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1.
Cell ; 182(1): 85-97.e16, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32579975

RESUMO

Small molecule covalent drugs provide desirable therapeutic properties over noncovalent ones for treating challenging diseases. The potential of covalent protein drugs, however, remains unexplored due to protein's inability to bind targets covalently. We report a proximity-enabled reactive therapeutics (PERx) approach to generate covalent protein drugs. Through genetic code expansion, a latent bioreactive amino acid fluorosulfate-L-tyrosine (FSY) was incorporated into human programmed cell death protein-1 (PD-1). Only when PD-1 interacts with PD-L1 did the FSY react with a proximal histidine of PD-L1 selectively, enabling irreversible binding of PD-1 to only PD-L1 in vitro and in vivo. When administrated in immune-humanized mice, the covalent PD-1(FSY) exhibited strikingly more potent antitumor effect over the noncovalent wild-type PD-1, attaining therapeutic efficacy equivalent or superior to anti-PD-L1 antibody. PERx should provide a general platform technology for converting various interacting proteins into covalent binders, achieving specific covalent protein targeting for biological studies and therapeutic capability unattainable with conventional noncovalent protein drugs.


Assuntos
Preparações Farmacêuticas/metabolismo , Proteínas/uso terapêutico , Sequência de Aminoácidos , Animais , Antineoplásicos/metabolismo , Antígeno B7-H1/química , Antígeno B7-H1/metabolismo , Membrana Celular/metabolismo , Proliferação de Células , Células Dendríticas/metabolismo , Humanos , Cinética , Ligantes , Ativação Linfocitária/imunologia , Camundongos , Monócitos/metabolismo , Fenótipo , Proteínas/química , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
2.
J Biol Chem ; 300(4): 107141, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447797

RESUMO

The past 4 decades have witnessed tremendous efforts in deciphering the role of O-GlcNAcylation in a plethora of biological processes. Chemists and biologists have joined hand in hand in the sweet adventure to unravel this unique and universal yet uncharted post-translational modification, and the recent advent of cutting-edge chemical biology and mass spectrometry tools has greatly facilitated the process. Compared with O-GlcNAc, DNA damage response (DDR) is a relatively intensively studied area that could be traced to before the elucidation of the structure of DNA. Unexpectedly, yet somewhat expectedly, O-GlcNAc has been found to regulate various DDR pathways: homologous recombination, nonhomologous end joining, base excision repair, and translesion DNA synthesis. In this review, we first cover the recent structural studies of the O-GlcNAc transferase and O-GlcNAcase, the elegant duo that "writes" and "erases" O-GlcNAc modification. Then we delineate the intricate roles of O-GlcNAc transferase and O-GlcNAcase in DDR. We envision that this is only the beginning of our full appreciation of how O-GlcNAc regulates the blueprint of life-DNA.


Assuntos
N-Acetilglucosaminiltransferases , Animais , Humanos , beta-N-Acetil-Hexosaminidases/metabolismo , beta-N-Acetil-Hexosaminidases/genética , DNA/metabolismo , DNA/química , Dano ao DNA , Reparo do DNA , N-Acetilglucosaminiltransferases/metabolismo , N-Acetilglucosaminiltransferases/genética , Processamento de Proteína Pós-Traducional , Genoma
3.
Circ Res ; 132(4): 483-497, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36795846

RESUMO

Heart disease is a significant burden on global health care systems and is a leading cause of death each year. To improve our understanding of heart disease, high quality disease models are needed. These will facilitate the discovery and development of new treatments for heart disease. Traditionally, researchers have relied on 2D monolayer systems or animal models of heart disease to elucidate pathophysiology and drug responses. Heart-on-a-chip (HOC) technology is an emerging field where cardiomyocytes among other cell types in the heart can be used to generate functional, beating cardiac microtissues that recapitulate many features of the human heart. HOC models are showing great promise as disease modeling platforms and are poised to serve as important tools in the drug development pipeline. By leveraging advances in human pluripotent stem cell-derived cardiomyocyte biology and microfabrication technology, diseased HOCs are highly tuneable and can be generated via different approaches such as: using cells with defined genetic backgrounds (patient-derived cells), adding small molecules, modifying the cells' environment, altering cell ratio/composition of microtissues, among others. HOCs have been used to faithfully model aspects of arrhythmia, fibrosis, infection, cardiomyopathies, and ischemia, to name a few. In this review, we highlight recent advances in disease modeling using HOC systems, describing instances where these models outperformed other models in terms of reproducing disease phenotypes and/or led to drug development.


Assuntos
Cardiomiopatias , Cardiopatias , Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Animais , Humanos , Cardiopatias/terapia , Cardiopatias/metabolismo , Miócitos Cardíacos/metabolismo , Cardiomiopatias/metabolismo , Células-Tronco Pluripotentes/metabolismo , Dispositivos Lab-On-A-Chip
4.
EMBO Rep ; 24(9): e56230, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37489617

RESUMO

Fibrillarin (FBL) is a highly conserved nucleolar methyltransferase responsible for methylation of ribosomal RNA and proteins. Here, we reveal a role for FBL in DNA damage response and its impact on cancer proliferation and sensitivity to DNA-damaging agents. FBL is highly expressed in various cancers and correlates with poor survival outcomes in cancer patients. Knockdown of FBL sensitizes tumor cells and xenografts to DNA crosslinking agents, and leads to homologous recombination-mediated DNA repair defects. We identify Y-box-binding protein-1 (YBX1) as a key interacting partner of FBL, and FBL increases the nuclear accumulation of YBX1 in response to DNA damage. We show that FBL promotes the expression of BRCA1 by increasing the binding of YBX1 to the BRCA1 promoter. Our study sheds light on the regulatory mechanism of FBL in tumorigenesis and DNA damage response, providing potential therapeutic targets to overcome chemoresistance in cancer.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Neoplasias/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Antineoplásicos/uso terapêutico , Dano ao DNA , Linhagem Celular Tumoral , Proteína 1 de Ligação a Y-Box/genética , Proteína 1 de Ligação a Y-Box/metabolismo , Proteína BRCA1/genética
5.
Mol Ther ; 32(5): 1540-1560, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38449312

RESUMO

Podocytes are essential to maintaining the integrity of the glomerular filtration barrier, but they are frequently affected in lupus nephritis (LN). Here, we show that the significant upregulation of Drp1S616 phosphorylation in podocytes promotes mitochondrial fission, leading to mitochondrial dysfunction and podocyte injury in LN. Inhibition or knockdown of Drp1 promotes mitochondrial fusion and protects podocytes from injury induced by LN serum. In vivo, pharmacological inhibition of Drp1 reduces the phosphorylation of Drp1S616 in podocytes in lupus-prone mice. Podocyte injury is reversed when Drp1 is inhibited, resulting in the alleviation of proteinuria. Mechanistically, complement component C5a (C5a) upregulates the phosphorylation of Drp1S616 and promotes mitochondrial fission in podocytes. Moreover, the expression of C5a receptor 1 (C5aR1) is notably upregulated in podocytes in LN. C5a-C5aR1 axis-controlled phosphorylation of Drp1S616 and mitochondrial fission are substantially suppressed when C5aR1 is knocked down by siRNA. Moreover, lupus-prone mice treated with C5aR inhibitor show reduced phosphorylation of Drp1S616 in podocytes, resulting in significantly less podocyte damage. Together, this study uncovers a novel mechanism by which the C5a-C5aR1 axis promotes podocyte injury by enhancing Drp1-mediated mitochondrial fission, which could have significant implications for the treatment of LN.


Assuntos
Complemento C5a , Dinaminas , Nefrite Lúpica , Dinâmica Mitocondrial , Podócitos , Receptor da Anafilatoxina C5a , Podócitos/metabolismo , Podócitos/patologia , Nefrite Lúpica/metabolismo , Nefrite Lúpica/patologia , Nefrite Lúpica/etiologia , Animais , Receptor da Anafilatoxina C5a/metabolismo , Receptor da Anafilatoxina C5a/genética , Camundongos , Dinaminas/metabolismo , Dinaminas/genética , Complemento C5a/metabolismo , Humanos , Fosforilação , Modelos Animais de Doenças , Mitocôndrias/metabolismo , Transdução de Sinais , Feminino
6.
Chromosoma ; 132(4): 257-268, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37227491

RESUMO

Transcriptional repressor B cell lymphoma 6 (Bcl6) is a major transcription factor involved in Tfh cell differentiation and germinal center response, which is regulated by a variety of biological processes. However, the functional impact of post-translational modifications, particularly lysine ß-hydroxybutyrylation (Kbhb), on Bcl6 remains elusive. In this study, we revealed that Bcl6 is modified by Kbhb to affect Tfh cell differentiation, resulting in the decrease of cell population and cytokine IL-21. Furthermore, the modification sites are identified from enzymatic reactions to be lysine residues at positions 376, 377, and 379 by mass spectrometry, which is confirmed by site-directed mutagenesis and functional analyses. Collectively, our present study provides evidence on the Kbhb modification of Bcl6 and also generates new insights into the regulation of Tfh cell differentiation, which is a starting point for a thorough understanding of the functional involvement of Kbhb modification in the differentiations of Tfh and other T cells.


Assuntos
Proteínas de Ligação a DNA , Fatores de Transcrição , Proteínas Proto-Oncogênicas c-bcl-6/genética , Lisina , Linfócitos T Auxiliares-Indutores , Diferenciação Celular
7.
Curr Issues Mol Biol ; 46(4): 3713-3728, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38666961

RESUMO

The aim of this study was to explore the molecular mechanisms through which different levels of GAA affect chicken muscle development by influencing miRNA expression, to lay a theoretical foundation for the identification of key functional small RNAs related to poultry muscle development, and to provide new insights into the regulatory mechanisms of GAA on muscle development and meat quality in broilers. It provides a new theoretical basis for using GAA as a feed additive to improve feed performance. Small RNA sequencing technology was utilized to obtain the expression profiles of miRNA in the broiler pectoral muscle fed with different levels of GAA (0 g/kg, 1.2 g/kg and 3.6 g/kg). An analysis of differentially expressed miRNAs revealed 90 such miRNAs in the three combination comparisons, with gga-miR-130b-5p exhibiting significant differences across all three combinations. Furthermore, three of the differentially expressed miRNAs were performed by RT-qPCR verification, yielding results consistent with those obtained from small RNA sequencing. Target gene prediction, as well as the GO and KEGG enrichment analysis of differentially expressed miRNAs, indicated their involvement in muscle cell differentiation and other processes, particularly those associated with the MAPK signaling pathway. This study has, thus, provided valuable insights and resources for the further exploration of the miRNA molecular mechanism underlying the influence of guanidine acetic acid on broiler muscle development. Combined with previous studies and small RNA sequencing, adding 1.2 g/kg GAA to the diet can better promote the muscle development of broilers.

8.
Anal Chem ; 96(32): 13191-13196, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39074853

RESUMO

Extracellular enzymes are not only strongly correlated with disease development but also play critical roles in modulating immune responses. Therefore, real-time monitoring of extracellular enzymatic activity can afford straightforward insights into their spatiotemporal dynamics upon drug stimulus, and provide promising tools to unravel their key roles in modulating the cell signaling. Although DNA-based sensing probes have been frequently developed for the detection of a variety of biomolecules, there still lacks a modular design strategy for amplified imaging of extracellular enzymatic activity associated with live cells. Herein, we developed an enzymatically triggerable signal amplification strategy for real-time dynamic imaging of extracellular enzyme activity through a cell membrane-confined hybrid chain reaction (HCR). We demonstrated that, by modifying the initiator DNA with enzyme-specific incision sites and cholesterol tail, extracellular enzyme-trigged HCR could be fulfilled on the surface of the cellular membrane, facilitating amplified detection of extracellular enzymatic activity. Dynamic monitoring of enzyme secretion of cancer cells upon stimulus or macrophage cells upon inflammation challenge has also been achieved. We envision that the design strategy could provide valuable information for dissecting the role of extracellular enzymes in modulating cell responses to drug treatment.


Assuntos
Membrana Celular , Humanos , Membrana Celular/metabolismo , Animais , Camundongos , Células RAW 264.7 , DNA/metabolismo , DNA/química , Colesterol/metabolismo , Colesterol/análise , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos
9.
BMC Plant Biol ; 24(1): 622, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38951756

RESUMO

Hybrid genotypes can provide significant yield gains over conventional inbred varieties due to heterosis or hybrid vigor. However, hybrids can also display unintended negative attributes or phenotypes such as extreme pathogen susceptibility. The necrotrophic pathogen Pyrenophora teres f. maculata (Ptm) causes spot form net blotch, which has caused significant yield losses to barley worldwide. Here, we report on a non-transgressive hybrid susceptibility locus in barley identified between the three parental lines CI5791, Tifang and Golden Promise that are resistant to Ptm isolate 13IM.3. However, F2 progeny from CI5791 × Tifang and CI5791 × Golden Promise crosses exhibited extreme susceptibility. The susceptible phenotype segregated in a ratio of 1 resistant:1 susceptible representing a genetic segregation ratio of 1 parental (res):2 heterozygous (sus):1 parental (res) suggesting a single hybrid susceptibility locus. Genetic mapping using a total of 715 CI5791 × Tifang F2 individuals (1430 recombinant gametes) and 149 targeted SNPs delimited the hybrid susceptibility locus designated Susceptibility to Pyrenophora teres 2 (Spt2) to an ~ 198 kb region on chromosome 5H of the Morex V3 reference assembly. This single locus was independently mapped with 83 CI5791 × Golden Promise F2 individuals (166 recombinant gametes) and 180 genome wide SNPs that colocalized to the same Spt2 locus. The CI5791 genome was sequenced using PacBio Continuous Long Read technology and comparative analysis between CI5791 and the publicly available Golden Promise genome assembly determined that the delimited region contained a single high confidence Spt2 candidate gene predicted to encode a pentatricopeptide repeat-containing protein.


Assuntos
Ascomicetos , Mapeamento Cromossômico , Hordeum , Doenças das Plantas , Hordeum/genética , Hordeum/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Ascomicetos/fisiologia , Resistência à Doença/genética , Fenótipo , Polimorfismo de Nucleotídeo Único , Hibridização Genética , Vigor Híbrido/genética , Genótipo
10.
J Transl Med ; 22(1): 215, 2024 02 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424641

RESUMO

BACKGROUND: Cardiovascular diseases (CVDs) are the leading cause of death around the world. Most CVDs-related death can be prevented by the optimal management of risk factors such as unhealthy diet and physical inactivity. Clinical practice guidelines (CPGs) for CVDs, provide some evidence-based recommendations which help healthcare professionals to achieve the best care for patients with CVDs. This systematic review aims to appraise the methodological quality of CPGs systematically and summarize the recommendations of self-managed non-pharmacological interventions for the prevention and management of CVDs provided by the selected guidelines. METHODS: A comprehensive electronic literature search was conducted via six databases (PubMed, Medline, The Cochrane Library, Embase, CINAHL, and Web of Science), seven professional heart association websites, and nine guideline repositories. The Appraisal of Guidelines, Research and Evaluation II (AGREE II) instrument was adopted to critically appraise the methodological quality of the selected guidelines. Content analysis was used to summarise recommended self-managed non-pharmacological interventions for CVDs. RESULTS: Twenty-three CPGs regarding different CVDs were included, in which four guidelines of CVDs, three for coronary heart diseases, seven for heart failure, two for atrial fibrillation, three for stroke, three for peripheral arterial disease, and one for hypertrophic cardiomyopathy. Twenty CPGs were appraised as high quality, and three CPGs as moderate quality. All twenty-three CPGs were recommended for use with or without modification. The domain of "Editorial Independence" had the highest standardized percentage (93.47%), whereas the domain of "Applicability" had the lowest mean domain score of 75.41%. The content analysis findings summarised some common self-managed non-pharmacological interventions, which include healthy diet, physical activity, smoking cessation, alcohol control, and weight management. Healthy diet and physical acidity are the most common and agreed on self-managed interventions for patients with CVDs. There are some inconsistencies identified in the details of recommended interventions, the intervention itself, the grade of recommendation, and the supported level of evidence. CONCLUSION: The majority of the summarized non-pharmacological interventions were strongly recommended with moderate to high-quality levels of evidence. Healthcare professionals and researchers can adopt the results of this review to design self-managed non-pharmacological interventions for patients with CVDs.


Assuntos
Doenças Cardiovasculares , Insuficiência Cardíaca , Doença Arterial Periférica , Autogestão , Humanos , Doenças Cardiovasculares/terapia , Guias de Prática Clínica como Assunto
11.
Acc Chem Res ; 56(12): 1482-1493, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37262339

RESUMO

With unparalleled programmability, DNA has evolved as a powerful scaffold for engineering intricate and dynamic systems that can perform diverse tasks. By allowing serial detection of molecular targets in complex cellular milieus, increasingly sophisticated DNA sensors have not only promoted significant advances in unveiling the fundamental mechanisms of various pathophysiological processes but also provided a useful toolkit for disease diagnostics based on molecular signatures. Despite much progress, an inherent limitation of DNA-based sensors is that they often lack spatial control and cell-type selectivity for the sensing activity because of their "always active" design mechanism. Since most molecular targets of interests are not exclusive to disease cells, they are also shared by normal cells, the application of such biosensors for disease-specific imaging is limited by inadequate signal-to-background ratios due to indistinguishable signal response in both disease and normal cells. Therefore, imparting biosensors with spatial controllability remains a key issue to achieve molecular imaging with high sensitivity and cell specificity.As a biocatalyst, enzyme has been found to be closely related with the pathological conditions of numerous diseases. For example, many nucleases, protease, and kinases have been identified overexpressed in disease cells and considered as important biomarkers of cancer, inflammation, and neurological diseases. Recently, we have envisioned that such pathophysiology-associated enzymes could be leveraged as endogenous triggers to achieve spatial control over the molecular imaging activity of the DNA-based sensors with improved cell-specificity. In this Account, we outline the research efforts from our group on the development of endogenous enzyme-triggered, DNA-based sensor technology that enables spatially controlled, cell-type selective molecular imaging. With programmable DNA design and further engineering of enzymatically cleavable sites, a series of DNAzyme- and aptamer-based sensors have been developed for enzyme-controlled imaging of various molecular targets (e.g., metal ions and small molecules) in a cancer cell-selective manner. In particular, by introduction of PNA as bridge molecules to engineer DNA-based sensors with functional peptides, the conceptual design of protease-activated DNA biosensors has been established for spatioselective molecular imaging in cancer cells and extracellular tumor microenvironments. Furthermore, enzyme-triggered signal amplification approaches, such as enzymatically activated molecular beacon and catalytic hairpin assembly, have been developed for spatially selective RNA imaging in specific disease cells (e.g., inflammatory cells and cancer cells), which enables enhanced disease-site specificity and thus improved signal-to-background ratio. The signal amplification strategy is further expanded to cell-selective amplified imaging of non-RNA species through the combination with functional DNA design. Finally, the challenges and potential future directions in this burgeoning field are discussed. We hope this Account offers insights into rational design of enzymatically controlled, DNA-based sensor platforms for opening new frontiers in spatially resolved, cell-selective molecular imaging. We believe that the continuing advances in DNA-based molecular sensing technology together with the discoveries of diverse disease-associated enzymes will promise to usher a new era of diagnosis.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , DNA/química , DNA Catalítico/química , Imagem Molecular , Tecnologia , Peptídeo Hidrolases , Técnicas Biossensoriais/métodos
12.
Microb Pathog ; 188: 106562, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307370

RESUMO

Bacterial outer membrane vesicles (OMVs) can package and deliver virulence factors into host cells, which is an important mechanism mediating host-pathogen interactions. It has been reported that small RNAs (sRNAs) can be packed into OMVs with varying relative abundance, which might affect the function and/or stability of host mRNAs. In this study, we used OptiPrep density gradient ultra-high-speed centrifugation to purify OMVs from Pseudomonas aeruginosa. Next, the sequences and abundance of sRNAs were detected by using Small RNA-Seq. In particular, sRNA4518698, sRNA2316613 and sRNA809738 were the three most abundant sRNAs in OMVs, which are all fragments of P. aeruginosa non-coding RNAs. sRNAs were shielded within the interior of OMVs and remained resistant to external RNase cleavage. The miRanda and RNAhybrid analysis demonstrated that those sRNAs could target a large number of host mRNAs, which were enriched in host immune responses by the functions of GO and KEGG enrichment. Experimentally, we demonstrated that the transfection of synthetic sRNA4518698, sRNA2316613, or sRNA809738 could reduce the expression of innate immune response genes in RAW264.7 cells. Together, we demonstrated that P. aeruginosa OMVs sRNAs can regulate innate immune responses. This study uncovered a mechanism in which the OMVs regulate host responses by transferring bacterial sRNAs.


Assuntos
Infecções por Pseudomonas , Pseudomonas aeruginosa , Humanos , Pseudomonas aeruginosa/fisiologia , Infecções por Pseudomonas/microbiologia , Imunidade Inata , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , Interações Hospedeiro-Patógeno , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
13.
Physiol Plant ; 176(1): e14206, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38356346

RESUMO

Aroma or fragrance in rice is a genetically controlled trait; Its high appreciation by consumers increases the rice market price. Previous studies have revealed that the rice aroma is controlled by a specific gene called BETAINE ALDEHYDE DEHYDROGENASE (OsBADH2), and mutation of this gene leads to the accumulation of an aromatic substance 2-acetyl-1-pyrroline (2-AP). The use of genetic engineering to produce aroma in commercial and cultivated hybrids is a contemporary need for molecular breeding. The current study reports the generation of aroma in the three-line hybrid restorer line Shu-Hui-313 (SH313). We created knock-out (KO) lines of OsBADH2 through the CRISPR/Cas9. The analysis of KO lines revealed a significantly increased content of 2AP in the grains compared with the control. However, other phenotypic traits (plant height, seed setting rate, and 1000-grain weight) were significantly decreased. These KO lines were crossed with a non-aromatic three-line hybrid rice male sterile line (Rong-7-A) to produce Rong-7-You-626 (R7Y626), R7Y627 and R7Y628. The measurement of 2-AP revealed significantly increased contents in these cross combinations. We compared the content of 2-AP in tissues at the booting stage. Data revealed that young spike stalk base contained the highest content of 2-AP and can be used for identification (by simple chewing) of aromatic lines under field conditions. In conclusion, our dataset offers a genetic source and illustrates the generation of aroma in non-aromatic hybrids, and outlines a straightforward identification under field conditions.


Assuntos
Betaína/análogos & derivados , Oryza , Oryza/genética , Sistemas CRISPR-Cas/genética , Odorantes , Genes de Plantas
14.
Inorg Chem ; 63(29): 13392-13401, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38991459

RESUMO

Fused porphyrinoids have received increasing interest in light of their extended conjugation and unique coordination behavior. On the basis of our previously reported multiply fused pentaphyrin isomers 1 and 2, a novel isomer 3 has been synthesized in this work. 3 possesses a hexacyclic fused moiety with a nearly coplanar CCNN cavity involving an inverted pyrrole, which is slightly different from the CNNN ones of 1 and 2 involving an N-confused pyrrole. 1-3 possess cavities with three depronatable protons and thus they all can generate Cu(III) complexes. However, only 3Cu is stable under ambient conditions. On the other hand, 3 remains intact upon treatment with Pd(II) ions, while 1 and 2 could undergo structural rearrangement to accommodate Pd(II), affording 1Pd and 2Pd accompanied by the formation of a lactone ring and the addition of a methoxy group, respectively. Compared with the free bases, the complexes show distinct aromaticity and more intense near-infrared (NIR) absorption up to ca. 1600, 1170, and 1500 nm, respectively. The results indicate that the subtle modification of the linking modes between the pyrrolic units in the fused pentaphyrinoids is effective in modulating the coordination behavior for synthesizing complexes with tunable aromaticity and NIR absorption.

15.
Org Biomol Chem ; 22(30): 6090-6094, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39005158

RESUMO

The first amidation of carbazoles at the N9 position via palladium-catalyzed hydroamination of isocyanates is demonstrated. This simple, general and efficient method could deliver a wide range of carbazole-N-carboxamides in up to 99% yield. The salient features of this transformation include simple conditions with no need for a strong base, high chemo- and regio-selectivities and good functional group tolerance. In particular, this work-up-free and chromatography-free protocol is time-saving, cost-effective and user-friendly.

16.
J Pathol ; 260(4): 376-389, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37230111

RESUMO

The suggestion that the systemic immune response in lymph nodes (LNs) conveys prognostic value for triple-negative breast cancer (TNBC) patients has not previously been investigated in large cohorts. We used a deep learning (DL) framework to quantify morphological features in haematoxylin and eosin-stained LNs on digitised whole slide images. From 345 breast cancer patients, 5,228 axillary LNs, cancer-free and involved, were assessed. Generalisable multiscale DL frameworks were developed to capture and quantify germinal centres (GCs) and sinuses. Cox regression proportional hazard models tested the association between smuLymphNet-captured GC and sinus quantifications and distant metastasis-free survival (DMFS). smuLymphNet achieved a Dice coefficient of 0.86 and 0.74 for capturing GCs and sinuses, respectively, and was comparable to an interpathologist Dice coefficient of 0.66 (GC) and 0.60 (sinus). smuLymphNet-captured sinuses were increased in LNs harbouring GCs (p < 0.001). smuLymphNet-captured GCs retained clinical relevance in LN-positive TNBC patients whose cancer-free LNs had on average ≥2 GCs, had longer DMFS (hazard ratio [HR] = 0.28, p = 0.02) and extended GCs' prognostic value to LN-negative TNBC patients (HR = 0.14, p = 0.002). Enlarged smuLymphNet-captured sinuses in involved LNs were associated with superior DMFS in LN-positive TNBC patients in a cohort from Guy's Hospital (multivariate HR = 0.39, p = 0.039) and with distant recurrence-free survival in 95 LN-positive TNBC patients of the Dutch-N4plus trial (HR = 0.44, p = 0.024). Heuristic scoring of subcapsular sinuses in LNs of LN-positive Tianjin TNBC patients (n = 85) cross-validated the association of enlarged sinuses with shorter DMFS (involved LNs: HR = 0.33, p = 0.029 and cancer-free LNs: HR = 0.21 p = 0.01). Morphological LN features reflective of cancer-associated responses are robustly quantifiable by smuLymphNet. Our findings further strengthen the value of assessment of LN properties beyond the detection of metastatic deposits for prognostication of TNBC patients. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Aprendizado Profundo , Neoplasias de Mama Triplo Negativas , Humanos , Linfonodos/patologia , Metástase Linfática/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Neoplasias de Mama Triplo Negativas/terapia , Neoplasias de Mama Triplo Negativas/patologia , Feminino , Ensaios Clínicos como Assunto
17.
Bioorg Chem ; 147: 107319, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38593529

RESUMO

Reactivating p53 activity to restore its anticancer function is an attractive cancer treatment strategy. In this study, we designed and synthesized a series of novel PROTACs to reactivate p53 via the co-degradation of CK1α and CDK7/9 proteins. Bioactivity studies showed that the selected PROTAC 13i exhibited potency antiproliferative activity in MV4-11 (IC50 = 0.096 ± 0.012 µM) and MOLM-13 (IC50 = 0.072 ± 0.014 µM) cells, and induced apoptosis of MV4-11 cells. Western-blot analysis showed that PROTAC 13i triple CK1α and CDK7/9 protein degradation resulted in the significantly increased expression of p53. At the same time, the transcriptional repression due to the degradation significantly reduced downstream gene expression of MYC, MDM2, BCL-2 and MCL-1, and reduced the inflammatory cytokine levels of TNF-α, IL-1ß and IL-6 in PMBCs. These results indicate the beneficial impact of simultaneous CK1α and CDK7/9 degradation for acute myeloid leukemia therapy.


Assuntos
Antineoplásicos , Caseína Quinase Ialfa , Proliferação de Células , Quinase 9 Dependente de Ciclina , Quinases Ciclina-Dependentes , Ensaios de Seleção de Medicamentos Antitumorais , Leucemia Mieloide Aguda , Proteína Supressora de Tumor p53 , Humanos , Proteína Supressora de Tumor p53/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Caseína Quinase Ialfa/metabolismo , Caseína Quinase Ialfa/antagonistas & inibidores , Proliferação de Células/efeitos dos fármacos , Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Quinase 9 Dependente de Ciclina/metabolismo , Relação Estrutura-Atividade , Estrutura Molecular , Quinases Ciclina-Dependentes/antagonistas & inibidores , Quinases Ciclina-Dependentes/metabolismo , Relação Dose-Resposta a Droga , Apoptose/efeitos dos fármacos , Descoberta de Drogas , Linhagem Celular Tumoral , Proteólise/efeitos dos fármacos , Células Tumorais Cultivadas , Quimera de Direcionamento de Proteólise , Quinase Ativadora de Quinase Dependente de Ciclina
18.
Environ Res ; 242: 117754, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38016497

RESUMO

Submerged macrophytes play important roles in nutrient cycling and are widely used in ecological restoration to alleviate eutrophication and improve water quality in lakes. Epiphytic microbial communities on leaves of submerged macrophytes might promote nitrogen cycling, but the mechanisms and quantification of their contributions remain unclear. Here, four types of field zones with different nutrient levels and submerged macrophytes, eutrophic + Vallisneria natans (EV), eutrophic + V. natans + Hydrilla verticillata, mesotrophic + V. natans + H. verticillata, and eutrophic without macrophytes were selected to investigate the microbial communities that involved in nitrification and denitrification. The alpha diversity of bacterial community was higher in the phyllosphere than in the water, and that of H. verticillata was higher compared to V. natans. Bacterial community structures differed significantly between the four zones. The highest relative abundance of dominant bacterioplankton genera involved in nitrification and denitrification was observed in the EV zone. Similarly, the alpha diversity of the epiphytic ammonia-oxidizing archaea and nosZI-type denitrifiers were highest in the EV zone. Consist with the diversity patterns, the potential denitrification rates were higher in the phyllosphere than those in the water. Higher potential denitrification rates in the phyllosphere were also found in H. verticillata than those in V. natans. Anammox was not detected in all samples. Nutrient loads, especially nitrogen concentrations were important factors influencing potential nitrification, denitrification rates, and bacterial communities, especially for the epiphytic nosZI-type taxa. Overall, we observed that the phyllosphere harbors more microbes and promotes higher denitrification rates compared to water, and epiphytic bacterial communities are shaped by nitrogen nutrients and macrophyte species, indicating that epiphytic microorganisms of submerged macrophytes can effectively contribute to the N removal in shallow lakes.


Assuntos
Desnitrificação , Hydrocharitaceae , Nitrogênio , Nitrificação , Bactérias/genética , Organismos Aquáticos , Lagos/microbiologia
19.
Nutr Metab Cardiovasc Dis ; 34(7): 1631-1638, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38653673

RESUMO

BACKGROUND AND AIMS: It has been reported that maresin 1 (MaR1) is able to protect against the development of atherogenesis in cellular and animal models. This study was performed to investigate whether plasma MaR1 is associated with the risk of atherosclerotic cardiovascular disease (ASCVD) at the population level. METHODS AND RESULTS: The study included 2822 non-ASCVD participants from a community-based cohort who were followed for about 8 years. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) for ASCVD events according to baseline MaR1 quartiles were calculated using the Cox proportional hazards model. During follow-up, a total of 290 new ASCVD cases were identified. The restricted cubic spline analysis indicated a linear dose-response association between plasma MaR1 and incident ASCVD. In addition, the adjusted-HR (95% CI) for ASCVD events associated with one standard deviation increase in MaR1 was 0.79 (0.68-0.91). Moreover, the adjusted-HRs (95% CIs) for ASCVD events associated with the second, third and fourth quartiles versus the first quartile of plasma MaR1 were 1.00, 1.04 (0.76, 1.42), 0.88 (0.64, 1.22) and 0.58 (0.41, 0.84), respectively. Mediation analyses showed that the association between MaR1 and incident ASCVD was partially mediated by small dense low-density lipoprotein cholesterol, with a mediation proportion of 9.23%. Further, the net reclassification improvement and integrated discrimination improvement of ASCVD risk were significantly improved when MaR1 was added to basic model established by conventional risk factors (all p < 0.01). CONCLUSIONS: Elevated plasma MaR1 concentrations are associated with a lower risk of ASCVD development.


Assuntos
Aterosclerose , Biomarcadores , Ácidos Docosa-Hexaenoicos , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Aterosclerose/epidemiologia , Aterosclerose/sangue , Aterosclerose/diagnóstico , Medição de Risco , Incidência , China/epidemiologia , Biomarcadores/sangue , Idoso , Fatores de Tempo , Ácidos Docosa-Hexaenoicos/sangue , Adulto , Prognóstico , Estudos Prospectivos , Fatores de Risco , Fatores de Proteção , População do Leste Asiático
20.
Mol Ther ; 31(1): 193-210, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36146932

RESUMO

Interferon γ (IFNγ) produced by T cells represents the featured cytokine and is central to the pathogenesis of lupus nephritis (LN). Here, we identified nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in the salvage NAD+ biosynthetic pathway, as playing a key role in controlling IFNγ production by CD4+ T cells in LN. Our data revealed that CD4+ T cells from LN showed an enhanced NAMPT-mediated NAD+ biosynthetic process, which was positively correlated with IFNγ production in CD4+ T cells. NAMPT promoted aerobic glycolysis and mitochondrial respiration in CD4+ T cells from patients with LN or MRL/lpr mice through the production of NAD+. By orchestrating metabolic fitness, NAMPT promoted translational efficiency of Ifng in CD4+ T cells. In vivo, knockdown of NAMPT by small interfering RNA (siRNA) or pharmacological inhibition of NAMPT by FK866 suppressed IFNγ production in CD4+ T cells, leading to reduced inflammatory infiltrates and ameliorated kidney damage in lupus mice. Taken together, this study uncovers a metabolic checkpoint of IFNγ-producing CD4+ T cells in LN in which therapeutically targeting NAMPT has the potential to normalize metabolic competence and blunt pathogenicity of CD4+ T cells in LN.


Assuntos
Interferon gama , Nefrite Lúpica , Camundongos , Animais , Interferon gama/genética , Linfócitos T/metabolismo , Nicotinamida Fosforribosiltransferase/genética , Nicotinamida Fosforribosiltransferase/metabolismo , NAD/metabolismo , Camundongos Endogâmicos MRL lpr , Citocinas/metabolismo , RNA Interferente Pequeno , Linfócitos T CD4-Positivos/metabolismo
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