. Therefore, we decided to examine the effects of MRPS5 loss and the role of these processes on cardiomyocyte proliferation. METHODS: We deleted a single allele of MRPS5 in mice and used left anterior descending coronary artery ligation surgery to induce myocardial damage in these animals. We examined cardiomyocyte proliferation and cardiac regeneration both in vivo and in vitro. Doxycycline treatment was used to inhibit protein translation. Heart function in mice was assessed by echocardiography. Quantitative real-time polymerase chain reaction and RNA sequencing were used to assess changes in transcription and chromatin immunoprecipitation (ChIP) and BioChIP were used to assess chromatin effects. Protein levels were assessed by Western blotting and cell proliferation or death by histology and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assays. Adeno-associated virus was used to overexpress genes. The luciferase reporter assay was used to assess promoter activity. Mitochondrial oxygen consumption rate, ATP levels, and reactive oxygen species were also analyzed. RESULTS: We determined that deletion of a single allele of MRPS5 in mice results in elevated cardiomyocyte proliferation and cardiac regeneration; this observation correlates with improved cardiac function after induction of myocardial infarction. We identified ATF4 (activating transcription factor 4) as a key regulator of the mitochondrial stress response in cardiomyocytes from Mrps5+/- mice; furthermore, ATF4 regulates Knl1 (kinetochore scaffold 1) leading to an increase in cytokinesis during cardiomyocyte proliferation. The increased cardiomyocyte proliferation observed in Mrps5+/- mice was attenuated when one allele of Atf4 was deleted genetically (Mrps5+/-/Atf4+/-), resulting in the loss in the capacity for cardiac regeneration. Either MRPS5 inhibition (or as we also demonstrate, doxycycline treatment) activate a conserved regulatory mechanism that increases the proliferation of human induced pluripotent stem cell-derived cardiomyocytes. CONCLUSIONS: These data highlight a critical role for MRPS5/ATF4 in cardiomyocytes and an exciting new avenue of study for therapies to treat myocardial injury.


Assuntos
Células-Tronco Pluripotentes Induzidas , Miócitos Cardíacos , Humanos , Camundongos , Animais , Miócitos Cardíacos/metabolismo , Doxiciclina , Células Cultivadas , Células-Tronco Pluripotentes Induzidas/metabolismo , RNA Interferente Pequeno/metabolismo , Biossíntese de Proteínas , Proliferação de Células , Regeneração , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo
2.
Physiol Rev ; 97(1): 227-252, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27881552

RESUMO

Unique to striated muscle cells, transverse tubules (t-tubules) are membrane organelles that consist of sarcolemma penetrating into the myocyte interior, forming a highly branched and interconnected network. Mature t-tubule networks are found in mammalian ventricular cardiomyocytes, with the transverse components of t-tubules occurring near sarcomeric z-discs. Cardiac t-tubules contain membrane microdomains enriched with ion channels and signaling molecules. The microdomains serve as key signaling hubs in regulation of cardiomyocyte function. Dyad microdomains formed at the junctional contact between t-tubule membrane and neighboring sarcoplasmic reticulum are critical in calcium signaling and excitation-contraction coupling necessary for beat-to-beat heart contraction. In this review, we provide an overview of the current knowledge in gross morphology and structure, membrane and protein composition, and function of the cardiac t-tubule network. We also review in detail current knowledge on the formation of functional membrane subdomains within t-tubules, with a particular focus on the cardiac dyad microdomain. Lastly, we discuss the dynamic nature of t-tubules including membrane turnover, trafficking of transmembrane proteins, and the life cycles of membrane subdomains such as the cardiac BIN1-microdomain, as well as t-tubule remodeling and alteration in diseased hearts. Understanding cardiac t-tubule biology in normal and failing hearts is providing novel diagnostic and therapeutic opportunities to better treat patients with failing hearts.


Assuntos
Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/ultraestrutura , Sarcolema/metabolismo , Sarcolema/ultraestrutura , Animais , Humanos
3.
FASEB J ; 37(2): e22742, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36583723

RESUMO

The Chinese forest musk deer (FMD; Moschus berezovskii) is an endangered artiodactyl mammal. Musk secreted by the musk gland of male has extremely high economic and medicinal value. However, the molecular and cellular characteristics of the musk gland have not been studied. Here, we investigated the diversity and transcriptional composition of musk gland cell types and the effect of cell type-specific chromatin accessibility on gene expression using single-nucleus RNA sequencing (snRNA-seq) and single-nucleus ATAC sequencing (snATAC-seq) association analysis. Based on uniform manifold approximation and projection (UMAP) analysis, we identified 13 cell types from the musk gland, which included two different acinar cells (cluster 0 and cluster 10). Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis indicated that many pathways related to musk secretion were enriched in acinar cells. Our analysis also revealed acinar cell core transcription factors and core target genes, and further constructed acinar cell-specific regulatory networks. In cluster 0, 11 core target genes (Nedd4l, Adcy9, Akr1c1, Vapb, Me1, Acsl1, Acss3, Srd5a1, Scnn1a, Acadm, and Nceh1) possibly related to musk secretion were regulated by 24 core transcription factors (SP3, NFIC, NR6A1, EHF, RUNX1, TFAP2A, RREB1, GRHL2, NFIB, ELF1, MAX, KLF5, REL, HES1, POU2F3, TFDP1, NR2C1, ATF7, MEIS1, NR4A2, NFIA, PBX1, ZNF652, and NFKB1). In cluster 10, four core target genes (Akr1c1, Pcca, Atp1b1, and Sgk1) possibly related to musk secretion were regulated by 10 core transcription factors (BARX2, EHF, PBX1, RUNX1, NFIB, FOXP1, KLF3, KLF6, ETV6, and NR3C2). Moreover, the credibility of snRNA-seq and snATAC-seq data was verified by fluorescence in situ hybridization and immunohistochemistry. Finally, cell communication analysis demonstrated that the two types of acinar cells mainly have communications in musk secretion-related processes. In conclusion, we provided important insights and invaluable resources for the molecular and cellular characteristics of the musk gland, which will lay a foundation for the study of musk secretion mechanism in the future.


Assuntos
Cervos , Masculino , Animais , Cervos/genética , Cervos/metabolismo , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , RNA/metabolismo , Hibridização in Situ Fluorescente , Florestas , RNA Nuclear Pequeno/metabolismo
4.
Nucleic Acids Res ; 50(12): e69, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35325178

RESUMO

The nucleolus is a subnuclear membraneless compartment intimately involved in ribosomal RNA synthesis, ribosome biogenesis and stress response. Multiple optogenetic devices have been developed to manipulate nuclear protein import and export, but molecular tools tailored for remote control over selective targeting or partitioning of cargo proteins into subnuclear compartments capable of phase separation are still limited. Here, we report a set of single-component photoinducible nucleolus-targeting tools, designated pNUTs, to enable rapid and reversible nucleoplasm-to-nucleolus shuttling, with the half-lives ranging from milliseconds to minutes. pNUTs allow both global protein infiltration into nucleoli and local delivery of cargoes into the outermost layer of the nucleolus, the granular component. When coupled with the amyotrophic lateral sclerosis (ALS)-associated C9ORF72 proline/arginine-rich dipeptide repeats, pNUTs allow us to photomanipulate poly-proline-arginine nucleolar localization, perturb nucleolar protein nucleophosmin 1 and suppress nascent protein synthesis. pNUTs thus expand the optogenetic toolbox by permitting light-controllable interrogation of nucleolar functions and precise induction of ALS-associated toxicity in cellular models.


Assuntos
Esclerose Lateral Amiotrófica , Nucléolo Celular , Optogenética/métodos , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/metabolismo , Proteína C9orf72/química , Nucléolo Celular/metabolismo , Sistemas de Liberação de Medicamentos , Humanos , Proteínas Nucleares/metabolismo , Inibidores da Síntese de Proteínas/administração & dosagem
5.
Am J Physiol Heart Circ Physiol ; 324(6): H751-H761, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36961487

RESUMO

Preclinical large animal models of chronic heart failure (HF) are crucial to both understanding pathological remodeling and translating fundamental discoveries into novel therapeutics for HF. Canine models of ischemic cardiomyopathy are historically limited by either high early mortality or failure to develop chronic heart failure. Twenty-nine healthy adult dogs (30 ± 4 kg, 15/29 male) underwent thoracotomy followed by one of three types of left anterior descending (LAD) coronary artery ligation procedures: group 1 (n = 4) (simple LAD: proximal and distal LAD ligation); group 2 (n = 14) (simple LAD plus lateral wall including ligation of the distal first diagonal and proximal first obtuse marginal); and group 3 (n = 11) (total LAD devascularization or TLD: simple LAD plus ligation of proximal LAD branches to both the right and left ventricles). Dogs were followed until chronic severe HF developed defined as left ventricular ejection fraction (LVEF) < 40% and NH2-terminal-prohormone B-type natriuretic peptide (NT-proBNP) > 900 pmol/L. Overall early survival (48-h postligation) in 29 dogs was 83% and the survival rate at postligation 5 wk was 69%. Groups 1 and 2 had 100% and 71% early survival, respectively, yet only a 50% success rate of developing chronic HF. Group 3 had excellent survival at postligation 48 h (91%) and a 100% success in the development of chronic ischemic HF. The TLD approach, which limits full LAD and collateral flow to its perfusion bed, provides excellent early survival and reliable development of chronic ischemic HF in canine hearts.NEW & NOTEWORTHY The novel total left anterior descending devascularization (TLD) approach in a canine ischemic heart failure model limits collateral flow in the ischemic zone and provides excellent early survival and repeatable development of chronic ischemic heart failure in the canine heart. This work provides a consistent large animal model for investigating heart failure mechanisms and testing novel therapeutics.


Assuntos
Insuficiência Cardíaca , Função Ventricular Esquerda , Cães , Masculino , Animais , Volume Sistólico , Insuficiência Cardíaca/etiologia , Coração , Doença Crônica , Modelos Animais de Doenças
6.
Stem Cells ; 40(3): 260-272, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35296897

RESUMO

Ten-eleven Translocation (TET) dioxygenases mediated DNA methylation oxidation plays an important role in regulating the embryonic stem cells (ESCs) differentiation. Herein, we utilized a CRISPR/Cas9 based genome editing method to generate single, double, and triple Tet-deficient mouse ESCs (mESCs) and differentiated these cells toward cardiac progenitors. By using emerald green fluorescent protein (GFP; emGFP) expression under the control of Nkx2.5 promoter as marker for cardiac progenitor cells, we discovered that Tet1 and Tet2 depletion significantly impaired mESC-to-cardiac progenitor differentiation. Single-cell RNA-seq analysis further revealed that Tet deletion resulted in the accumulation of mesoderm progenitors to hamper cardiac differentiation. Re-expression of the Tet1 catalytic domain (Tet1CD) rescued the differentiation defect in Tet-triple knockout mESCs. Dead Cas9 (dCas9)-Tet1CD mediated loci-specific epigenome editing at the Hand1 loci validated the direct involvement of Tet-mediated epigenetic modifications in transcriptional regulation during cardiac differentiation. Our study establishes that Tet-mediated epigenetic remodeling is essential for maintaining proper transcriptional outputs to safeguard mESC-to-cardiac progenitor differentiation.


Assuntos
Células-Tronco Embrionárias Murinas , Proteínas Proto-Oncogênicas , Animais , Diferenciação Celular/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células-Tronco Embrionárias/metabolismo , Camundongos , Células-Tronco Embrionárias Murinas/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo
7.
Mikrochim Acta ; 190(9): 357, 2023 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-37597027

RESUMO

Novel chiral capillary electrochromatography (CEC) microsystems were constructed based on Aspergillus sp. CM96. As a newly discovered intrinsic characteristic of the cell, cell chirality occupies an essential position in life evolution. Aspergillus sp. CM96 spore (CM96s) was chosen as a proof of concept to develop chiral capillary columns. Interestingly, various types of amino acid (AA) enantiomers were baseline separated under the optimized conditions. Furthermore, the time-dependent chiral interactions between AAs and CM96s were explored in a wider space. Pectinases generated from Aspergillus sp. CM96 fermentation were immobilized onto graphene oxide-functionalized capillary silica monoliths for separating AA enantiomers. Molecular docking simulations were performed to explore chiral separation mechanisms of pectinase for AA enantiomers. These results indicated that Aspergillus sp. CM96-based CEC microsystems have a significant advantage for chiral separation.


Assuntos
Eletrocromatografia Capilar , Simulação de Acoplamento Molecular , Aspergillus , Aminoácidos , Dióxido de Silício
8.
Cell Mol Neurobiol ; 42(6): 1659-1669, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33638766

RESUMO

The tetrapeptide repeat domain 3 (TTC3) gene falls within Down's syndrome (DS) critical region. Cognitive impairment is a common phenotype of DS and Alzheimer's disease (AD), and overexpression of TTC3 can accelerate cognitive decline, but the specific mechanism is unknown. The TTC3-mediated protein quality control (PQC) mechanism, similar to the PQC system, is divided into three parts: it acts as a cochaperone to assist proteins in folding correctly; it acts as an E3 ubiquitin ligase (E3s) involved in protein degradation processes through the ubiquitin-proteasome system (UPS); and it may also eventually cause autophagy by affecting mitochondrial function. Thus, this article reviews the research progress on the structure, function, and metabolism of TTC3, including the recent research progress on TTC3 in DS and AD; the role of TTC3 in cognitive impairment through PQC in combination with the abovementioned attributes of TTC3; and the potential targets of TTC3 in the treatment of such diseases.


Assuntos
Disfunção Cognitiva , Ubiquitina-Proteína Ligases , Doença de Alzheimer/genética , Disfunção Cognitiva/genética , Síndrome de Down/genética , Humanos , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
9.
Bull Environ Contam Toxicol ; 110(1): 15, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36520278

RESUMO

This study aimed to investigate the effect of 10-40 mg L-1 polystyrene microplastics (PS-MPs), 0.05 mg L-1 cadmium (Cd) and their combination on the growth and related physiological and toxicological responses in Oryza sativa L. seedling roots. Results showed that the fresh weight, dry weight and root lengths of treatments by PS-MPs, Cd single and combinative were all lower than the control, and opposite phenomenon appeared in production of superoxide radical (O2-.), malondialdehyde (MDA) and carbonylated protein. Superoxide dismutase (SOD) and guaiacol peroxidase (POD) activities induced by 10-40 mg L-1 PS-MPs and combination with Cd were almost higher than those by Cd alone, expression of heat shock protein (HSP)70 and carbonylated protein slightly decreased. In compound exposure, 10-20 mg L-1 PS-MPs alleviated Cd damage and promoted root growth by increasing SOD and POD activities, but 40 mg L-1 PS-MPs accelerated the accumulation of Cd, MDA, and O2-., which was responsible for decreasing root biomass and the aggravating necrosis of root tip cells.


Assuntos
Cádmio , Oryza , Cádmio/toxicidade , Cádmio/metabolismo , Plântula , Microplásticos/metabolismo , Plásticos , Raízes de Plantas/metabolismo , Estresse Oxidativo , Antioxidantes/metabolismo , Superóxido Dismutase/metabolismo
10.
Basic Res Cardiol ; 116(1): 48, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34379189

RESUMO

Metabolic modulation is a promising therapeutic approach to prevent adverse remodeling of the ischemic heart. Because little is known about the involvement of long non-coding RNAs (lncRNAs) in regulating cardiac metabolism, we used unbiased transcriptome profiling in a mouse model of myocardial infarction (MI). We identified a novel cardiomyocyte-enriched lncRNA, called LncHrt, which regulates metabolism and the pathophysiological processes that lead to heart failure. AAV-based LncHrt overexpression protects the heart from MI as demonstrated by improved contractile function, preserved metabolic homeostasis, and attenuated maladaptive remodeling responses. RNA-pull down followed by mass spectrometry and RNA immunoprecipitation (RIP) identified SIRT2 as a LncHrt-interacting protein involved in cardiac metabolic regulation. Mechanistically, we established that LncHrt interacts with SIRT2 to preserve SIRT2 deacetylase activity by interfering with the CDK5 and SIRT2 interaction. This increases downstream LKB1-AMPK kinase signaling, which ameliorates functional and metabolic deficits. Importantly, we found the expression of the human homolog of mouse LncHrt was decreased in patients with dilated cardiomyopathy. Together, these studies identify LncHrt as a cardiac metabolic regulator that plays an essential role in preserving heart function by regulating downstream metabolic signaling pathways. Consequently, LncHrt is a potentially novel RNA-based therapeutic target for ischemic heart disease.


Assuntos
RNA Longo não Codificante , Quinases Proteína-Quinases Ativadas por AMP , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Homeostase , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , RNA Longo não Codificante/genética , Transdução de Sinais
11.
Electrophoresis ; 42(11): 1217-1220, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33675051

RESUMO

A novel peptide containing antimicrobial sequence and gelatinase cleavage sites was designed for Staphylococcus aureus detection. Since Staphylococcus aureus could secrete gelatinase, the fluorescein labeled peptide GKRWWKWWRRPLGVRGC could be recognized and cleaved. The obtained products were able to be analyzed by capillary electrophoresis with fluorescence detection. To explore the effect of Staphylococcus aureus concentration on enzyme digestion ability of peptide, Staphylococcus aureus with different concentrations were incubated with the peptide. Results indicated that capillary electrophoretic method was efficient for determining Staphylococcus aureus content. Compared with traditional approaches for Staphylococcus aureus detection, capillary electrophoresis possessed higher efficiency, enhanced sensitivity, and low sample consumption. Moreover, the proposed peptide also presented desirable antimicrobial activity. It suggested that the novel antimicrobial peptide used in this research opens a new path of detecting Staphylococcus aureus by capillary electrophoretic method.


Assuntos
Peptídeos Antimicrobianos , Staphylococcus aureus , Sequência de Aminoácidos , Eletroforese Capilar , Fluoresceína , Gelatinases , Staphylococcus aureus/isolamento & purificação
12.
Analyst ; 146(1): 48-63, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33211035

RESUMO

DNA possesses various chemical and physical properties which make it important in biological analysis. The opportunity for DNA to 'meet' capillary-based microsystems is rapidly increasing owing to the expanding development of miniaturization. Novel capillary-based methods can provide favourable platforms for DNA-ligand interaction assay, DNA translocation study, DNA separation, DNA aptamer selection, DNA amplification assay, and DNA digestion. Meanwhile, DNA exhibits great potential in the fabrication of new capillary-based biosensors and enzymatic bioreactors. Moreover, DNA has received significant research interest in improving capillary electrophoresis (CE) performance. We focus on highlighting the advantages of combining DNA and capillary-based microsystems. The general trend presented in this review suggests that the 'meeting' has offered a stepping stone for the application of DNA and capillary-based microsystems in the field of analytical chemistry.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , DNA/genética , Eletroforese Capilar , Miniaturização
13.
Int J Mol Sci ; 22(5)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33669042

RESUMO

Since its first identification as a cardiac transverse tubule (t-tubule) protein, followed by the cloning of the cardiac isoform responsible for t-tubule membrane microdomain formation, cardiac bridging integrator 1 (cBIN1) and its organized microdomains have emerged as a key mechanism in maintaining normal beat-to-beat heart contraction and relaxation. The abnormal remodeling of cBIN1-microdomains occurs in stressed and diseased cardiomyocytes, contributing to the pathophysiology of heart failure. Due to the homeostatic turnover of t-tubule cBIN1-microdomains via microvesicle release into the peripheral circulation, plasma cBIN1 can be assayed as a liquid biopsy of cardiomyocyte health. A new blood test cBIN1 score (CS) has been developed as a dimensionless inverse index derived from plasma cBIN1 concentration with a diagnostic and prognostic power for clinical outcomes in stable ambulatory patients with heart failure with reduced or preserved ejection fraction (HFrEF or HFpEF). Recent evidence further indicates that exogenous cBIN1 introduced by adeno-associated virus 9-based gene therapy can rescue cardiac contraction and relaxation in failing hearts. The therapeutic potential of cBIN1 gene therapy is enormous given its ability to rescue cardiac inotropy and provide lusitropic protection in the meantime. These unprecedented capabilities of cBIN1 gene therapy are shifting the current paradigm of therapy development for heart failure, particularly HFpEF.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/sangue , Terapia Genética/métodos , Insuficiência Cardíaca/sangue , Miócitos Cardíacos/metabolismo , Proteínas Nucleares/sangue , Retículo Sarcoplasmático/metabolismo , Proteínas Supressoras de Tumor/sangue , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Biomarcadores/sangue , Sinalização do Cálcio/fisiologia , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Humanos , Proteínas de Membrana/metabolismo , Contração Miocárdica , Miócitos Cardíacos/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Domínios Proteicos , Sarcolema/metabolismo , Retículo Sarcoplasmático/patologia , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
14.
Zhongguo Zhong Yao Za Zhi ; 46(17): 4410-4416, 2021 Sep.
Artigo em Zh | MEDLINE | ID: mdl-34581044

RESUMO

This study was mainly based on the compatibility of Puerariae Lobatae Radix and Chuanxiong Rhizoma to prepare submicron emulsion and evaluated its physical and pharmaceutical properties. Firstly, pseudo-ternary phase diagrams were drawn by dripping method which took Chuanxiong oil as the oil phase and the area of microemulsion region as the index. On this basis, suitable emulsifier and co-emulsifier were screened for the preparation of Chuanxiong oil submicron emulsion. Then, the formula realizing the largest oil loading was selected. Finally, puerarin substituted part of emulsifier and co-emulsifier to lower their content, so as to form puerarin-Chuanxiong oil submicron emulsion featuring the combination of medicine and adjuvant. Its particle size, zeta potential, centrifugal stability and storage stability were determined, and the in vitro drug release behavior was investigated by dialysis bag method, based on which the quality of the as-prepared submicron emulsion was evaluated comprehensively. The proposed method was proved feasible for the preparation of Chuanxiong oil submicron emulsion, which adopted polyoxyethylene castor oil(EL-40) as the emulsifier and was free from co-emulsifier. The formula of the maximum oil loading was found as Chuanxiong oil∶EL-40∶water 3∶7∶90. Further, puera-rin successfully replaced up to 10% of the emulsifier in submicron emulsion. Eventually, the optimal drug-loading formula was determined as puerarin∶Chuanxiong oil∶EL-40∶water 7∶30∶63∶900. The quality evaluation results of the as-prepared submicron emulsion demonstrated that the average emulsion droplet size was 333.9 nm, the PDI 0.26, and the zeta potential-10.12 mV. The submicron emulsion had a good centrifugal stability and did not present any instable phenomena such as delamination and precipitation during its standing still for 50 days. The evaluation of in vitro drug release behavior indicated that the submicron emulsion was capable of releasing the drug completely. The puerarin-chuanxiong oil submicron emulsion prepared in this study possessed a stable quality and to some extent increased the solubility of puerarin along with a sustained-release effect. This study provided ideas for the clinical application of puerarin.


Assuntos
Isoflavonas , Emulsões , Tamanho da Partícula , Solubilidade
15.
Am J Physiol Cell Physiol ; 318(1): C163-C173, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31747312

RESUMO

Fluorescence recovery after photobleaching (FRAP) has been useful in delineating cardiac myofilament biology, and innovations in fluorophore chemistry have expanded the array of microscopic assays used. However, one assumption in FRAP is the irreversible photobleaching of fluorescent proteins after laser excitation. Here we demonstrate reversible photobleaching regarding the photoconvertible fluorescent protein mEos3.2. We used CRISPR/Cas9 genome editing in human induced pluripotent stem cells (hiPSCs) to knock-in mEos3.2 into the COOH terminus of titin to visualize sarcomeric titin incorporation and turnover. Upon cardiac induction, the titin-mEos3.2 fusion protein is expressed and integrated in the sarcomeres of hiPSC-derived cardiomyocytes (CMs). STORM imaging shows M-band clustered regions of bound titin-mEos3.2 with few soluble titin-mEos3.2 molecules. FRAP revealed a baseline titin-mEos3.2 fluorescence recovery of 68% and half-life of ~1.2 h, suggesting a rapid exchange of sarcomeric titin with soluble titin. However, paraformaldehyde-fixed and permeabilized titin-mEos3.2 hiPSC-CMs surprisingly revealed a 55% fluorescence recovery. Whole cell FRAP analysis in paraformaldehyde-fixed, cycloheximide-treated, and untreated titin-mEos3.2 hiPSC-CMs displayed no significant differences in fluorescence recovery. FRAP in fixed HEK 293T expressing cytosolic mEos3.2 demonstrates a 58% fluorescence recovery. These data suggest that titin-mEos3.2 is subject to reversible photobleaching following FRAP. Using a mouse titin-eGFP model, we demonstrate that no reversible photobleaching occurs. Our results reveal that reversible photobleaching accounts for the majority of titin recovery in the titin-mEos3.2 hiPSC-CM model and should warrant as a caution in the extrapolation of reliable FRAP data from specific fluorescent proteins in long-term cell imaging.


Assuntos
Diferenciação Celular , Conectina/metabolismo , Recuperação de Fluorescência Após Fotodegradação , Células-Tronco Pluripotentes Induzidas/metabolismo , Microscopia de Fluorescência , Microscopia de Vídeo , Miócitos Cardíacos/metabolismo , Sarcômeros/metabolismo , Adulto , Linhagem Celular , Conectina/genética , Humanos , Cinética , Proteínas Luminescentes/metabolismo , Masculino , Proteínas Recombinantes de Fusão/metabolismo , Reprodutibilidade dos Testes , Sarcômeros/genética
16.
PLoS Biol ; 15(8): e2002354, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28806752

RESUMO

Microparticles (MPs) are cell-cell communication vesicles derived from the cell surface plasma membrane, although they are not known to originate from cardiac ventricular muscle. In ventricular cardiomyocytes, the membrane deformation protein cardiac bridging integrator 1 (cBIN1 or BIN1+13+17) creates transverse-tubule (t-tubule) membrane microfolds, which facilitate ion channel trafficking and modulate local ionic concentrations. The microfold-generated microdomains continuously reorganize, adapting in response to stress to modulate the calcium signaling apparatus. We explored the possibility that cBIN1-microfolds are externally released from cardiomyocytes. Using electron microscopy imaging with immunogold labeling, we found in mouse plasma that cBIN1 exists in membrane vesicles about 200 nm in size, which is consistent with the size of MPs. In mice with cardiac-specific heterozygous Bin1 deletion, flow cytometry identified 47% less cBIN1-MPs in plasma, supporting cardiac origin. Cardiac release was also evidenced by the detection of cBIN1-MPs in medium bathing a pure population of isolated adult mouse cardiomyocytes. In human plasma, osmotic shock increased cBIN1 detection by enzyme-linked immunosorbent assay (ELISA), and cBIN1 level decreased in humans with heart failure, a condition with reduced cardiac muscle cBIN1, both of which support cBIN1 release in MPs from human hearts. Exploring putative mechanisms of MP release, we found that the membrane fission complex endosomal sorting complexes required for transport (ESCRT)-III subunit charged multivesicular body protein 4B (CHMP4B) colocalizes and coimmunoprecipitates with cBIN1, an interaction enhanced by actin stabilization. In HeLa cells with cBIN1 overexpression, knockdown of CHMP4B reduced the release of cBIN1-MPs. Using truncation mutants, we identified that the N-terminal BAR (N-BAR) domain in cBIN1 is required for CHMP4B binding and MP release. This study links the BAR protein superfamily to the ESCRT pathway for MP biogenesis in mammalian cardiac ventricular cells, identifying elements of a pathway by which cytoplasmic cBIN1 is released into blood.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Micropartículas Derivadas de Células/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/sangue , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Micropartículas Derivadas de Células/química , Micropartículas Derivadas de Células/ultraestrutura , Células Cultivadas , Complexos Endossomais de Distribuição Requeridos para Transporte/antagonistas & inibidores , Complexos Endossomais de Distribuição Requeridos para Transporte/sangue , Complexos Endossomais de Distribuição Requeridos para Transporte/química , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/ultraestrutura , Ensaio de Imunoadsorção Enzimática , Éxons , Células HeLa , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/patologia , Heterozigoto , Humanos , Camundongos Transgênicos , Microscopia Eletrônica de Transmissão , Miócitos Cardíacos/citologia , Miócitos Cardíacos/patologia , Miócitos Cardíacos/ultraestrutura , Proteínas do Tecido Nervoso/sangue , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/sangue , Proteínas Nucleares/química , Proteínas Nucleares/genética , Tamanho da Partícula , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Domínios e Motivos de Interação entre Proteínas , Transporte Proteico , Interferência de RNA , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Supressoras de Tumor/sangue , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/genética
18.
Exp Mol Pathol ; 112: 104326, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31706988

RESUMO

The dual expression of CD5 and MYC protein (DECM) on B-lymphocytes may arise at a specific stage of de novo diffuse large B-cell lymphoma (DLBCL). This study retrospectively reviewed 210 patients with de novo DLBCL at the Affiliated Hospital of Jiangnan University between 2006 and 2017. DECM was significantly correlated with a worse prognosis than that in either the CD5+ or MYC+ or CD5-MYC- patients. Furthermore, patients with DECM showed a similar outcome to MYC+BCL2+ lymphoma patients who have extremely poor survival rates. Multivariate analysis demonstrated that DECM was a significant independent predictor for overall survival (P < .0001) and progression-free survival (P < .0001) in DLBCL. DLBCL patients with DECM showed significantly inferior clinical outcomes compared to the CD5+, MYC+ or CD5-MYC- patients. Combinational therapeutic modalities might be a candidate approach to improve the prognosis of these patients.


Assuntos
Antígenos CD5/genética , Linfoma Difuso de Grandes Células B/genética , Prognóstico , Proteínas Proto-Oncogênicas c-myc/genética , Idoso , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/epidemiologia , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Estudos Retrospectivos , Rituximab/administração & dosagem , Resultado do Tratamento , Vincristina/administração & dosagem
19.
Nanotechnology ; 31(14): 145301, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-31841998

RESUMO

To overcome the shortcoming of drug-loaded nanoparticles, such as high initial burst release and wide size distribution, a novel manufacturing technique for core-shell structure nanoparticle was developed by combining microfluidic chip and electrohydrodynamic atomization. In this study, the mixture solution of the surfactant 1, 2- dipalmitoyl-sn-glycero-3-phosphoglycerol and the polymeric coating material polylactic-glycolic-acid was introduced into the outer microchannel of the microfluidic chip as the particle's shell. And the encapsulated drug paclitaxel was pumped into the inner microchannel as the core. Then, the particles with a nanoscale-size core-shell structure were generated by applying an electric field on the laminar flow which was formed in the microfluidic chip. Operation parameters, including working voltage, carrier material and surfactant concentration as well as liquid flow rates were optimized for nanoparticles generation. The properties of drug-loaded nanoparticles in terms of their particle size, zeta potential and encapsulation efficiency were investigated. Under the optimal experimental conditions, the particle size was approximately 145 nm and encapsulation efficiency reached 92%. Moreover, the drug release of these nanoparticles could be prolonged over a significant period for more than ten days. It can be expected that this innovative approach could provide a useful platform for drug-loaded core-shell nanoparticles developing.


Assuntos
Técnicas Analíticas Microfluídicas/instrumentação , Paclitaxel/síntese química , Sistemas de Liberação de Medicamentos , Nanopartículas , Paclitaxel/química , Tamanho da Partícula , Eletricidade Estática
20.
Zhongguo Zhong Yao Za Zhi ; 45(4): 878-883, 2020 Feb.
Artigo em Zh | MEDLINE | ID: mdl-32237488

RESUMO

In this experiment, the decoction process of famous classical formula Xiebai San was determined by optimizing the particle size of "Cuo san" and investigating the decoction process parameters, such as boiling container, water volume and duration. Xiebai San was taken as an example to explore the study method of the "Cuo san" in the famous classical formulas. The specific chromatogram of Xiebai San and the determination method of glycyrrhizin and glycyrrhizic acid in Xiebai San were established. Different particle sizes of "Cuo san" and decoction parameters were optimized based on the similarity of specific chromatogram, the specific chromatogram's peak area, the content of glycyrrhizin, the content of glycyrrhizic acid and extract yield rate.The particle size of Xiebai San powder was determined to be 2.00-4.75 mm(by four-mesh sieves). The decoction process was determined as follows: put the prescription amount into a ceramic pot, add 420 mL of water, and boil and simmer until the volume is 300 mL.The similarity of specific chromatogram was above 0.9, the specific chromatogram's peak area was larger, the content of glycyrrhizin was 0.12%, the content of glycyrrhizic acid was 0.21%,and the extract yield rate was 15.05%. The finally determined particle size of "Cuo san" can better represent the quality of Xiebai San, and is easy to prepare and suitable for industrial production.This experimental research method can comprehensively investigate the quality of Xiebai San as a whole, the content of active ingredients, and the situation of extract yield.It is a more comprehensive and objective evaluation method, and can provide experimental basis and reference for the study of other "Cuo san" famous classical formulas.


Assuntos
Medicamentos de Ervas Chinesas/química , Ácido Glicirrízico/análise , Tamanho da Partícula , Tecnologia Farmacêutica , Pós
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