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1.
Hepatology ; 77(4): 1181-1197, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35849032

RESUMO

BACKGROUND AND AIMS: Liver fibrosis is a chronic disease characterized by different etiological agents; dysregulated interactions between hepatocytes and HSCs contribute to this disease. ß-arrestin 1 (ARRB1) plays an important role in liver fibrosis; however, the effect of ARRB1 on the crosstalk between hepatocytes and HSCs in liver fibrosis is unknown. The aim of this study is to investigate how ARRB1 modulates hepatocyte and HSC activation during liver fibrosis. APPROACH AND RESULTS: Normal and fibrotic human liver and serum samples were obtained. CCl 4 -induced liver fibrosis and methionine-choline deficiency-induced NASH models were constructed. Primary hepatocytes and HSCs were isolated, and human hepatic LO2 and stellate LX2 cells were used. Small extracellular vesicles (EVs) were purified, and key proteins were identified. ARRB1 was up-regulated in hepatocytes and associated with autophagic blockage in liver fibrosis. ARRB1 increased the release of hepatocyte-derived small EVs by inhibiting multivesicular body lysosomal degradation and activating Rab27A, thereby activating HSCs. Proteomic analyses showed that mannan-binding lectin serine protease 1 (MASP1) was enriched in hepatocyte-derived small EVs and activated HSCs via p38 mitogen-activated protein kinase (MAPK)/activating transcription factor 2 (ATF2) signaling. ARRB1 up-regulated MASP1 expression in hepatocytes. MASP1 promoted liver fibrosis in mice. Clinically, MASP1 expression was increased in the serum and liver tissue of patients with liver fibrosis. CONCLUSIONS: ARRB1 up-regulates the release of hepatocyte-derived MASP1-enriched small EVs by regulating the autophagic-lysosomal/multivesicular body pathway and Rab27A. Hepatocyte-derived MASP1 activates HSCs to promote liver fibrogenesis through p38 MAPK/ATF2 signaling. Thus, MASP1 is a pivotal therapeutic target in liver fibrosis.


Assuntos
Vesículas Extracelulares , Células Estreladas do Fígado , Humanos , Camundongos , Animais , Células Estreladas do Fígado/metabolismo , Proteômica , Hepatócitos/metabolismo , Cirrose Hepática/metabolismo , Fígado/patologia , Vesículas Extracelulares/metabolismo , Serina Proteases Associadas a Proteína de Ligação a Manose/efeitos adversos , Serina Proteases Associadas a Proteína de Ligação a Manose/metabolismo
2.
BMC Infect Dis ; 24(1): 638, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926648

RESUMO

BACKGROUND: This study aimed to evaluate the diagnostic abilities of the non-invasive serum biomarkers to predict liver fibrosis staging and evaluate the progress of hepatitis B. METHODS: We enrolled 433 patients with chronic HBV infection had complete medical data available for the study, who underwent percutaneous liver biopsy. The extent of fibrosis was assessed using the modified METAVIR score. The predictive values of the non-invasive serum biomarkers were evaluated by the areas under the receiving operator characteristics curves (AUROCs) with 95% confidence intervals. RESULTS: The proportion of males with progressive stages of liver fibrosis was relatively larger, and the average age of patients with cirrhosis stages is older than the non-cirrhotic stages. We found PLT, GGT, ALP, TB, FIB4 and GPR to be significantly associated with liver fibrosis in our cohort. GGT showed a sensitivity of 71.4% and specificity of 76.7% in distinguishing cirrhosis (F4) from non-cirrhotic stages (F1-3), with an AUROC of 0.775 (95%CI 0.711-0.840).The AUROCs of the GPR in distinguishing cirrhosis (F4) from non-cirrhotic stages (F1-3) was 0.794 (95%CI 0.734-0.853), but it had a lower sensitivity of 59.2%. Additionally, GGT, FIB4, and GPR could differentiate advanced fibrosis (F3-4) from non-advanced fibrosis (F1-2) among individuals with chronic hepatitis B, with AUROCs of 0.723 (95%CI 0.668-0.777), 0.729 (95%CI 0.675-0.782), and 0.760 (95%CI: 0.709-0.811) respectively. CONCLUSIONS: GGT was a better biomarker to distinguish cirrhosis (F4) from non-cirrhotic stages (F1-3), while GPR was a better biomarker to identify advanced fibrosis (F3-4) and non-advanced fibrosis (F1-2) in patients with chronic hepatitis B.


Assuntos
Biomarcadores , Hepatite B Crônica , Cirrose Hepática , Humanos , Masculino , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Cirrose Hepática/patologia , Hepatite B Crônica/sangue , Hepatite B Crônica/patologia , Hepatite B Crônica/complicações , Biomarcadores/sangue , Feminino , Pessoa de Meia-Idade , Adulto , Curva ROC , Progressão da Doença , Fígado/patologia , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Biópsia , gama-Glutamiltransferase/sangue
3.
Sheng Li Xue Bao ; 74(4): 505-512, 2022 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-35993201

RESUMO

The purpose of the present study was to investigate the effect of glutamate scavenger oxaloacetate (OA) combined with CGS21680, an adenosine A2A receptor (A2AR) agonist, on acute traumatic brain injury (TBI), and to elucidate the underlying mechanisms. C57BL/6J mice were subjected to moderate-level TBI by controlled cortical impact, and then were treated with OA, CGS21680, or OA combined with CGS21680 at acute stage of TBI. At 24 h post TBI, neurological severity score, brain water content, glutamate concentration in cerebrospinal fluid (CSF), mRNA and protein levels of IL-1ß and TNF-α, mRNA level and activity of glutamate oxaloacetate aminotransferase (GOT), and ATP level of brain tissue were detected. The results showed that neurological deficit, brain water content, glutamate concentration in CSF, and the inflammatory cytokine IL-1ß and TNF-α production were exacerbated in CGS21680 treated mice. Administrating OA suppressed the rise of both glutamate concentration in CSF and brain water content, and elevated the ATP level of cerebral tissue. More interestingly, neurological deficit, brain edema, glutamate concentration, IL-1ß and TNF-α levels were ameliorated significantly in mice treated with OA combined with CGS21680. The combined treatment exhibited better therapeutic effects than single OA treatment. We also observed that GOT activity was enhanced in single CGS21680 treatment group, and both the GOT mRNA level and GOT activity were up-regulated in early-stage combined treatment group. These results suggest that A2AR can improve the efficiency of GOT and potentiate the ability of OA to metabolize glutamate. This may be the mechanism that A2AR activation in combination group augmented the neuroprotective effect of OA rather than aggravated the brain damages. Taken together, the present study provides a new insight for the clinical treatment of TBI with A2AR agonists and OA.


Assuntos
Agonistas do Receptor A2 de Adenosina , Lesões Encefálicas Traumáticas , Fármacos Neuroprotetores , Ácido Oxaloacético , Receptor A2A de Adenosina , Agonistas do Receptor A2 de Adenosina/farmacologia , Agonistas do Receptor A2 de Adenosina/uso terapêutico , Trifosfato de Adenosina , Animais , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas/genética , Lesões Encefálicas/metabolismo , Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/genética , Lesões Encefálicas Traumáticas/metabolismo , Ácido Glutâmico , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Ácido Oxaloacético/farmacologia , Ácido Oxaloacético/uso terapêutico , RNA Mensageiro , Receptor A2A de Adenosina/genética , Receptor A2A de Adenosina/metabolismo , Fator de Necrose Tumoral alfa/genética , Água
4.
J Neuroinflammation ; 18(1): 241, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34666797

RESUMO

BACKGROUND: Cognitive impairment in the late stage of traumatic brain injury (TBI) is associated with the NOD-, LRR and pyrin domain-containing protein 3 (NLRP3) inflammasome, which plays an important role in neuroinflammation. Although classical inflammatory pathways have been well-documented in the late stage of TBI (4-8 weeks post-injury), the mechanism by which the NLRP3 inflammasome impairs cognition is still unclear. METHODS: Mice lacking the gene encoding for NLRP3 (NLRP3-knockout mice) and their wild-type littermates were used in a controlled cortical impact model of TBI. Levels of NLRP3 inflammasome and inflammatory factors such as IL-1ß and HMGB1 were detected in post-injury hippocampal tissue, as well as long-term potentiation. Behaviors were assessed by T-maze test, novel object recognition, and nesting tests. Glycyrrhizin was used to antagonize HMGB1. Calcium imaging were performed on primary neuronal cultures. RESULTS: By using the NLRP3-knockout TBI model, we found that the continuous activation of the NLRP3 inflammasome and high mobility group box 1 (HMGB1) release were closely related to cognitive impairment. We also found that inhibition of HMGB1 improved LTP reduction and cognitive function by increasing the phosphorylation level of the NMDAR1 subunit at serine 896 while reducing NLRP3 inflammasome activation. CONCLUSION: NLRP3 inflammasome damages memory in the late stage of TBI primarily through HMGB1 upregulation and provides an explanation for the long-term progression of cognitive dysfunction.


Assuntos
Lesões Encefálicas Traumáticas/metabolismo , Disfunção Cognitiva/metabolismo , Proteína HMGB1/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Lesões Encefálicas Traumáticas/patologia , Células Cultivadas , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Técnicas de Cocultura , Disfunção Cognitiva/patologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Técnicas de Cultura de Órgãos
5.
J Mol Recognit ; 34(11): e2930, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34432338

RESUMO

In this study, magnetic molecularly imprinted polymers (MMIPs) were prepared and used as sorbents for extraction of S-phenylmercapturic acid (S-PMA) from urine samples, followed by high-performance liquid chromatography ultraviolet-visible (HPLC-UV/Vis) analysis. The MMIPs were synthesized by the copolymerization reaction of (phenylthio) acetic acid (template molecule), methacrylic acid (functional monomers) and ethylene glycol dimethacrylate (cross-linkers). The morphology, structure property and surface groups of the prepared MMIPs were characterized by scan electron microscopy, transmission electron microscopy, infrared spectroscopy, X-ray diffraction pattern, thermogravimetric analyses, Brunauer-Emmett-Teller and vibrating sample magnetometer. The selectivity of the MMIPs was investigated in the presence of interferents. Various parameters affecting the S-PMA extraction efficiency were investigated, including MMIPs amount, pH, sample volume, desorption solvent, as well as extraction and desorption time. The obtained optimal parameters were as follows: MMIPs amount (20 mg), pH (3.0), sample volume (5 mL), desorption solvent (methanol/acetic acid [9/1, v/v]), extraction time (30 minutes) and desorption time (2 minutes). The method was validated according to the Food and Drug Administration Guidance for Industry on Bioanalytical Method Validation. The calibration curve for the analyte was linear in the concentration range of 0.030-1.0 mg/L (r = 0.9995). The LOD and LOQ of the method were 0.0080 and 0.0267 mg/L, respectively. The enrichment factor of the MMIPs was 5. The relative standard deviations of intra- and inter-day tests were in the range of 3.8-5.1% and 3.9-6.3%, respectively. The recoveries at three different concentrations of 0.10, 0.50 and 0.80 mg/L ranged between 95.2% and 98.6%. In addition, the MMIPs could be reused for at least eight times. The proposed method was successfully applied to the determination of S-PMA in urine samples. In addition, this developed method could be used as a tool in the early screening and clinical diagnosis of benzene intoxication.


Assuntos
Acetilcisteína/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Nanopartículas de Magnetita/química , Polímeros Molecularmente Impressos/química , Extração em Fase Sólida/métodos , Urina/química , Acetilcisteína/isolamento & purificação , Acetilcisteína/urina , Humanos
6.
FASEB J ; 33(2): 2000-2016, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30216111

RESUMO

GPCR mediator ß-arrestins (ß-arr1 and ß-arr2) regulate a variety of physiologic and pathologic processes, including hepatocellular carcinogenesis. However, the role of ß-arrestins in liver fibrosis remains unknown. ß-arr1, but not ß-arr2, was upregulated in liver fibrotic tissues in both humans and mice; moreover, autophagy was increased. ß-arr1 deficiency or autophagic inhibitor 3-methyladenine (3-MA) significantly blocked autophagy and downregulated liver fibrosis. Furthermore, ß-arr1 enhanced hepatocyte compensatory proliferation, and hepatic stellate cell growth with activation via autophagy resulted in liver fibrosis. In the fibrosis, ß-arr1 promoted nuclear translocation of Snail by downregulation of glycogen synthase kinase-3ß, and the nuclear translocation of Snail was abrogated either by ß-arr1 deficiency or by 3-MA. These results suggest that ß-arr1 promotes liver fibrosis via autophagy-mediated Snail signaling, and ß-arr1 may be a therapeutic target for liver fibrosis.-Tan, S., Lu, Y., Xu, M., Huang, X., Liu, H., Jiang, J., Wu, B. ß-Arrestin1 enhances liver fibrosis through autophagy-mediated Snail signaling.


Assuntos
Autofagia , Células Estreladas do Fígado/metabolismo , Hepatócitos/metabolismo , Cirrose Hepática/metabolismo , Transdução de Sinais , Fatores de Transcrição da Família Snail/metabolismo , beta-Arrestina 1/metabolismo , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Linhagem Celular , Feminino , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Células Estreladas do Fígado/patologia , Hepatócitos/patologia , Humanos , Cirrose Hepática/genética , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Knockout , Fatores de Transcrição da Família Snail/genética , beta-Arrestina 1/genética
7.
Biomed Chromatogr ; 34(7): e4834, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32203622

RESUMO

In this study, activated carbon/diatomite-based magnetic nancomposites (denoted as AC/DBMNs) were synthesized and applied as an adsorbent for magnetic solid-phase extraction of S-phenylmercapturic acid (S-PMA) from human urine prior to high-performance liquid chromatography. The surface morphologies and structures of AC/DBMNs were characterized by Fourier transform infrared spectroscopy, transmission and scanning electron microscopy, X-ray diffraction, Brunauer-Emmett-Teller surface area, vibrating sample magnetometer and ζ-potential measurements. The experimental parameters including sample volume, sample pH, adsorbent amount, extraction time, elution solvent and desorption time were investigated in detail. Under the optimum conditions, the method exhibited good linearity (r > 0.9993) within the concentration ranges of 0.03-1.0 mg/L. Moreover, the limits of detection and quantification were 0.01 and 0.03 mg/L, respectively. The enrichment factor was 5, and good recoveries (88.9-97.3%) with relative standard deviations in the range of 5.6-6.8% (n = 6) for inter-day and 6.3-8.1% (n = 6) for intra-day were achieved. The developed method was successfully applied to the analysis of S-PMA in urine samples. In addition, this accurate and sensitive method has great potential to be applied in the early screening and clinical diagnosis of the workers exposed to benzene.


Assuntos
Acetilcisteína/análogos & derivados , Carvão Vegetal/química , Terra de Diatomáceas/química , Nanopartículas de Magnetita/química , Extração em Fase Sólida/métodos , Acetilcisteína/isolamento & purificação , Acetilcisteína/urina , Humanos , Limite de Detecção , Modelos Lineares , Nanocompostos/química , Reprodutibilidade dos Testes
8.
J Gastroenterol Hepatol ; 34(1): 284-292, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30144357

RESUMO

BACKGROUND AND AIM: ß-Arrestins (ß-arrs) are regulators and mediators of G protein-coupled receptor signaling that are functionally involved in inflammation. Nuclear factor-κB p65 (NF-κBp65) activation has been observed early in the onset of pancreatitis. However, the effect of ß-arrs in acute pancreatitis (AP) is unclear. The aim of this study is to investigate whether ß-arrs are involved in AP through activation of NF-κBp65. METHODS: Acute pancreatitis was induced by either caerulein injection or choline-deficient supplemented with ethionine diet (CDE). ß-arr1 wild-type and ß-arr1 knockout mice were used in the experiment. The survival rate was calculated in the CDE model mice. Histological and western blot analyses were performed in the caerulein model. Inflammatory mediators were detected by real-time polymerase chain reaction in the caerulein-induced AP mice. Furthermore, AR42J and PANC-1 cell lines were used to further study the effects of ß-arr1 in caerulein-induced pancreatic cells. RESULTS: ß-Arr1 but not ß-arr2 is significantly downregulated in caerulein-induced AP in mice. Targeted deletion of ß-arr1 notably upregulated expression of the pancreatic inflammatory mediators including tumor necrosis factor α and interleukin 1ß as well as interleukin 6 and aggravated AP in caerulein-induced mice. ß-Arr1 deficiency increased mortality in mice with CDE-induced AP. Further, ß-arr1 deficiency enhanced caerulein-induced phosphorylation of NF-κBp65 both in vivo and in vitro. CONCLUSION: ß-Arr1 alleviates AP via repression of NF-κBp65 activation, and it is a potentially therapeutic target for AP.


Assuntos
Pancreatite/genética , Pancreatite/metabolismo , Fator de Transcrição RelA/antagonistas & inibidores , Fator de Transcrição RelA/metabolismo , beta-Arrestina 1/genética , beta-Arrestina 1/metabolismo , Doença Aguda , Animais , Linhagem Celular Tumoral , Ceruletídeo , Deficiência de Colina/complicações , Modelos Animais de Doenças , Regulação para Baixo , Etionina , Feminino , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Camundongos Knockout , Pancreatite/induzido quimicamente , Pancreatite/patologia , Fosforilação , Taxa de Sobrevida , Fator de Necrose Tumoral alfa/metabolismo
9.
Am J Pathol ; 185(9): 2441-53, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26362717

RESUMO

Insulin-like growth factor-1 (IGF-1) possesses the ability to attenuate intestinal damage and promote mucosal repair of colitis. ß-Arrestins, as the scaffolding proteins of G protein-coupled receptors or non-G protein-coupled receptors signaling, can be involved in IGF-1-mediated signaling pathways. However, the interaction of IGF-1 and ß-arrestin2 in the mucosal repair of experimental colitis remains unexplored. Ulcerative colitis was induced in ß-arrestin2 wild-type mice and ß-arrestin2 knockout littermates by using 3% dextran sulfate sodium for 5 days, followed by regular water consumption for 1, 2, 3, and 4 weeks to analyze the mucosal repair from experimental colitis. Disease activity index and histologic score analyses were performed. Apoptosis and proliferation were assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling and Ki-67 staining, respectively. The expressions of ß-arrestin2, phospho (p)-IGF-1R, and p-extracellular signal-regulated kinase (ERK)1/2 were examined. Furthermore, ß-arrestin2 was overexpressed or altered in HCT116 cells by transfection before IGF-1 treatment in vitro. IGF-1 and ß-arrestin2 expression was up-regulated in the repairing phase of experimental colitis. Targeted deletion of ß-arrestin2 delayed the repair of colitis by inhibiting cell proliferation without affecting the levels of IGF-1 and p-IGF-1R. The ß-arrestin2/ERK signaling pathway was involved in IGF-1-mediated mucosal repair through promoting epithelial cell and goblet cell regeneration from experimental colitis. These results indicate that IGF-1 contributes to the mucosal repair by ß-arrestin2-mediated ERK signaling in experimental colitis.


Assuntos
Apoptose/fisiologia , Arrestinas/metabolismo , Colite/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Sistema de Sinalização das MAP Quinases , Cicatrização/fisiologia , Animais , Linhagem Celular , Proliferação de Células/fisiologia , Colite/patologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Camundongos Endogâmicos C57BL , beta-Arrestinas
10.
Tumour Biol ; 36(5): 3903-10, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25577248

RESUMO

Cystatin SN (cystatin 1, CST1) is a member of the cystatin superfamily that inhibits the proteolytic activity of cysteine proteases. CST1 is a tumor biomarker that provides useful information for the diagnosis of esophageal, gastric, and colorectal carcinomas. However, the significance of CST1 in pancreatic cancer is unknown. The aim of this study was to assess whether CST1 is a potential biomarker for early diagnosis of malignant pancreatic neoplasms. Microarray analysis of mRNA extracted from pancreatic cancer and pancreatic normal tissues was performed. Bioinformatics revealed that CST1 was one of the highest expressed genes on the array in pancreatic cancer, compared with normal tissue. In addition, the upregulation of CST1 in pancreatic cancer and several pancreatic cancer cell lines was confirmed using real-time PCR (RT-PCR), immunohistochemistry, and Western blotting. Next, CST1 knockdown using siRNA reduced the expression of the proliferation-related proteins p-AKT and PCNA significantly, as well as colony formation and xenograft development in vitro. Consistent with this, CST1 mRNA overexpression was correlated closely with malignancy-associated proteins such as PCNA, cyclin D1, cyclin A2, and cyclin E in pancreatic cancer cell lines. In conclusion, our data suggest that CST1 might contribute to the proliferation of pancreatic cancer cells and could be a potential biomarker for the early detection of pancreatic cancer.


Assuntos
Biomarcadores Tumorais/biossíntese , Carcinogênese , Detecção Precoce de Câncer , Neoplasias Pancreáticas/genética , Cistatinas Salivares/biossíntese , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Análise em Microsséries , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , RNA Mensageiro/biossíntese , Cistatinas Salivares/genética , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Cell Mol Biol Lett ; 20(3): 466-74, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26208391

RESUMO

Neuritin is a neurotrophic factor associated with neuroplasticity. Most studies on neuritin focus on the nervous system; however, there has been no comprehensive evaluation of neuritin in non-neuronal cells. In this study, we screened 11 cell lines and found that neuritin was not expressed in bone marrowderived mesenchymal stem cells (BMSCs). Neuritin-expressing BMSCs were obtained by transfection. In the neuritin-expressing BMSC model, we observed significantly greater cell migration and improved anti-senescence protection, in addition to reduced proliferation and viability. In conclusion, neuritin not only plays an important role in the nervous system but also has an effect on the migration, senescence, proliferation, and viability of stem cells. This study provides a theoretical basis for understanding the function of neuritin.


Assuntos
Movimento Celular/genética , Proliferação de Células/genética , Senescência Celular/genética , Células-Tronco Mesenquimais/metabolismo , Neuropeptídeos/genética , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Células Cultivadas , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Expressão Gênica , Células HEK293 , Células HeLa , Humanos , Imuno-Histoquímica , Células-Tronco Mesenquimais/citologia , Neuropeptídeos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Am J Physiol Gastrointest Liver Physiol ; 307(11): G1033-43, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25301184

RESUMO

Radiation-induced gastrointestinal (GI) syndrome currently has no effective prophylactic or therapeutic treatment. Previous studies and our data have demonstrated the important role of p53 in acute radiation-induced GI syndrome in mice. Many cytokines, such as tumor necrosis factor-α and fibroblast growth factor (bFGF), have been found to protect against radiation-induced intestinal injury, although the underlying mechanisms remain to be identified. Here, we report blockage of p53 through a protein kinase B (Akt) pathway in intestinal progenitor/stem cells or crypt cells as a novel molecular mechanism of growth factor-mediated intestinal radioprotection. Treatment with platelet-derived growth factor (PDGF-BB) or bFGF activated Akt phosphorylation in the intestinal crypt, lessened intestinal crypt p53 expression, decreased radiation-induced apoptosis in mouse intestinal progenitor/stem cell marker leucine-rich repeat-containing G protein-coupled receptor 5 (Lgr5)-positive cells by an average of 50%, and increased the survival rate of mice with abdominal radiation by 3 days in average. Conversely, the Akt inhibitor perifosine obstructed growth factor-simulated Akt phosphorylation while promoting radiation-induced p53 expression in intestinal crypts. Importantly, reduced Akt phosphorylation and elevated p53 expression due to the Akt inhibitor perifosine impaired intestinal progenitor/stem cells radioprotection provided by PDGF-BB and bFGF. Consistently, PDGF-BB and bFGF both upregulated Akt activation, suppressed radiation-induced p53 expression, and abrogated radiation-induced apoptosis in IEC-6 cells, although p53 overexpression in IEC-6 cells partially counteracted the radioprotection of PDGF-BB and bFGF. Our data suggest that intestinal crypt radioprotection by PDGF-BB and bFGF is dependent on regulation of Akt/p53 signaling.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Fator 2 de Crescimento de Fibroblastos/farmacologia , Intestinos/efeitos dos fármacos , Intestinos/efeitos da radiação , Proteína Oncogênica v-akt/fisiologia , Proteínas Proto-Oncogênicas c-sis/farmacologia , Protetores contra Radiação/farmacologia , Células-Tronco/efeitos dos fármacos , Proteína Supressora de Tumor p53/fisiologia , Animais , Becaplermina , Intestinos/patologia , Camundongos , Transdução de Sinais/efeitos dos fármacos
13.
Biomed Rep ; 20(2): 23, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38169881

RESUMO

Chronic hepatitis B (CHB) and its complications still have a major role in liver-related mortality. It has been indicated that hepatic iron and steatosis may influence liver fibrosis and carcinogenesis. The present study aimed to assess the liver iron and fat in patients with CHB by MRI in order to estimate the associations among liver iron, fat and the severity and progression of liver fibrosis. In the present retrospective study, consecutive patients with CHB examined from August 2018 to August 2020 were analyzed. Liver iron and fat content were assessed by MRI, which was measured as liver iron content (LIC) and proton density fat fraction (PDFF). A total of 340 patients were included in the current study. For LIC, the median value was 1.68 mg/g and elevated LIC was seen in 122 patients (35.9%). For liver fat content, the median value of PDFF was 3.1%, while only 15.0% of patients had liver steatosis (PDFF ≥5%). Age, total bilirubin and sex were independent predictive factors of liver iron overload [odds ratio (OR)=1.036, 1.005 and 8.834, respectively]. A higher platelet count (OR=1.005) and no portal hypertension (OR=0.381) independently predicted liver steatosis. The areas under the receiver operating characteristic curves of PDFF for the identification of liver cirrhosis estimated by different non-invasive tools ranged from 0.629 to 0.704. It was concluded that iron overload was common in patients with CHB, particularly in those with older age, male sex and high total bilirubin level, and liver steatosis was less common in CHB. Liver iron and fat content analyzed by MRI may contribute to the evaluation of the severity and progression of CHB.

14.
Int J Biol Sci ; 20(7): 2658-2685, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38725851

RESUMO

Mucosal epithelial death is an essential pathological characteristic of portal hypertensive gastropathy (PHG). FADDosome can regulate mucosal homeostasis by controlling mitochondrial status and cell death. However, it remains ill-defined whether and how the FADDosome is involved in the epithelial death of PHG. The FADDosome formation, mitochondrial dysfunction, glycolysis process and NLRP3 inflammasome activation in PHG from both human sections and mouse models were investigated. NLRP3 wild-type (NLRP3-WT) and NLRP3 knockout (NLRP3-KO) littermate models, critical element inhibitors and cell experiments were utilized. The mechanism underlying FADDosome-regulated mitochondrial dysfunction and epithelial death in PHG was explored. Here, we found that FADD recruited caspase-8 and receptor-interacting serine/threonine-protein kinase 1 (RIPK1) to form the FADDosome to promote Drp1-dependent mitochondrial fission and dysfunction in PHG. Also, FADDosome modulated NOX2 signaling to strengthen Drp1-dependent mitochondrial fission and alter glycolysis as well as enhance mitochondrial reactive oxygen species (mtROS) production. Moreover, due to the dysfunction of electron transport chain (ETC) and alteration of antioxidant enzymes activity, this altered glycolysis also contributed to mtROS production. Subsequently, the enhanced mtROS production induced NLRP3 inflammasome activation to result in the epithelial pyroptosis and mucosal injury in PHG. Thus, the FADDosome-regulated pathways may provide a potential therapeutic target for PHG.


Assuntos
Proteína de Domínio de Morte Associada a Fas , Mucosa Gástrica , Hipertensão Portal , Mitocôndrias , Animais , Camundongos , Mitocôndrias/metabolismo , Proteína de Domínio de Morte Associada a Fas/metabolismo , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Hipertensão Portal/metabolismo , Hipertensão Portal/patologia , Masculino , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Camundongos Knockout , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Inflamassomos/metabolismo
15.
Clin Transl Med ; 14(4): e1653, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38616702

RESUMO

INTRODUCTION: Hypoxia is an important characteristic of gastric mucosal diseases, and hypoxia-inducible factor-1α (HIF-1α) contributes to microenvironment disturbance and metabolic spectrum abnormalities. However, the underlying mechanism of HIF-1α and its association with mitochondrial dysfunction in gastric mucosal lesions under hypoxia have not been fully clarified. OBJECTIVES: To evaluate the effects of hypoxia-induced HIF-1α on the development of gastric mucosal lesions. METHODS: Portal hypertensive gastropathy (PHG) and gastric cancer (GC) were selected as representative diseases of benign and malignant gastric lesions, respectively. Gastric tissues from patients diagnosed with the above diseases were collected. Portal hypertension (PHT)-induced mouse models in METTL3 mutant or NLRP3-deficient littermates were established, and nude mouse gastric graft tumour models with relevant inhibitors were generated. The mechanisms underlying hypoxic condition, mitochondrial dysfunction and metabolic alterations in gastric mucosal lesions were further analysed. RESULTS: HIF-1α, which can mediate mitochondrial dysfunction via upregulation of METTL3/IGF2BP3-dependent dynamin-related protein 1 (Drp1) N6-methyladenosine modification to increase mitochondrial reactive oxygen species (mtROS) production, was elevated under hypoxic conditions in human and mouse portal hypertensive gastric mucosa and GC tissues. While blocking HIF-1α with PX-478, inhibiting Drp1-dependent mitochondrial fission via mitochondrial division inhibitor 1 (Mdivi-1) treatment or METTL3 mutation alleviated this process. Furthermore, HIF-1α influenced energy metabolism by enhancing glycolysis via lactate dehydrogenase A. In addition, HIF-1α-induced Drp1-dependent mitochondrial fission also enhanced glycolysis. Drp1-dependent mitochondrial fission and enhanced glycolysis were associated with alterations in antioxidant enzyme activity and dysfunction of the mitochondrial electron transport chain, resulting in massive mtROS production, which was needed for activation of NLRP3 inflammasome to aggravate the development of the PHG and GC. CONCLUSIONS: Under hypoxic conditions, HIF-1α enhances mitochondrial dysfunction via Drp1-dependent mitochondrial fission and influences the metabolic profile by altering glycolysis to increase mtROS production, which can trigger NLRP3 inflammasome activation and mucosal microenvironment alterations to contribute to the development of benign and malignant gastric mucosal lesions.


Assuntos
Doenças Mitocondriais , Neoplasias Gástricas , Animais , Humanos , Camundongos , Antioxidantes , Inflamassomos , Metiltransferases , Proteína 3 que Contém Domínio de Pirina da Família NLR , Neoplasias Gástricas/genética , Microambiente Tumoral
16.
IEEE Trans Vis Comput Graph ; 30(1): 573-583, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37878443

RESUMO

Quantum computing is a rapidly evolving field that enables exponential speed-up over classical algorithms. At the heart of this revolutionary technology are quantum circuits, which serve as vital tools for implementing, analyzing, and optimizing quantum algorithms. Recent advancements in quantum computing and the increasing capability of quantum devices have led to the development of more complex quantum circuits. However, traditional quantum circuit diagrams suffer from scalability and readability issues, which limit the efficiency of analysis and optimization processes. In this research, we propose a novel visualization approach for large-scale quantum circuits by adopting semantic analysis to facilitate the comprehension of quantum circuits. We first exploit meta-data and semantic information extracted from the underlying code of quantum circuits to create component segmentations and pattern abstractions, allowing for easier wrangling of massive circuit diagrams. We then develop Quantivine, an interactive system for exploring and understanding quantum circuits. A series of novel circuit visualizations is designed to uncover contextual details such as qubit provenance, parallelism, and entanglement. The effectiveness of Quantivine is demonstrated through two usage scenarios of quantum circuits with up to 100 qubits and a formal user evaluation with quantum experts. A free copy of this paper and all supplemental materials are available at https://osf.io/2m9yh/?view_only=0aa1618c97244f5093cd7ce15f1431f9.

17.
Materials (Basel) ; 17(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38998353

RESUMO

Through an activation reaction sintering method, porous (Mo2/3Y1/3)2AlC ceramics were prepared by Mo, Y, Al, and graphite powders as raw materials. The phase composition, microstructure, element distribution, and pore structure characteristics were comprehensively studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), Archimedes method, and bubble point method. A detailed investigation was conducted on the influence of sintering temperature on the phase composition. Possible routes of phase transition and pore formation mechanisms during the sintering process were provided. The experimental results reveal that at 650-850 °C, transition metals react with aluminum, forming aluminum-containing intermetallics and a small amount of carbides. At 850-1250 °C, transition metals collaborate with graphite, producing transition metal carbides. Then, at 1250-1450 °C, these aluminum intermetallics interact with transition metal carbides and remaining unreacted Y, Al, and C, yielding the final product (Mo2/3Y1/3) 2AlC. Simultaneously, the pore structure alters correspondingly with the solid-phase reaction at different reaction temperatures.

18.
IEEE Trans Vis Comput Graph ; 29(6): 3009-3023, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35085083

RESUMO

The development of digitized humanity information provides a new perspective on data-oriented studies of history. Many previous studies have ignored uncertainty in the exploration of historical figures and events, which has limited the capability of researchers to capture complex processes associated with historical phenomena. We propose a visual reasoning system to support visual reasoning of uncertainty associated with spatio-temporal events of historical figures based on data from the China Biographical Database Project. We build a knowledge graph of entities extracted from a historical database to capture uncertainty generated by missing data and error. The proposed system uses an overview of chronology, a map view, and an interpersonal relation matrix to describe and analyse heterogeneous information of events. The system also includes uncertainty visualization to identify uncertain events with missing or imprecise spatio-temporal information. Results from case studies and expert evaluations suggest that the visual reasoning system is able to quantify and reduce uncertainty generated by the data.

19.
Gastroenterol Rep (Oxf) ; 11: goad032, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37293270

RESUMO

Background: Berberine effectively alleviates non-alcoholic fatty liver disease (NAFLD). Nevertheless, the mechanism is incompletely comprehended. It has been reported that SIRT1 mediates lipid metabolism in liver and berberine promotes the expression of SIRT1 in hepatocytes. We hypothesized that SIRT1 mediated the effect of berberine on NAFLD. Methods: The effects of berberine on NAFLD were evaluated in C57BL/6J mice fed a high-fat diet (HFD) and in mouse primary hepatocytes and cell lines exposed to palmitate. The change of fatty acid oxidation (FAO) and the activity of CPT1A were observed in HepG2 cells. Quantitative real-time polymerase chain reaction and Western blot were employed to observe the expression of SIRT1 and lipid metabolism-related molecules. The interaction between SIRT1 and CPT1A was investigated by using co-immunoprecipitation assay in HEK293T cells. Results: Berberine treatment attenuated hepatic steatosis, reduced triglyceride (190.1 ± 11.2 µmol/g liver vs 113.6 ± 7.6 µmol/g liver, P < 0.001) and cholesterol (11.3 ± 2.5 µmol/g liver vs 6.3 ± 0.4 µmol/g liver, P < 0.001) concentration in the liver, and improved lipid and glucose metabolism disorders compared with the HFD group. The expression of SIRT1 was reduced in the liver of NAFLD patients and mouse models. Berberine increased the expression of SIRT1 and promoted the protein level of CPT1A and its activity in HepG2 cells. SIRT1 overexpression mimicked the effect of berberine on reducing triglyceride levels in HepG2 cells, whereas SIRT1 knock-down attenuated the effect of berberine. Mechanistically, berberine increased the expression of SIRT1. SIRT1 deacetylated CPT1A at the Lys675 site, which suppressed its ubiquitin-dependent degradation, thereby promoting FAO and alleviating non-alcoholic liver steatosis. Conclusions: Berberine promoted SIRT1 deacetylation of CPT1A at the Lys675 site, which reduced the ubiquitin-dependent degradation of CPT1A and ameliorated non-alcoholic liver steatosis.

20.
IEEE Trans Vis Comput Graph ; 29(1): 756-766, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36197853

RESUMO

In history research, cohort analysis seeks to identify social structures and figure mobilities by studying the group-based behavior of historical figures. Prior works mainly employ automatic data mining approaches, lacking effective visual explanation. In this paper, we present CohortVA, an interactive visual analytic approach that enables historians to incorporate expertise and insight into the iterative exploration process. The kernel of CohortVA is a novel identification model that generates candidate cohorts and constructs cohort features by means of pre-built knowledge graphs constructed from large-scale history databases. We propose a set of coordinated views to illustrate identified cohorts and features coupled with historical events and figure profiles. Two case studies and interviews with historians demonstrate that CohortVA can greatly enhance the capabilities of cohort identifications, figure authentications, and hypothesis generation.

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