Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.111
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Annu Rev Immunol ; 39: 583-609, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33637019

RESUMO

Understanding tumor immune microenvironments is critical for identifying immune modifiers of cancer progression and developing cancer immunotherapies. Recent applications of single-cell RNA sequencing (scRNA-seq) in dissecting tumor microenvironments have brought important insights into the biology of tumor-infiltrating immune cells, including their heterogeneity, dynamics, and potential roles in both disease progression and response to immune checkpoint inhibitors and other immunotherapies. This review focuses on the advances in knowledge of tumor immune microenvironments acquired from scRNA-seq studies across multiple types of human tumors, with a particular emphasis on the study of phenotypic plasticity and lineage dynamics of immune cells in the tumor environment. We also discuss several imminent questions emerging from scRNA-seq observations and their potential solutions on the horizon.


Assuntos
Neoplasias , Análise de Célula Única , Animais , Humanos , Imunoterapia , Neoplasias/terapia , Análise de Sequência de RNA , Microambiente Tumoral
2.
Cell ; 187(2): 294-311.e21, 2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38128537

RESUMO

Lactylation is a lactate-induced post-translational modification best known for its roles in epigenetic regulation. Herein, we demonstrate that MRE11, a crucial homologous recombination (HR) protein, is lactylated at K673 by the CBP acetyltransferase in response to DNA damage and dependent on ATM phosphorylation of the latter. MRE11 lactylation promotes its binding to DNA, facilitating DNA end resection and HR. Inhibition of CBP or LDH downregulated MRE11 lactylation, impaired HR, and enhanced chemosensitivity of tumor cells in patient-derived xenograft and organoid models. A cell-penetrating peptide that specifically blocks MRE11 lactylation inhibited HR and sensitized cancer cells to cisplatin and PARPi. These findings unveil lactylation as a key regulator of HR, providing fresh insights into the ways in which cellular metabolism is linked to DSB repair. They also imply that the Warburg effect can confer chemoresistance through enhancing HR and suggest a potential therapeutic strategy of targeting MRE11 lactylation to mitigate the effects.


Assuntos
Proteínas de Ligação a DNA , Proteína Homóloga a MRE11 , Reparo de DNA por Recombinação , Humanos , DNA , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Epigênese Genética , Recombinação Homóloga , Proteína Homóloga a MRE11/metabolismo , Ácido Láctico/metabolismo
3.
Cell ; 185(6): 980-994.e15, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35303428

RESUMO

The emergence of hypervirulent clade 2 Clostridioides difficile is associated with severe symptoms and accounts for >20% of global infections. TcdB is a dominant virulence factor of C. difficile, and clade 2 strains exclusively express two TcdB variants (TcdB2 and TcdB4) that use unknown receptors distinct from the classic TcdB. Here, we performed CRISPR/Cas9 screens for TcdB4 and identified tissue factor pathway inhibitor (TFPI) as its receptor. Using cryo-EM, we determined a complex structure of the full-length TcdB4 with TFPI, defining a common receptor-binding region for TcdB. Residue variations within this region divide major TcdB variants into 2 classes: one recognizes Frizzled (FZD), and the other recognizes TFPI. TFPI is highly expressed in the intestinal glands, and recombinant TFPI protects the colonic epithelium from TcdB2/4. These findings establish TFPI as a colonic crypt receptor for TcdB from clade 2 C. difficile and reveal new mechanisms for CDI pathogenesis.


Assuntos
Toxinas Bacterianas , Clostridioides difficile , Proteínas de Bactérias/química , Toxinas Bacterianas/química , Clostridioides difficile/genética , Lipoproteínas/genética
4.
Cell ; 169(7): 1342-1356.e16, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28622514

RESUMO

Systematic interrogation of tumor-infiltrating lymphocytes is key to the development of immunotherapies and the prediction of their clinical responses in cancers. Here, we perform deep single-cell RNA sequencing on 5,063 single T cells isolated from peripheral blood, tumor, and adjacent normal tissues from six hepatocellular carcinoma patients. The transcriptional profiles of these individual cells, coupled with assembled T cell receptor (TCR) sequences, enable us to identify 11 T cell subsets based on their molecular and functional properties and delineate their developmental trajectory. Specific subsets such as exhausted CD8+ T cells and Tregs are preferentially enriched and potentially clonally expanded in hepatocellular carcinoma (HCC), and we identified signature genes for each subset. One of the genes, layilin, is upregulated on activated CD8+ T cells and Tregs and represses the CD8+ T cell functions in vitro. This compendium of transcriptome data provides valuable insights and a rich resource for understanding the immune landscape in cancers.


Assuntos
Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Análise de Sequência de RNA , Análise de Célula Única , Subpopulações de Linfócitos T/imunologia , Linfócitos T CD8-Positivos/imunologia , Humanos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos T Reguladores/imunologia , Microambiente Tumoral
5.
Nature ; 630(8015): 222-229, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38657677

RESUMO

Gamma delta (γδ) T cells, a unique T cell subgroup, are crucial in various immune responses and immunopathology1-3. The γδ T cell receptor (TCR), which is generated by γδ T cells, recognizes a diverse range of antigens independently of the major histocompatibility complex2. The γδ TCR associates with CD3 subunits, initiating T cell activation and holding great potential in immunotherapy4. Here we report the structures of two prototypical human Vγ9Vδ2 and Vγ5Vδ1 TCR-CD3 complexes5,6, revealing two distinct assembly mechanisms that depend on Vγ usage. The Vγ9Vδ2 TCR-CD3 complex is monomeric, with considerable conformational flexibility in the TCRγ-TCRδ extracellular domain and connecting peptides. The length of the connecting peptides regulates the ligand association and T cell activation. A cholesterol-like molecule wedges into the transmembrane region, exerting an inhibitory role in TCR signalling. The Vγ5Vδ1 TCR-CD3 complex displays a dimeric architecture, whereby two protomers nestle back to back through the Vγ5 domains of the TCR extracellular domains. Our biochemical and biophysical assays further corroborate the dimeric structure. Importantly, the dimeric form of the Vγ5Vδ1 TCR is essential for T cell activation. These findings reveal organizing principles of the γδ TCR-CD3 complex, providing insights into the unique properties of γδ TCR and facilitating immunotherapeutic interventions.


Assuntos
Complexo CD3 , Receptores de Antígenos de Linfócitos T gama-delta , Linfócitos T , Humanos , Complexo CD3/química , Complexo CD3/imunologia , Complexo CD3/metabolismo , Complexo CD3/ultraestrutura , Colesterol/metabolismo , Colesterol/química , Microscopia Crioeletrônica , Ligantes , Ativação Linfocitária/imunologia , Modelos Moleculares , Domínios Proteicos , Multimerização Proteica , Receptores de Antígenos de Linfócitos T gama-delta/química , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/ultraestrutura , Linfócitos T/química , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transdução de Sinais , Membrana Celular/química , Membrana Celular/metabolismo
6.
EMBO J ; 43(12): 2486-2505, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38698215

RESUMO

The Casparian strip is a barrier in the endodermal cell walls of plants that allows the selective uptake of nutrients and water. In the model plant Arabidopsis thaliana, its development and establishment are under the control of a receptor-ligand mechanism termed the Schengen pathway. This pathway facilitates barrier formation and activates downstream compensatory responses in case of dysfunction. However, due to a very tight functional association with the Casparian strip, other potential signaling functions of the Schengen pathway remain obscure. In this work, we created a MYB36-dependent synthetic positive feedback loop that drives Casparian strip formation independently of Schengen-induced signaling. We evaluated this by subjecting plants in which the Schengen pathway has been uncoupled from barrier formation, as well as a number of established barrier-mutant plants, to agar-based and soil conditions that mimic agricultural settings. Under the latter conditions, the Schengen pathway is necessary for the establishment of nitrogen-deficiency responses in shoots. These data highlight Schengen signaling as an essential hub for the adaptive integration of signaling from the rhizosphere to aboveground tissues.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Nitrogênio , Brotos de Planta , Transdução de Sinais , Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Nitrogênio/metabolismo , Brotos de Planta/metabolismo , Brotos de Planta/crescimento & desenvolvimento , Solo/química , Regulação da Expressão Gênica de Plantas , Proteínas Quinases/metabolismo , Proteínas Quinases/genética , Parede Celular/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
7.
EMBO J ; 42(6): e112094, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36727301

RESUMO

DNA-PKcs is a key regulator of DNA double-strand break repair. Apart from its canonical role in the DNA damage response, DNA-PKcs is involved in the cellular response to oxidative stress (OS), but its exact role remains unclear. Here, we report that DNA-PKcs-deficient human cells display depolarized mitochondria membrane potential (MMP) and reoriented metabolism, supporting a role for DNA-PKcs in oxidative phosphorylation (OXPHOS). DNA-PKcs directly interacts with mitochondria proteins ANT2 and VDAC2, and formation of the DNA-PKcs/ANT2/VDAC2 (DAV) complex supports optimal exchange of ADP and ATP across mitochondrial membranes to energize the cell via OXPHOS and to maintain MMP. Moreover, we demonstrate that the DAV complex temporarily dissociates in response to oxidative stress to attenuate ADP-ATP exchange, a rate-limiting step for OXPHOS. Finally, we found that dissociation of the DAV complex is mediated by phosphorylation of DNA-PKcs at its Thr2609 cluster by ATM kinase. Based on these findings, we propose that the coordination between the DAV complex and ATM serves as a novel oxidative stress checkpoint to decrease ROS production from mitochondrial OXPHOS and to hasten cellular recovery from OS.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ligação a DNA , Estresse Oxidativo , Humanos , Trifosfato de Adenosina/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , DNA/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Mitocôndrias/metabolismo , Fosforilação
8.
Brief Bioinform ; 24(5)2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37482409

RESUMO

Numerous biological studies have shown that considering disease-associated micro RNAs (miRNAs) as potential biomarkers or therapeutic targets offers new avenues for the diagnosis of complex diseases. Computational methods have gradually been introduced to reveal disease-related miRNAs. Considering that previous models have not fused sufficiently diverse similarities, that their inappropriate fusion methods may lead to poor quality of the comprehensive similarity network and that their results are often limited by insufficiently known associations, we propose a computational model called Generative Adversarial Matrix Completion Network based on Multi-source Data Fusion (GAMCNMDF) for miRNA-disease association prediction. We create a diverse network connecting miRNAs and diseases, which is then represented using a matrix. The main task of GAMCNMDF is to complete the matrix and obtain the predicted results. The main innovations of GAMCNMDF are reflected in two aspects: GAMCNMDF integrates diverse data sources and employs a nonlinear fusion approach to update the similarity networks of miRNAs and diseases. Also, some additional information is provided to GAMCNMDF in the form of a 'hint' so that GAMCNMDF can work successfully even when complete data are not available. Compared with other methods, the outcomes of 10-fold cross-validation on two distinct databases validate the superior performance of GAMCNMDF with statistically significant results. It is worth mentioning that we apply GAMCNMDF in the identification of underlying small molecule-related miRNAs, yielding outstanding performance results in this specific domain. In addition, two case studies about two important neoplasms show that GAMCNMDF is a promising prediction method.


Assuntos
MicroRNAs , Neoplasias , Humanos , MicroRNAs/genética , Algoritmos , Biologia Computacional/métodos , Neoplasias/genética , Bases de Dados Genéticas , Predisposição Genética para Doença
9.
Brief Bioinform ; 24(4)2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37366591

RESUMO

MicroRNAs (miRNAs) have significant implications in diverse human diseases and have proven to be effectively targeted by small molecules (SMs) for therapeutic interventions. However, current SM-miRNA association prediction models do not adequately capture SM/miRNA similarity. Matrix completion is an effective method for association prediction, but existing models use nuclear norm instead of rank function, which has some drawbacks. Therefore, we proposed a new approach for predicting SM-miRNA associations by utilizing the truncated schatten p-norm (TSPN). First, the SM/miRNA similarity was preprocessed by incorporating the Gaussian interaction profile kernel similarity method. This identified more SM/miRNA similarities and significantly improved the SM-miRNA prediction accuracy. Next, we constructed a heterogeneous SM-miRNA network by combining biological information from three matrices and represented the network with its adjacency matrix. Finally, we constructed the prediction model by minimizing the truncated schatten p-norm of this adjacency matrix and we developed an efficient iterative algorithmic framework to solve the model. In this framework, we also used a weighted singular value shrinkage algorithm to avoid the problem of excessive singular value shrinkage. The truncated schatten p-norm approximates the rank function more closely than the nuclear norm, so the predictions are more accurate. We performed four different cross-validation experiments on two separate datasets, and TSPN outperformed various most advanced methods. In addition, public literature confirms a large number of predictive associations of TSPN in four case studies. Therefore, TSPN is a reliable model for SM-miRNA association prediction.


Assuntos
MicroRNAs , Humanos , MicroRNAs/genética , Algoritmos , Biologia Computacional/métodos
10.
FASEB J ; 38(7): e23587, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38568835

RESUMO

Mastitis is a disease characterized by congestion, swelling, and inflammation of the mammary gland and usually caused by infection with pathogenic microorganisms. Furthermore, the development of mastitis is closely linked to the exogenous pathway of the gastrointestinal tract. However, the regulatory mechanisms governing the gut-metabolism-mammary axis remain incompletely understood. The present study revealed alterations in the gut microbiota of mastitis rats characterized by an increased abundance of the Proteobacteria phylum. Plasma analysis revealed significantly higher levels of L-isoleucine and cholic acid along with 7-ketodeoxycholic acid. Mammary tissue showed elevated levels of arachidonic acid metabolites and norlithocholic acid. Proteomic analysis showed increased levels of IFIH1, Tnfaip8l2, IRGM, and IRF5 in mastitis rats, which suggests that mastitis triggers an inflammatory response and immune stress. Follistatin (Fst) and progesterone receptor (Pgr) were significantly downregulated, raising the risk of breast cancer. Extracellular matrix (ECM) receptors and focal adhesion signaling pathways were downregulated, while blood-milk barrier integrity was disrupted. Analysis of protein-metabolic network regulation revealed that necroptosis, protein digestion and absorption, and arachidonic acid metabolism were the principal regulatory pathways involved in the development of mastitis. In short, the onset of mastitis leads to changes in the microbiota and alterations in the metabolic profiles of various biological samples, including colonic contents, plasma, and mammary tissue. Key manifestations include disturbances in bile acid metabolism, amino acid metabolism, and arachidonic acid metabolism. At the same time, the integrity of the blood-milk barrier is compromised while inflammation is promoted, thereby reducing cell adhesion in the mammary glands. These findings contribute to a more comprehensive understanding of the metabolic status of mastitis and provide new insights into its impact on the immune system.


Assuntos
Mastite , Infecções Estafilocócicas , Feminino , Humanos , Ratos , Animais , Staphylococcus aureus/fisiologia , Proteômica , Ácido Araquidônico/metabolismo , Mastite/microbiologia , Mastite/patologia , Mastite/veterinária , Inflamação/metabolismo , Redes e Vias Metabólicas , Glândulas Mamárias Animais/metabolismo , Infecções Estafilocócicas/metabolismo
11.
EMBO Rep ; 24(9): e56981, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37535645

RESUMO

Adolescent cocaine abuse increases the risk for developing addiction in later life, but the underlying molecular mechanism remains poorly understood. Here, we establish adolescent cocaine-exposed (ACE) male mouse models. A subthreshold dose of cocaine (sdC) treatment, insufficient to produce conditioned place preference (CPP) in adolescent mice, induces CPP in ACE mice during adulthood, along with more activated CaMKII-positive neurons, higher dual specificity protein kinase phosphatase-1 (Dusp1) mRNA, lower DUSP1 activity, and lower DUSP1 expression in CaMKII-positive neurons in the medial prefrontal cortex (mPFC). Overexpressing DUSP1 in CaMKII-positive neurons suppresses neuron activity and blocks sdC-induced CPP in ACE mice during adulthood. On the contrary, depleting DUSP1 in CaMKII-positive neurons activates more neurons and further enhances sdC-induced behavior in ACE mice during adulthood. Also, ERK1/2 might be a downstream signal of DUSP1 in the process. Our findings reveal a role of mPFC DUSP1 in ACE-induced higher sensitivity to the drug in adult mice. DUSP1 might be a potential pharmacological target to predict or treat the susceptibility to addictive drugs caused by adolescent substance use.


Assuntos
Transtornos Relacionados ao Uso de Cocaína , Cocaína , Camundongos , Masculino , Animais , Cocaína/farmacologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Córtex Pré-Frontal , Neurônios/metabolismo
12.
Arterioscler Thromb Vasc Biol ; 44(3): 666-689, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38299356

RESUMO

BACKGROUND: Endothelial cells are constantly exposed to mechanical forces in the form of fluid shear stress, extracellular stiffness, and cyclic strain. The mechanoresponsive activity of YAP (Yes-associated protein) and its role in vascular development are well described; however, whether changes to transcription or epigenetic regulation of YAP are involved in these processes remains unanswered. Furthermore, how mechanical forces are transduced to the nucleus to drive transcriptional reprogramming in endothelial cells is poorly understood. The YAP target gene, AmotL2 (angiomotin-like 2), is a junctional mechanotransducer that connects cell-cell junctions to the nuclear membrane via the actin cytoskeleton. METHODS: We applied mechanical manipulations including shear flow, stretching, and substrate stiffness to endothelial cells to investigate the role of mechanical forces in modulating YAP transcription. Using in vitro and in vivo endothelial depletion of AmotL2, we assess nuclear morphology, chromatin organization (using transposase-accessible chromatin sequencing), and whole-mount immunofluorescent staining of the aorta to determine the regulation and functionality of YAP. Finally, we use genetic and chemical inhibition to uncouple the nuclear-cytoskeletal connection to investigate the role of this pathway on YAP transcription. RESULTS: Our results reveal that mechanical forces sensed at cell-cell junctions by the YAP target gene AmotL2 are directly involved in changes in global chromatin accessibility and activity of the histone methyltransferase EZH2, leading to modulation of YAP promotor activity. Functionally, shear stress-induced proliferation of endothelial cells in vivo was reliant on AmotL2 and YAP/TAZ (transcriptional coactivator with PDZ-binding motif) expression. Mechanistically, uncoupling of the nuclear-cytoskeletal connection from junctions and focal adhesions led to altered nuclear morphology, chromatin accessibility, and YAP promotor activity. CONCLUSIONS: Our findings reveal a role for AmotL2 and nuclear-cytoskeletal force transmission in modulating the epigenetic and transcriptional regulation of YAP to maintain a mechano-enforced positive feedback loop of vascular homeostasis. These findings may offer an explanation as to the proinflammatory phenotype that leads to aneurysm formation observed in AmotL2 endothelial deletion models.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Transativadores , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Transativadores/metabolismo , Mecanotransdução Celular , Células Endoteliais/metabolismo , Epigênese Genética , Cromatina
13.
Proc Natl Acad Sci U S A ; 119(49): e2211458119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36442101

RESUMO

Natural structural materials typically feature complex hierarchical anisotropic architectures, resulting in excellent damage tolerance. Such highly anisotropic structures, however, also provide an easy path for crack propagation, often leading to catastrophic fracture as evidenced, for example, by wood splitting. Here, we describe the weakly anisotropic structure of Ginkgo biloba (ginkgo) seed shell, which has excellent crack resistance in different directions. Ginkgo seed shell is composed of tightly packed polygonal sclereids with cell walls in which the cellulose microfibrils are oriented in a helicoidal pattern. We found that the sclereids contain distinct pits, special fine tubes like a "screw fastener," that interlock the helicoidal cell walls together. As a result, ginkgo seed shell demonstrates crack resistance in all directions, exhibiting specific fracture toughness that can rival other highly anisotropic natural materials, such as wood, bone, insect cuticle, and nacre. In situ characterization reveals ginkgo's unique toughening mechanism: pit-guided crack propagation. This mechanism forces the crack to depart from the weak compound middle lamella and enter into the sclereid, where the helicoidal cell wall significantly inhibits crack growth by the cleavage and breakage of the fibril-based cell walls. Ginkgo's toughening mechanism could provide guidelines for a new bioinspired strategy for the design of high-performance bulk materials.


Assuntos
Fraturas Ósseas , Ginkgo biloba , Sementes , Parede Celular , Madeira
14.
Proc Natl Acad Sci U S A ; 119(14): e2122217119, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35344434

RESUMO

SignificanceA clear mechanistic understanding of metformin's antidiabetic effects is lacking. This is because suprapharmacological concentrations of metformin have been used in most studies. Using mouse models and human primary hepatocytes, we show that metformin, at clinically relevant doses, suppresses hepatic glucose production by activating a conserved regulatory pathway encompassing let-7, TET3, and a fetal isoform of hepatocyte nuclear factor 4 alpha (HNF4α). We demonstrate that metformin no longer has potent antidiabetic actions in a liver-specific let-7 loss-of-function mouse model and that hepatic delivery of let-7 ameliorates hyperglycemia and improves glucose homeostasis. Our results thus reveal an important role of the hepatic let-7/TET3/HNF4α axis in mediating the therapeutic effects of metformin and suggest that targeting this axis may be a potential therapeutic for diabetes.


Assuntos
Hiperglicemia , Metformina , Animais , Modelos Animais de Doenças , Glucose/metabolismo , Hepatócitos/metabolismo , Hiperglicemia/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Fígado/metabolismo , Metformina/uso terapêutico , Camundongos
15.
J Infect Dis ; 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315770

RESUMO

BACKGROUND: Abnormal cervical cytology is commonly observed in women living with HIV (WLWH). METHODS: A cross-sectional study was conducted with 130 WLWH and 147 age-matched healthy controls, who underwent gynecological examinations at Beijing Ditan Hospital. The presence of abnormal cervical cytology in WLWH was predicted after performing a logistic regression analysis. RESULTS: Multivariate logistic regression revealed three independent factors, among which CD4 cell counts of more than 350 cells/µL was the protective factor, while human papillomavirus infection and abnormal vaginal pH were the risk factors. CONCLUSIONS: Vaginal microecological disorders can increase the risk of abnormal cervical cytology in WLWH.

16.
J Cell Mol Med ; 28(1): e18043, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37985432

RESUMO

This research aimed to find important genes and pathways related to cellular senescence (CS) in diabetic foot ulcers (DFU) and to estimate the possible pathways through which CS affects diabetic foot healing. The GSE80178 dataset was acquired from the Gene Expression Omnibus (GEO) database, containing six DFU and three diabetic foot skin (DFS) samples. The limma package was used to identify differentially expressed genes (DEGs). At the same time, DEGs associated with CS (CS-DEGs) were found using the CellAge database. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted on the CS-DEGs. A protein-protein interaction (PPI) network was built using the String database, and the cytoHubba plug-in within Cytoscape helped identify hub genes. Lastly, the miRNA-TF-mRNA regulatory network for these hub genes was established. In total, 66 CS-DEGs were obtained. These genes mainly focus on CS, Kaposi sarcoma-associated herpesvirus infection and Toll-like receptor signalling pathway. Eight hub genes were identified to regulate cell senescence in DFU, including TP53, SRC, SIRT1, CCND1, EZH2, CXCL8, AR and CDK4. According to miRNA-TF-mRNA regulatory network, hsa-mir-132-3p/SIRT1/EZH2 axis is involved in senescence cell accumulation in DFU.


Assuntos
Diabetes Mellitus , Pé Diabético , MicroRNAs , Humanos , Sirtuína 1/genética , Redes Reguladoras de Genes , MicroRNAs/genética , Perfilação da Expressão Gênica , RNA Mensageiro/genética , Biologia Computacional
17.
J Physiol ; 602(1): 49-71, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38156943

RESUMO

Chronic intermittent hypoxia (CIH, a model for sleep apnoea) is a major risk factor for several cardiovascular diseases. Autonomic imbalance (sympathetic overactivity and parasympathetic withdrawal) has emerged as a causal contributor of CIH-induced cardiovascular disease. Previously, we showed that CIH remodels the parasympathetic pathway. However, whether CIH induces remodelling of the cardiac sympathetic innervation remains unknown. Mice (male, C57BL/6J, 2-3 months) were exposed to either room air (RA, 21% O2 ) or CIH (alternating 21% and 5.7% O2 , every 6 min, 10 h day-1 ) for 8-10 weeks. Flat-mounts of their left and right atria were immunohistochemically labelled for tyrosine hydroxylase (TH, a sympathetic marker). Using a confocal microscope (or fluorescence microscope) and Neurlocudia 360 digitization and tracing system, we scanned both the left and right atria and quantitatively analysed the sympathetic axon density in both groups. The segmentation data was mapped onto a 3D mouse heart scaffold. Our findings indicated that CIH significantly remodelled the TH immunoreactive (-IR) innervation of the atria by increasing its density at the sinoatrial node, the auricles and the major veins attached to the atria (P < 0.05, n = 7). Additionally, CIH increased the branching points of TH-IR axons and decreased the distance between varicosities. Abnormal patterns of TH-IR axons around intrinsic cardiac ganglia were also found following CIH. We postulate that the increased sympathetic innervation may further amplify the effects of enhanced CIH-induced central sympathetic drive to the heart. Our work provides an anatomical foundation for the understanding of CIH-induced autonomic imbalance. KEY POINTS: Chronic intermittent hypoxia (CIH, a model for sleep apnoea) causes sympathetic overactivity, cardiovascular remodelling and hypertension. We determined the effect of CIH on sympathetic innervation of the mouse atria. In vivo CIH for 8-10 weeks resulted in an aberrant axonal pattern around the principal neurons within intrinsic cardiac ganglia and an increase in the density, branching point, tortuosity of catecholaminergic axons and atrial wall thickness. Utilizing mapping tool available from NIH (SPARC) Program, the topographical distribution of the catecholaminergic innervation of the atria were integrated into a novel 3D heart scaffold for precise anatomical distribution and holistic quantitative comparison between normal and CIH mice. This work provides a unique neuroanatomical understanding of the pathophysiology of CIH-induced autonomic remodelling.


Assuntos
Hipertensão , Síndromes da Apneia do Sono , Camundongos , Masculino , Animais , Camundongos Endogâmicos C57BL , Átrios do Coração/metabolismo , Hipóxia
18.
J Cell Physiol ; 239(2): e31129, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38192063

RESUMO

Myelodysplastic syndromes (MDS) are a group of heterogeneous myeloid clonal disorders characterized by ineffective hematopoiesis. Accumulating evidence has shown that macrophages (MΦs) are important components in the regulation of tumor progression and hematopoietic stem cells (HSCs). However, the roles of bone marrow (BM) MΦs in regulating normal and malignant hematopoiesis in different clinical stages of MDS are largely unknown. Age-paired patients with lower-risk MDS (N = 15), higher-risk MDS (N = 15), de novo acute myeloid leukemia (AML) (N = 15), and healthy donors (HDs) (N = 15) were enrolled. Flow cytometry analysis showed increased pro-inflammatory monocyte subsets and a decreased classically activated (M1) MΦs/alternatively activated (M2) MΦs ratio in the BM of patients with higher-risk MDS compared to lower-risk MDS. BM MФs from patients with higher-risk MDS and AML showed impaired phagocytosis activity but increased migration compared with lower-risk MDS group. AML BM MΦs showed markedly higher S100A8/A9 levels than lower-risk MDS BM MΦs. More importantly, coculture experiments suggested that the HSC supporting abilities of BM MΦs from patients with higher-risk MDS decreased, whereas the malignant cell supporting abilities increased compared with lower-risk MDS. Gene Ontology enrichment comparing BM MΦs from lower-risk MDS and higher-risk MDS for genes was involved in hematopoiesis- and immunity-related pathways. Our results suggest that BM MΦs are involved in ineffective hematopoiesis in patients with MDS, which indicates that repairing aberrant BM MΦs may represent a promising therapeutic approach for patients with MDS.


Assuntos
Infecções , Macrófagos , Síndromes Mielodisplásicas , Humanos , Medula Óssea/patologia , Hematopoese , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Macrófagos/patologia , Síndromes Mielodisplásicas/genética , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Infecções/patologia
19.
J Am Chem Soc ; 146(1): 1081-1088, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38113465

RESUMO

The first asymmetric total synthesis of the hexacyclic veatchine-type C20-diterpenoid alkaloid (-)-garryine is presented. Key steps include a Pd-catalyzed enantioselective Heck reaction, a radical cyclization, and a photoinduced C-H activation/oxazolidine formation sequence. Of note, a highly enantioselective Heck reaction developed in this work provides efficient access to 6/6/6 tricyclic compounds, in particular, containing a C19-functionalitiy, which is useful for diverse transformations.

20.
J Am Chem Soc ; 146(22): 15251-15263, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38780071

RESUMO

Glioblastoma (GBM) poses a significant therapeutic challenge due to its invasive nature and limited drug penetration through the blood-brain barrier (BBB). In response, here we present an innovative biomimetic approach involving the development of genetically engineered exosome nanocatalysts (Mn@Bi2Se3@RGE-Exos) for efficient GBM therapy via improving the BBB penetration and enzyme-like catalytic activities. Interestingly, a photothermally activatable multiple enzyme-like reactivity is observed in such a nanosystem. Upon NIR-II light irradiation, Mn@Bi2Se3@RGE-Exos are capable of converting hydrogen peroxide into hydroxyl radicals, oxygen, and superoxide radicals, providing a peroxidase (POD), oxidase (OXD), and catalase (CAT)-like nanocatalytic cascade. This consequently leads to strong oxidative stresses to damage GBM cells. In vitro, in vivo, and proteomic analysis further reveal the potential of Mn@Bi2Se3@RGE-Exos for the disruption of cellular homeostasis, enhancement of immunological response, and the induction of cancer cell ferroptosis, showcasing a great promise in anticancer efficacy against GBM with a favorable biosafety profile. Overall, the success of this study provides a feasible strategy for future design and clinical study of stimuli-responsive nanocatalytic medicine, especially in the context of challenging brain cancers like GBM.


Assuntos
Exossomos , Glioblastoma , Raios Infravermelhos , Fototerapia , Glioblastoma/tratamento farmacológico , Glioblastoma/terapia , Humanos , Exossomos/química , Exossomos/metabolismo , Animais , Fototerapia/métodos , Camundongos , Catálise , Linhagem Celular Tumoral , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Manganês/química , Manganês/farmacologia , Barreira Hematoencefálica/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA