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1.
ACS Nano ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740518

RESUMO

A significant gap exists in the demand for safe and effective drugs for inflammatory bowel disease (IBD), and its associated intestinal fibrosis. As oxidative stress plays a central role in the pathogenesis of IBD, astaxanthin (AST), a good antioxidant with high safety, holds promise for treating IBD. However, the application of AST is restricted by its poor solubility and easy oxidation. Herein, different protein-based nanoparticles (NPs) are fabricated for AST loading to identify an oral nanovehicle with potential clinical applicability. Through systematic validation via molecular dynamics simulation and in vitro characterization of properties, whey protein isolate (WPI)-driven NPs using a simple preparation method without the need for cross-linking agents or emulsifiers were identified as the optimal carrier for oral AST delivery. Upon oral administration, the WPI-driven NPs, benefiting from the intrinsic pH sensitivity and mucoadhesive properties, effectively shielded AST from degradation by gastric juices and targeted release of AST at intestinal lesion sites. Additionally, the AST NPs displayed potent therapeutic efficacy in both dextran sulfate sodium (DSS)-induced acute colitis and chronic colitis-associated intestinal fibrosis by ameliorating inflammation, oxidative damage, and intestinal microecology. In conclusion, the AST WPI NPs hold a potential therapeutic value in treating inflammation and fibrosis in IBD.

2.
Cell Mol Gastroenterol Hepatol ; 17(2): 251-265, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37879407

RESUMO

BACKGROUND & AIMS: Acetaminophen (APAP) overdose is the most common cause of drug-induced liver injury worldwide. Uric acid (UA) is involved in sterile inflammation in many organs, but its role in APAP-induced liver injury remains elusive. METHODS: We quantified the concentration of UA in the serum and liver tissues of APAP-overdosed mice and explored the changes in proteins involved in UA synthesis, absorption, and degeneration on APAP stimulation. We also examined the effects of inhibiting hepatocyte UA synthesis or reabsorption on APAP-induced liver injury in mice. Furthermore, we explored the process of UA clearance by peripheral macrophages. RESULTS: APAP overdose significantly increased intrahepatic UA contents, which occurred earlier than apparent hepatocyte injury in APAP-overdosed mice. APAP overdose induced significant DNA leakage and may thereby increase the substrate of UA synthesis. APAP overdose also significantly increased the enzymatic activity of xanthine oxidase and urate oxidase and decreased the expression of the UA reabsorption transporter GLUT9 in hepatocytes. Inhibiting hepatocyte UA synthesis by febuxostat or reabsorption by hepatic-specific knockout of GLUT9 alleviated APAP-induced liver injury. Further experiments showed that monosodium urate but not soluble UA may be a major form of UA mediating hepatocyte injury. Additionally, monosodium urate further recruited circulating macrophages into the liver and then aggravated inflammation by increasing the levels of inflammatory factors and reactive oxygen species. Deletion of macrophages significantly ameliorated APAP-induced liver injury in mice. CONCLUSIONS: APAP overdose induces excessive UA production and leads to local high concentrations in the liver, which further injures cells and induces liver inflammation. Inhibiting the production of UA may be a potential therapeutic option for treating APAP-induced liver injury.


Assuntos
Acetaminofen , Doença Hepática Crônica Induzida por Substâncias e Drogas , Camundongos , Animais , Acetaminofen/efeitos adversos , Ácido Úrico/metabolismo , Ácido Úrico/farmacologia , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Hepatócitos/metabolismo , Inflamação/metabolismo
3.
IEEE Trans Vis Comput Graph ; 29(6): 2901-2913, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37030803

RESUMO

We present a novel privacy preservation strategy for aggregated visual query of decentralized data. The key idea is to imitate the flowchart of the federated learning framework, and reformulate the visualization process within a federated infrastructure. The federation of visualization is fulfilled by leveraging a shared global module that composes the encrypted externalizations of transformed visual features of data pieces in local modules. We design two implementations of federated visualization: a prediction-based scheme, and a query-based scheme. We demonstrate the effectiveness of our approach with a set of visual forms, and verify its robustness with evaluations. We report the value of federated visualization in real scenarios with an expert review.

4.
J Gastroenterol Hepatol ; 38(5): 821-829, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36967570

RESUMO

BACKGROUND AND AIM: Celastrol is extracted from Tripterygium wilfordii Hook F. It has been reported to have protective effects against various liver diseases and immune regulation of autoimmune diseases. However, little is known about whether celastrol protects against immune-mediated hepatitis. This study aimed to investigate the effect of celastrol on liver injury induced by concanavalin A (ConA) and the potential mechanisms. METHODS: Intravenous administration of ConA was applied to induce acute liver injury in mice with or without pretreatment of celastrol. The effects of celastrol on ConA-induced liver injury were further demonstrated by biochemical and histopathological assessments, immunoblotting, and flow cytometry analysis. RESULTS: Both biochemical and histopathological observations showed that pretreatment of celastrol significantly ameliorated liver injury induced by ConA. Moreover, the hepatocyte apoptosis and inflammatory responses induced by ConA were also improved in celastrol-pretreated mice. Further studies revealed that these improvements were characterized as the celastrol-mediated suppression of total interleukin (IL)-17 from liver mononuclear cells in ConA-treated mice. Flow cytometry analysis suggested that celastrol specifically decreased IL-17 production by CD4+ T cells but not by CD8+ T cells. Fundamentally, pretreatment with celastrol inhibited both the IL-6 produced by F4/80+ macrophages and the IL-6 receptor on Th17 cells in the liver, which further led to the downregulated activation of STAT3, thus accounting for blocked Th17 signaling. CONCLUSIONS: Celastrol may exhibit immune regulatory effects by regulating IL-6/STAT3-IL-17 signaling in ConA-induced hepatitis, which suggested new potentials for celastrol to be applied in treating immune-mediated liver diseases.


Assuntos
Hepatite A , Hepatite Autoimune , Hepatite , Animais , Camundongos , Concanavalina A/farmacologia , Interleucina-6 , Interleucina-17/farmacologia , Linfócitos T CD8-Positivos/patologia , Hepatite/tratamento farmacológico , Hepatite/etiologia , Hepatite/prevenção & controle , Fígado/patologia , Hepatite Autoimune/tratamento farmacológico , Hepatite Autoimune/etiologia , Hepatite Autoimune/prevenção & controle
5.
Redox Biol ; 56: 102469, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36126419

RESUMO

BACKGROUND & AIMS: Excessive inflammatory responses and oxidative stress are considered the main characteristics of inflammatory bowel disease (IBD). Endogenous hydrogen sulfide (H2S) has been reported to show anti-inflammatory activity in IBD. The main aim of this study was to explore the role of 3-mercaptopyruvate sulfurtransferase (MPST), a key enzyme that regulates endogenous H2S biosynthesis, in IBD. METHODS: Colonic MPST expression was evaluated in mice and patients with IBD. Various approaches were used to explore the concrete mechanism underlying MPST regulation of the progression of colitis through in vivo and in vitro models. RESULTS: MPST expression was markedly decreased in colonic samples from patients with ulcerative colitis (UC) or Crohn's disease (CD) and from mice treated with DSS. MPST deficiency significantly aggravated the symptoms of murine colitis, exacerbated inflammatory responses and apoptosis, and inhibited epithelium stem cell-derived organoid formation in an H2S-independent manner. Consistently, when HT29 cells were treated with TNF-α, inhibition of MPST significantly increased the expression of proinflammatory cytokines, the amount of ROS and the prevalence of apoptosis, whereas overexpression of MPST markedly improved these effects. RNA-seq analysis showed that MPST might play a role in regulating apoptosis through AKT signaling. Mechanistically, MPST directly interacted with AKT and reduced the phosphorylation of AKT. Additionally, MPST expression was positively correlated with AKT expression in human IBD samples. In addition, overexpression of AKT rescued IEC apoptosis caused by MPST deficiency, while inhibition of AKT significantly aggravated it. CONCLUSIONS: MPST protects the intestines from inflammation most likely by regulating the AKT/apoptosis axis in IECs. Our results may provide a novel therapeutic strategy for the treatment of colitis.


Assuntos
Colite , Sulfeto de Hidrogênio , Doenças Inflamatórias Intestinais , Proteínas Proto-Oncogênicas c-akt , Sulfurtransferases , Animais , Apoptose , Colite/induzido quimicamente , Colite/genética , Colite/metabolismo , Citocinas , Sulfato de Dextrana , Células Epiteliais/metabolismo , Células HT29 , Humanos , Sulfeto de Hidrogênio/metabolismo , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/metabolismo , Intestinos , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/farmacologia , Sulfurtransferases/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
6.
Hepatol Int ; 16(5): 1064-1074, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36006548

RESUMO

BACKGROUND: Metabolic associated fatty liver disease (MAFLD) is the most common chronic liver disease worldwide. The important role of urid acid (UA) in MAFLD has been widely investigated. Our previous studies unveiled the elevation of serum UA levels independently predicts an increased risk of incident MAFLD. However, the role of intrahepatic UA in MAFLD has not been investigated yet. Glucose transporter 9 (GLUT9) is a key transporter that mediates the uptake of UA in hepatocytes. METHODS: In this study, we first explored the clinical association between GLUT9 polymorphism and MAFLD. Blood samples of 247 male Chinese (127 were MAFLD patients) were collected and tested for the blood UA levels and genotype of the single nucleotide polymorphism (SNP) of GLUT9 (rs1014290). Next, Glut9 hepatic-specific knockout mice (Glut9Hep-ko) were generated to investigate the role of hepatic GLUT9 in MAFLD in male mice. RESULTS: We found that the GA/AA genotypes (rs1014290) were associated with elevated serum UA levels in MAFLD patients. Meanwhile, we found that Glut9Hep-ko mice displayed lower intrahepatic UA levels, down-regulated lipogenesis genes expressions, and attenuated MAFLD symptoms after 12 weeks of high-fat diet feeding, compared with Glut9Fl/Fl littermates. However, Glut9Hep-ko mice and wild-type littermates showed no significant difference on hepatic fatty acid oxidation or inflammation. CONCLUSIONS: Our results suggested that GLUT9 polymorphism was significantly associated with MAFLD, and hepatic-specific knockout of Glut9 significantly decreased intrahepatic contents and ameliorated diet-induced MAFLD in mice.


Assuntos
Fígado Gorduroso , Proteínas Facilitadoras de Transporte de Glucose , Ácido Úrico , Animais , Ácidos Graxos , Fígado Gorduroso/diagnóstico , Genótipo , Proteínas Facilitadoras de Transporte de Glucose/genética , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Humanos , Masculino , Camundongos , Polimorfismo de Nucleotídeo Único
7.
Inflamm Bowel Dis ; 28(6): 923-935, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35020883

RESUMO

BACKGROUND: Intestinal fibrosis is a common complication of Crohn's disease (CD) and is characterized by the excessive accumulation of extracellular matrix produced by activated myofibroblasts. Caveolin-1 (CAV1) inhibits fibrosis. However, limited data show that CAV1 affects intestinal fibrosis. METHODS: Human CD tissue samples were gained from patients with CD who underwent surgical resection of the intestine and were defined as stenotic or nonstenotic areas. A dextran sodium sulfate-induced mouse model of intestinal fibrosis was established. For in vitro experiments, we purchased CCD-18Co intestinal fibrosis cells and isolated and cultured human primary colonic fibroblasts. These fibroblasts were activated by transforming growth factor ß administration for 48 hours. In the functional experiments, a specific small interfering RNA or overexpression plasmid was transfected into fibroblasts. The messenger RNA levels of fibrosis markers, such as α-smooth muscle actin, fibronectin, connective tissue growth factor, and collagen I1α, were determined using quantitative polymerase chain reaction. Western blot analysis was applied to detect the expression of CAV1, SQSTM1/p62 (sequestosome 1), and other fibrosis markers. RESULTS: In human CD samples and the dextran sodium sulfate-induced mouse model of intestinal fibrosis, we observed a downregulation of CAV1 in fibrosis-activated areas. Mechanistically, CAV1 knockdown in both human primary colonic fibroblasts and CCD-18Co cells promoted fibroblast activation, while CAV1 overexpression inhibited fibroblast activation in vitro. We found that SQSTM1/p62 positively correlated with CAV1 expression levels in patients with CD and that it was indirectly modulated by CAV1 expression. Rescue experiments showed that CAV1 decreased primary human intestinal fibroblast activation by inhibiting fibroblast autophagy through the modulation of SQSTM1/p62. CONCLUSIONS: Our data demonstrate that CAV1 deficiency induces fibroblast activation by indirectly regulating SQSTM1/p62 to promote fibroblast autophagy. CAV1 or SQSTM1/p62 may be potential therapeutic targets for intestinal fibrosis.


Intestinal fibrosis is a common complication of Crohn's disease. In human Crohn's disease samples and a mouse model of intestinal fibrosis, we observed a downregulation of caveolin-1 (CAV1) in fibrosis-activated areas. Mechanistically, CAV1 deficiency induces fibroblast activation by indirectly regulating SQSTM1/p62 (sequestosome 1) to promote fibroblast autophagy. CAV1 or SQSTM1/p62 may be potential therapeutic targets for intestinal fibrosis.


Assuntos
Doença de Crohn , Animais , Autofagia/genética , Caveolina 1/genética , Caveolina 1/metabolismo , Doença de Crohn/complicações , Dextranos/metabolismo , Fibroblastos/metabolismo , Fibrose , Humanos , Intestinos , Camundongos , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/metabolismo
8.
Cell Death Discov ; 7(1): 244, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34531376

RESUMO

Radiation-induced liver injury (RILI) is a major complication of radiotherapy during treatment for liver cancer and other upper abdominal malignant tumors that has poor pharmacological therapeutic options. A series of pathological changes can be induced by radiation. However, the underlying mechanism of RILI remains unclear. Radiation can induce cell damage via direct energy deposition or reactive free radical generation. Cellular senescence can be observed due to the DNA damage response (DDR) caused by radiation. The senescence-associated secretory phenotype (SASP) secreted from senescent cells can cause chronic inflammation and aggravate liver dysfunction for a long time. Oxidative stress further activates the signaling pathway of the inflammatory response and affects cellular metabolism. miRNAs clearly have differential expression after radiation treatment and take part in RILI development. This review aims to systematically profile the overall mechanism of RILI and the effects of radiation on hepatocyte senescence, laying foundations for the development of new therapies.

9.
J Vis (Tokyo) ; 24(1): 101-115, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32904885

RESUMO

ABSTRACT: Hashtag data are common and easy to acquire. Thus, they are widely used in studies and visual data storytelling. For example, a recent story by China Central Television Europe depicts Brexit as a hashtag movement displayed on an animated bubble chart. However, creating such a story is usually laborious and tedious, because narrators have to switch between different tools and discuss with different collaborators. To reduce the burden, we develop a prototype system to help explore the bubbles' movement by automatically inserting animations connected to the storytelling of the video creators and the interaction of viewers to those videos. We demonstrate the usability of our method through both use cases and a semi-structured user study.

10.
IEEE Trans Vis Comput Graph ; 26(1): 1161-1171, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31443022

RESUMO

Analysts commonly investigate the data distributions derived from statistical aggregations of data that are represented by charts, such as histograms and binned scatterplots, to visualize and analyze a large-scale dataset. Aggregate queries are implicitly executed through such a process. Datasets are constantly extremely large; thus, the response time should be accelerated by calculating predefined data cubes. However, the queries are limited to the predefined binning schema of preprocessed data cubes. Such limitation hinders analysts' flexible adjustment of visual specifications to investigate the implicit patterns in the data effectively. Particularly, RSATree enables arbitrary queries and flexible binning strategies by leveraging three schemes, namely, an R-tree-based space partitioning scheme to catch the data distribution, a locality-sensitive hashing technique to achieve locality-preserving random access to data items, and a summed area table scheme to support interactive query of aggregated values with a linear computational complexity. This study presents and implements a web-based visual query system that supports visual specification, query, and exploration of large-scale tabular data with user-adjustable granularities. We demonstrate the efficiency and utility of our approach by performing various experiments on real-world datasets and analyzing time and space complexity.

11.
IEEE Trans Vis Comput Graph ; 26(1): 321-331, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31403425

RESUMO

Scatterplots are frequently scaled to fit display areas in multi-view and multi-device data analysis environments. A common method used for scaling is to enlarge or shrink the entire scatterplot together with the inside points synchronously and proportionally. This process is called geometric scaling. However, geometric scaling of scatterplots may cause a perceptual bias, that is, the perceived and physical values of visual features may be dissociated with respect to geometric scaling. For example, if a scatterplot is projected from a laptop to a large projector screen, then observers may feel that the scatterplot shown on the projector has fewer points than that viewed on the laptop. This paper presents an evaluation study on the perceptual bias of visual features in scatterplots caused by geometric scaling. The study focuses on three fundamental visual features (i.e., numerosity, correlation, and cluster separation) and three hypotheses that are formulated on the basis of our experience. We carefully design three controlled experiments by using well-prepared synthetic data and recruit participants to complete the experiments on the basis of their subjective experience. With a detailed analysis of the experimental results, we obtain a set of instructive findings. First, geometric scaling causes a bias that has a linear relationship with the scale ratio. Second, no significant difference exists between the biases measured from normally and uniformly distributed scatterplots. Third, changing the point radius can correct the bias to a certain extent. These findings can be used to inspire the design decisions of scatterplots in various scenarios.

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