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1.
Plant Cell ; 36(5): 1892-1912, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38262703

RESUMO

In cereal grains, starch is synthesized by the concerted actions of multiple enzymes on the surface of starch granules within the amyloplast. However, little is known about how starch-synthesizing enzymes access starch granules, especially for amylopectin biosynthesis. Here, we show that the rice (Oryza sativa) floury endosperm9 (flo9) mutant is defective in amylopectin biosynthesis, leading to grains exhibiting a floury endosperm with a hollow core. Molecular cloning revealed that FLO9 encodes a plant-specific protein homologous to Arabidopsis (Arabidopsis thaliana) LIKE EARLY STARVATION1 (LESV). Unlike Arabidopsis LESV, which is involved in starch metabolism in leaves, OsLESV is required for starch granule initiation in the endosperm. OsLESV can directly bind to starch by its C-terminal tryptophan (Trp)-rich region. Cellular and biochemical evidence suggests that OsLESV interacts with the starch-binding protein FLO6, and loss-of-function mutations of either gene impair ISOAMYLASE1 (ISA1) targeting to starch granules. Genetically, OsLESV acts synergistically with FLO6 to regulate starch biosynthesis and endosperm development. Together, our results identify OsLESV-FLO6 as a non-enzymatic molecular module responsible for ISA1 localization on starch granules, and present a target gene for use in biotechnology to control starch content and composition in rice endosperm.


Assuntos
Endosperma , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Amido , Oryza/genética , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Endosperma/metabolismo , Endosperma/genética , Amido/metabolismo , Amido/biossíntese , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Amilopectina/metabolismo , Mutação , Plantas Geneticamente Modificadas
2.
Plant Dis ; 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36890130

RESUMO

Peanut (Arachis hypogaea L.) is an important cash crop and oil crop around the world. In August 2021, symptoms of leaf spot were found on nearly 50% of peanut plants in the peanut planting base of Xuzhou Academy of Agriculture Sciences, Jiangsu, China. Symptoms began as small, round or oval, dark brown spots on the leaf. As the spot expanded, the center of the spot became gray to light brown and the spot was covered with small black dots. Fifteen leaves with typical symptoms were randomly collected from fifteen plants in three fields about a kilometer apart from each other. Leaf pieces (5 × 5 mm) were cut from the junction part of diseased and healthy leaf tissue, sterilized with 75% ethanol for 30 s and 5% NaClO for 30 s, washed 3 times with sterile water, placed on full strength potato dextrose agar (PDA) and incubated at 28°C in darkness. Five days after incubation, 12 isolates were obtained. Fungal colonies were white to gray on the upper surface and orange to gray on the reverse side. Conidia were single-celled, cylindrical and colorless after maturation, and were 12 - 16.5 × 4.5 - 5.5 µm (n = 50) in size. Ascospores were one-celled, hyaline, with tapering ends and one or two large guttulates at the center, and measured 9.4 - 21.5 × 4.3 - 6.4 µm (n = 50). Based on morphological characteristics, the fungi were preliminarily identified as Colletotrichum fructicola (Prihastuti et al. 2009; Rojas et al. 2010). Single spore isolates were cultured on PDA medium and two representative strains (Y18-3 and Y23-4) were selected for DNA extraction. The internal transcribed spacer (ITS) rDNA region, partial actin gene (ACT), partial calmodulin gene (CAL), partial chitin synthase gene (CHS), partial glyceraldehyde-3-phosphate dehydrogenase gene (GAPDH), and partial beta-tubulin 2 gene (TUB2) were amplified. The nucleotide sequences were submitted to Genbank (accession numbers of strain Y18-3: ITS: ON619598; ACT: ON638735; CAL: ON773430; CHS: ON773432; GAPDH: ON773436; TUB2: ON773434; accession numbers of strain Y23-4: ITS: ON620093; ACT: ON773438; CAL: ON773431; CHS: ON773433; GAPDH: ON773437; TUB2: ON773435). The phylogenetic tree was constructed using MEGA 7 based on the tandem of six genes (ITS-ACT-CAL-CHS-GAPDH-TUB2). The result showed that isolates Y18-3 and Y23-4 reside in the clade of C. fructicola species. To determine pathogenicity, conidial suspensions (107/mL) of isolate Y18-3 and Y23-4 were sprayed on ten 30-day-old healthy peanut seedlings per isolate. Five control plants were sprayed with sterile water. All plants were kept moist at 28°C in the dark (> 85% RH) for 48 h and then transferred to a moist chamber at 25°C with a 14-h photoperiod. After two weeks, typical anthracnose symptoms similar to those observed in the field appeared on leaves of inoculated plants, whereas controls remained asymptomatic. C. fructicola was re-isolated from symptomatic leaves but not from controls. Koch's postulates verified that C. fructicola was the pathogen of peanut anthracnose. C. fructicola is a well-known fungus causing anthracnose on many plant species worldwide. In recent years, new plant species infected by C. fructicola have been reported, like cherry, water hyacinth and Phoebe sheareri (Tang et al. 2021; Huang et al. 2021; Huang et al. 2022). To our knowledge, this is the first report of C. fructicola causing peanut anthracnose in China. Thus, it is recommended to pay close attention and take necessary prevention and control measures against potential spread of peanut anthracnose in China. .

3.
Sensors (Basel) ; 23(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36850511

RESUMO

Currently, three-dimensional (3D) laser-scanned point clouds have been broadly applied in many important fields, such as non-contact measurements and reverse engineering. However, it is a huge challenge to efficiently and precisely extract the boundary features of unorganized point cloud data with strong randomness and distinct uncertainty. Therefore, a novel type of boundary extraction method will be developed based on concurrent Delaunay triangular meshes (CDTMs), which adds the vertex-angles of all CDTMs around a common data point together as an evaluation index to judge whether this targeted point will appear at boundary regions. Based on the statistical analyses on the CDTM numbers of every data point, another new type of CDTM-based boundary extraction method will be further improved by filtering out most of potential non-edge points in advance. Then these two CDTM-based methods and popular α-shape method will be employed in conducting boundary extractions on several point cloud datasets for comparatively analyzing and discussing their extraction accuracies and time consumptions in detail. Finally, all obtained results can strongly demonstrate that both these two CDTM-based methods present superior accuracies and strong robustness in extracting the boundary features of various unorganized point clouds, but the statistically improved version can greatly reduce time consumption.

4.
Molecules ; 27(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35163948

RESUMO

Since the outbreak of SARS-CoV-2, numerous compounds against COVID-19 have been derived by computer-aided drug design (CADD) studies. They are valuable resources for the development of COVID-19 therapeutics. In this work, we reviewed these studies and analyzed 779 compounds against 16 target proteins from 181 CADD publications. We performed unified docking simulations and neck-to-neck comparison with the solved co-crystal structures. We computed their chemical features and classified these compounds, aiming to provide insights for subsequent drug design. Through detailed analyses, we recommended a batch of compounds that are worth further study. Moreover, we organized all the abundant data and constructed a freely available database, DrugDevCovid19, to facilitate the development of COVID-19 therapeutics.


Assuntos
Antivirais/química , Tratamento Farmacológico da COVID-19 , Desenho de Fármacos , Antivirais/uso terapêutico , Bases de Dados de Produtos Farmacêuticos , Desenvolvimento de Medicamentos , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular
5.
J Hepatol ; 75(2): 454-461, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34019941

RESUMO

Fatty liver disease associated with metabolic dysfunction is of increasing concern in mainland China, the world's most populous country. The incidence of fatty liver disease is highest in China, surpassing the incidence in European countries and the USA. An international consensus panel recently published an influential report recommending a novel definition of fatty liver disease associated with metabolic dysfunction. This recommendation includes a switch in name from non-alcoholic fatty liver disease (NAFLD) to metabolic (dysfunction)-associated fatty liver disease (MAFLD) and adoption of a set of positive criteria for disease diagnosis that are independent of alcohol intake or other liver diseases. Given the unique importance of this proposal, the Chinese Society of Hepatology (CSH) invited leading hepatologists and gastroenterologists representing their respective provinces and cities to reach consensus on alternative definitions for fatty liver disease from a national perspective. The CSH endorses the proposed change from NAFLD to MAFLD (supported by 95.45% of participants). We expect that the new definition will result in substantial improvements in health care for patients and advance disease awareness, public health policy, and political, scientific and funding outcomes for MAFLD in China.


Assuntos
Fígado Gorduroso/fisiopatologia , Gastroenterologia/tendências , China , Fígado Gorduroso/classificação , Gastroenterologia/organização & administração , Humanos
6.
J Cell Mol Med ; 24(2): 1268-1275, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31851780

RESUMO

Primary biliary cholangitis (PBC) is an autoimmune disease characterized by chronic destruction of the bile ducts. A major unanswered question regarding the pathogenesis of PBC is the precise mechanisms of small bile duct injury. Emperipolesis is one of cell-in-cell structures that is a potential histological hallmark associated with chronic hepatitis B. This study aimed to clarify the pathogenesis and characteristics of emperipolesis in PBC liver injury. Sixty-six PBC patients, diagnosed by liver biopsy combined with laboratory test, were divided into early-stage PBC (stages I and II, n = 39) and late-stage PBC (stages III and IV, n = 27). Emperipolesis was measured in liver sections stained with haematoxylin-eosin. The expressions of CK19, CD3, CD4, CD8, CD20, Ki67 and apoptosis of BECs were evaluated by immunohistochemistry or immunofluorescence double labelling. Emperipolesis was observed in 62.1% of patients with PBC, and BECs were predominantly host cells. The number of infiltrating CD3+ and CD8+ T cells correlated with the advancement of emperipolesis (R2  = 0.318, P < .001; R2  = 0.060, P < .05). The cell numbers of TUNEL-positive BECs and double staining for CK19 and Ki67 showed a significant positive correlation with emperipolesis degree (R2  = 0.236, P < .001; R2  = 0.267, P < .001). We conclude that emperipolesis mediated by CD8+ T cells appears to be relevant to apoptosis of BEC and thus may aggravate the further injury of interlobular bile ducts.


Assuntos
Apoptose , Ductos Biliares/patologia , Linfócitos T CD8-Positivos/imunologia , Emperipolese , Células Epiteliais/patologia , Cirrose Hepática Biliar/fisiopatologia , Ductos Biliares/imunologia , Ductos Biliares/lesões , Estudos de Casos e Controles , Proliferação de Células , Células Epiteliais/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Bioorg Med Chem Lett ; 28(10): 1804-1810, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29678460

RESUMO

Novel conformationally constrained BET bromodomain inhibitors have been developed. These inhibitors were optimized in two similar, yet distinct chemical series, the 6-methyl-1H-pyrrolo[2,3-c]pyridin-7(6H)-ones (A) and the 1-methyl-1H-pyrrolo[2,3-c]pyridin-7(6H)-ones (B). Each series demonstrated excellent activity in binding and cellular assays, and lead compounds from each series demonstrated significant efficacy in in vivo tumor xenograft models.


Assuntos
Proteínas Nucleares/antagonistas & inibidores , Piridonas/química , Fatores de Transcrição/antagonistas & inibidores , Animais , Sítios de Ligação , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos , Meia-Vida , Humanos , Camundongos , Microssomos/metabolismo , Simulação de Dinâmica Molecular , Mieloma Múltiplo/tratamento farmacológico , Proteínas Nucleares/metabolismo , Estrutura Terciária de Proteína , Piridonas/farmacocinética , Piridonas/farmacologia , Piridonas/uso terapêutico , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo , Transplante Heterólogo
9.
Int J Mol Sci ; 17(7)2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27428948

RESUMO

Interleukin-23 (IL-23) and its downstream factor IL-17 are the key cytokines involved in immune and inflammatory response in chronic liver diseases. This study aimed to investigate the role and molecular mechanisms of the IL-23/Th17 axis in chronic hepatitis C virus (HCV) infection, and the efficacy of IL-23/Th17 modulation in response to anti-HCV therapy. Sixty-six HCV-infected patients and 20 healthy controls were enrolled. The patients received PegIFNa-2a and ribavirin therapy for at least 48 weeks. The plasma level of IL-23 and the number of IL-17A-, IFN-γ-, and IL-21-producing peripheral blood mononuclear cells (PBMCs) at baseline and 12, 24, and 48 weeks following treatment were determined. The mRNA level of Th17 immune-associated molecules in PBMCs was evaluated by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) following treatment with IL-23 agonist or antagonist. Our data showed that, compared to healthy controls, HCV-infected patients had an increased plasma level of IL-23 and increased frequencies of IL-17A- and IFN-γ-producing PBMCs, whereas the HCV patients exhibited a reduced number of IL-21-producing PBMCs. However, the baseline frequencies of IL-21-producing PBMCs were markedly higher in HCV patients who achieved rapid virological response (RVR) than those without RVR. Additionally, the mRNA expressions of IL-21, IFN-γ, myxovirus resistance protein A (MxA), and suppressor of cytokine signaling 3 (SOCS3) were significantly upregulated in PBMCs, while FoxP3 expression was suppressed by IL-23 agonist. Thus, the IL-23/Th17 axis plays an important role in development of chronic HCV infection and antiviral response. IL-23 may enhance the antiviral activity of interferon-based therapy by modulating the expression of Th17 cells-associated molecules in HCV-infected patients.


Assuntos
Antivirais/farmacologia , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/farmacologia , Interleucina-17/metabolismo , Interleucina-23/metabolismo , Polietilenoglicóis/farmacologia , Ribavirina/farmacologia , Adolescente , Adulto , Idoso , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Hepacivirus/fisiologia , Hepatite C Crônica/metabolismo , Hepatite C Crônica/patologia , Humanos , Interleucina-17/genética , Interleucina-23/genética , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes/farmacologia , Adulto Jovem
11.
Zhonghua Gan Zang Bing Za Zhi ; 23(4): 265-9, 2015 Apr.
Artigo em Zh | MEDLINE | ID: mdl-26133817

RESUMO

OBJECTIVE: To explore the clinical application and related factors of FibroTouch in the diagnosis of liver fibrosis in patients with chronic liver disease through comparison of the specificity and sensitivity of FibroTouch and multi-parameter models, and to identify whether FibroTouch is a more accurate and safe method in diagnosis of liver fibrosis and evaluation of the therapeutic effect. METHODS: A total of 190 patients with chronic liver disease were performed liver biopsy and underwent liver stiffness measurement (LSM) using FibroTouch in department of Traditional and Western Medical Hepatology, Third Hospital of Hebei Medical University from January 2014 to February 2015. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBIL) were tested by enzymic method with automatic biochemistry analyzer. Blood platelet counts were detected by automatic blood cell analyzer. AST-to-PLT ratio index (APRI) and fibrosis index based on the 4 factor (FIB-4) were calculated. The diagnostic values of FibroTouch, APRI and FIB-4 for liver fibrosis degree were calculated and compared by receiver operating characteristic (ROC) curves. The related factors of LSM were analyzed by Spearman analysis. RESULTS: There was significant correlation between LSM and histological fibrosis (r=0.804, P=0.000). The area under ROC curve of LSM for S(≥2, S≥3 and S=4 was 0.894, 0.938 and 0.961, respectively, which was significantly higher than APRI (0.678, 0.698 and 0.658) and FIB-4 (0.765, 0.785 and 0.775). On Spearman analysis, LSM was positively correlated with age, ALT, AST, TBIL ((≥2×ULN) and the grade of liver inflammation (r=0.309, 0.558, 0.504, 0.492 and 0.532, respectively) but negatively with PLT (r=-0.444), (all P<0.05). CONCLUSIONS: LSM is a convenient and reliable approach for diagnosis of liver fibrosis in patients with chronic liver disease. The sensitivity and specificity of Fibrotouch in diagnosis of hepatic fibrosis is superior to APRI and FIB-4, and age, high level ofALT, AST and TBIL (≥2×ULN) were independent predictors of LSM inaccuracy.


Assuntos
Cirrose Hepática , Alanina Transaminase , Aspartato Aminotransferases , Bilirrubina , Biomarcadores , Biópsia , Doença Crônica , Humanos , Contagem de Plaquetas , Curva ROC
12.
Gene ; 893: 147961, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37931853

RESUMO

BACKGROUND: Lupus nephritis (LN) is a common immune disease. The microRNA (miR)-181d-5p is a potential target for treating kidney injury. However, the therapeutic role of miR-181d-5p in LN has not been investigated. This study aimed to investigate the role of miR-181d-5p in targeting mitogen-activated protein kinase 8 (MAPK8) and stimulating the MAPK signaling pathway in LN. METHODS: RT-qPCR was performed to identify the variations in miR-181d-5p expression in peripheral blood mononuclear cells (PBMCs) obtained from 42 LN patients, 30 healthy individuals, 6 MRL/lpr mice and 6 C57BL/6 mice. Western blot was used to detect the effect of miR-181d-5p on the MAPK signaling pathway in THP-1 cells and MRL/lpr mice. Enzyme-linked immunosorbent assay (ELISA) was utilized to detect the effect of miR-181d-5p on antinuclear antibodies and inflammatory factors. A dual-luciferase reporter assay was used to verify whether miR-181d-5p directly targets MAPK8. Flow cytometry was performed to evaluate apoptosis rates in transfected THP-1 cells. RESULTS: miR-181d-5p expression was downregulated in PBMCs of LN patients (P < 0.01) and MRL/lpr mice (P < 0.05). A dual luciferase reporter assay demonstrated that miR-181d-5p inhibits MAPK8 (P < 0.01). Overexpression of miR-181d-5p inhibited the phosphorylation of p38 (P < 0.001) and p44/42 (P < 0.01). Moreover, miR-181d-5p decreased the apoptosis rate of THP-1 cells (P < 0.001), and reduced the secretion of IL-6 (P < 0.01) and TNF-α (P < 0.01). Furthermore, overexpression of miR-181d-5p decreased anti-dsDNA antibody (P < 0.05), anti-Sm antibody (P < 0.01), and fibrosis levels in MRL/lpr mice. CONCLUSION: Upregulation of miR-181d-5p showed anti-inflammatory and anti-apoptotic effects on THP-1 cells in vitro and kidney injury in vivo. These effects were achieved by miR-181d-5p targeting MAPK8 to inhibit phosphorylation of p38 and p44/42. These results may offer new insights for improving therapeutic strategies against lupus nephritis.


Assuntos
Nefrite Lúpica , MicroRNAs , Camundongos , Animais , Humanos , Nefrite Lúpica/genética , Nefrite Lúpica/metabolismo , Proteína Quinase 8 Ativada por Mitógeno , MicroRNAs/metabolismo , Leucócitos Mononucleares/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos MRL lpr , Transdução de Sinais , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Luciferases/metabolismo
13.
RNA ; 17(4): 603-12, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21321186

RESUMO

Delivering small interfering RNA (siRNA) to tumors is the major technical hurdle that prevents the advancement of siRNA-based cancer therapy. One of the difficulties associated with the development of clinically relevant delivery systems is the lack of reliable tools for monitoring siRNA delivery to tumors in vivo. We describe here a novel, positive-readout system where siRNA-mediated target knockdown elicits a rapid and robust increase of reporter activity. Using the positive-readout system, we created (1) ß-galactosidase-based tumor models that allow the detection of target knockdown in 1%-2% of tumor cells and can distinguish between tumor areas where effective target knockdown occurs versus tumor areas that are not accessible to delivery, and (2) luciferase-based tumor models that allow the quantitative assessment of a large number of delivery systems. Using these positive-readout models, we screened a number of literature-described siRNA delivery systems and identified lipid nanoparticles as a promising delivery platform for siRNA-based cancer therapy.


Assuntos
Técnicas de Silenciamento de Genes , Monitorização Fisiológica/métodos , Neoplasias/terapia , RNA Interferente Pequeno/administração & dosagem , Animais , Sequência de Bases , Linhagem Celular Tumoral , Feminino , Genes Reporter , Vetores Genéticos , Lipossomos , Camundongos , Camundongos SCID , Dados de Sequência Molecular , Nanopartículas/administração & dosagem , RNA Interferente Pequeno/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , beta-Galactosidase/genética
14.
Lipids Health Dis ; 12: 11, 2013 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-23388073

RESUMO

BACKGROUND: Peroxisome proliferator activated receptor alpha (PPARα) ameliorates ethanol induced hepatic steatohepatitis. However, its role in alcoholic liver fibrosis has not been fully clarified. The aim of this study was to elucidate the effect and the molecular basis of PPARα in ethanol induced liver fibrosis in mice. METHODS: C57BL/6J mice were fed with 4% ethanol-containing Lieber-DeCarli liquid diet for eight weeks, and intraperitoneal injected with 5% carbon tetrachloride (CCl4) for the last four weeks to induce alcoholic liver fibrosis. PPARα agonist WY14643 was administered to mice during the last couple of weeks. The effects of PPARα induction on liver histology, activation of hepatic stellate cells (HSCs), as well as hepatic expression of inflammatory and fibrogenic factors were assessed. RESULTS: The ethanol plus CCl4 treated mice exhibited progressive liver injury including piecemeal necrosis of hepatocytes, severe inflammatory cells infiltration and bridging fibrosis. This was accompanied by down-regulated hepatic expression of PPARα and the protective cytokines adiponectin, heme oxygenase-1 and interleukin-10. Additionally, up-regulation of the proinflammatory cytokine tumor necrosis factor-alpha, as well as the profibrogenic genes osteopontin, transforming growth factor-beta 1, visfatin, phosphatidylinositol 3-kinase, matrix metalloproteinase-2 (MMP-2) and MMP-9 was observed. WY14643 treatment restored expression of cytokines altered by ethanol plus CCl4 treatment and concomitantly ameliorated the liver injury. CONCLUSIONS: The present study provides evidence for the protective role of PPARα induction in ameliorating ethanol mediated fibrosis through mediation of inflammatory and fibrogenic factors.


Assuntos
Anticolesterolemiantes/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Cirrose Hepática/tratamento farmacológico , PPAR alfa/genética , Pirimidinas/farmacologia , Adiponectina/genética , Adiponectina/metabolismo , Animais , Tetracloreto de Carbono , Citocinas/genética , Citocinas/metabolismo , Etanol , Regulação da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Interleucina-10/genética , Interleucina-10/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Nicotinamida Fosforribosiltransferase/genética , Nicotinamida Fosforribosiltransferase/metabolismo , Osteopontina/genética , Osteopontina/metabolismo , PPAR alfa/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
15.
Zhonghua Gan Zang Bing Za Zhi ; 21(2): 129-33, 2013 Feb.
Artigo em Zh | MEDLINE | ID: mdl-23663886

RESUMO

OBJECTIVE: To explore the role and mechanism of the Fas/Fas ligand (FasL) system and its downstream signaling pathway related to the progression of alcoholic steatohepatitis and liver fibrosis. METHODS: Eighteen C57BL/6J mice were randomly divided into three groups: controls; alcoholic steatohepatitis model, given four-weeks of a 4% ethanol-containing Lieber-DeCarli liquid diet; alcoholic steatohepatitis and liver fibrosis model, given the four-week alcohol diet followed by twice weekly intraperitoneal injections of carbon tetrachloride (5% olive oil solution; 2 mL/kg dose) during the fifth to eighth weeks. Mice in the model groups were sacrificed at the end of week 4 and 8, respectively, along with control mice for comparative analyses. Liver tissue sections were evaluated for hepatocellular apoptosis by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay. The mRNA expression of Fas, FasL, cysteine aspartate-specific proteases 3 (caspase 3), and cytochrome P450 2E1 (CYP 2E1) in liver tissues was detected by reverse transcription (RT)-PCR, visualized by ethidium bromide staining, and normalized to the gray-value of GAPDH expression. The protein expression of Fas and caspase 3 were detected by western blotting (b-actin normalized), and of FasL and CYP 2E1 by immunohistochemistry staining. Intergroup differences and statistical significance were evaluated by single factor analysis of variance and the least squares difference-t test or the Kruskal-Wallis H test and the Mann-Whitney U test. RESULTS: The number of apoptotic cells in the liver sections was significantly higher in both model groups with alcoholic steatohepatitis (vs. controls) and the amount in the alcoholic steatohepatitis plus liver fibrosis model was significantly higher than that in the model with only alcoholic steatohepatitis. In addition, activation of Fas, FasL and its downstream signaling pathway showed an increasing trend with extent of liver injury. The hepatic mRNA (by RT-PCR) and protein (by western blotting) normalized expression levels in the controls, alcoholic steatohepatitis models, and alcoholic steatohepatitis plus liver fibrosis models were, respectively: Fas mRNA: 0.50+/-0.05, 0.61+/-0.10, 0.76+/-0.03 (H=12.137, P less than 0.05), protein: 0.52+/-0.14, 0.86+/-0.10, 0.99+/-0.09 (F=12.758, P less than 0.01); FasL mRNA: 0.31+/-0.03, 0.53+/-0.02, 1.02+/-0.04 (F=153.260, P less than 0.01); caspase 3 mRNA: 0.86+/-0.11, 0.85+/-0.05, 1.33+/-0.16 (F=8.740, P less than 0.01), protein: 0.40+/-0.03, 0.69+/-0.06, 1.02+/-0.10 (F=90.785, P less than 0.01); CYP 2E1 mRNA: 0.72+/-0.14, 1.00+/-0.15, 1.30+/-0.20 (H=4.713, P less than 0.01). The changes in hepatic FasL and CYP 2E1 expression detected by immunohistochemistry were consistent with the mRNA expression. CONCLUSION: Activation of Fas/FasL and its downstream signaling pathway, which induces hepatocellular apoptosis, contributes to the development of alcoholic steatohepatitis and liver fibrosis.


Assuntos
Proteína Ligante Fas/metabolismo , Fígado Gorduroso Alcoólico/metabolismo , Cirrose Hepática/metabolismo , Transdução de Sinais , Receptor fas/metabolismo , Animais , Apoptose , Citocromo P-450 CYP2E1/metabolismo , Fígado Gorduroso Alcoólico/patologia , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
16.
Micromachines (Basel) ; 14(11)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-38004902

RESUMO

At present, a large number of two-degree-of-freedom piezoelectrically driven compliant mechanisms (2-DOF PDCMs) have been widely adopted to construct various elliptical vibration machining (EVM) devices employed in precisely fabricating functional micro-structured surfaces on difficult-to-cut materials, which have broad applications in many significant fields like optical engineering and precision manufacturing. For a higher precision of conventional 2-DOF PDCMs on tracking elliptical trajectories, a novel type of pseudo-decoupling method is proposed based on phase difference compensation (PDC). With finite element analysis (FEA), the dependences of elliptical trajectory tracking precision on PDC angles will then be investigated for optimizing PDC angles under different elliptical parameters. As the modification of the PDC-based method, another type of pseudo-decoupling method will be improved based on elliptical parameter compensation (EPC) for much higher tracking precision, an amplification coefficient and a coupling coefficient will be introduced to mathematically construct the EPC-based model. A series of FEA simulations will also be conducted on a conventional 2-DOF PDCM to calculate the amplification and coupling coefficients as well as optimize the EPC parameters under four series of elliptical parameters. The tracking precision and operational feasibility of these two new pseudo-decoupling methods on four series of elliptical trajectories will be further analyzed and discussed in detail. Meanwhile, a conventional 2-DOF PDCM will be practically adopted to build an experimental system for investigating the pseudo-decoupling performances of an EPC-based method, the input and output displacements will be measured and collected to actually calculate the amplification coefficients and coupling coefficients, further inversely solving the actual input elliptical parameters with EPC. The error distances between the expected and experimental elliptical trajectories will also be calculated and discussed. Finally, several critical conclusions on this study will be briefly summarized.

17.
ACS Appl Mater Interfaces ; 15(36): 43016-43025, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37651194

RESUMO

In this study, different flexible structures that are morphologically like the micro-nano pillars, setae, and cilia on many natural organism surfaces are created with a novel fabricating strategy to explore the phenomenon and mechanism of static and dynamic droplets forming on them. Just by adjusting the mold pattern during fabrication, different micro/nanomorphologies including micro-nano pillar, filament, or flake arrays could be conveniently obtained on a pristine smooth film surface. Due to the existence of uniformly distributed hierarchical micro-nano structure arrays that are composed of top-down nanoscale filamentous tips, micro block bases, and grooves on the film, air trapped in arrays connects the atmosphere continuously and forms a successive air-pocket layer, which greatly reduces the solid-liquid interfacial fraction and endows the micro-nanotextured film with the capability of superhydrophobicity, low-adhesion, self-cleaning, anti-icing, and deicing characteristics. Through various mechanical and chemical tests, the film has demonstrated its robustness, making it highly suitable for a wide range of practical engineering applications.

18.
Lipids Health Dis ; 11: 45, 2012 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-22452814

RESUMO

BACKGROUND: Fuzheng Huayu recipe (FZHY), a compound of Chinese herbal medicine, was reported to improve liver function and fibrosis in patients with hepatitis B virus infection. However, its effect on nutritional fibrosing steatohepatitis is unclear. We aimed to elucidate the role and molecular mechanism of FZHY on this disorder in mice. METHODS: C57BL/6 J mice were fed with methionine-choline deficient (MCD) diet for 8 weeks to induce fibrosing steatohepatitis. FZHY and/or heme oxygenase-1 (HO-1) chemical inducer (hemin) were administered to mice, respectively. The effect of FZHY was assessed by comparing the severity of hepatic injury, levels of hepatic lipid peroxides, activation of hepatic stellate cells (HSCs) and the expression of oxidative stress, inflammatory and fibrogenic related genes. RESULTS: Mice fed with MCD diet for 8 weeks showed severe hepatic injury including hepatic steatosis, necro-inflammation and fibrosis. Administration of FZHY or hemin significantly lowered serum levels of alanine aminotransferase, aspartate aminotransferase, reduced hepatic oxidative stress and ameliorated hepatic inflammation and fibrosis. An additive effect was observed in mice fed MCD supplemented with FZHY or/and hemin. These effects were associated with down-regulation of pro-oxidative stress gene cytochrome P450 2E1, up-regulation of anti-oxidative gene HO-1; suppression of pro-inflammation genes tumor necrosis factor alpha and interleukin-6; and inhibition of pro-fibrotic genes including α-smooth muscle actin, transforming growth factor beta 1, collagen type I (Col-1) and Col-3. CONCLUSIONS: Our study demonstrated the protective role of FZHY in ameliorating nutritional fibrosing steatohepatitis. The effect was mediated through regulating key genes related to oxidative stress, inflammation and fibrogenesis.


Assuntos
Antioxidantes/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Fígado Gorduroso/prevenção & controle , Fígado/efeitos dos fármacos , Actinas/genética , Actinas/metabolismo , Animais , Citocromo P-450 CYP2E1/genética , Citocromo P-450 CYP2E1/metabolismo , Citocinas/genética , Citocinas/metabolismo , Dieta/efeitos adversos , Quimioterapia Combinada , Inibidores Enzimáticos/uso terapêutico , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Fibrose , Regulação da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/antagonistas & inibidores , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Hemina/uso terapêutico , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Fígado/metabolismo , Fígado/patologia , Fígado/fisiopatologia , Masculino , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Necrose , RNA Mensageiro/metabolismo , Distribuição Aleatória
19.
Int J Mol Med ; 49(4)2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35137921

RESUMO

The aim of the present study was to elucidate the effect of resveratrol on non­alcoholic steatohepatitis (NASH), and the molecular basis in mice and Hepa1­6 cells, in order to verify its therapeutic effect. C57BL/6J mice were fed a methionine­choline­deficient (MCD) diet to induce steatohepatitis and were treated with resveratrol. Mouse sera were collected for biochemical analysis and enzyme­linked immunosorbent assay, and livers were obtained for histological observation, and mmu­microRNA (miR)­599 and inflammation­related gene expression analysis. Hepa1­6 cells were treated with palmitic acid to establish a NASH cell model, and were then treated with resveratrol, or transfected with mmu­miR­599 mimic, mmu­miR­599 inhibitor or recombinant pregnane X receptor (PXR) plasmid. Subsequently, the cells were collected for mmu­miR­599 and inflammation­related gene expression analysis. Reverse transcription­quantitative polymerase chain reaction and western blotting were used to assess mmu­miR­599 expression levels, and the mRNA and protein expression levels of PXR and inflammation­related genes. The binding site of mmu­miR­599 in the PXR mRNA was verified by the luciferase activity assay. Mice fed an MCD diet for 4 weeks exhibited steatosis, focal necrosis and inflammatory infiltration in the liver. Resveratrol significantly reduced serum aminotransferase and malondialdehyde levels, and ameliorated hepatic injury. These effects were associated with reduced mmu­miR­599 expression, enhanced PXR expression, and downregulated levels of nuclear factor­κB, tumour necrosis factor­α, interleukin (IL)­1ß, IL­6, NOD­like receptor family pyrin domain­containing protein 3 and signal transducer and activator of transcription 3. Administration of the mmu­miR­599 mimic inhibited PXR expression in Hepa1­6 cells, whereas the mmu­miR­599 inhibitor exerted the opposite effect. A binding site for mmu­miR­599 was identified in the PXR mRNA sequence. Furthermore, overexpression of PXR inhibited the expression of inflammatory factors in Hepa1­6 cells. The present study provided evidence for the protective role of resveratrol in ameliorating steatohepatitis through regulating the mmu­miR­599/PXR pathway and the consequent suppression of related inflammatory factors. Resveratrol may serve as a potential candidate for steatohepatitis management.


Assuntos
MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Animais , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Receptor de Pregnano X/metabolismo , Resveratrol/farmacologia , Resveratrol/uso terapêutico
20.
Scand J Gastroenterol ; 46(3): 358-69, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20969493

RESUMO

OBJECTIVE: The pathogenesis of non-alcoholic steatohepatitis is still unclear. We have demonstrated previously that peroxisome proliferator activated receptor gamma (PPARγ) ligand protects against inflammation and fibrogenesis in experimental non-alcoholic steatohepatitis. We aim to elucidate the effect and the mechanism of PPARγ itself on nutritional fibrotic steatohepatitis in mice. METHODS: C57BL/6J mice were fed with methionine-choline deficient (MCD) diet for 8 weeks to induce fibrotic steatohepatitis. Mice fed the MCD diet were treated with adenovirus carrying PPARγ (Ad-PPARγ), Ad-PPARγ plus PPARγ agonist rosiglitazone, or PPARγ antagonist 2-chloro-5-nitrobenzaniliden (GW9662), respectively. The effects of up-regulation of PPARγ in the presence or absence of its agonist/or antagonist were assessed by comparing the severity of hepatic injury, activation of hepatic stellate cells and the expression of adiponectin, heme oxygenase-1, and fibrogenic related genes. RESULTS: Mice fed with MCD diet for 8 weeks showed severe hepatic injury including hepatic steatosis, inflammatory infiltration, and fibrosis. Administration of Ad-PPARγ significantly lowered serum alanine aminotransferase level and ameliorated hepatic steatosis, necroinflammation, and fibrosis. These effects were associated with enhanced expression of PPARγ, up-regulated expression of adiponectin and heme oxygenase-1, and down-regulated expression of tumor necrosis factor alpha, interleukin-6, α-smooth muscle actin, transforming growth factor beta 1, matrix metallopeptidase-2, and -9. Administration of GW9662 promoted the severity of liver histology. CONCLUSIONS: The present study provided evidences for the protective role of overexpressing PPARγ in ameliorating hepatic fibrosing steatohepatitis in mice. Modulation of PPARγ expression might serve as a therapeutic approach for fibrotic steatohepatitis.


Assuntos
Fígado Gorduroso/prevenção & controle , Vetores Genéticos/administração & dosagem , PPAR gama/biossíntese , PPAR gama/uso terapêutico , Adenoviridae/genética , Anilidas/administração & dosagem , Animais , Colina , Dieta , Fígado Gorduroso/etiologia , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Inflamação/genética , Inflamação/fisiopatologia , Cirrose Hepática/etiologia , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Cirrose Hepática/prevenção & controle , Cirrose Hepática Experimental , Masculino , Metionina/deficiência , Camundongos , Camundongos Endogâmicos C57BL , PPAR gama/administração & dosagem , PPAR gama/genética , Distribuição Aleatória , Rosiglitazona , Tiazolidinedionas/administração & dosagem , Transfecção , beta-Galactosidase/administração & dosagem , beta-Galactosidase/genética
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