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1.
Toxicol Mech Methods ; : 1-9, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39104137

RESUMO

Per- and polyfluoroalkyl substances (PFASs), one of the persistent organic pollutants, have immunosuppressive effects. The evaluation of this effect has been the focus of regulatory toxicology. In this investigation, 146 PFASs (immunosuppressive or nonimmunosuppressive) and corresponding concentration gradients were collected from literature, and their structures were characterized by using Dragon descriptors. Feature importance analysis and stepwise feature elimination are used for feature selection. Three machine learning (ML) methods, namely Random Forest (RF), Extreme Gradient Boosting Machine (XGB), and Categorical Boosting Machine (CB), were utilized for model development. The model interpretability was explored by feature importance analysis and correlation analysis. The findings indicated that the three models developed have exhibited excellent performance. Among them, the best-performing RF model has an average AUC score of 0.9720 for the testing set. The results of the feature importance analysis demonstrated that concentration, SpPosA_X, IVDE, R2s, and SIC2 were the crucial molecular features. Applicability domain analysis was also performed to determine reliable prediction boundaries for the model. In conclusion, this study is the first application of ML models to investigate the immunosuppressive activity of PFASs. The variables used in the models can help understand the mechanism of the immunosuppressive activity of PFASs, allow researchers to more effectively assess the immunosuppressive potential of a large number of PFASs, and thus better guide environmental and health risk assessment efforts.

2.
Nanotechnology ; 34(32)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37137295

RESUMO

Molybdenum disulfide (MoS2) is an emerging class of new materials with a wide range of potential practical applications. However, the uncontrollability of monolayer MoS2synthesized by traditional chemical vapor deposition method and the low responsivity of MoS2photodetectors limit its further development in the field of photoelectric detection. To achieve controlled growth of monolayer MoS2and construct MoS2photodetectors with a high responsivity, we propose a novel single crystal growth strategy of high-quality MoS2by controlling the Mo to S vapor ratio near the substrate, and deposit a layer of hafnium oxide (HfO2) on the surface of MoS2to enhance the performance of the pristine metal-semiconductor-metal structure photodetector. At a reverse bias of 8 V, the HfO2passivated MoS2photodetector features an extremely high responsivity of1201AW-1,a response time of around 0.5 s, and a detectivity of7.7×1011Jones.Meanwhile, we deeply investigate the effect of the HfO2layer on the performance of the fabricated MoS2photodetector and propose a physical mechanism to interpret the obtained experiment results. These results might facilitate a better understanding on the performance modulation of the MoS2photodetectors and accelerate the development of MoS2-based optoelectronic devices.

3.
J Nanobiotechnology ; 20(1): 332, 2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35842723

RESUMO

The development of chemo/photothermal nanotherapeutic systems with excellent photothermal performance, stable drug loading, tumor targeting and strong membrane penetration still remains a challenge. To address this problem, herein a rod-like nanocomposite system (AuNR@FA-PR/PEG) forming from folic acid (FA) terminated carboxylated cyclodextrin (CD) pseudopolyrotaxane (FA-PR) and polyethylene glycol (PEG) modifying gold nanorods (AuNR) was reported. Cisplatin (CDDP) was loaded in AuNR@FA-PR/PEG via coordination bonds to prepare a rod-like pH-responsive nanosystem (AuNR@FA-PR/PEG/CDDP) with chemotherapy/photothermal therapy. The rod-like morphology of AuNR@FA-PR/PEG was characterized by transmission electron microscope. In vitro drug release experiments showed the pH-responsive of AuNR@FA-PR/PEG/CDDP. In vivo real-time imaging assays proved AuNR@FA-PR/PEG/CDDP could rapidly enrich in the tumor area and stay for a long time because of folate targeting and their rod-like morphology. In vivo photothermal imaging assays showed AuNR@FA-PR/PEG/CDDP excellent photothermal performance, the average temperature of tumor region could reach 63.5 °C after 10 min irradiation. In vitro and in vivo experiments also demonstrated that the combined therapy of chemotherapy and photothermal therapy had an outstandingly synergistic effect and improved the therapeutic efficacy comparing with chemotherapy and photothermal therapy alone. Therefore, the prepared rod-like AuNR@FA-PR/PEG/CDDP will provide a new strategy for the effective treatment of cancer.


Assuntos
Hipertermia Induzida , Nanocompostos , Neoplasias , Linhagem Celular Tumoral , Cisplatino/farmacologia , Doxorrubicina/química , Ácido Fólico/química , Humanos , Concentração de Íons de Hidrogênio , Nanocompostos/uso terapêutico , Neoplasias/tratamento farmacológico , Fototerapia/métodos , Terapia Fototérmica , Polietilenoglicóis/química
4.
Nanotechnology ; 31(25): 255101, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32143196

RESUMO

Drug delivery carriers hold tremendous promise for improving cancer treatment, and polyrotaxane (PR) has shown excellent drug-carrying properties. However, there have been some reports that, when used as a drug carrier, water-soluble PR is not easily labeled with organic fluorescent dyes. Herein, we synthesized a drug-loaded fluorescent porphyrin-terminated PR (PR-COOH) which can be used as a tracer material in drug and gene delivery. The structure, morphology and zeta potential of PR-COOH were characterized by nuclear magnetic resonance, high-resolution transmission electron microscopy and zeta potentiometry. In this research, cisplatin (CDDP) is used as a model drug. The zeta potential, drug encapsulation efficiency and drug release of CDDP-loaded PR (PR-COOH-Pt) were studied. Confocal laser scanning microscopy showed that PR-COOH could be internalized by HeLa and CT26 cells. The antitumor efficacy of PR-COOH-Pt was investigated in vitro by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and in vivo by a xenograft tumor model. The results showed that PR-COOH-Pt could significantly inhibit tumor growth; thus PR-COOH-Pt has a promising role in cancer therapy.


Assuntos
Antineoplásicos/administração & dosagem , Cisplatino/administração & dosagem , Ciclodextrinas/síntese química , Neoplasias Hepáticas/tratamento farmacológico , Poloxâmero/síntese química , Porfirinas/química , Rotaxanos/síntese química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/química , Cisplatino/farmacologia , Ciclodextrinas/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Células HeLa , Humanos , Espectroscopia de Ressonância Magnética , Camundongos , Nanopartículas , Poloxâmero/química , Rotaxanos/química , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Inflammopharmacology ; 28(2): 603-616, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31938969

RESUMO

Inflammatory bowel disease (IBD) can be caused by a variety of factors, including hereditary and environmental influences, that lead to dysfunction of the intestinal immune system. Mesenchymal stem cells (MSCs) exhibit important regulatory roles in relieving inflammation and repairing damaged tissues. Although neutrophils are important participants in the development of inflammatory reactions, they are also essential for maintaining intestinal balance during the process of mitigation of IBD by MSCs. Here, we constructed a dextran sulfate sodium (DSS)-induced mouse IBD model and evaluated the effects of treatment with human umbilical cord MSCs. Mouse body weight, faecal traits, colon/spleen gross morphology, tissue histology and immunohistochemical staining, and inflammatory factors were analysed. Magnetic beads were used to sort infiltrating neutrophils from intestinal tissues, and their phenotypes were identified. The neutrophil inflammatory environment was also simulated in vitro, and signalling pathways involved in MSC regulation of neutrophil phenotype were analysed. Human umbilical cord MSCs effectively alleviated DSS-induced weight loss, colon shortening, and intestinal mucosal injury, and reduced clinical disease activity index. The number of neutrophils that infiltrated the intestines of mice treated with human umbilical cord MSCs were decreased and polarised toward the N2 phenotype; at the same time, ERK phosphorylation was inhibited. In vitro experiments showed that addition of the ERK phosphorylation inhibitor, PD98059, down-regulated the expression of N1 neutrophils, while up-regulating that of N2 neutrophils. The colon tissues from patients with IBD were infiltrated with neutrophils. Further, relative to healthy controls, the markers of N1 neutrophils (ICAM-1, FAS, and CCL3) were highly expressed in colon tissues from patients with IBD, whereas the markers of N2 neutrophils (VEGF, CCL2, and CXCR4) were almost undetectable. In conclusion, during alleviation of IBD, human umbilical cord MSCs polarise neutrophils toward the "N2" phenotype by inhibiting activation of ERK signalling.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Doenças Inflamatórias Intestinais/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Neutrófilos/metabolismo , Animais , Sulfato de Dextrana , Modelos Animais de Doenças , Células HL-60 , Humanos , Doenças Inflamatórias Intestinais/fisiopatologia , Células-Tronco Mesenquimais/citologia , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/fisiologia , Transdução de Sinais , Cordão Umbilical/citologia
6.
Ecotoxicol Environ Saf ; 128: 171-80, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26943944

RESUMO

Octanol/water (K(OW)) and octanol/air (K(OA)) partition coefficients are two important physicochemical properties of organic substances. In current practice, K(OW) and K(OA) values of some polychlorinated biphenyls (PCBs) are measured using generator column method. Quantitative structure-property relationship (QSPR) models can serve as a valuable alternative method of replacing or reducing experimental steps in the determination of K(OW) and K(OA). In this paper, two different methods, i.e., multiple linear regression based on dragon descriptors and hologram quantitative structure-activity relationship, were used to predict generator-column-derived log K(OW) and log K(OA) values of PCBs. The predictive ability of the developed models was validated using a test set, and the performances of all generated models were compared with those of three previously reported models. All results indicated that the proposed models were robust and satisfactory and can thus be used as alternative models for the rapid assessment of the K(OW) and K(OA) of PCBs.


Assuntos
Ar , Poluentes Ambientais/química , Modelos Químicos , Octanóis/química , Bifenilos Policlorados/química , Água/química , Modelos Lineares , Relação Quantitativa Estrutura-Atividade
7.
Cent Eur J Immunol ; 39(3): 299-305, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26155139

RESUMO

Sufentanil is a new kind of opioid analgesic and acts on µ opioid receptor. In this study, we aim to investigate the effects of sufentanil on gastric cancer cell line SGC-7901, after being exposed to different concentrations of sufentanil. Gastric cancer cells were exposed to sufentanil for a predetermined time at concentrations of 0, 0.5, 5, 50 and 500 nmol/l, respectively. Cell viability at different time points after exposure to sufentanil was tested by CCK-8 assay. FDA-PI staining was used to observe membrane integrity of gastric cancer SGC7901 cells. The apoptosis of gastric cancer cells was analyzed by Annexin V-FITC/PI Flow Cytometry and the changes of the cell cycle was determined by a detection kit. As a result, cell viability decreased in a dose- and time-dependent manner. Furthermore, with the concentration of sufentanil increased, the proportion of dead and apoptotic SGC-7901 cells increased, and more cells were arrested in G2/M phase. In a word, sufentanil can inhibit the cell viability and induce the apoptosis of gastric cancer SGC-7901 cells in vitro.

8.
Chem Biol Interact ; 390: 110867, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38199259

RESUMO

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are indeed among the most well known and extensively studied Per- and polyfluoroalkyl substances (PFASs), and increasing evidence confirm their effects on human health, especially liver steatosis. Nonetheless, the molecular mechanisms of their initiation of hepatic steatosis is still elusive. Therefore, potential targets of PFOA/PFOS must be explored to ameliorate its adverse consequences. This research aims to investigate the molecular mechanisms of PFOA and PFOS-induced liver steatosis, with emphasis on identifying a potential target that links these PFASs to liver steatosis. The potential target that causes PFOA and PFOS-induced liver steatosis have been explored and determined based on molecular docking, molecular dynamics (MD) simulation, and transcriptomics analysis. In silico results show that PFOA/PFOS can form a stable binding conformation with HNF4A, and PFOA/PFOS may interact with HNF4A to affect the downstream conduction mechanism. Transcriptome data from PFOA/PFOS-induced human stem cell spheres showed that HNF4A was inhibited, suggesting that PFOA/PFOS may constrain its function. PFOS mainly down-regulated genes related to cholesterol synthesis while PFOA mainly up-regulated genes related to fatty acid ß-oxidation. This study explored the toxicological mechanism of liver steatosis caused by PFOA/PFOS. These compounds might inhibit and down-regulate HNF4A, which is the molecular initiation events (MIE) that induces liver steatosis.


Assuntos
Ácidos Alcanossulfônicos , Fígado Gorduroso , Fluorocarbonos , Humanos , Simulação de Acoplamento Molecular , Caprilatos/toxicidade , Fígado Gorduroso/induzido quimicamente , Ácidos Alcanossulfônicos/toxicidade , Fluorocarbonos/toxicidade , Perfilação da Expressão Gênica , Fator 4 Nuclear de Hepatócito/genética
9.
Int J Biol Macromol ; 278(Pt 1): 134661, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39128741

RESUMO

Hypoxia and high concentration of glutathione (GSH) in tumor seriously hinder the role of reactive oxygen species (ROS) and oxygen-dependence strategy in tumor treatment. In this work, a self-generating oxygen and self-consuming GSH hyaluronic acid (HA)-coated porphyrin nanoplatform (TAPPP@CaO2/Pt(IV)/HA) is established for enhancing photodynamic/ion/chemo targeting synergistic therapy of tumor. During the efforts of ROS production by nanosystems, a GSH consuming strategy is implemented for augmenting ROS-induced oxidative damage for synergetic cancer therapy. CaO2 in the nanosystems is decomposed into O2 and H2O2 in an acidic environment, which alleviates hypoxia and enhances the photodynamic therapy (PDT) effect. Calcium overload causes mitochondria dysfunction and induces apoptosis. Pt (IV) reacts with GSH to produce Pt (II) for chemotherapy and reduce the concentration of GSH, protecting ROS from scavenging for augmenting ROS-induced oxidative damage. In vitro and in vivo results demonstrated the self-generating oxygen and self-consuming GSH strategy can enhance ROS-dependent PDT coupled with ion/chemo synergistic therapy. The proposed strategy not only solves the long-term problem that hypoxia limits therapeutic effect of PDT, but also ameliorates the highly reducing environment of tumors. Thus the preparation of TAPPP@CaO2/Pt(IV)/HA provided a novel strategy for the effective combined therapy of cancers.

10.
Int J Mol Med ; 51(6)2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37203397

RESUMO

Ferroptosis, a novel form of regulated cell death, is characterized by the accumulation of labile iron and lipid peroxidation, and the excessive production of reactive oxygen species (ROS). Although ferroptosis lies at the center of crucial biological activities involving O2, iron and polyunsaturated fatty acids (PUFAs), which are essential for cell proliferation and growth, the interaction between these molecules could also mediate the accumulation of toxic levels of ROS and lipid peroxides, which can then cause damage to cellular membranes and ultimately result in cell death. Recent reports have indicated that ferroptosis participates in the development and progression of inflammatory bowel disease (IBD), offering a new exploratory field which may aid in the more in­depth understanding of the pathogenesis and therapeutic targets of IBD. Of note, the mitigation of the characteristic features of ferroptosis, such as depleted glutathione (GSH) levels, inactivated glutathione peroxidase 4 (GPX4), elevated levels of lipid peroxidation and iron overload significantly relieve IBD. This has attracted the attention of researches aiming to examine therapeutic agents that inhibit ferroptosis in IBD, including radical­trapping antioxidants, enzyme inhibitors, iron chelators, protein degradation inhibitors, stem cell­derived exosomes and oral N­acetylcysteine or glutathione. The present review summarizes and discusses the current data that implicate ferroptosis in the pathogenesis of IBD and its inhibition as a novel alternate therapeutic target for IBD. The mechanisms and key mediators of ferroptosis, including GSH/GPX4, PUFAs, iron and organic peroxides are also discussed. Although the field is relatively new, the therapeutic regulation of ferroptosis has exhibited promising outcomes as a novel treatment avenue for IBD.


Assuntos
Ferroptose , Doenças Inflamatórias Intestinais , Humanos , Espécies Reativas de Oxigênio/metabolismo , Peroxidação de Lipídeos , Ferro/metabolismo , Glutationa/metabolismo , Ácidos Graxos Insaturados , Doenças Inflamatórias Intestinais/tratamento farmacológico
11.
Chemosphere ; 314: 137701, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36587920

RESUMO

Fluorinated biphenyls and their analogues (FBAs) are considered new persistent organic pollutants, but their endocrine-disrupting effects are still unknown. To fill this gap, the binding probability of 44 FBAs to different nuclear hormone receptors (NHRs) was predicted using Endocrine Disruptome. And molecular similarity and network toxicology analysis were used to strengthen the docking screening. The docking results showed that FBAs could have high binding potential for various NHRs, such as estrogen receptors ß antagonism (ERß an), liver X receptors α (LXRα), estrogen receptors α (ERα), and liver X receptors ß (LXRß). The similarity analysis found that the degree of overlap of the NHR repertoire was related to the Tanimoto coefficient of FBAs. Network toxicology verified a part of docking screening results and identified endocrine-disrupting pathways worthy of attention. This study found out potential endocrine-disrupting FBAs and their vulnerable, and developed a workflow that would leverage in silico approaches including molecular docking, similarity, and network toxicology for risk prioritization of potential endocrine-disrupting compounds.


Assuntos
Disruptores Endócrinos , Receptor alfa de Estrogênio , Simulação de Acoplamento Molecular , Receptores X do Fígado , Sistema Endócrino/metabolismo , Receptor beta de Estrogênio/metabolismo , Receptores Citoplasmáticos e Nucleares , Disruptores Endócrinos/metabolismo
12.
Food Chem Toxicol ; 182: 114189, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37980977

RESUMO

Microcystin-leucine-arginine (MC-LR) is widespread in the water and food, which has suspected to be associated with adverse pregnancy outcomes. In the present study, we aim to assess the interaction between MC-LR exposure and preeclampsia development and elucidate the molecular events involved. After exposure to MC-LR during pregnancy, the mice developed hypertension and proteinuria, the typical symptoms of preeclampsia. This was associated with decreased invasiveness of placental trophoblast and vascular dysplasia caused by MC-LR through down-regulating VEGFA and TGF-ß expression via AKT/m-TOR/HIF-1α pathway. In addition, this conclusion has been confirmed in a case-control study. Significantly, the addition of Deferoxamine (DFM), a phosphorylated serine-threonine protein kinases (p-AKT) specific agonist, can antagonize the inhibitory effect of MC-LR on the expression of related proteins, which further ameliorate the migration and invasion ability of HTR-8/Svneo cells. To sum up, our study revealed the pathologic mechanism by which MC-LR lead to preeclampsia and emphasized the importance of pregnancy management.


Assuntos
Pré-Eclâmpsia , Efeitos Tardios da Exposição Pré-Natal , Animais , Feminino , Camundongos , Gravidez , Estudos de Casos e Controles , Microcistinas/toxicidade , Placenta/metabolismo , Pré-Eclâmpsia/induzido quimicamente , Pré-Eclâmpsia/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator de Crescimento Transformador beta/antagonistas & inibidores , Fator de Crescimento Transformador beta/metabolismo
13.
Chem Res Toxicol ; 25(11): 2432-42, 2012 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-23043541

RESUMO

This study aimed to determine the most significant molecular features associated with the liver specificity of the carcinogenicity of N-nitroso compounds (NOCs). Accordingly, quantitative structure-activity relationship (QSAR) analysis was performed to extract molecular information from NOCs using a topological substructural molecular descriptor (TOPS-MODE) approach. A linear discriminant analysis (LDA) model of a series of NOCs for rat liver was developed using TOPS-MODE descriptors to predict nonliver- and liver-carcinogenic NOCs. Two descriptors exclusively calculated from the molecular structures of the compounds were selected by a genetic algorithm. The descriptors were then weighted with bond distances as well as the Abraham solute descriptor partition between water and aqueous solvent systems to indicate the importance of their roles in liver specificity. The performances of the LDA model were rigorously validated by leave-one-out cross-validation and external validation, with the prediction accuracy reaching 88.3% and 80.0%, respectively. The contributions of the different molecular fragments to rat-liver specificity were computed. The results served as important information related to liver specificity and were analyzed from the chemical-molecular perspective. The resulting model can provide an efficient method to discriminate between as well as extrapolate nonliver- and liver-carcinogenic NOCs. The contribution of the entire nitrosamine molecule was determined as being responsible for the liver specificity of nitrosamine carcinogenicity. Although the QSAR showed limitations in complex hepatocarcinogenicity, the proposed method may considerably help elucidate the role of nitrosamines in liver specificity from the chemical-molecular perspective. The nature of these enzyme-substrate interactions is characterized. Insight into the chemical-structural and biological factors related to the liver-specific biological activity of NOCs is also provided.


Assuntos
Carcinógenos/toxicidade , Fígado/efeitos dos fármacos , Compostos Nitrosos/toxicidade , Algoritmos , Animais , Bioensaio , Testes de Carcinogenicidade , Bases de Dados Factuais , Estrutura Molecular , Relação Quantitativa Estrutura-Atividade , Ratos , Sensibilidade e Especificidade
14.
Ecotoxicol Environ Saf ; 84: 282-92, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22910279

RESUMO

The quantitative structure-activity relationship (QSAR) of N-nitroso compounds (NOCs) for rat liver was developed by a topological sub-structural molecular-descriptors (TOPS-MODE) approach to predict non-liver-carcinogenic and liver-carcinogenic N-nitroso compounds based on a data set of 108 NOCs. Three descriptors calculated solely from the molecular structures of the compounds were selected by enhanced replacement method (ERM) and were weighted, respectively, with atomic weight, bond dipole moments and Abraham solute descriptor partition between water and aqueous solvent systems to indicate the importance of their roles in liver specificity. A detailed discussion on these three descriptors was carried out, and the contributions of different fragments to rat-liver specificity and the interactions among fragments were analyzed. Such results can offer some useful theoretical references for understanding the chemical structural and biological factors related to the liver-specific biological activity of NOCs.


Assuntos
Carcinógenos/toxicidade , Fígado/efeitos dos fármacos , Compostos Nitrosos/toxicidade , Relação Quantitativa Estrutura-Atividade , Testes de Toxicidade/normas , Animais , Carcinógenos/química , Estrutura Molecular , Compostos Nitrosos/química , Ratos , Sensibilidade e Especificidade
15.
Chemosphere ; 290: 133366, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34933031

RESUMO

The toxic effects of per- and polyfluoroalkyl substances (PFASs) on humans are mediated by nuclear hormone receptors (NHRs). However, data on the interaction of PFASs and NHRs is limited. Endocrine Disruptome, an inverse docking tool, was used in this study to simulate the docking of 49 common PFASs with 14 different types of human NHRs. According to the findings, 25 PFASs have a high or moderately high probability of binding to more than five NHRs, with androgen receptor (AR) and mineralocorticoid receptor (MR) being the most likely target NHRs. Molecular docking analyses revealed that the binding modes of PFASs with the two NHRs were similar to those of their corresponding co-crystallized ligands. PFASs, in particular, may disrupt the endocrine system by binding to MR. This finding is consistent with epidemiological research that has linked PFASs to MR-related diseases. Our findings may contribute to a better understanding of the health risks posed by PFASs.


Assuntos
Disruptores Endócrinos , Fluorocarbonos , Disruptores Endócrinos/toxicidade , Sistema Endócrino , Fluorocarbonos/análise , Humanos , Ligantes , Simulação de Acoplamento Molecular
16.
Int Immunopharmacol ; 110: 109066, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35978512

RESUMO

BACKGROUND: Exosomes released from human umbilical cord mesenchymal stem cell (hucMSC-Ex) have been revealed to hold great potential for the development of new treatment approaches for various diseases, including inflammatory bowel disease (IBD). Lymphatic vessels are vital for IBD development and progression to colorectal cancer (CRC), as an occluded conduit for lymphatic fluid to return to the blood. OBJECTIVE: The mechanism involved remains largely unexplored. Here, we investigate the therapeutic effect of hucMSC-Ex in a mouse model of IBD during the modulation of lymphangiogenesis. METHODS: We established a dextran sulfate sodium (DSS)-induced IBD model in BALB/c mice and observed the influence of hucMSC-Ex on tissue repair, intestinal lymphatic function, changes in lymphangiogenesis, and infiltration of macrophages. We also evaluated the functional changes of human lymphatic endothelial cells (hLECs) in vitro to determine the mechanism by which hucMSC-Ex regulate lymphangiogenesis. Finally, we identified key molecules in hucMSC-Ex by sequencing, database comparison, and cell validation. RESULTS: Results showed that hucMSC-Ex alleviates IBD in mice by improving intestinal lymphatic drainage, inhibiting lymphangiogenesis, and infiltration of macrophages. Mechanistically, the miRNA sequencing results showed that miR-302d-3p was highly expressed in hucMSC-Ex and played an important role in inhibiting lymphangiogenesis by targeting Fms-related receptor tyrosine kinase 4 (FLT4). At the same time, the phosphorylation of AKT was inhibited and vascular endothelial growth factor receptor 3 (VEGFR3) was reduced. CONCLUSION: Collectively, our study suggests that hucMSC-Ex can regulate lymphangiogenesis via the miR-302d-3p/VEGFR3/AKT axis to ameliorate IBD. Our findings identify VEGFR3 as a potential therapeutic target in IBD, where tightly regulated lymphangiogenesis is crucial in its pathogenesis and progression.


Assuntos
Exossomos , Doenças Inflamatórias Intestinais , Células-Tronco Mesenquimais , MicroRNAs , Animais , Células Endoteliais , Exossomos/metabolismo , Humanos , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/terapia , Linfangiogênese , Células-Tronco Mesenquimais/metabolismo , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Cordão Umbilical , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/farmacologia
17.
J Zhejiang Univ Sci B ; 23(3): 173-188, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35261214

RESUMO

The onset of inflammatory bowel disease (IBD) involves many factors, including environmental parameters, microorganisms, and the immune system. Although research on IBD continues to expand, the specific pathogenesis mechanism is still unclear. Protein modification refers to chemical modification after protein biosynthesis, also known as post-translational modification (PTM), which causes changes in the properties and functions of proteins. Since proteins can be modified in different ways, such as acetylation, methylation, and phosphorylation, the functions of proteins in different modified states will also be different. Transitions between different states of protein or changes in modification sites can regulate protein properties and functions. Such modifications like neddylation, sumoylation, glycosylation, and acetylation can activate or inhibit various signaling pathways (e.g., nuclear factor-|κB (NF-|κB), extracellular signal-regulated kinase (ERK), and protein kinase B (AKT)) by changing the intestinal flora, regulating immune cells, modulating the release of cytokines such as interleukin-1ß (IL-||1ß), tumor necrosis factor-α (TNF|-|α), and interferon-|γ (IFN-|γ), and ultimately leading to the maintenance of the stability of the intestinal epithelial barrier. In this review, we focus on the current understanding of PTM and describe its regulatory role in the pathogenesis of IBD.


Assuntos
Doenças Inflamatórias Intestinais , Citocinas/genética , Humanos , NF-kappa B/metabolismo , Processamento de Proteína Pós-Traducional , Fator de Necrose Tumoral alfa/metabolismo
18.
Chem Res Toxicol ; 24(12): 2269-79, 2011 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-22084901

RESUMO

A linear discriminant analysis (LDA) coupled with an enhanced replacement method (ERM) was used as an alternative method to predict the carcinogenicity of N-nitroso compounds (NOCs) in rats. This presented LDA based on the topological substructural molecular descriptors (TOPS-MODE) approach was developed to predict the carcinogenic and noncarcinogenic activity on a data set of 111 NOCs with a good classification value of 90.1%. The predictive power of the LDA model was validated through an external validation set (37 compounds) with a prediction accuracy of 94.6% and a leave-one-out cross-validation procedure (LOOCV) with a good prediction of 86.5%. This methodology showed that the TOPS-MODE descriptors weighted, respectively, by bond dipole moment and Abraham solute descriptor dipolarity/polarizability affected the NOC carcinogenicity. The contributions of certain bonds and fragments to carcinogenicity were used to assess biotransformation and carcinogenic mechanisms. The positive contribution of the carbon-nitrogen single bond (between the N-nitroso group and α-carbon to the N-nitroso group) indicated that the α-hydroxylation reaction could occur at the α-carbon or otherwise not occur. Similarly, the contributions from the molecular fragment could be applied to indicate whether the fragments generated an alkylating agent. These results suggested that this approach could discriminate between carcinogenic and noncarcinogenic NOCs, thereby providing insight into the structural features and chemical factors related to NOC carcinogenicity.


Assuntos
Carcinógenos/química , Carcinógenos/toxicidade , Compostos Nitrosos/química , Algoritmos , Animais , Bases de Dados Factuais , Análise Discriminante , Compostos Nitrosos/toxicidade , Relação Quantitativa Estrutura-Atividade , Ratos
19.
Stem Cells Int ; 2021: 5583994, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859701

RESUMO

Research on mesenchymal stem cells (MSCs) starts from the earliest assumption that cells derived from the bone marrow have the ability to repair tissues. Several scientists have since documented the crucial role of bone marrow-derived MSCs (BM-MSCs) in processes such as embryonic bone and cartilage formation, adult fracture and tissue repair, and immunomodulatory activities in therapeutic applications. In addition to BM-MSCs, several sources of MSCs have been reported to possess tissue repair and immunoregulatory abilities, making them potential treatment options for many diseases. Therefore, the therapeutic potential of MSCs in various diseases including autoimmune conditions has been explored. In addition to an imbalance of T cell subsets in most patients with autoimmune diseases, they also exhibit complex disease manifestations, overlapping symptoms among diseases, and difficult treatment. MSCs can regulate T cell subsets to restore their immune homeostasis toward disease resolution in autoimmune conditions. This review summarizes the role of MSCs in relieving autoimmune diseases via the regulation of T cell phenotypes.

20.
Stem Cells Int ; 2021: 9136583, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34349805

RESUMO

Colorectal cancer (CRC) is a common malignant tumor of the gastrointestinal tract with nonobvious early symptoms and late symptoms of anemia, weight loss, and other systemic symptoms. Its morbidity and fatality rate are next only to gastric cancer, esophageal cancer, and primary liver cancer among digestive malignancies. In addition to the conventional surgical intervention, other therapies such as radiotherapy and chemotherapy and new treatment methods such as biologics and microbiological products have been introduced. As a promising cell therapy, mesenchymal stem cell (MSC) has attracted extensive research attention. MSCs are early undifferentiated pluripotent stem cells, which have the common features of stem cells, including self-replication, self-division, self-renewal, and multidirectional differentiation. MSCs come from a wide range of sources and can be extracted from a variety of tissues such as the bone marrow, umbilical cord, and fat. Current studies have shown that MSCs have a variety of biological functions such as immune regulation, tissue damage repair, and therapeutic effects on tumors such as CRC. This review outlines the overview of MSCs and CRC and summarizes the role of MSC application in CRC.

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