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1.
Gut ; 73(3): 470-484, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38050068

RESUMO

OBJECTIVE: Metastasis is the major cause of cancer death. However, what types of heterogenous cancer cells in primary tumour and how they metastasise to the target organs remain largely undiscovered. DESIGN: We performed single-cell RNA sequencing and spatial transcriptomic analysis in primary colorectal cancer (CRC) and metastases in the liver (lCRC) or ovary (oCRC). We also conducted immunofluorescence staining and functional experiments to examine the mechanism. RESULTS: Integrative analyses of epithelial cells reveal a stem-like cell cluster with high protein tyrosine phosphatase receptor type O (PTPRO) and achaete scute-like 2 (ASCL2) expression as the metastatic culprit. This cell cluster comprising distinct subpopulations shows distinct liver or ovary metastatic preference. Population 1 (P1) cells with high delta-like ligand 4 (DLL4) and MAF bZIP transcription factor A (MAFA) expression are enriched in primary CRC and oCRC, thus may be associated with ovarian metastasis. P3 cells having a similar expression pattern as cholangiocytes are found mainly in primary CRC and lCRC, presuming to be likely the culprits that specifically metastasise to the liver. Stem-like cells interacted with cancer-associated fibroblasts and endothelial cells via the DLL4-NOTCH signalling pathway to metastasise from primary CRC to the ovary. In the oCRC microenvironment, myofibroblasts provide cancer cells with glutamine and perform a metabolic reprogramming, which may be essential for cancer cells to localise and develop in the ovary. CONCLUSION: We uncover a mechanism for organ-specific CRC metastasis.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Feminino , Humanos , Neoplasias Colorretais/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Neoplasias Hepáticas/patologia , Perfilação da Expressão Gênica , Transdução de Sinais/genética , Regulação Neoplásica da Expressão Gênica , Metástase Neoplásica/genética , Microambiente Tumoral/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo
2.
J Transl Med ; 22(1): 209, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38414025

RESUMO

BACKGROUND: Human discs large-associated protein 5 (DLGAP5) is reported to play a pivotal role in regulating the cell cycle and implicate in tumorigenesis and progression of various cancers. Our current research endeavored to explore the prognostic value, immune implication, biological function and targeting strategy of DLGAP5 in LUAD through approaches including bioinformatics, network pharmacology analysis and experimental study. METHODS: Multiple databases, including TCGA, GEO, CPTAC and Human Protein Atlas, were utilized to explore the expression and clinical significance of DLGAP5 in LUAD. The genetic alterations of DLGAP5 were assessed through cBioPortal and COSMIC databases. The relationship between DLGAP5 expression and genetic abnormalities of driver genes in LUAD was analyzed through TIMER2.0 database. CancerSEA database was utilized to explore the function of DLGAP5 in 14 different states in LUAD at single-cell resolution. GDSC database was utilized to analyze the impact of DLGAP5 on IC50 of frequently-used anti-LUAD drugs. CIBERSORT method and TIMER2.0 database was utilized to explore the relationship between DLGAP5 and tumor immune infiltration. Network pharmacology was applied to screen potential DLGAP5 inhibitor. In vitro and in vivo experiments were utilized to evaluate biological function and downstream targets of DLGAP5, and the effect of screened DLGAP5 inhibitor on LUAD growth. RESULTS: High DLGAP5 expression was commonly observed in LUAD and associated with mutation of major driver genes, poor prognosis, high IC50 values of frequently-used anti-LUAD drugs, increasing immune infiltration and elevated immune checkpoint blockade-related genes in LUAD. PLK1 was revealed as a potential DLGAP5 downstream target in LUAD. DLGAP5 overexpression or knockdown significantly promoted or inhibited LUAD cell proliferation and PLK1 expression. PLK1 overexpression well rescued DLGAP5 knockdown-induced cell proliferation inhibition, or vice versa. Furthermore, by virtual screening of an investigational drug library from the DrugBank database, AT9283 was screened and identified as a novel DLGAP5 inhibitor. AT9283 effectively suppressed growth of LUAD cells both in vitro and in vivo. DLGAP5 overexpression significantly reversed AT9283-induced proliferation inhibition. Moreover, AT9283 significantly suppressed DLGAP5 and PLK1 expression, while DLGAP5 overexpression significantly reversed AT9283-induced PLK1 suppression. CONCLUSION: Our research has demonstrated that DLGAP5 is upregulated in LUAD and exhibits a strong correlation with unfavorable prognosis. Furthermore, DLGAP5 assumes a significant function in the regulation of tumor immunity and treatment outcome of immune checkpoint inhibitors. Of note, we found that DLGAP5 promotes cell proliferation of LUAD via upregulating PLK1. Targeting DLGAP5 by AT9283, our newly identified DLGAP5 inhibitor, suppresses LUAD growth. DLGAP5 may become a promising prognostic biomarker and therapeutic target for patients with LUAD.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , Ureia , Humanos , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Benzimidazóis , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Proteínas de Neoplasias , Prognóstico , Ureia/análogos & derivados
3.
Mol Ther ; 30(3): 1089-1103, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-34995801

RESUMO

N6-methyladenosine (m6A) is the most prevalent RNA modification, and the effect of its dysregulation on esophageal squamous cell carcinoma (ESCC) development remains unclear. Here, by performing transcriptome-wide m6A sequencing in 16 ESCC tissue samples, we identified the key roles of m6A in TNFRSF1A (also known as TNFR1)-mediated MAPK and NF-κB activation in ESCC. Mechanistically, a functional protein involved in m6A methylation, ATXN2, is identified that augments the translation of TNFRSF1A by binding to m6A-modified TNFRSF1A mRNA. Upregulation of the TNFRSF1A protein level, a vital upstream switch for TNFRSF1A-mediated signaling events, activates the NF-κB and MAPK pathways and thus promotes ESCC development. Furthermore, TNFRSF1A m6A modifications and protein levels are upregulated in ESCC, and high levels of TNFRSF1A m6A and protein are correlated with poor ESCC patient survival. These results collectively indicate that the m6A-TNFRSF1A axis is critical for ESCC development and thus may serve as a potential druggable target.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Ataxina-2/genética , Ataxina-2/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , NF-kappa B/metabolismo , RNA Mensageiro/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética
4.
Environ Sci Technol ; 56(11): 7185-7193, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34491046

RESUMO

We conducted a crossover study employing air cleaner intervention among 125 schoolchildren aged 9-12 years in a boarding school in Beijing, China. The PM concentrations were monitored, and 27 biomarkers were analyzed. We used the linear mixed-effects model to evaluate the association of intervention/time-weighted PM concentrations with biomarkers. The outcomes showed that air cleaner intervention was associated with FeNO, exhaled breath condensate (EBC) IL-1ß, and IL-6, which decreased by 12.57%, 10.83%, and 4.33%, respectively. Similar results were observed in the associations with PMs. Lag 1 day PMs had the strongest relationship with biomarkers, and significant changes were observed in biomarkers such as FEV1, FeNO, EBC 8-iso, and MCP-1. Boys showed higher percentage changes than girls, and the related biomarkers were FeNO, EBC 4-HNE, IL-1ß, IL-6, and MCP-1. The results showed that biomarkers such as FeNO, EBC IL-6, MCP-1, and 4-HNE could sensitively reflect the early abnormal response of the respiratory system under short-term PM exposure among healthy schoolchildren and indicated that (1) air cleaners exert a protective effect on children's respiratory system. (2) PM had lag and cumulative effect, lag 1 day had the greatest effect. (3) The boys were more sensitive than the girls.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Pequim , Biomarcadores , Criança , Estudos Cross-Over , Feminino , Humanos , Interleucina-6 , Pulmão , Masculino , Material Particulado/análise
5.
J Immunol ; 204(8): 2177-2191, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32169848

RESUMO

Emerging evidence suggests comprehensive immune profiling represents a highly promising, yet insufficiently tapped approach to identify potentially prognostic signatures for periodontitis. In this report, we agnostically identified a periodontitis-associated inflammatory expression network with multiple biomarkers identified within gingival crevicular fluid samples from study participants by applying principal component analysis. We identified an IL-17-dominated trait that is associated with periodontal disease and is inversely modified by the level of IL-10. IL-10 mitigated chemokine CXCL5 and CXCL1 expressions in IL-17-stimulated peripheral blood monocytic cells and peripheral blood monocytic cell-derived macrophages. Il10-deficient mice presented more bone loss, which was associated with more Il17 and IL-17-mediated chemokine and cytokine expression at the transcriptional levels in comparison with control wild-type mice in both the Porphyromonas gingivalis-induced experimental murine periodontitis and ligature-induced alveolar bone-loss models. The dampening effect of IL-10 on the excessive signaling of IL-17 appeared to be mediated by innate immune cells populations rather than by gingival epithelial cells, which are the major cell target for IL-17 signaling. Additionally, elevated IL-17 response in Il10-deficient mice specifically elicited an M1-skewing macrophage phenotype in the gingiva that was associated with the advanced bone loss in the ligature model. In summary, IL-17 dominated an inflammatory network characteristic of periodontitis, and IL-10 dampens this excessive IL-17-mediated periodontitis trait.


Assuntos
Inflamação/imunologia , Interleucina-10/imunologia , Interleucina-17/imunologia , Periodontite/imunologia , Animais , Células Cultivadas , Líquido do Sulco Gengival/imunologia , Humanos , Interleucina-10/deficiência , Interleucina-10/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Análise de Componente Principal
6.
J Periodontal Res ; 56(6): 1046-1057, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34368962

RESUMO

BACKGROUND AND OBJECTIVES: Plakophilin-2 (PKP2) is an intracellular desmosomal anchoring protein that has been implicated in a genome-wide association study, in which genetic variants of PKP2 are associated with Porphyromonas gingivalis (P.gingivalis) -dominant periodontal dysbiosis. In this study, we compared the ex vivo PKP2 expression in periodontitis gingival biopsies to periodontitis-free subjects and assessed the in vitro role of PKP2 in gingival epithelial barrier function and the mechanism by which P.gingivalis modulates PKP2 expression. MATERIAL AND METHODS: Using reverse transcription quantitative real-time PCR (RT-qPCR), we determined PKP2 mRNA expression levels in gingival biopsies collected from 11 periodontally healthy, 10 experimental gingivitis, and 10 chronic periodontitis subjects. PKP2 protein expression in gingival biopsies was detected by immunohistochemistry. We then challenged primary gingival epithelial cells with bacteria including P.gingivalis, Campylobacter rectus, and various Toll-like receptor agonists. Western blot and immunofluorescence staining were used to detect protein expression. Inhibitors blocking proteases pathways were tested for P.gingivalis-mediated PKP2 protein degradations. We also knocked down endogenous epithelial PKP2 using lentiviral short-hairpin RNA (shRNA) and evaluated cell proliferation, spreading, and barrier function. RESULTS: Periodontitis gingival biopsies had approximately twofold less PKP2 mRNA than did healthy controls (p < .05). PKP2 protein was predominantly expressed in gingival epithelium. In primary gingival epithelial cells, P.gingivalis challenge increased PKP2 mRNA levels, while protein expression decreased, which suggests that P.gingivalis has a protein degradation mechanism. Cysteine proteases inhibitors greatly attenuated P.gingivalis-mediated PKP2 protein degradation. Epithelial cells with deficient PKP2 exhibited inhibited cell proliferation and spreading and failed to form monolayers. Finally, P.gingivalis impaired gingival epithelial barrier function. CONCLUSIONS: PKP2 appears to be critical in maintaining gingival epithelial barrier function and is susceptible to degradation by cysteine proteases produced by P.gingivalis. Our findings have identified a mechanism by which P.gingivalis impairs epithelial barrier function by promoting PKP2 degradation.


Assuntos
Periodontite Crônica , Placofilinas , Células Epiteliais , Estudo de Associação Genômica Ampla , Gengiva , Humanos , Placofilinas/genética , Porphyromonas gingivalis
7.
Periodontol 2000 ; 82(1): 129-142, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31850627

RESUMO

Biofilm bacteria co-evolve and reach a symbiosis with the host on the gingival surface. The disruption of the homeostatic relationship between plaque bacteria and the host can initiate and promote periodontal disease progression. Recent advances in sequencing technologies allow researchers to profile disease-associated microbial communities and quantify microbial metabolic activities and host transcriptional responses. In addition to confirming the findings from previous studies, new putative pathogens and novel genes that have not previously been associated with periodontitis, emerge. For example, multiple studies have reported that Synergistetes bacteria are associated with periodontitis. Genes involved in epithelial barrier defense were downregulated in periodontitis, while excessive expression of interleukin-17 was associated with a hyperinflammatory response in periodontitis and with a unique microbial community. Bioinformatics-enabled gene ontology pathway analyses provide a panoramic view of the bacterial and host activities as they shift from periodontal health to disease. Additionally, host innate factors, such as genetic variants identified by either a candidate-gene approach or genome-wide association analyses, have an impact on subgingival bacterial colonization. Transgenic mice carrying candidate genetic variants, or with the deletion of candidate genes mimicking the deleterious loss-of-function variant effect, provide experimental evidence validating the biologic relevance of the novel markers associated with the microbial phenotype identified through a statistical approach. Further refinement in bioinformatics, data management approaches, or statistical tools, are required to gain insight into host-microbe interactions by harmonizing the multidimensional "big" data at the genomic, transcriptional, and proteomic levels.


Assuntos
Disbiose , Periodontite , Animais , Estudo de Associação Genômica Ampla , Humanos , Inflamação , Camundongos , Proteômica
8.
Periodontol 2000 ; 82(1): 93-114, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31850638

RESUMO

Inflammasomes are a group of multimolecular intracellular complexes assembled around several innate immune proteins. Recognition of a diverse range of microbial, stress and damage signals by inflammasomes results in direct activation of caspase-1, which subsequently induces the only known form of secretion of active interleukin-1ß and interleukin-18. Although the importance of interleukin-1ß in the periodontium is not questioned, the impact of inflammasomes in periodontal disease and its potential for therapeutics in periodontology is still in its very early stages. Increasing evidence in preclinical models and human data strongly implicate the involvement of inflammasomes in a number of inflammatory, autoinflammatory and autoimmune disorders. Here we review: (a) the currently known inflammasome functions, (b) clinical/preclinical data supporting inflammasome involvement in the context of periodontal and comorbid diseases and (c) potential therapies targeting inflammasomes. To clarify further the inflammasome involvement in periodontitis, we present analyses of data from a large clinical study (n = 5809) that measured the gingival crevicular fluid-interleukin-1ß and grouped the participants based on current periodontal disease classifications. We review data on 4910 European-Americans that correlate 16 polymorphisms in the interleukin-1B region with high gingival crevicular fluid-interleukin-1ß levels. We show that inflammasome components are increased in diseased periodontal tissues and that the caspase-1 inhibitor, VX-765, inhibits ~50% of alveolar bone loss in experimental periodontitis. The literature review further supports that although patients clinically present with the same phenotype, the disease that develops probably has different underlying biological pathways. The current data indicate that inflammasomes have a role in periodontal disease pathogenesis. Understanding the contribution of different inflammasomes to disease development and distinct patient susceptibility will probably translate into improved, personalized therapies.


Assuntos
Inflamassomos , Doenças Periodontais , Caspase 1 , Líquido do Sulco Gengival , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR
9.
J Cell Mol Med ; 23(11): 7566-7580, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31517441

RESUMO

Myocardial ischaemia (MI) remains a major cause of death and disability worldwide. Accumulating evidence suggests a significant role for innate immunity, in which the family of toll-like receptors (TLRs) acts as an essential player. We previously reported and reviewed the changes of Tlr expression in models of MI. However, the underlying mechanisms regulating Tlr expression in MI remain unclear. The present study first screened transcription factors (TFs) that potentially regulate Tlr gene transcription based on in silico analyses followed by experimental verification, using both in vivo and in vitro models. Forkhead box C1 (FOXC1) was identified as a putative TF, which was highly responsive to MI. Next, by focusing on two representative TLR subtypes, an intracellular subtype TLR3 and a cell-surface subtype TLR4, the regulation of FOXC1 on Tlr expression was investigated. The overexpression or knockdown of FoxC1 was observed to up- or down-regulate Tlr3/4 mRNA and protein levels, respectively. A dual-luciferase assay showed that FOXC1 trans-activated Tlr3/4 promoter, and a ChIP assay showed direct binding of FOXC1 to Tlr3/4 promoter. Last, a functional study of FOXC1 was performed, which revealed the pro-inflammatory effects of FOXC1 and its destructive effects on infarct size and heart function in a mouse model of MI. The present study for the first time identified FOXC1 as a novel regulator of Tlr expression and described its function in MI.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Isquemia Miocárdica/genética , Receptores Toll-Like/genética , Regulação para Cima/genética , Animais , Animais Recém-Nascidos , Citocinas/metabolismo , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Humanos , Inflamação/genética , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Camundongos , Regiões Promotoras Genéticas , Ligação Proteica/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Receptores Toll-Like/metabolismo
10.
J Cell Mol Med ; 22(1): 395-408, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28945004

RESUMO

Toll-like receptors (TLRs) are essential immunoreceptors involved in host defence against invading microbes. Recent studies indicate that certain TLRs activate immunological autophagy to eliminate microbes. It remains unknown whether TLRs regulate autophagy to play a role in the heart. This study examined this question. The activation of TLR3 in cultured cardiomyocytes was observed to increase protein levels of autophagic components, including LC3-II, a specific marker for autophagy induction, and p62/SQSTM1, an autophagy receptor normally degraded in the final step of autophagy. The results of transfection with a tandem mRFP-GFP-LC3 adenovirus and use of an autophagic flux inhibitor chloroquine both suggested that TLR3 in cardiomyocytes promotes autophagy induction without affecting autophagic flux. Gene-knockdown experiments showed that the TRIF-dependent pathway mediated the autophagic effect of TLR3. In the mouse model of chronic myocardial infarction, persistent autophagy was observed, concomitant with up-regulated TLR3 expression and increased TLR3-Trif signalling. Germline knockout (KO) of TLR3 inhibited autophagy, reduced infarct size, attenuated heart failure and improved survival. These protective effects were abolished by in vivo administration of an autophagy inducer rapamycin. Similar to the results obtained in cultured cardiomyocytes, TLR3-KO did not prevent autophagic flux in mouse heart. Additionally, this study failed to detect the involvement of inflammation in TLR3-KO-derived protection, as wild-type and TLR3-KO hearts were comparable in inflammatory activity. It is concluded that up-regulated TLR3 expression and signalling contributes to persistent autophagy following MI, which promotes heart failure and lethality.


Assuntos
Autofagia , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/metabolismo , Infarto do Miocárdio/complicações , Receptor 3 Toll-Like/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Autofagia/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Insuficiência Cardíaca/patologia , Camundongos Knockout , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Miócitos Cardíacos/ultraestrutura , Poli I-C/farmacologia , Ratos Sprague-Dawley , Receptor 3 Toll-Like/agonistas
11.
Hum Mol Genet ; 25(10): 2113-2129, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26962152

RESUMO

Genome-wide association studies (GWAS) of chronic periodontitis (CP) defined by clinical criteria alone have had modest success to-date. Here, we refine the CP phenotype by supplementing clinical data with biological intermediates of microbial burden (levels of eight periodontal pathogens) and local inflammatory response (gingival crevicular fluid IL-1ß) and derive periodontal complex traits (PCTs) via principal component analysis. PCTs were carried forward to GWAS (∼2.5 million markers) to identify PCT-associated loci among 975 European American adult participants of the Dental ARIC study. We sought to validate these findings for CP in the larger ARIC cohort (n = 821 participants with severe CP, 2031-moderate CP, 1914-healthy/mild disease) and an independent German sample including 717 aggressive periodontitis cases and 4210 controls. We identified six PCTs with distinct microbial community/IL-1ß structures, although with overlapping clinical presentations. PCT1 was characterized by a uniformly high pathogen load, whereas PCT3 and PCT5 were dominated by Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis, respectively. We detected genome-wide significant signals for PCT1 (CLEC19A, TRA, GGTA2P, TM9SF2, IFI16, RBMS3), PCT4 (HPVC1) and PCT5 (SLC15A4, PKP2, SNRPN). Overall, the highlighted loci included genes associated with immune response and epithelial barrier function. With the exception of associations of BEGAIN with severe and UBE3D with moderate CP, no other loci were associated with CP in ARIC or aggressive periodontitis in the German sample. Although not associated with current clinically determined periodontal disease taxonomies, upon replication and mechanistic validation these candidate loci may highlight dysbiotic microbial community structures and altered inflammatory/immune responses underlying biological sub-types of CP.


Assuntos
Periodontite Crônica/genética , Estudo de Associação Genômica Ampla , Proteínas do Tecido Nervoso/genética , Doenças Periodontais/genética , Ubiquitina-Proteína Ligases/genética , Periodontite Crônica/microbiologia , Periodontite Crônica/patologia , Feminino , Alemanha , Líquido do Sulco Gengival/microbiologia , Humanos , Inflamação/genética , Inflamação/microbiologia , Inflamação/patologia , Interleucina-1beta/genética , Masculino , Doenças Periodontais/microbiologia , Doenças Periodontais/patologia , Fenótipo , Porphyromonas gingivalis/patogenicidade , Análise de Componente Principal , Proteínas Associadas SAP90-PSD95
12.
Biochim Biophys Acta ; 1852(8): 1610-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25900786

RESUMO

Advanced glycation end-products (AGEs) comprise a group of non-enzymatic post-translational modifications of proteins and are elevated in diabetic tissues. AGE-modification impairs the digestibility of collagen in vitro but little is known about its relation to collagen-degrading proteinases in vivo. N(ε)-carboxymethyllysine (CML) is a stable AGE that forms on lysyl side-chains in the presence of glucose, probably via a transition metal-catalysed mechanism. Here, rats with streptozotocin-induced diabetes and non-diabetic controls were treated for 8weeks with placebo or the Cu(II)-selective chelator, triethylenetetramine (TETA), commencing 8weeks after disease induction. Actions of diabetes and drug treatment were measured on collagen and collagen-degrading proteinases in kidney tissue. The digestibility and CML content of collagen, and corresponding levels of mRNAs and collagen, were related to changes in collagen-degrading-proteinases. Collagen-degrading proteinases, cathepsin L (CTSL) and matrix metalloproteinase-2 (MMP-2) were increased in diabetic rats. CTSL-levels correlated strongly and positively with increased collagen-CML levels and inversely with decreased collagen digestibility in diabetes. The collagen-rich mesangium displayed a strong increase of CTSL in diabetes. TETA treatment normalised kidney collagen content and partially normalised levels of CML and CTSL. These data provide evidence for an adaptive proteinase response in diabetic kidneys, affected by excessive collagen-CML formation and decreased collagen digestibility. The normalisation of collagen and partial normalisation of CML- and CTSL-levels by TETA treatment supports the involvement of Cu(II) in CML formation and altered collagen metabolism in diabetic kidneys. Cu(II)-chelation by TETA may represent a treatment option to rectify collagen metabolism in diabetes independent of alterations in blood glucose levels.


Assuntos
Quelantes/metabolismo , Colágeno/metabolismo , Cobre/metabolismo , Diabetes Mellitus Experimental/metabolismo , Rim/metabolismo , Lisina/análogos & derivados , Peptídeo Hidrolases/metabolismo , Animais , Quelantes/farmacologia , Diabetes Mellitus Experimental/patologia , Rim/efeitos dos fármacos , Rim/patologia , Lisina/metabolismo , Masculino , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Ratos , Ratos Wistar , Estreptozocina , Trientina/farmacologia
13.
Wei Sheng Yan Jiu ; 45(5): 829-833, 2016 Sep.
Artigo em Zh | MEDLINE | ID: mdl-29903141

RESUMO

OBJECTIVE: To detect the cytotoxicity of fine particulate matter treated on human bronchial epithelial cells( BEAS-2B) and human embryonic lung fibroblasts( MRC-5) by using the method of real time cell analyze( RTCA) and Alamar Blue. METHODS: Seed the BEAS-2B cells and MRC-5 cells in the 16-well plates for RTCA analyzer and commonly 96-well plates respectively. After 24 hours, the BEAS-2B cells and the MRC-5 cells were treated by the fine particulate matter respectively in different doses( 2500, 1250, 625, 312. 5, 156. 25 and 78. 125 µg / m L). Calculating the IC50 values which determined by the two methods on different times( 3, 12, 24, 36 and 48 h). Using paired t test by SPSS 16. 0 analyse the IC50 values from two methods and estimate the correlation. RESULTS: There was correlation between the two methods, but there was no obvious difference between the two results by RTCA and Alamar Blue. CONCLUSION: There is certain cytotoxicity of fine particulate matter. At the same time, the RTCA real-time monitoring technology can be used on determination of cytotoxicity in vitro.


Assuntos
Células Epiteliais/imunologia , Células Epiteliais/patologia , Oxazinas , Material Particulado/toxicidade , Testes de Toxicidade/métodos , Xantenos , Linhagem Celular , Humanos , Material Particulado/análise
14.
FASEB J ; 28(12): 5083-96, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25138158

RESUMO

The aggregation of human amylin (hA) to form cytotoxic structures has been closely associated with the causation of type 2 diabetes. We sought to advance understanding of how altered expression and aggregation of hA might link ß-cell degeneration with diabetes onset and progression, by comparing phenotypes between homozygous and hemizygous hA-transgenic mice. The homozygous mice displayed elevated islet hA that correlated positively with measures of oligomer formation (r=0.91; P<0.0001). They also developed hyperinsulinemia with transient insulin resistance during the prediabetes stage and then underwent rapid ß-cell loss, culminating in severe juvenile-onset diabetes. The prediabetes stage was prolonged in the hemizygous mice, wherein ß-cell dysfunction and extensive oligomer formation occurred in adulthood at a much later stage, when hA levels were lower (r=-0.60; P<0.0001). This is the first report to show that hA-evoked diabetes is associated with age, insulin resistance, progressive islet dysfunction, and ß-cell apoptosis, which interact variably to cause the different diabetes syndromes. The various levels of hA elevation cause different extents of oligomer formation in the disease stages, thus eliciting early- or adult-onset diabetes syndromes, reminiscent of type 1 and 2 diabetes, respectively. Thus, the hA-evoked diabetes phenotypes differ substantively according to degree of amylin overproduction. These findings are relevant to the understanding of the pathogenesis and the development of experimental therapeutics for diabetes.


Assuntos
Biopolímeros/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/metabolismo , Animais , Sequência de Bases , Biopolímeros/química , Morte Celular , Primers do DNA , Diabetes Mellitus Tipo 2/patologia , Teste de Tolerância a Glucose , Insulina/sangue , Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Ilhotas Pancreáticas/citologia , Camundongos , Camundongos Transgênicos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Cardiovasc Diabetol ; 13: 100, 2014 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-24927960

RESUMO

BACKGROUND: Heart disease is the leading cause of death in diabetic patients, and defective copper metabolism may play important roles in the pathogenesis of diabetic cardiomyopathy (DCM). The present study sought to determine how myocardial copper status and key copper-proteins might become impaired by diabetes, and how they respond to treatment with the Cu (II)-selective chelator triethylenetetramine (TETA) in DCM. METHODS: Experiments were performed in Wistar rats with streptozotocin (STZ)-induced diabetes with or without TETA treatment. Cardiac function was analyzed in isolated-perfused working hearts, and myocardial total copper content measured by particle-induced x-ray emission spectroscopy (PIXE) coupled with Rutherford backscattering spectrometry (RBS). Quantitative expression (mRNA and protein) and/or activity of key proteins that mediate LV-tissue-copper binding and transport, were analyzed by combined RT-qPCR, western blotting, immunofluorescence microscopy, and enzyme activity assays. Statistical analysis was performed using Student's t-tests or ANOVA and p-values of < 0.05 have been considered significant. RESULTS: Left-ventricular (LV) copper levels and function were severely depressed in rats following 16-weeks' diabetes, but both were unexpectedly normalized 8-weeks after treatment with TETA was instituted. Localized myocardial copper deficiency was accompanied by decreased expression and increased polymerization of the copper-responsive transition-metal-binding metallothionein proteins (MT1/MT2), consistent with impaired anti-oxidant defences and elevated susceptibility to pro-oxidant stress. Levels of the high-affinity copper transporter-1 (CTR1) were depressed in diabetes, consistent with impaired membrane copper uptake, and were not modified by TETA which, contrastingly, renormalized myocardial copper and increased levels and cell-membrane localization of the low-affinity copper transporter-2 (CTR2). Diabetes also lowered indexes of intracellular (IC) copper delivery via the copper chaperone for superoxide dismutase (CCS) to its target cuproenzyme, superoxide dismutase-1 (SOD1): this pathway was rectified by TETA treatment, which normalized SOD1 activity with consequent bolstering of anti-oxidant defenses. Furthermore, diabetes depressed levels of additional intracellular copper-transporting proteins, including antioxidant-protein-1 (ATOX1) and copper-transporting-ATPase-2 (ATP7B), whereas TETA elevated copper-transporting-ATPase-1 (ATP7A). CONCLUSIONS: Myocardial copper deficiency and defective cellular copper transport/trafficking are revealed as key molecular defects underlying LV impairment in diabetes, and TETA-mediated restoration of copper regulation provides a potential new class of therapeutic molecules for DCM.


Assuntos
Membrana Celular/metabolismo , Quelantes/uso terapêutico , Cobre/metabolismo , Diabetes Mellitus Experimental/metabolismo , Cardiomiopatias Diabéticas/metabolismo , Animais , Membrana Celular/efeitos dos fármacos , Quelantes/farmacologia , Cobre/deficiência , Diabetes Mellitus Experimental/tratamento farmacológico , Cardiomiopatias Diabéticas/tratamento farmacológico , Masculino , Ratos , Ratos Wistar
16.
ISA Trans ; 149: 196-216, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38670904

RESUMO

In real terrain and dynamic obstacle scenarios, the complexity of the 3D UAV path planning problem greatly increases. Thus, to procure the optimal flight path for UAVs in such scenarios, an augmented Artificial Gorilla Troops Optimizer, denoted as OQMGTO, is proposed. The proposed OQMGTO algorithm introduces three strategies: combination mutation, quadratic interpolation, and random opposition-based learning, aiming to enhance the ability to timely escape from local optimal path areas and rapidly converge to the global optimal path. Given the flight distance, smoothness, terrain collision, and other five realistic factors of UAVs, specific constraint conditions are proposed to address complex scenarios, aiming to construct a path planning model. By optimizing this model, OQMGTO algorithm solves the path planning problem in complex scenarios. The extensive validation of OQMGTO algorithm on CEC2017 test suite enhances its credibility as a powerful optimization tool. Comparison experiments are conducted in simulated terrain scenarios, including six multi-obstacle terrain scenarios and three dynamic obstacle scenarios. The experimental findings validate OOMGTO algorithm can assist UAV in searching for excellent flight paths, featuring high safety and reliability characteristics, which confirms the superiority of OOMGTO algorithm for path planning in simulated terrain scenarios. Furthermore, in four flight missions carried out in real terrains, OQMGTO algorithm demonstrates superior search performance, planning smooth trajectories without mountain collision.

17.
Microorganisms ; 12(3)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38543643

RESUMO

We investigated biostimulation as an effective strategy for enhancing the degradation efficiency of recalcitrant organic compounds, with MSC14 (a novel polycyclic aromatic hydrocarbon degrading bacterium Pantoea dispersa MSC14) as the study material. Here, we investigated the impact of sodium gluconate on MSC14-mediated degradation of B[a]p. This study focused on the application of sodium gluconate, a biostimulant, on MSC14, targeting Benzo[a]pyrene (B[a]p) as the model pollutant. In this study, the novel PAHs-degrading bacterium P. dispersa MSC14 demonstrated the capability to degrade 24.41% of B[a]p after 4 days. The addition of the selected sodium gluconate stimulant at a concentration of 4 g/L stimulated MSC14 to degrade 54.85% of B[a]p after 16 h. Intermediate metabolites were analyzed using gas chromatography-mass spectrometry to infer the degradation pathway. The findings indicated that sodium gluconate promoted the intracellular transport of B[a]p by MSC14, along with the secretion of biosurfactants, enhancing emulsification and solubilization capabilities for improved B[a]p dissolution and degradation. Further analysis through transmission electron microscopy (TEM) and scanning electron microscopy (SEM) revealed the formation of a biofilm by MSC14 and an increase in flagella as a response to B[a]p stress. Transcriptome profiling elucidated the interplay of quorum sensing systems, chemotaxis systems, and flagellar systems in the degradation mechanism. Additionally, the study uncovered the molecular basis of B[a]p transport, degradation pathways, metabolic changes, and genetic regulation. In summary, the addition of sodium gluconate promotes the degradation of B[a]p by P. dispersa MSC14, offering the advantages of being rapid, efficient, and cost-effective. This research provides an economically viable approach for the remediation of petroleum hydrocarbon pollution, with broad potential applications.

18.
Cell Metab ; 36(5): 984-999.e8, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38642552

RESUMO

The relevance of biopterin metabolism in resistance to immune checkpoint blockade (ICB) therapy remains unknown. We demonstrate that the deficiency of quinoid dihydropteridine reductase (QDPR), a critical enzyme regulating biopterin metabolism, causes metabolite dihydrobiopterin (BH2) accumulation and decreases the ratio of tetrahydrobiopterin (BH4) to BH2 in pancreatic ductal adenocarcinomas (PDACs). The reduced BH4/BH2 ratio leads to an increase in reactive oxygen species (ROS) generation and a decrease in the distribution of H3K27me3 at CXCL1 promoter. Consequently, myeloid-derived suppressor cells are recruited to tumor microenvironment via CXCR2 causing resistance to ICB therapy. We discovered that BH4 supplementation is capable to restore the BH4/BH2 ratio, enhance anti-tumor immunity, and overcome ICB resistance in QDPR-deficient PDACs. Tumors with lower QDPR expression show decreased responsiveness to ICB therapy. These findings offer a novel strategy for selecting patient and combining therapies to improve the effectiveness of ICB therapy in PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/metabolismo , Humanos , Animais , Camundongos , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Microambiente Tumoral , Linhagem Celular Tumoral , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Camundongos Endogâmicos C57BL , Biopterinas/análogos & derivados , Biopterinas/metabolismo , Feminino , Masculino , Espécies Reativas de Oxigênio/metabolismo
19.
Cardiovasc Diabetol ; 12: 123, 2013 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-23981320

RESUMO

BACKGROUND: Intracellular calcium (Ca²âº) coordinates the cardiac contraction cycle and is dysregulated in diabetic cardiomyopathy. Treatment with triethylenetetramine (TETA), a divalent-copper-selective chelator, improves cardiac structure and function in patients and rats with diabetic cardiomyopathy, but the molecular basis of this action is uncertain. Here, we used TETA to probe potential linkages between left-ventricular (LV) copper and Ca²âº homeostasis, and cardiac function and structure in diabetic cardiomyopathy. METHODS: We treated streptozotocin-diabetic rats with a TETA-dosage known to ameliorate LV hypertrophy in patients with diabetic cardiomyopathy. Drug treatment was begun either one (preventative protocol) or eight (restorative protocol) weeks after diabetes induction and continued thereafter for seven or eight weeks, respectively. Total copper content of the LV wall was determined, and simultaneous measurements of intracellular calcium concentrations and isometric contraction were made in LV trabeculae isolated from control, diabetic and TETA-treated diabetic rats. RESULTS: Total myocardial copper levels became deficient in untreated diabetes but were normalized by TETA-treatment. Cardiac contractility was markedly depressed by diabetes but TETA prevented this effect. Neither diabetes nor TETA exerted significant effects on peak or resting [Ca²âº](i). However, diabetic rats showed extensive cardiac remodelling and decreased myofibrillar calcium sensitivity, consistent with observed increases in phosphorylation of troponin I, whereas these changes were all prevented by TETA. CONCLUSIONS: Diabetes causes cardiomyopathy through a copper-mediated mechanism that incorporates myocardial copper deficiency, whereas TETA treatment prevents this response and maintains the integrity of cardiac structure and myofibrillar calcium sensitivity. Altered calcium homeostasis may not be the primary defect in diabetic cardiomyopathy. Rather, a newly-described copper-mediated mechanism may cause this disease.


Assuntos
Cardiotônicos/farmacologia , Quelantes/farmacologia , Cobre/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Cardiomiopatias Diabéticas/prevenção & controle , Miocárdio/metabolismo , Trientina/farmacologia , Animais , Cálcio/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Cardiomiopatias Diabéticas/etiologia , Cardiomiopatias Diabéticas/metabolismo , Cardiomiopatias Diabéticas/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/metabolismo , Hipertrofia Ventricular Esquerda/prevenção & controle , Contração Isométrica/efeitos dos fármacos , Masculino , Contração Miocárdica/efeitos dos fármacos , Miofibrilas/efeitos dos fármacos , Miofibrilas/metabolismo , Fosforilação , Ratos , Ratos Wistar , Fatores de Tempo , Troponina I/metabolismo , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos
20.
Front Plant Sci ; 14: 1165940, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37346133

RESUMO

Rice leaf diseases are important causes of poor rice yields, and accurately identifying diseases and taking corresponding measures are important ways to improve yields. However, rice leaf diseases are diverse and varied; to address the low efficiency and high cost of manual identification, this study proposes a stacking-based integrated learning model for the efficient and accurate identification of rice leaf diseases. The stacking-based integrated learning model with four convolutional neural networks (namely, an improved AlexNet, an improved GoogLeNet, ResNet50 and MobileNetV3) as the base learners and a support vector machine (SVM) as the sublearner was constructed, and the recognition rate achieved on a rice dataset reached 99.69%. Different improvement methods have different effects on the learning and training processes for different classification tasks. To investigate the effects of different improvement methods on the accuracy of rice leaf disease diagnosis, experiments such as comparison experiments between single models and different stacking-based ensemble model combinations and comparison experiments with different datasets were executed. The model proposed in this study was shown to be more effective than single models and achieved good results on a plant dataset, providing a better method for plant disease identification.

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