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1.
Cell ; 184(3): 775-791.e14, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33503446

RESUMO

The molecular pathology of multi-organ injuries in COVID-19 patients remains unclear, preventing effective therapeutics development. Here, we report a proteomic analysis of 144 autopsy samples from seven organs in 19 COVID-19 patients. We quantified 11,394 proteins in these samples, in which 5,336 were perturbed in the COVID-19 patients compared to controls. Our data showed that cathepsin L1, rather than ACE2, was significantly upregulated in the lung from the COVID-19 patients. Systemic hyperinflammation and dysregulation of glucose and fatty acid metabolism were detected in multiple organs. We also observed dysregulation of key factors involved in hypoxia, angiogenesis, blood coagulation, and fibrosis in multiple organs from the COVID-19 patients. Evidence for testicular injuries includes reduced Leydig cells, suppressed cholesterol biosynthesis, and sperm mobility. In summary, this study depicts a multi-organ proteomic landscape of COVID-19 autopsies that furthers our understanding of the biological basis of COVID-19 pathology.


Assuntos
COVID-19/metabolismo , Regulação da Expressão Gênica , Proteoma/biossíntese , Proteômica , SARS-CoV-2/metabolismo , Autopsia , COVID-19/patologia , COVID-19/terapia , Feminino , Humanos , Masculino , Especificidade de Órgãos
2.
Cell ; 182(1): 59-72.e15, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32492406

RESUMO

Early detection and effective treatment of severe COVID-19 patients remain major challenges. Here, we performed proteomic and metabolomic profiling of sera from 46 COVID-19 and 53 control individuals. We then trained a machine learning model using proteomic and metabolomic measurements from a training cohort of 18 non-severe and 13 severe patients. The model was validated using 10 independent patients, 7 of which were correctly classified. Targeted proteomics and metabolomics assays were employed to further validate this molecular classifier in a second test cohort of 19 COVID-19 patients, leading to 16 correct assignments. We identified molecular changes in the sera of COVID-19 patients compared to other groups implicating dysregulation of macrophage, platelet degranulation, complement system pathways, and massive metabolic suppression. This study revealed characteristic protein and metabolite changes in the sera of severe COVID-19 patients, which might be used in selection of potential blood biomarkers for severity evaluation.


Assuntos
Infecções por Coronavirus/sangue , Metabolômica , Pneumonia Viral/sangue , Proteômica , Adulto , Aminoácidos/metabolismo , Biomarcadores/sangue , COVID-19 , Análise por Conglomerados , Infecções por Coronavirus/fisiopatologia , Feminino , Humanos , Metabolismo dos Lipídeos , Aprendizado de Máquina , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/fisiopatologia , Índice de Gravidade de Doença
3.
Nat Immunol ; 23(4): 594-604, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35354951

RESUMO

While T cell receptor (TCR) αß+CD8α+CD8ß- intraepithelial lymphocytes (CD8αα+ IELs) differentiate from thymic IEL precursors (IELps) and contribute to gut homeostasis, the transcriptional control of their development remains poorly understood. In the present study we showed that mouse thymocytes deficient for the transcription factor leukemia/lymphoma-related factor (LRF) failed to generate TCRαß+CD8αα+ IELs and their CD8ß-expressing counterparts, despite giving rise to thymus and spleen CD8αß+ T cells. LRF-deficient IELps failed to migrate to the intestine and to protect against T cell-induced colitis, and had impaired expression of the gut-homing integrin α4ß7. Single-cell RNA-sequencing found that LRF was necessary for the expression of genes characteristic of the most mature IELps, including Itgb7, encoding the ß7 subunit of α4ß7. Chromatin immunoprecipitation and gene-regulatory network analyses both defined Itgb7 as an LRF target. Our study identifies LRF as an essential transcriptional regulator of IELp maturation in the thymus and subsequent migration to the intestinal epithelium.


Assuntos
Linfócitos Intraepiteliais , Leucemia , Linfoma , Animais , Antígenos CD8/genética , Antígenos CD8/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Cadeias beta de Integrinas , Mucosa Intestinal/metabolismo , Linfócitos Intraepiteliais/metabolismo , Leucemia/metabolismo , Linfoma/metabolismo , Camundongos , Camundongos Knockout , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Fatores de Transcrição/metabolismo
4.
Nature ; 618(7963): 102-109, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37225985

RESUMO

Parasitic nematodes are a major threat to global food security, particularly as the world amasses 10 billion people amid limited arable land1-4. Most traditional nematicides have been banned owing to poor nematode selectivity, leaving farmers with inadequate means of pest control4-12. Here we use the model nematode Caenorhabditis elegans to identify a family of selective imidazothiazole nematicides, called selectivins, that undergo cytochrome-p450-mediated bioactivation in nematodes. At low parts-per-million concentrations, selectivins perform comparably well with commercial nematicides to control root infection by Meloidogyne incognita, a highly destructive plant-parasitic nematode. Tests against numerous phylogenetically diverse non-target systems demonstrate that selectivins are more nematode-selective than most marketed nematicides. Selectivins are first-in-class bioactivated nematode controls that provide efficacy and nematode selectivity.


Assuntos
Antinematódeos , Tylenchoidea , Animais , Humanos , Antinematódeos/química , Antinematódeos/metabolismo , Antinematódeos/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/metabolismo , Tylenchoidea/efeitos dos fármacos , Tylenchoidea/metabolismo , Tiazóis/química , Tiazóis/metabolismo , Tiazóis/farmacologia , Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/parasitologia , Doenças das Plantas , Especificidade da Espécie , Especificidade por Substrato
5.
Immunity ; 51(3): 465-478.e6, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31422869

RESUMO

The generation of high-affinity neutralizing antibodies, the objective of most vaccine strategies, occurs in B cells within germinal centers (GCs) and requires rate-limiting "help" from follicular helper CD4+ T (Tfh) cells. Although Tfh differentiation is an attribute of MHC II-restricted CD4+ T cells, the transcription factors driving Tfh differentiation, notably Bcl6, are not restricted to CD4+ T cells. Here, we identified a requirement for the CD4+-specific transcription factor Thpok during Tfh cell differentiation, GC formation, and antibody maturation. Thpok promoted Bcl6 expression and bound to a Thpok-responsive region in the first intron of Bcl6. Thpok also promoted the expression of Bcl6-independent genes, including the transcription factor Maf, which cooperated with Bcl6 to mediate the effect of Thpok on Tfh cell differentiation. Our findings identify a transcriptional program that links the CD4+ lineage with Tfh differentiation, a limiting factor for efficient B cell responses, and suggest avenues to optimize vaccine generation.


Assuntos
Diferenciação Celular/imunologia , Proteínas Proto-Oncogênicas c-bcl-6/imunologia , Proteínas Proto-Oncogênicas c-maf/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Fatores de Transcrição/imunologia , Transcrição Gênica/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Feminino , Regulação da Expressão Gênica/imunologia , Centro Germinativo/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL
6.
Nat Methods ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965442

RESUMO

Dynamic imaging of genomic loci is key for understanding gene regulation, but methods for imaging genomes, in particular non-repetitive DNAs, are limited. We developed CRISPRdelight, a DNA-labeling system based on endonuclease-deficient CRISPR-Cas12a (dCas12a), with an engineered CRISPR array to track DNA location and motion. CRISPRdelight enables robust imaging of all examined 12 non-repetitive genomic loci in different cell lines. We revealed the confined movement of the CCAT1 locus (chr8q24) at the nuclear periphery for repressed expression and active motion in the interior nucleus for transcription. We uncovered the selective repositioning of HSP gene loci to nuclear speckles, including a remarkable relocation of HSPH1 (chr13q12) for elevated transcription during stresses. Combining CRISPR-dCas12a and RNA aptamers allowed multiplex imaging of four types of satellite DNA loci with a single array, revealing their spatial proximity to the nucleolus-associated domain. CRISPRdelight is a user-friendly and robust system for imaging and tracking genomic dynamics and regulation.

7.
PLoS Pathog ; 20(1): e1011918, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38241414

RESUMO

Bacterial persister cells, a sub-population of dormant phenotypic variants highly tolerant to antibiotics, present a significant challenge for infection control. Investigating the mechanisms of antibiotic persistence is crucial for developing effective treatment strategies. Here, we found a significant association between tolerance frequency and previous infection history in bovine mastitis. Previous S. aureus infection led to S. aureus tolerance to killing by rifampicin in subsequent infection in vivo and in vitro. Actually, the activation of trained immunity contributed to rifampicin persistence of S. aureus in secondary infection, where it reduced the effectiveness of antibiotic treatment and increased disease severity. Mechanically, we found that S. aureus persistence was mediated by the accumulation of fumarate provoked by trained immunity. Combination therapy with metformin and rifampicin promoted eradication of persisters and improved the severity of recurrent S. aureus infection. These findings provide mechanistic insight into the relationship between trained immunity and S. aureus persistence, while providing proof of concept that trained immunity is a therapeutic target in recurrent bacterial infections involving persistent pathogens.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Animais , Feminino , Bovinos , Staphylococcus aureus/fisiologia , Rifampina/farmacologia , Rifampina/uso terapêutico , Imunidade Treinada , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Bactérias
8.
Nature ; 588(7837): 284-289, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33239781

RESUMO

Genetic diversity is key to crop improvement. Owing to pervasive genomic structural variation, a single reference genome assembly cannot capture the full complement of sequence diversity of a crop species (known as the 'pan-genome'1). Multiple high-quality sequence assemblies are an indispensable component of a pan-genome infrastructure. Barley (Hordeum vulgare L.) is an important cereal crop with a long history of cultivation that is adapted to a wide range of agro-climatic conditions2. Here we report the construction of chromosome-scale sequence assemblies for the genotypes of 20 varieties of barley-comprising landraces, cultivars and a wild barley-that were selected as representatives of global barley diversity. We catalogued genomic presence/absence variants and explored the use of structural variants for quantitative genetic analysis through whole-genome shotgun sequencing of 300 gene bank accessions. We discovered abundant large inversion polymorphisms and analysed in detail two inversions that are frequently found in current elite barley germplasm; one is probably the product of mutation breeding and the other is tightly linked to a locus that is involved in the expansion of geographical range. This first-generation barley pan-genome makes previously hidden genetic variation accessible to genetic studies and breeding.


Assuntos
Cromossomos de Plantas/genética , Genoma de Planta/genética , Hordeum/genética , Internacionalidade , Mutação , Melhoramento Vegetal , Inversão Cromossômica/genética , Mapeamento Cromossômico , Loci Gênicos/genética , Genótipo , Hordeum/classificação , Polimorfismo Genético/genética , Padrões de Referência , Banco de Sementes , Inversão de Sequência , Sequenciamento Completo do Genoma
9.
Exp Cell Res ; 438(1): 114052, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38636651

RESUMO

Trained immunity is mechanistically defined as the metabolically and epigenetically mediated long-term functional adaptation of the innate immune system, characterized by a heightened response to a secondary stimulation. Given appropriate activation, trained immunity represents an attractive anti-infective therapeutic target. Nevertheless, excessive immune response and subsequent inflammatory cascades may contribute to pathological tissue damage, indicating that the negative impacts of trained immunity appear to be significant. In this study, we show that innate immune responses such as the production of extracellular traps, pro-inflammatory cytokines, and autophagy-related proteins were markedly augmented in trained BMDMs. Furthermore, heat-killed C. albicans priming promotes the activation of the AIM2 inflammasome, and AIM2-/- mice exhibit impaired memory response induced by heat-killed C. albicans. Therefore, we establish that the AIM2 inflammasome is involved in trained immunity and emerges as a promising therapeutic target for potentially deleterious effects. Dihydroartemisinin can inhibit the memory response induced by heat-killed C. albicans through modulation of mTOR signaling and the AIM2 inflammasome. The findings suggest that dihydroartemisinin can reduce the induction of trained immunity by heat-killed C. albicans in C57BL/6 mice. Dihydroartemisinin is one such therapeutic intervention that has the potential to treat of diseases characterized by excessive trained immunity.


Assuntos
Artemisininas , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Serina-Treonina Quinases TOR , Animais , Serina-Treonina Quinases TOR/metabolismo , Transdução de Sinais/efeitos dos fármacos , Camundongos , Artemisininas/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Candida albicans/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Inflamassomos/metabolismo , Inflamassomos/efeitos dos fármacos , Camundongos Knockout , Imunidade Treinada
10.
J Infect Dis ; 229(1): 117-121, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-37565805

RESUMO

Using a prospective, observational cohort study during the post-"dynamic COVID-zero" wave in China, we estimated short-term relative effectiveness against Omicron BA.5 infection of inhaled aerosolized adenovirus type 5-vectored ancestral strain coronavirus disease 2019 (COVID-19) vaccine as a second booster dose approximately 1 year after homologous boosted primary series of inactivated COVID-19 vaccine compared with no second booster. Participants reported nucleic acid or antigen test results weekly until they tested positive or completed predesignated follow-up. After excluding participants infected <14 days after study entry, relative effectiveness among the 6576 participants was 61% in 18- to 59-year-olds and 38% in ≥60-year-olds and was sustained for 12 weeks.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , COVID-19/prevenção & controle , Estudos Prospectivos , Eficácia de Vacinas , China/epidemiologia , Adenoviridae/genética
11.
Gastroenterology ; 165(3): 629-646, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37247644

RESUMO

BACKGROUND & AIMS: Hyperactivation of ribosome biogenesis leads to hepatocyte transformation and plays pivotal roles in hepatocellular carcinoma (HCC) development. We aimed to identify critical ribosome biogenesis proteins that are overexpressed and crucial in HCC progression. METHODS: HEAT repeat containing 1 (HEATR1) expression and clinical correlations were analyzed using The Cancer Genome Atlas and Gene Expression Omnibus databases and further evaluated by immunohistochemical analysis of an HCC tissue microarray. Gene expression was knocked down by small interfering RNA. HEATR1-knockdown cells were subjected to viability, cell cycle, and apoptosis assays and used to establish subcutaneous and orthotopic tumor models. Chromatin immunoprecipitation and quantitative polymerase chain reaction were performed to detect the association of candidate proteins with specific DNA sequences. Endogenous coimmunoprecipitation combined with mass spectrometry was used to identify protein interactions. We performed immunoblot and immunofluorescence assays to detect and localize proteins in cells. The nucleolus ultrastructure was detected by transmission electron microscopy. Click-iT (Thermo Fisher Scientific) RNA imaging and puromycin incorporation assays were used to measure nascent ribosomal RNA and protein synthesis, respectively. Proteasome activity, 20S proteasome foci formation, and protein stability were evaluated in HEATR1-knockdown HCC cells. RESULTS: HEATR1 was the most up-regulated gene in a set of ribosome biogenesis mediators in HCC samples. High expression of HEATR1 was associated with poor survival and malignant clinicopathologic features in patients with HCC and contributed to HCC growth in vitro and in vivo. HEATR1 expression was regulated by the transcription factor specificity protein 1, which can be activated by insulin-like growth factor 1-mammalian target of rapamycin complex 1 signaling in HCC cells. HEATR1 localized predominantly in the nucleolus, bound to ribosomal DNA, and was associated with RNA polymerase I transcription/processing factors. Knockdown of HEATR1 disrupted ribosomal RNA biogenesis and impaired nascent protein synthesis, leading to reduced cytoplasmic proteasome activity and inhibitory-κB/nuclear factor-κB signaling. Moreover, HEATR1 knockdown induced nucleolar stress with increased nuclear proteasome activity and inactivation of the nucleophosmin 1-MYC axis. CONCLUSIONS: Our study revealed that HEATR1 is up-regulated by insulin-like growth factor 1-mammalian target of rapamycin complex 1-specificity protein 1 signaling in HCC and functions as a crucial regulator of ribosome biogenesis and proteome homeostasis to promote HCC development.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Homeostase , Temperatura Alta , Fator de Crescimento Insulin-Like I/genética , Neoplasias Hepáticas/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Complexo de Endopeptidases do Proteassoma/genética , Proteoma/metabolismo , Ribossomos/metabolismo , Ribossomos/patologia , RNA Ribossômico/genética , RNA Ribossômico/metabolismo
12.
Anal Chem ; 96(10): 4129-4137, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38469639

RESUMO

Long-term continuous imaging of endogenous HClO burst is of great importance for the elucidation of various physiological or pathological processes. However, most of the currently reported HClO probes have failed to achieve this goal due to their insufficient photobleaching resistance under a laser source. Herein, a highly stable ratiometric probe, HFTC-HClO 1, which is capable of continuously monitoring endogenous HClO burst over a long period of time, has been judiciously developed. Briefly, the de novo development of HFTC-HClO 1 mainly involved three main steps: (1) novel coumarins (HFTC 1-5) were designed and synthesized; (2) the most stable scaffold, HFTC 3, was selected through dye screening and cell imaging validation; and (3) based on HFTC 3, three candidate HClO probes were constructed, and HFTC-HClO 1 was finally selected due to its superior sensing properties toward HClO. Furthermore, HFTC-HClO 1 can quantitatively measure HClO levels in various real samples with excellent recovery (>90.4%), and the use of HFTC-HClO 1-coated test strips for qualitative analysis of HClO in real samples was also achieved. In addition, the application of HFTC-HClO 1 for long-term continuous monitoring of intracellular HClO burst was successfully demonstrated. Significantly, HFTC-HClO 1 was able to visualize HClO generated in the rheumatoid arthritis mouse model.


Assuntos
Corantes Fluorescentes , Ácido Hipocloroso , Camundongos , Animais , Ácido Hipocloroso/análise , Microscopia de Fluorescência/métodos , Imagem Óptica/métodos , Cumarínicos
13.
Anal Chem ; 96(18): 7082-7090, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38652135

RESUMO

Parkinson's disease (PD) represents the second most widespread neurodegenerative disease, and early monitoring and diagnosis are urgent at present. Tyrosine hydroxylase (TH) is a key enzyme for producing dopamine, the levels of which can serve as an indicator for assessing the severity and progression of PD. This renders the specific detection and visualization of TH a strategically vital way to meet the above demands. However, a fluorescent probe for TH monitoring is still missing. Herein, three rationally designed wash-free ratiometric fluorescent probes were proposed. Among them, TH-1 exhibited ideal photophysical properties and specific dual-channel bioimaging of TH activity in SH-SY5Y nerve cells. Moreover, the probe allowed for in vivo imaging of TH activity in zebrafish brain and living striatal slices of mice. Overall, the ratiometric fluorescent probe TH-1 could serve as a potential tool for real-time monitoring of PD in complex biosystems.


Assuntos
Corantes Fluorescentes , Tirosina 3-Mono-Oxigenase , Peixe-Zebra , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Tirosina 3-Mono-Oxigenase/metabolismo , Tirosina 3-Mono-Oxigenase/análise , Animais , Camundongos , Humanos , Imagem Óptica , Linhagem Celular Tumoral , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismo
14.
Anal Chem ; 96(29): 11915-11922, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39007441

RESUMO

G-quadruplex structures within the nuclear genome (nG4) is an important regulatory factor, while the function of G4 in the mitochondrial genome (mtG4) still needs to be explored, especially in human sperms. To gain a better understanding of the relationship between mtG4 and mitochondrial function, it is crucial to develop excellent probes that can selectively visualize and track mtG4 in both somatic cells and sperms. Herein, based on our previous research on purine frameworks, we attempted for the first time to extend the conjugated structure from the C-8 site of purine skeleton and discovered that the purine derivative modified by the C-8 aldehyde group is an ideal platform for constructing near-infrared probes with extremely large Stokes shift (>220 nm). Compared with the compound substituted with methylpyridine (PAP), the molecule substituted with methylthiazole orange (PATO) showed better G4 recognition ability, including longer emission (∼720 nm), more significant fluorescent enhancement (∼67-fold), lower background, and excellent photostability. PATO exhibited a sensitive response to mtG4 variation in both somatic cells and human sperms. Most importantly, PATO helped us to discover that mtG4 was significantly increased in cells with mitochondrial respiratory chain damage caused by complex I inhibitors (6-OHDA and rotenone), as well as in human sperms that suffer from oxidative stress. Altogether, our study not only provides a novel ideal molecular platform for constructing high-performance probes but also develops an effective tool for studying the relationship between mtG4 and mitochondrial function in both somatic cells and human sperms.


Assuntos
Corantes Fluorescentes , Purinas , Humanos , Purinas/química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Doenças Mitocondriais/metabolismo , Regulação para Cima , Genoma Mitocondrial , Quadruplex G , Mitocôndrias/metabolismo , Raios Infravermelhos , Células HeLa
15.
Nat Mater ; 22(4): 429-433, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36894771

RESUMO

The lowest-lying fundamental excitation of an incommensurate charge-density-wave material is believed to be a massless phason-a collective modulation of the phase of the charge-density-wave order parameter. However, long-range Coulomb interactions should push the phason energy up to the plasma energy of the charge-density-wave condensate, resulting in a massive phason and fully gapped spectrum1. Using time-domain terahertz emission spectroscopy, we investigate this issue in (TaSe4)2I, a quasi-one-dimensional charge-density-wave insulator. On transient photoexcitation at low temperatures, we find the material strikingly emits coherent, narrowband terahertz radiation. The frequency, polarization and temperature dependences of the emitted radiation imply the existence of a phason that acquires mass by coupling to long-range Coulomb interactions. Our observations underscore the role of long-range interactions in determining the nature of collective excitations in materials with modulated charge or spin order.

16.
Chemistry ; 30(8): e202303519, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38018776

RESUMO

Three unusual ajmaline-macroline type bisindole alkaloids, alsmaphylines A-C, together with their postulated biogenetic precursors, were isolated from the stem barks and leaves of Alstonia macrophylla via the building blocks-based molecular network (BBMN) strategy. Alsmaphyline A represents a rare ajmaline-macroline type bisindole alkaloid with an S-shape polycyclic ring system. Alsmaphylines B and C are two novel ajmaline-macroline type bisindole alkaloids with N-1-C-21' linkages, and the former possesses an unconventional stacked conformation due to the presence of intramolecular noncovalent interactions. The chemical structures including absolute configurations of alsmaphylines A-C were established by comprehensive spectroscopic analyses, electronic circular dichroism (ECD) calculations, and single-crystal X-ray crystallography. In addition, a plausible biosynthetic pathway of these bisindole alkaloids as well as their ability to promote the protein synthesis on HT22 cells were discussed.


Assuntos
Alcaloides , Alstonia , Oxindóis , Alstonia/química , Ajmalina , Alcaloides Indólicos/química , Estrutura Molecular , Alcaloides/química
17.
Mol Pharm ; 21(4): 2012-2024, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38497779

RESUMO

The nonviral delivery systems that combine genes with photosensitizers for multimodal tumor gene/photodynamic therapy (PDT) have attracted much attention. In this study, a series of ROS-sensitive cationic bola-lipids were applied for the gene/photosensitizer codelivery. Zn-DPA was introduced as a cationic headgroup to enhance DNA binding, while the hydrophobic linking chains may facilitate the formation of lipid nanoparticles (LNP) and the encapsulation of photosensitizer Ce6. The length of the hydrophobic chain played an important role in the gene transfection process, and 14-TDZn containing the longest chains showed better DNA condensation, gene transfection, and cellular uptake. 14-TDZn LNPs could well load photosensitizer Ce6 to form 14-TDC without a loss of gene delivery efficiency. 14-TDC was used for codelivery of p53 and Ce6 to achieve enhanced therapeutic effects on the tumor cell proliferation inhibition and apoptosis. Results showed that the codelivery system was more effective in the inhibition of tumor cell proliferation than individual p53 or Ce6 monotherapy. Mechanism studies showed that the production of ROS after Ce6 irradiation could increase the accumulation of p53 protein in tumor cells, thereby promoting caspase-3 activation and inducing apoptosis, indicating some synergistic effect. These results demonstrated that 14-TDC may serve as a promising nanocarrier for gene/PDT combination therapy.


Assuntos
Lipossomos , Nanopartículas , Fotoquimioterapia , Porfirinas , Fármacos Fotossensibilizantes/química , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/genética , Linhagem Celular Tumoral , Nanopartículas/química , DNA , Porfirinas/química
18.
Langmuir ; 40(1): 1007-1015, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38117735

RESUMO

The trade-off that shorter wavelength light facilitates the efficient generation of reactive oxygen species (ROS) from photosensitizer (PS) while facing the drawback of limited penetration depth through skin tissue restricts the further development of photodynamic therapy (PDT). Here, we address this contradiction and achieve visible-light-tailored deep PDT combined with the skin optical clearing technology. With the help of the prepared skin optical clearing gel, the refractive index inhomogeneity between skin tissue components is greatly attenuated, and the light scattering effect within the skin tissue is remarkably reduced. As a consequence, the transmittance of visible light at 600 nm through in vitro porcine skin and in vivo mouse skin after treatment increases from approximately 10 and 40 to 70 and 70%, respectively. Furthermore, in the tumor cell eradication experiment, the local ROS generation efficiency in the experimental group is several times higher than that in the control group owing to improved visible transmittance, which is thus responsible for the complete eradication of tumor cells, even when shaded by skin tissue. The results suggest that this strategy may serve as a valuable supplement to the current deep PDT strategies.


Assuntos
Fotoquimioterapia , Camundongos , Animais , Suínos , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio , Luz , Pele , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico
19.
Biomacromolecules ; 25(1): 366-378, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38064646

RESUMO

The accurate spatial segregation into distinct phases within cell membranes coordinates vital biochemical processes and functionalities in living organisms. One of nature's strategies to localize reactivity is the formation of dynamic raft domains. Most raft models rely on liquid-ordered L0 phases in a liquid-disordered Ld phase lacking correlation and remaining static, often necessitating external agents for phase separation. Here, we introduce a synthetic system of bicomponent glycodendrimersomes coassembled from Janus dendrimers and Janus glycodendrimers (JGDs), where lactose-lactose interactions exclusively drive lateral organization. This mechanism results in modulated phases across two length scales, yielding raft-like microdomains featuring nanoarrays at the nanoscale. By varying the density of lactose and molecular architecture of JGDs, the nanoarray type and size, shape, and spacing of the domains were controlled. Our findings offer insight into the potential primordial origins of rudimentary raft domains and highlight the crucial role of glycans within the glycocalyx.


Assuntos
Células Artificiais , Lactose , Membrana Celular/metabolismo , Polissacarídeos/metabolismo , Microdomínios da Membrana/química , Microdomínios da Membrana/metabolismo
20.
Biomacromolecules ; 25(3): 1541-1549, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38394608

RESUMO

Amphiphilic Janus dendrimers (JDs), synthetic alternatives to lipids, have the potential to expand the scope of nanocarrier delivery systems. JDs self-assemble into vesicles called dendrimersomes, encapsulate both hydrophobic cargo and nucleic acids, and demonstrate enhanced stability in comparison to lipid nanoparticles (LNPs). Here, we report the ability to enhance the cellular uptake of Janus dendrimersomes using DNA aptamers. Azido-modified JDs were synthesized and conjugated to alkyne-modified DNAs using copper-catalyzed azide alkyne cycloaddition. DNA-functionalized JDs form nanometer-sized dendrimersomes in aqueous solution via thin film hydration. These vesicles, now displaying short DNAs, are then hybridized to transferrin receptor binding DNA aptamers. Aptamer-targeted dendrimersomes show improved cellular uptake as compared to control vesicles via fluorescence microscopy and flow cytometry. This work demonstrates the versatility of using click chemistry to conjugate functionalized JDs with biologically relevant molecules and the feasibility of targeting DNA-modified dendrimersomes for drug delivery applications.


Assuntos
Aptâmeros de Nucleotídeos , Dendrímeros , Dendrímeros/química , Sistemas de Liberação de Medicamentos , DNA , Alcinos
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