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1.
Nat Immunol ; 20(2): 183-194, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30643264

RESUMO

Intestinal stem cells (ISCs) are maintained by stemness signaling for precise modulation of self-renewal and differentiation under homeostasis. However, the way in which intestinal immune cells regulate the self-renewal of ISCs remains elusive. Here we found that mouse and human Lgr5+ ISCs showed high expression of the immune cell-associated circular RNA circPan3 (originating from the Pan3 gene transcript). Deletion of circPan3 in Lgr5+ ISCs impaired their self-renewal capacity and the regeneration of gut epithelium in a manner dependent on immune cells. circPan3 bound mRNA encoding the cytokine IL-13 receptor subunit IL-13Rα1 (Il13ra1) in ISCs to increase its stability, which led to the expression of IL-13Rα1 in ISCs. IL-13 produced by group 2 innate lymphoid cells in the crypt niche engaged IL-13Rα1 on crypt ISCs and activated signaling mediated by IL-13‒IL-13R, which in turn initiated expression of the transcription factor Foxp1. Foxp1 is associated with ß-catenin in rendering its nuclear translocation, which caused activation of the ß-catenin pathway and the maintenance of Lgr5+ ISCs.


Assuntos
Autorrenovação Celular/imunologia , Interleucina-13/metabolismo , Mucosa Intestinal/imunologia , RNA/metabolismo , Células-Tronco/fisiologia , Animais , Proteínas de Transporte/genética , Diferenciação Celular/imunologia , Autorrenovação Celular/genética , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/imunologia , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Feminino , Humanos , Interleucina-13/imunologia , Subunidade alfa1 de Receptor de Interleucina-13/genética , Subunidade alfa1 de Receptor de Interleucina-13/imunologia , Subunidade alfa1 de Receptor de Interleucina-13/metabolismo , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Linfócitos/imunologia , Linfócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Knockout , RNA/genética , RNA/imunologia , RNA Circular , RNA Mensageiro/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Regeneração/genética , Regeneração/imunologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia , beta Catenina/imunologia , beta Catenina/metabolismo
2.
Nat Immunol ; 18(5): 499-508, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28319097

RESUMO

Innate lymphoid cells (ILCs) communicate with other hematopoietic and nonhematopoietic cells to regulate immunity, inflammation and tissue homeostasis. How ILC lineages develop and are maintained remains largely unknown. In this study we observed that a divergent long noncoding RNA (lncRNA), lncKdm2b, was expressed at high levels in intestinal group 3 ILCs (ILC3s). LncKdm2b deficiency in the hematopoietic system led to reductions in the number and effector functions of ILC3s. LncKdm2b expression sustained the maintenance of ILC3s by promoting their proliferation through activation of the transcription factor Zfp292. Mechanistically, lncKdm2b recruited the chromatin organizer Satb1 and the nuclear remodeling factor (NURF) complex onto the Zfp292 promoter to initiate its transcription. Deletion of Zfp292 or Bptf also abrogated the maintenance of ILC3s, leading to susceptibility to bacterial infection. Therefore, our findings reveal that lncRNAs may represent an additional layer of regulation of ILC development and function.


Assuntos
Infecções Bacterianas/genética , Proteínas F-Box/genética , Imunidade Inata , Histona Desmetilases com o Domínio Jumonji/genética , Linfócitos/fisiologia , RNA Longo não Codificante/genética , Animais , Antígenos Nucleares/genética , Diferenciação Celular/genética , Linhagem da Célula/genética , Proliferação de Células/genética , Montagem e Desmontagem da Cromatina , Proteínas de Ligação a DNA/genética , Suscetibilidade a Doenças , Proteínas de Ligação à Região de Interação com a Matriz/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Fatores de Transcrição/genética , Ativação Transcricional
3.
Nature ; 589(7841): 270-275, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33116299

RESUMO

There is an urgent need to create novel models using human disease-relevant cells to study severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) biology and to facilitate drug screening. Here, as SARS-CoV-2 primarily infects the respiratory tract, we developed a lung organoid model using human pluripotent stem cells (hPSC-LOs). The hPSC-LOs (particularly alveolar type-II-like cells) are permissive to SARS-CoV-2 infection, and showed robust induction of chemokines following SARS-CoV-2 infection, similar to what is seen in patients with COVID-19. Nearly 25% of these patients also have gastrointestinal manifestations, which are associated with worse COVID-19 outcomes1. We therefore also generated complementary hPSC-derived colonic organoids (hPSC-COs) to explore the response of colonic cells to SARS-CoV-2 infection. We found that multiple colonic cell types, especially enterocytes, express ACE2 and are permissive to SARS-CoV-2 infection. Using hPSC-LOs, we performed a high-throughput screen of drugs approved by the FDA (US Food and Drug Administration) and identified entry inhibitors of SARS-CoV-2, including imatinib, mycophenolic acid and quinacrine dihydrochloride. Treatment at physiologically relevant levels of these drugs significantly inhibited SARS-CoV-2 infection of both hPSC-LOs and hPSC-COs. Together, these data demonstrate that hPSC-LOs and hPSC-COs infected by SARS-CoV-2 can serve as disease models to study SARS-CoV-2 infection and provide a valuable resource for drug screening to identify candidate COVID-19 therapeutics.


Assuntos
Antivirais/farmacologia , COVID-19/virologia , Colo/citologia , Avaliação Pré-Clínica de Medicamentos/métodos , Pulmão/citologia , Organoides/efeitos dos fármacos , Organoides/virologia , SARS-CoV-2/efeitos dos fármacos , Animais , COVID-19/prevenção & controle , Colo/efeitos dos fármacos , Colo/virologia , Aprovação de Drogas , Feminino , Xenoenxertos/efeitos dos fármacos , Humanos , Técnicas In Vitro , Pulmão/efeitos dos fármacos , Pulmão/virologia , Masculino , Camundongos , Organoides/citologia , Organoides/metabolismo , SARS-CoV-2/genética , Estados Unidos , United States Food and Drug Administration , Tropismo Viral , Internalização do Vírus/efeitos dos fármacos , Tratamento Farmacológico da COVID-19
4.
Nat Methods ; 19(4): 418-428, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35396481

RESUMO

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is one of the deadliest pandemics in history. SARS-CoV-2 not only infects the respiratory tract, but also causes damage to many organs. Organoids, which can self-renew and recapitulate the various physiology of different organs, serve as powerful platforms to model COVID-19. In this Perspective, we overview the current effort to apply both human pluripotent stem cell-derived organoids and adult organoids to study SARS-CoV-2 tropism, host response and immune cell-mediated host damage, and perform drug discovery and vaccine development. We summarize the technologies used in organoid-based COVID-19 research, discuss the remaining challenges and provide future perspectives in the application of organoid models to study SARS-CoV-2 and future emerging viruses.


Assuntos
COVID-19 , Células-Tronco Pluripotentes , Adulto , Humanos , Organoides , Pandemias , SARS-CoV-2
6.
EMBO J ; 39(13): e103786, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32449550

RESUMO

Lgr5+ intestinal stem cells (ISCs) exhibit self-renewal and differentiation features under homeostatic conditions, but the mechanisms controlling Lgr5 + ISC self-renewal remain elusive. Here, we show that the chromatin remodeler SRCAP is highly expressed in mouse intestinal epithelium and ISCs. Srcap deletion impairs both self-renewal of ISCs and intestinal epithelial regeneration. Mechanistically, SRCAP recruits the transcriptional regulator REST to the Prdm16 promoter and induces expression of this transcription factor. By activating PPARδ expression, Prdm16 in turn initiates PPARδ signaling, which sustains ISC stemness. Rest or Prdm16 deficiency abrogates the self-renewal capacity of ISCs as well as intestinal epithelial regeneration. Collectively, these data show that the SRCAP-REST-Prdm16-PPARδ axis is required for self-renewal maintenance of Lgr5 + ISCs.


Assuntos
Adenosina Trifosfatases/metabolismo , Mucosa Intestinal/enzimologia , Transdução de Sinais , Células-Tronco/enzimologia , Adenosina Trifosfatases/genética , Animais , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células HEK293 , Humanos , Mucosa Intestinal/citologia , Camundongos , Camundongos Transgênicos , Regiões Promotoras Genéticas , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Células-Tronco/citologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Circ Res ; 130(7): 963-977, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35255712

RESUMO

BACKGROUND: Increasing evidence suggests that cardiac arrhythmias are frequent clinical features of coronavirus disease 2019 (COVID-19). Sinus node damage may lead to bradycardia. However, it is challenging to explore human sinoatrial node (SAN) pathophysiology due to difficulty in isolating and culturing human SAN cells. Embryonic stem cells (ESCs) can be a source to derive human SAN-like pacemaker cells for disease modeling. METHODS: We used both a hamster model and human ESC (hESC)-derived SAN-like pacemaker cells to explore the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on the pacemaker cells of the heart. In the hamster model, quantitative real-time polymerase chain reaction and immunostaining were used to detect viral RNA and protein, respectively. We then created a dual knock-in SHOX2:GFP;MYH6:mCherry hESC reporter line to establish a highly efficient strategy to derive functional human SAN-like pacemaker cells, which was further characterized by single-cell RNA sequencing. Following exposure to SARS-CoV-2, quantitative real-time polymerase chain reaction, immunostaining, and RNA sequencing were used to confirm infection and determine the host response of hESC-SAN-like pacemaker cells. Finally, a high content chemical screen was performed to identify drugs that can inhibit SARS-CoV-2 infection, and block SARS-CoV-2-induced ferroptosis. RESULTS: Viral RNA and spike protein were detected in SAN cells in the hearts of infected hamsters. We established an efficient strategy to derive from hESCs functional human SAN-like pacemaker cells, which express pacemaker markers and display SAN-like action potentials. Furthermore, SARS-CoV-2 infection causes dysfunction of human SAN-like pacemaker cells and induces ferroptosis. Two drug candidates, deferoxamine and imatinib, were identified from the high content screen, able to block SARS-CoV-2 infection and infection-associated ferroptosis. CONCLUSIONS: Using a hamster model, we showed that primary pacemaker cells in the heart can be infected by SARS-CoV-2. Infection of hESC-derived functional SAN-like pacemaker cells demonstrates ferroptosis as a potential mechanism for causing cardiac arrhythmias in patients with COVID-19. Finally, we identified candidate drugs that can protect the SAN cells from SARS-CoV-2 infection.


Assuntos
COVID-19 , Ferroptose , Humanos , Miócitos Cardíacos/metabolismo , SARS-CoV-2 , Nó Sinoatrial/metabolismo
8.
Macromol Rapid Commun ; 45(12): e2400083, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38537692

RESUMO

Photoactive conjugated microporous polymers (CMPs) as heterogeneous photocatalysts provide a sustainable alternative to classical metal-based semiconductor photosensitizers. However, previously reported CMPs are typically synthesized through metal catalyzed coupling reactions, which bears product separation, but also increases the price of materials. Herein, a new type of sp2 carbon linked DCM-CMPs are successfully designed and synthesized by organic base catalyzed Knoevenagel reaction using 2,6-Dimethyl-4H-pyran-4-ylidene-malononitrile and aromatic polyaldehydes as monomers. The new polymers feature inherent porosity, excellent stability, and fully π-conjugated skeleton with broad visible-light absorption. They effectively induce the synthesis of benzimidazole compounds under light irradiation, and exhibit wide substrate adaptability with outstanding recyclability.


Assuntos
Nitrilas , Processos Fotoquímicos , Polímeros , Catálise , Nitrilas/química , Porosidade , Polímeros/química , Polímeros/síntese química , Estrutura Molecular , Luz , Piranos/química , Piranos/síntese química , Propriedades de Superfície , Benzimidazóis/química , Tamanho da Partícula
9.
Phytopathology ; 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39348563

RESUMO

Plant diseases impact the production of all kinds of crops, resulting in significant economic losses worldwide. Timely and accurate detection of plant pathogens is crucial for surveillance and management of plant diseases. In recent years, loop-mediated isothermal amplification (LAMP) has become a popular method for pathogen detection and disease diagnosis due to the advantages of its simple instrument requirement and constant reaction temperature. In this review, we provide an overview of current research on LAMP, including the reaction system, design of primers, selection of target regions, visualization of amplicons, and application of LAMP on the detection of all major groups of plant pathogens. We also discuss plant pathogens for which LAMP is yet to be developed, potential improvements of plant disease diagnosis, and disadvantages that need to be considered.

10.
Int J Mol Sci ; 25(19)2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39408886

RESUMO

The lateral organ boundaries domain (LBD) genes, as the plant-specific transcription factor family, play a crucial role in controlling plant architecture and stress tolerance. However, the functions of AhLBD genes in the peanut plant (Arachis hypogea L.) remain unclear. In this study, 73 AhLBDs were identified in the peanut plant and divided into three groups by phylogenetic tree analysis. Gene structure and conserved protein motif analysis supported the evolutionary conservation of AhLBDs. Tandem and segment duplications contributed to the expansion of AhLBDs. The evolutionary relationship analysis of LBD gene family between A. hypogaea and four other species indicated that the peanut plant had a close relationship with the soybean plant. AhLBDs played a very important role in response to growth and development as well as abiotic stress. Furthermore, gene expression profiling and real-time quantitative qRT-PCR analysis showed that AhLBD16, AhLBD33, AhLBD67, and AhLBD72 were candidate genes for salt stress, while AhLBD24, AhLBD33, AhLBD35, AhLBD52, AhLBD67, and AhLBD71 were candidate genes for drought stress. Our subcellular localization experiment revealed that AhLBD24, AhLBD33, AhLBD67, and AhLBD71 were located in the nucleus. Heterologous overexpression of AhLBD33 and AhLBD67 in Arabidopsis significantly enhanced tolerance to salt stress. Our results provide a theoretical basis and candidate genes for studying the molecular mechanism for abiotic stress in the peanut plant.


Assuntos
Arachis , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas , Estresse Fisiológico , Fatores de Transcrição , Arachis/genética , Arachis/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Perfilação da Expressão Gênica , Família Multigênica , Estudo de Associação Genômica Ampla , Genoma de Planta , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento
12.
J Environ Sci (China) ; 125: 362-375, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36375921

RESUMO

Frequent occurrence of harmful algal blooms has already threatened aquatic life and human health. In the present study, floating BiOCl0.6I0.4/ZnO photocatalyst was synthesized in situ by water bath method, and and applied in inactivation of Microcystis aeruginosa under visible light. The composition, morphology, chemical states, optical properties of the photocatalyst were also characterized. The results showed that BiOCl0.6I0.4 exhibited laminated nanosheet structure with regular shape, and the light response range of the composite BZ/EP-3 (BiOCl0.6I0.4/ZnO/EP-3) was tuned from 582 to 638 nm. The results of photocatalytic experiments indicated that BZ/EP-3 composite had stronger photocatalytic activity than a single BiOCl0.6I0.4 and ZnO, and the removal rate of chlorophyll a was 89.28% after 6 hr of photocatalytic reaction. The photosynthetic system was destroyed and cell membrane of algae ruptured under photocatalysis, resulting in the decrease of phycobiliprotein components and the release of a large number of ions (K+, Ca2+ and Mg2+). Furthermore, active species trapping experiment determined that holes (h+) and superoxide radicals (·O2-) were the main active substance for the inactivation of algae, and the p-n mechanism of photocatalyst was proposed. Overall, BZ/EP-3 showed excellent algal removal ability under visible light, providing fundamental theories for practical algae pollution control.


Assuntos
Microcystis , Óxido de Zinco , Humanos , Clorofila A , Luz , Proliferação Nociva de Algas
13.
EMBO J ; 37(8)2018 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-29535137

RESUMO

Divergent long noncoding RNAs (lncRNAs) represent a major lncRNA biotype in mouse and human genomes. The biological and molecular functions of the divergent lncRNAs remain largely unknown. Here, we show that lncKdm2b, a divergent lncRNA for Kdm2b gene, is conserved among five mammalian species and highly expressed in embryonic stem cells (ESCs) and early embryos. LncKdm2b knockout impairs ESC self-renewal and causes early embryonic lethality. LncKdm2b can activate Zbtb3 by promoting the assembly and ATPase activity of Snf2-related CREBBP activator protein (SRCAP) complex in trans Zbtb3 potentiates the ESC self-renewal in a Nanog-dependent manner. Finally, Zbtb3 deficiency impairs the ESC self-renewal and early embryonic development. Therefore, our findings reveal that lncRNAs may represent an additional layer of the regulation of ESC self-renewal and early embryogenesis.


Assuntos
Proteínas de Ligação a DNA/genética , Células-Tronco Embrionárias/metabolismo , RNA Longo não Codificante/genética , Animais , Desenvolvimento Embrionário , Humanos , Camundongos Knockout
14.
Proc Natl Acad Sci U S A ; 116(40): 19917-19923, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31527241

RESUMO

Chromosomal translocations of MLL1 (Mixed Lineage Leukemia 1) yield oncogenic chimeric proteins containing the N-terminal portion of MLL1 fused with distinct partners. The MLL1-AF10 fusion causes leukemia through recruiting the H3K79 histone methyltransferase DOT1L via AF10's octapeptide and leucine zipper (OM-LZ) motifs. Yet, the precise interaction sites in DOT1L, detailed interaction modes between AF10 and DOT1L, and the functional configuration of MLL1-AF10 in leukeomogenesis remain unknown. Through a combined approach of structural and functional analyses, we found that the LZ domain of AF10 interacts with the coiled-coil domains of DOT1L through a conserved binding mode and discovered that the C-terminal end of the LZ domain and the OM domain of AF10 mediate the formation of a DOT1L-AF10 octamer via tetramerization of the binary complex. We reveal that the oligomerization ability of the DOT1L-AF10 complex is essential for MLL1-AF10's leukemogenic function. These findings provide insights into the molecular basis of pathogenesis by MLL1 rearrangements.


Assuntos
Regulação Leucêmica da Expressão Gênica , Histona-Lisina N-Metiltransferase/metabolismo , Leucemia/metabolismo , Proteína de Leucina Linfoide-Mieloide/metabolismo , Fatores de Transcrição/metabolismo , Núcleo Celular/metabolismo , Transformação Celular Neoplásica , Escherichia coli/metabolismo , Humanos , Zíper de Leucina , Leucemia/patologia , Mutação , Proteínas de Fusão Oncogênica/metabolismo , Ligação Proteica , Domínios Proteicos , Mapeamento de Interação de Proteínas , Multimerização Proteica , Estrutura Secundária de Proteína
15.
Plant Dis ; 106(1): 260-265, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34402633

RESUMO

Phoma macdonaldii, the causal agent of sunflower black stem, severely affects sunflower yield and quality. A rapid and sensitive detection method is necessary for diagnosis of this disease. In this study, a loop-mediated isothermal amplification (LAMP) assay was developed for rapid detection of the pathogen from diseased sunflower tissues. The LAMP primers were designed to target the rDNA region of the fungus. The reaction condition was optimized to 60°C water baths for 45 min. The detection limit of the LAMP assay was 100 fg DNA or 10 conidia/g seeds. The LAMP assay was validated by detecting P. macdonaldii from infected sunflower tissue samples, including leaves, stems, and seeds, and applying to seed samples randomly collected from sunflower fields. This LAMP assay will be useful for estimating disease prevalence and implementing sustainable management of sunflower black stem.


Assuntos
Ascomicetos , Helianthus , Ascomicetos/genética , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico
16.
AAPS PharmSciTech ; 22(1): 15, 2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33389269

RESUMO

The present study endeavored to develop orodispersible films (ODFs) containing 30 mg racecadotril for pediatric use, which focuses on improving the compliance of pediatric patients and reducing risk of choking. The challenge of this study is to prepare high drug loading ODFs with successful mechanical and physicochemical properties. Compatibilities between drug and different polymers (hydroxypropyl methylcellulose, HPMC; polyvinyl alcohol, PVA; low-substituted hydroxypropyl cellulose, L-HPC; pullulan, PU) were investigated to select stable and safe film-forming polymers. Afterwards, the study explored the maximum amount of racecadotril incorporated into PVA films and PU films. Subsequently, disintegrant (Lycoat RS720, 4-10%, w/w) and plasticizers (glycerol, 2-6%, w/w) were investigated to reduce disintegration time of PVA films and enhance the flexibility of PU films, respectively. Formulation characteristics (appearance, tensile strength, percent elongation, disintegration time, drug content, weight, thickness, pH value, moisture content, moisture uptake, and Q5min) of prepared ODFs were examined to obtain the optimal compositions of racecadotril ODFs. Differential scanning calorimetry (DSC) study, powder X-ray diffraction (XRD) study, Fourier transform infrared (FTIR) study, comparative in vitro dissolution study, and pharmacokinetic study in Beagle dogs of optimized racecadotril ODFs were then conducted. Eventually, ODFs containing 50% racecadotril, 38% PVA, 7% Lycoat RS720, 2% sucralose, 2% apricot, and 1% titanium dioxide could achieve desirable mechanical properties, disintegrating within a few seconds and releasing more than 85% drug within 5 min in four dissolution media. An in vivo study showed optimized racecadotril ODF and Hidrasec were bioequivalent in Beagle dogs. In summary, ODFs containing 30 mg racecadotril were successfully prepared by solvent casting method, and it was suitable for the administration to the pediatric patients.


Assuntos
Antidiarreicos/farmacologia , Tiorfano/análogos & derivados , Resinas Acrílicas/química , Administração Oral , Antidiarreicos/administração & dosagem , Varredura Diferencial de Calorimetria , Celulose/análogos & derivados , Criança , Formas de Dosagem , Excipientes/química , Humanos , Derivados da Hipromelose/química , Técnicas In Vitro , Pediatria , Álcool de Polivinil/química , Pós , Solubilidade , Solventes/química , Tiorfano/administração & dosagem , Tiorfano/farmacologia , Difração de Raios X
17.
AAPS PharmSciTech ; 21(7): 245, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32856178

RESUMO

The purpose of this study was to investigate the impacts of the formulation parameters on the pharmacokinetics and bioequivalence of risperidone orodispersible film (ODF) using physiologically based pharmacokinetic model. The pharmacokinetic profiles of two risperidone ODFs, which exhibit different in vitro dissolution, were examined in Beagle dogs after supralingual administration. Subsequently, a physiologically based pharmacokinetic (PBPK) model was constructed to evaluate the in vivo performance of risperidone ODF. The parameter sensitivity analysis (PSA) was used to access the impacts of formulation parameters on the pharmacokinetics of risperidone. Moreover, the validated PBPK model was applied to predict human pharmacokinetic profiles and examine the bioequivalence of these two ODFs. These two ODFs displayed similar risperidone pharmacokinetic profiles in dogs. The parameter sensitivity analysis indicated that the changes in the solubility, particle size, particle density, and diffusion coefficient did not have obvious influence on the in vivo properties of risperidone ODF. Alternation of the in vitro complete dissolution time in water from 15 to 30 min led to a 30% decrease in Cmax and 20% of increase in Tmax. AUC0-∞ would be decreased if risperidone was not fully released within 1 h. As both ODFs completely released risperidone within 15 min, the difference in the extent of in vivo absorption, intestinal regional absorption location, and plasma concentration-time curves between these two ODFs was almost negligible. Consequently, a bioequivalence was foreseen in humans. The in vitro cumulative dissolution percentage in water at 15 min was found to be the major determinant on the in vivo properties of risperidone ODF. PBPK modeling appears to be an innovative strategy to guide the development of risperidone ODF.


Assuntos
Absorção Intestinal/efeitos dos fármacos , Absorção Intestinal/fisiologia , Modelos Biológicos , Risperidona/administração & dosagem , Risperidona/farmacocinética , Administração Oral , Animais , Cães , Feminino , Humanos , Masculino , Tamanho da Partícula , Risperidona/química , Antagonistas da Serotonina/administração & dosagem , Antagonistas da Serotonina/química , Antagonistas da Serotonina/farmacocinética , Solubilidade , Equivalência Terapêutica
18.
J Hepatol ; 70(5): 918-929, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30582981

RESUMO

BACKGROUND & AIMS: Liver cancer is the second leading cause of cancer death worldwide. Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer in adults. The aim of this study was to define the role of the long non-coding RNA lncHDAC2 in the tumorigenesis of HCC. METHODS: CD13+CD133+ cells (hereafter called liver cancer stem cells [CSCs]) and CD13-CD133- cells (referred to as non-CSCs) were sorted from 3 primary HCC tumor tissues and followed by transcriptome microarray. The expression and function of lncHDAC2 were further assessed by northern blot, sphere formation and xenograft tumor models. RESULTS: LncHDAC2 is highly expressed in HCC tumors and liver CSCs. LncHDAC2 promotes the self-renewal of liver CSCs and tumor propagation. In liver CSCs, lncHDAC2 recruits the NuRD complex onto the promoter of PTCH1 to inhibit its expression, leading to activation of Hedgehog signaling. Moreover, HDAC2 expression levels are positively related to HCC severity and PTCH1 levels are negatively related to HCC severity. Additionally, the Smo inhibitor cyclopamine was shown to impair the self-renewal of liver CSCs and suppress tumor propagation. CONCLUSION: Our findings reveal that lncHDAC2 promotes the self-renewal of liver CSCs and tumor propagation by activating the Hedgehog signaling pathway. Downregulating lncHDAC2 is a promising antitumor strategy in HCC. LAY SUMMARY: Liver cancer stem cells harbor high tumor-initiating potential and confer resistance to typical therapies, but the mechanism underlying their self-renewal remains elusive. LncHDAC2 augments the self-renewal of these cells, promoting tumor propagation. In liver cancer stem cells, lncHDAC2 activates Hedgehog signaling to initiate liver tumorigenesis. Therefore, lncHDAC2 and the Hedgehog signaling pathway may serve as biomarkers and potential drug targets for hepatocellular carcinoma.


Assuntos
Autorrenovação Celular , Proteínas Hedgehog/fisiologia , Histona Desacetilase 2/genética , Neoplasias Hepáticas/patologia , Células-Tronco Neoplásicas/fisiologia , RNA Longo não Codificante/fisiologia , Transdução de Sinais , Linhagem Celular Tumoral , Humanos , Receptor Patched-1/genética , Regiões Promotoras Genéticas , Transdução de Sinais/fisiologia
19.
J Immunol ; 194(3): 1292-303, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25548215

RESUMO

NK cells play a pivotal role in innate immune responses against pathogenic infections. However, the underlying mechanisms driving defined NK functions remain largely elusive. In this study, we identified a novel endoplasmic reticulum (ER) membrane protein, ER adaptor protein (ERAdP), which is constitutively expressed in human and mouse NK cells. ERAdP is expressed at low levels in peripheral NK cells of hepatitis B virus-associated hepatocellular carcinoma patients. We show that ERAdP initiates NK cell activation through the NF-κB pathway. Notably, ERAdP interacts with ubiquitin-conjugating enzyme 13 (Ubc13) to potentiate its charging activity. Thus, ERAdP augments Ubc13-mediated NF-κB essential modulator ubiquitination to trigger the Ubc13-mediated NF-κB pathway, leading to NK cell activation. Finally, ERAdP transgenic mice display hyperactivated NK cells that are more resistant to pathogenic infections. Therefore, understanding the mechanism of ERAdP-mediated NK cell activation will provide strategies for treatment of infectious diseases.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Ativação Linfocitária/imunologia , Proteínas de Membrana/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Enzimas de Conjugação de Ubiquitina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Citotoxicidade Imunológica/genética , Retículo Endoplasmático/metabolismo , Ativação Enzimática , Expressão Gênica , Humanos , Quinase I-kappa B/metabolismo , Interferon gama/biossíntese , Proteínas de Membrana/genética , Camundongos , Camundongos Transgênicos , Ligação Proteica , Ubiquitinação
20.
ChemSusChem ; 17(11): e202400315, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38538541

RESUMO

Covalent organic framework (COF) nanosheets have recently garnered great attention as a new class of functional materials. As one of the sustainable processes, however, the photocatalytic organic synthesis in water has not been investigated using COF nanosheets as a photocatalyst to date. Herein, we reported the synthesis of a fully conjugated COF nanosheets with carboxyl functional group through a cooperative strategy of chemical exfoliation and group transformation. The new COF nanosheets was found to be an efficient heterogeneous photocatalyst for a wide range of organic synthesis including selective oxidation of sulfides and oxidative coupling of benzylamines in water under visible-light illumination. This work contributes a new roadmap for the design and synthesis of functional COF-based nanosheets, but also further extends the application boundary of the ultrathin COF nanosheets.

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