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1.
Int J Mol Sci ; 22(5)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802299

RESUMO

Selenium is an essential micronutrient with a wide range of biological effects in mammals. The inorganic form of selenium, selenite, is supplemented to relieve individuals with selenium deficiency and to alleviate associated symptoms. Additionally, physiological and supranutritional selenite have shown selectively higher affinity and toxicity towards cancer cells, highlighting their potential to serve as chemotherapeutic agents or adjuvants. At varying doses, selenite extensively regulates cellular signaling and modulates many cellular processes. In this study, we report the identification of Delta-Notch signaling as a previously uncharacterized selenite inhibited target. Our transcriptomic results in selenite treated primary mouse hepatocytes revealed that the transcription of Notch1, Notch2, Hes1, Maml1, Furin and c-Myc were all decreased following selenite treatment. We further showed that selenite can inhibit Notch1 expression in cultured MCF7 breast adenocarcinoma cells and HEPG2 liver carcinoma cells. In mice acutely treated with 2.5 mg/kg selenite via intraperitoneal injection, we found that Notch1 expression was drastically lowered in liver and kidney tissues by 90% and 70%, respectively. Combined, these results support selenite as a novel inhibitor of Notch signaling, and a plausible mechanism of inhibition has been proposed. This discovery highlights the potential value of selenite applied in a pathological context where Notch is a key drug target in diseases such as cancer, fibrosis, and neurodegenerative disorders.


Assuntos
Receptores Notch/metabolismo , Ácido Selenioso/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Feminino , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Células MCF-7 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Selênio/metabolismo , Transcriptoma/efeitos dos fármacos
2.
Int J Mol Sci ; 22(5)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802460

RESUMO

The lysosomal storage disease Niemann-Pick type C (NPC) is caused by impaired cholesterol efflux from lysosomes, which is accompanied by secondary lysosomal accumulation of sphingomyelin and glucosylceramide (GlcCer). Similar to Gaucher disease (GD), patients deficient in glucocerebrosidase (GCase) degrading GlcCer, NPC patients show an elevated glucosylsphingosine and glucosylated cholesterol. In livers of mice lacking the lysosomal cholesterol efflux transporter NPC1, we investigated the expression of established biomarkers of lipid-laden macrophages of GD patients, their GCase status, and content on the cytosol facing glucosylceramidase GBA2 and lysosomal integral membrane protein type B (LIMP2), a transporter of newly formed GCase to lysosomes. Livers of 80-week-old Npc1-/- mice showed a partially reduced GCase protein and enzymatic activity. In contrast, GBA2 levels tended to be reciprocally increased with the GCase deficiency. In Npc1-/- liver, increased expression of lysosomal enzymes (cathepsin D, acid ceramidase) was observed as well as increased markers of lipid-stressed macrophages (GPNMB and galectin-3). Immunohistochemistry showed that the latter markers are expressed by lipid laden Kupffer cells. Earlier reported increase of LIMP2 in Npc1-/- liver was confirmed. Unexpectedly, immunohistochemistry showed that LIMP2 is particularly overexpressed in the hepatocytes of the Npc1-/- liver. LIMP2 in these hepatocytes seems not to only localize to (endo)lysosomes. The recent recognition that LIMP2 harbors a cholesterol channel prompts the speculation that LIMP2 in Npc1-/- hepatocytes might mediate export of cholesterol into the bile and thus protects the hepatocytes.


Assuntos
Glucosilceramidase/metabolismo , Fígado/metabolismo , Glicoproteínas de Membrana Associadas ao Lisossomo/metabolismo , Doença de Niemann-Pick Tipo C/metabolismo , Receptores Depuradores/metabolismo , Animais , Transporte Biológico/fisiologia , Catepsina D/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Doença de Gaucher/metabolismo , Glucosilceramidas/metabolismo , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Lisossomos/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Células RAW 264.7 , Esfingomielinas/metabolismo
3.
Int J Mol Sci ; 22(6)2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33803025

RESUMO

The liver mass constitutes hepatocytes expressing receptors for vitamin B12 (B12)-bound transporters in circulation. However, intrahepatic and circulating B12 interrelationship levels remain unclear. We assessed the intracellular B12 levels at various circulating B12 concentrations in human HepG2 cell-line and liver tissue levels of B12 in the C57BL/6 mouse model. In HepG2 cells treated with a range of B12 concentrations, the intracellular and circulatory B12 levels, transcript and protein levels of B12 receptor (CD320) and transporter (TCN2) were determined using immunoassays, qRT-PCR and Western blot, respectively. Similar assessments were done in plasma and liver tissue of C57BL/6 mice, previously fed a diet of either a high or low B12 (30.82 µg B12/kg and 7.49 µg B12/kg, respectively) for 8-10 weeks. The physiological B12 status (0.15-1 nM) resulted in increased levels of intracellular B12 in HepG2 cells compared to supraphysiological levels of B12 (>1 nM). Gene and protein expression of CD320 and TCN2 were also higher at physiological levels of B12. Progressively increasing extracellular B12 to supraphysiological levels led to relative decreased levels of intracellular B12, lower expression of gene and protein levels of CD320 and TCN2. Similar results were observed in liver tissue from mice fed on a low B12 diet verses high B12 diet. These findings suggest that unlike supraphysiological B12, physiological levels of B12 in the extracellular media or circulation accelerates active transport of B12, and expression of CD320 and TCN2, resulting in higher relative uptake of B12 in hepatocytes.


Assuntos
Antígenos CD/metabolismo , Hepatócitos/metabolismo , Espaço Intracelular/metabolismo , Fígado/metabolismo , Receptores de Superfície Celular/metabolismo , Transcobalaminas/metabolismo , Vitamina B 12/metabolismo , Animais , Antígenos CD/genética , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Superfície Celular/genética , Transcobalaminas/genética
4.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807969

RESUMO

Sitosterolemia is a lipid disorder characterized by the accumulation of dietary xenosterols in plasma and tissues caused by mutations in either ABCG5 or ABCG8. ABCG5 ABCG8 encodes a pair of ABC half transporters that form a heterodimer (G5G8), which then traffics to the surface of hepatocytes and enterocytes and promotes the secretion of cholesterol and xenosterols into the bile and the intestinal lumen. We review the literature from the initial description of the disease, the discovery of its genetic basis, current therapy, and what has been learned from animal, cellular, and molecular investigations of the transporter in the twenty years since its discovery. The genomic era has revealed that there are far more carriers of loss of function mutations and likely pathogenic variants of ABCG5 ABCG8 than previously thought. The impact of these variants on G5G8 structure and activity are largely unknown. We propose a classification system for ABCG5 ABCG8 mutants based on previously published systems for diseases caused by defects in ABC transporters. This system establishes a framework for the comprehensive analysis of disease-associated variants and their impact on G5G8 structure-function.


Assuntos
Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Colesterol/metabolismo , Hipercolesterolemia , Enteropatias , Erros Inatos do Metabolismo Lipídico , Lipoproteínas , Mutação , Fitosteróis/efeitos adversos , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/história , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/história , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Enterócitos/metabolismo , Enterócitos/patologia , Hepatócitos/metabolismo , Hepatócitos/patologia , História do Século XXI , Humanos , Hipercolesterolemia/genética , Hipercolesterolemia/história , Hipercolesterolemia/metabolismo , Hipercolesterolemia/patologia , Enteropatias/genética , Enteropatias/história , Enteropatias/metabolismo , Enteropatias/patologia , Erros Inatos do Metabolismo Lipídico/genética , Erros Inatos do Metabolismo Lipídico/história , Erros Inatos do Metabolismo Lipídico/metabolismo , Erros Inatos do Metabolismo Lipídico/patologia , Lipoproteínas/genética , Lipoproteínas/história , Lipoproteínas/metabolismo , Fitosteróis/genética , Fitosteróis/história , Fitosteróis/metabolismo
5.
Int J Mol Sci ; 22(6)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805784

RESUMO

Hepatocellular carcinoma (HCC) frequently shows early invasion into blood vessels as well as intrahepatic metastasis. Innovations of novel small-molecule agents to block HCC invasion and subsequent metastasis are urgently needed. Moscatilin is a bibenzyl derivative extracted from the stems of a traditional Chinese medicine, orchid Dendrobium loddigesii. Although moscatilin has been reported to suppress tumor angiogenesis and growth, the anti-metastatic property of moscatilin has not been elucidated. The present results revealed that moscatilin inhibited metastatic behavior of HCC cells without cytotoxic fashion in highly invasive human HCC cell lines. Furthermore, moscatilin significantly suppressed the activity of urokinase plasminogen activator (uPA), but not matrix metalloproteinase (MMP)-2 and MMP-9. Interestingly, moscatilin-suppressed uPA activity was through down-regulation the protein level of uPA, and did not impair the uPA receptor and uPA inhibitory molecule (PAI-1) expressions. Meanwhile, the mRNA expression of uPA was inhibited via moscatilin in a concentration-dependent manner. In addition, the expression of phosphorylated Akt, rather than ERK1/2, was inhibited by moscatilin treatment. The expression of phosphor-IκBα, and -p65, as well as κB-luciferase activity were also repressed after moscatilin treatment. Transfection of constitutively active Akt (Myr-Akt) obviously restored the moscatilin-inhibited the activation of NF-κB and uPA, and cancer invasion in HCC cells. Taken together, these results suggest that moscatilin impedes HCC invasion and uPA expression through the Akt/NF-κB signaling pathway. Moscatilin might serve as a potential anti-metastatic agent against the disease progression of human HCC.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Compostos de Benzil/farmacologia , Movimento Celular/efeitos dos fármacos , NF-kappa B/genética , Proteínas Proto-Oncogênicas c-akt/genética , Ativador de Plasminogênio Tipo Uroquinase/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Embrião de Galinha , Membrana Corioalantoide/irrigação sanguínea , Membrana Corioalantoide/efeitos dos fármacos , Fator de Iniciação 4E em Eucariotos/genética , Fator de Iniciação 4E em Eucariotos/metabolismo , Regulação Neoplásica da Expressão Gênica , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/prevenção & controle , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/genética , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/antagonistas & inibidores , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
6.
Int J Mol Sci ; 22(5)2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33800828

RESUMO

Hypercholesterolemia is one of the major causes of cardiovascular disease, the risk of which is further increased if other forms of dyslipidemia occur. Current therapeutic strategies include changes in lifestyle coupled with drug administration. Statins represent the most common therapeutic approach, but they may be insufficient due to the onset of resistance mechanisms and side effects. Consequently, patients with mild hypercholesterolemia prefer the use of food supplements since these are perceived to be safer. Here, we investigate the phytochemical profile and cholesterol-lowering potential of Protium heptaphyllum gum resin extract (PHE). Chemical characterization via HPLC-APCI-HRMS2 and GC-FID/MS identified 13 compounds mainly belonging to ursane, oleanane, and tirucallane groups. Studies on human hepatocytes have revealed how PHE is able to reduce cholesterol production and regulate the expression of proteins involved in its metabolism. (HMGCR, PCSK9, LDLR, FXR, IDOL, and PPAR). Moreover, measuring the inhibitory activity of PHE against HMGR, moderate inhibition was recorded. Finally, molecular docking studies identified acidic tetra- and pentacyclic triterpenoids as the main compounds responsible for this action. In conclusion, our study demonstrates how PHE may be a useful alternative to contrast hypercholesterolemia, highlighting its potential as a sustainable multitarget natural extract for the nutraceutical industry that is rapidly gaining acceptance as a source of health-promoting compounds.


Assuntos
Anticolesterolemiantes/farmacologia , Hidrogênio/química , Gomas Vegetais/química , Resinas Vegetais/química , Triterpenos/farmacologia , Anticolesterolemiantes/isolamento & purificação , Domínio Catalítico/efeitos dos fármacos , Colesterol/metabolismo , Cromatografia Líquida de Alta Pressão , Suplementos Nutricionais , Avaliação Pré-Clínica de Medicamentos , Ionização de Chama , Cromatografia Gasosa-Espectrometria de Massas , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Lovastatina/farmacologia , Modelos Moleculares , Simulação de Acoplamento Molecular , Conformação Proteica , Triterpenos/isolamento & purificação
7.
Zhonghua Gan Zang Bing Za Zhi ; 29(3): 271-274, 2021 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-33902196

RESUMO

To construct cellular senescence model by stimulating primary hepatocytes with hydrogen peroxide (H(2)O(2)). Primary hepatocytes were transfected with p53 siRNA, progerin siRNA or IGF-1 adenovirus vector. The number of SA-ß-Gal stained positive cells and the expression of p53 and progerin were detected. The results showed that p53 siRNA and progerin siRNA had knocked-down the expression of p53 and progerin, and had alleviated the hepatocyte senescence. Transfection of insulin-like growth factor (IGF)-1 adenovirus vector into primary hepatocytes had overexpressed IGF-1, and had alleviated the number of SA-ß-Gal-positive cells. The expression of p53 and progerin was down-regulated in the nucleus, while the expression of p53 was up-regulated in the cytoplasm. The co-precipitation and co-localization of p53 and progerin was decreased in the nuclear region of hepatocytes. IGF-1 overexpression can inhibit intranuclear p53 translocation, alleviate the interaction between p53-progerin, and alleviate hepatocyte senescence.


Assuntos
Fator de Crescimento Insulin-Like I , Proteína Supressora de Tumor p53 , Senescência Celular , Hepatócitos , Peróxido de Hidrogênio , Proteína Supressora de Tumor p53/genética
8.
Int J Mol Sci ; 22(6)2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33804769

RESUMO

SARS-CoV-2 infection can cause cytokine storm and may overshoot immunity in humans; however, it remains to be determined whether virus-induced soluble mediators from infected cells are carried by exosomes as vehicles to distant organs and cause tissue damage in COVID-19 patients. We took an unbiased proteomic approach for analyses of exosomes isolated from plasma of healthy volunteers and COVID-19 patients. Our results revealed that tenascin-C (TNC) and fibrinogen-ß (FGB) are highly abundant in exosomes from COVID-19 patients' plasma compared with that of healthy normal controls. Since TNC and FGB stimulate pro-inflammatory cytokines via the Nuclear factor-κB (NF-κB) pathway, we examined the status of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and C-C motif chemokine ligand 5 (CCL5) expression upon exposure of hepatocytes to exosomes from COVID-19 patients and observed significant increase compared with that from healthy subjects. Together, our results demonstrate that TNC and FGB are transported through plasma exosomes and potentially trigger pro-inflammatory cytokine signaling in cells of distant organ.


Assuntos
/sangue , Exossomos/química , Exossomos/genética , Fibrinogênio/metabolismo , Inflamação/metabolismo , Tenascina/metabolismo , Idoso , Linhagem Celular , Quimiocina CCL5/metabolismo , Exossomos/metabolismo , Exossomos/ultraestrutura , Feminino , Hepatócitos/metabolismo , Humanos , Inflamação/etiologia , Interleucina-6/metabolismo , Masculino , Espectrometria de Massas , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Mapas de Interação de Proteínas , Proteoma/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
9.
Acta Virol ; 65(1): 82-88, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33827225

RESUMO

Hepatitis B virus (HBV) is a partially double-stranded DNA virus that specifically targets hepatocytes. It is considered a major health issue due to its high prevalence and the life-threatening consequences of chronic infection, including liver cirrhosis and hepatocellular carcinoma. Despite widespread vaccination against HBV, millions of people live with chronic HBV infection. Existing antiviral therapies fail to achieve full HBV elimination, so most patients with the disease require lifelong treatment. The search for new antiviral therapy strategies is hindered by the limited availability of in vitro HBV infection models that are able to support the full HBV life cycle. Therefore, the development and optimization of cellular models are crucial to the search for drugs effective against HBV. In this study, we optimized an in vitro HBV infection model consisting of two cell lines: HepAD38 cells, which are able to produce infectious HBV; and HepG2-NTCP cells, which are susceptible to HBV infection. We showed that prolonged production of HBV in the "donor" cells and HBV inoculation of the "acceptor" cells simultaneously with seeding improves the established procedure. This modified protocol was proven effective in experiments involving compounds with known activity against HBV, suggesting its utility for future high-throughput screening. Keywords: HBV; HBV in vitro models; HepG2-NTCP; HepAD38.


Assuntos
Hepatite B , Simportadores , Antivirais/farmacologia , Avaliação Pré-Clínica de Medicamentos , Hepatite B/tratamento farmacológico , Vírus da Hepatite B/genética , Hepatócitos , Ensaios de Triagem em Larga Escala , Humanos , Transportadores de Ânions Orgânicos Dependentes de Sódio/farmacologia , Simportadores/farmacologia , Replicação Viral
10.
Int J Mol Sci ; 22(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806448

RESUMO

Lambda interferons mediate antiviral immunity by inducing interferon-stimulated genes (ISGs) in epithelial tissues. A common variant rs368234815TT/∆G creating functional gene from an IFNL4 pseudogene is associated with the expression of major ISGs in the liver but impaired clearance of hepatitis C. To explain this, we compared Halo-tagged and non-tagged IFNL3 and IFNL4 signaling in liver-derived cell lines. Transfection with non-tagged IFNL3, non-tagged IFNL4 and Halo-tagged IFNL4 led to a similar degree of JAK-STAT activation and ISG induction; however, the response to transfection with Halo-tagged IFNL3 was lower and delayed. Transfection with non-tagged IFNL3 or IFNL4 induced no transcriptome change in the cells lacking either IL10R2 or IFNLR1 receptor subunits. Cytosolic overexpression of signal peptide-lacking IFNL3 or IFNL4 in wild type cells did not interfere with JAK-STAT signaling triggered by interferons in the medium. Finally, expression profile changes induced by transfection with non-tagged IFNL3 and IFNL4 were highly similar. These data do not support the hypothesis about IFNL4-specific non-canonical signaling and point out that functional studies conducted with tagged interferons should be interpreted with caution.


Assuntos
Hepatócitos/imunologia , Hepatócitos/metabolismo , Interferons/genética , Interferons/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Linhagem Celular , Expressão Gênica , Técnicas de Inativação de Genes , Células Hep G2 , Humanos , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , Interferons/deficiência , Subunidade beta de Receptor de Interleucina-10/deficiência , Subunidade beta de Receptor de Interleucina-10/genética , Subunidade beta de Receptor de Interleucina-10/metabolismo , Interleucinas/deficiência , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Interferon/deficiência , Receptores de Interferon/genética , Receptores de Interferon/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Transfecção
11.
Chem Biol Interact ; 340: 109448, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33775687

RESUMO

Metabolic deactivation by cytochrome P450 (CYP) is considered a potential mechanism of anticancer drug resistance. However, this hypothesis is predominantly based on indirect pieces of evidence and/or is influenced by interfering factors such as the use of multienzymatic models. Thus, an experimental approach for its verification is needed. In the present work, we employed HepG2 cells transduced with CYP enzymes involved in docetaxel, paclitaxel and vincristine metabolism to provide mechanistic evidence on their possible roles in resistance to these chemotherapeutic agents. Using MTT proliferation tests, we showed that overexpression of CYP3A4 resulted in decreased antiproliferative activity of 1 µM docetaxel (by 11.2, 23.2 and 22.9% at 24, 48 and 72 h intervals, respectively), while the sensitivity of CYP3A4-transduced cells was restored by co-administration of ketoconazole. Paclitaxel exhibited differential efficacy in CYP2C8- and empty vector-transduced cells (significant differences between 10.9 and 24.4% for 0.01, 0.1 and 1 µM concentrations), but neither montelukast nor clotrimazole was capable of affecting this asymmetry. Finally, the pharmacological activity of vincristine was not influenced by CYP3A4 or CYP3A5 overexpression. In the follow-up caspase activation assays, docetaxel was confirmed to be a victim of CYP3A4-mediated resistance, which is, at least partly, brought by impaired activation of caspases 3/7, 8 and 9. In summary, our data demonstrate that CYP3A4-mediated metabolic deactivation of docetaxel might represent a significant mechanism of pharmacokinetic resistance to this drug. In contrast, the possible role of CYPs in resistance to paclitaxel and vincristine has been disconfirmed. Importantly, the expression of CYP3A4 in HepG2_CYP3A4 cells is comparable to that in primary hepatocytes and HepaRG cells, which suggests that our results might be relevant for in vivo conditions, e.g., for hepatocellular carcinoma. Thus, our data may serve as a valuable in vitro background for future in vivo studies exploring the area of intratumoural metabolism-based drug resistance.


Assuntos
Antineoplásicos/farmacologia , Citocromo P-450 CYP2C8/metabolismo , Citocromo P-450 CYP3A/metabolismo , Citostáticos/farmacologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Inativação Metabólica/efeitos dos fármacos , Taxa de Depuração Metabólica/efeitos dos fármacos
12.
Molecules ; 26(5)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673598

RESUMO

Melanin-concentrating hormone (MCH) is a 19 amino acid long peptide found in the brain of animals, including fishes, batrachians, and mammals. MCH is implicated in appetite and/or energy homeostasis. Antagonists at its receptor (MCH-R1) could be major tools (or ultimately drugs) to understand the mechanism of MCH action and to fight the obesity syndrome that is a worldwide societal health problem. Ever since the deorphanisation of the MCH receptor, we cloned, expressed, and characterized the receptor MCH-R1 and started a vast medicinal chemistry program aiming at the discovery of such usable compounds. In the present final work, we describe GPS18169, a pseudopeptide antagonist at the MCH-R1 receptor with an affinity in the nanomolar range and a Ki for its antagonistic effect in the 20 picomolar range. Its metabolic stability is rather ameliorated compared to its initial parent compound, the antagonist S38151. We tested it in an in vivo experiment using high diet mice. GPS18169 was found to be active in limiting the accumulation of adipose tissues and, correlatively, we observed a normalization of the insulin level in the treated animals, while no change in food or water consumption was observed.


Assuntos
Fármacos Antiobesidade/química , Obesidade/tratamento farmacológico , Receptores do Hormônio Hipofisário/antagonistas & inibidores , Tecido Adiposo/efeitos dos fármacos , Alquinos/química , Aminobutiratos/química , Animais , Fármacos Antiobesidade/farmacologia , Apetite/efeitos dos fármacos , Ácido Aspártico/química , Modelos Animais de Doenças , Descoberta de Drogas , Ácido Glutâmico/química , Glicina/análogos & derivados , Glicina/química , Células HEK293 , Hepatócitos/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Humanos , Insulina/metabolismo , Lactamas/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Relação Estrutura-Atividade , Distribuição Tecidual , Triazóis/química
13.
Virus Res ; 297: 198383, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33705798

RESUMO

Slightly acidic hypochlorous acid waters (SAHWs) with pH of 5.2-5.8 containing different concentrations of free available chlorine - 62, 119, 220, 300, and 540 ppm (SAHW-62, -119, -220, -300, and -540, respectively) - were evaluated for their virucidal activity toward a low pathogenic H7N1 avian influenza virus (AIV) and an infectious bronchitis virus (IBV) in suspension, abiotic carrier, and direct spray tests, with the presence of organic materials. In the carrier test, the dropping and wiping techniques were performed toward viruses on carriers. In the suspension test, SAHW-62 could decrease the viral titer of both AIV and IBV by more than 1000 times within 30 s. With the dropping technique, IBV on carriers showed high resistance to SAHW, while AIV on plastic carrier was inactivated to an effective level (≧3 log virus reduction) within 1 min. With the wiping technique, SAHW-62 could inactivate both AIV and IBV on wiped plastic carriers to an effective level within 30 s. However, SAHW-220 could not inactivate IBV in the wiping rayon sheet to an effective level. In the direct spray test, sprayed SAHW-300 within 10 min, and SAHW-540 within 20 min, inactivated AIV and IBV on the rayon sheets to undetectable level, respectively. Our study indicates that the usage of wipes with SAHW could remove viruses from plastic carriers, while viruses remained in the wipes. Besides, a small volume of sprayed SAHW was effective against the viruses on the rayon sheets for daily cleaning in the application area. The findings we obtained concerning IBV might basically be applicable in relation to SARS-CoV-2, given the resemblance between the two viruses.


Assuntos
Antivirais/farmacologia , Desinfetantes/farmacologia , Ácido Hipocloroso/farmacologia , Vírus da Bronquite Infecciosa/efeitos dos fármacos , Vírus da Influenza A Subtipo H7N1/efeitos dos fármacos , Animais , Galinhas , Infecções por Coronavirus/prevenção & controle , Cães , Patos , Hepatócitos , Influenza Aviária/prevenção & controle , Células Madin Darby de Rim Canino
14.
Molecules ; 26(4)2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33672046

RESUMO

Substituted N-phenyl cinnamamide derivatives were designed and synthesized to confirm activation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathway by the electronic effect on beta-position of Michael acceptor according to introducing the R1 and R2 group. Compounds were screened using the Nrf2/antioxidant response element (ARE)-driven luciferase reporter assay. Compound 1g showed desirable luciferase activity in HepG2 cells without cell toxicity. mRNA and protein expression of Nrf2/ARE target genes such as NAD(P)H quinone oxidoreductase 1, hemeoxygenase-1, and glutamate-cysteine ligase catalytic subunit (GCLC) were upregulated by compound 1g in a concentration-dependent manner. Treatment with 1g resulted in increased endogenous antioxidant glutathione, showing strong correlation with enhanced GCLC expression for synthesis of glutathione. In addition, tert-butyl hydroperoxide (t-BHP)-generated reactive oxygen species were significantly removed by 1g, and the results of a cell survival assay in a t-BHP-induced oxidative cell injury model showed a cytoprotective effect of 1g in a concentration dependent manner. In conclusion, the novel compound 1g can be utilized as an Nrf2/ARE activator in antioxidative therapy.


Assuntos
Cinamatos/farmacologia , Citoproteção/efeitos dos fármacos , Glutationa/biossíntese , Hepatócitos/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Elementos de Resposta Antioxidante/genética , Ácidos Carboxílicos/química , Ácidos Carboxílicos/farmacologia , Morte Celular/efeitos dos fármacos , Cinamatos/química , Glutationa/metabolismo , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Humanos , Luciferases/metabolismo , Fator 2 Relacionado a NF-E2/agonistas , Substâncias Protetoras/farmacologia , terc-Butil Hidroperóxido
15.
Int J Mol Sci ; 22(4)2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33669407

RESUMO

La Reunion island in the South West Indian Ocean is now endemic for dengue following the introduction of dengue virus serotype 2 (DENV-2) cosmopolitan-I genotype in 2017. DENV-2 infection causes a wide spectrum of clinical manifestations ranging from flu-like disease to severe dengue. The nonstructural glycoprotein 1 (NS1) has been identified as playing a key role in dengue disease severity. The intracellular NS1 exists as a homodimer, whereas a fraction is driven towards the plasma membrane or released as a soluble hexameric protein. Here, we characterized the NS1 glycoproteins from clinical isolates DES-14 and RUN-18 that were collected during the DENV-2 epidemics in Tanzania in 2014 and La Reunion island in 2018, respectively. In relation to hepatotropism of the DENV, expression of recombinant DES-14 NS1 and RUN-18 NS1 glycoproteins was compared in human hepatoma Huh7 cells. We observed that RUN-18 NS1 was poorly stable in Huh7 cells compared to DES-14 NS1. The instability of RUN-18 NS1 leading to a low level of NS1 secretion mostly relates to lysine residues on positions 272 and 324. Our data raise the issue of the consequences of a defect in NS1 stability in human hepatocytes in relation to the major role of NS1 in the pathogenesis of the DENV-2 infection.


Assuntos
Vírus da Dengue/metabolismo , Dengue/epidemiologia , Dengue/metabolismo , Epidemias , Genótipo , Lisina/química , Proteínas não Estruturais Virais/química , Substituição de Aminoácidos , Antígenos Virais/química , Antígenos Virais/genética , Linhagem Celular Tumoral , Dengue/virologia , Células HEK293 , Hepatócitos/metabolismo , Hepatócitos/virologia , Humanos , Multimerização Proteica , Estabilidade Proteica , Proteínas Recombinantes/química , Reunião/epidemiologia , Sorogrupo , Tanzânia/epidemiologia , Transfecção , Proteínas não Estruturais Virais/genética
16.
Int J Mol Sci ; 22(4)2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33672718

RESUMO

The ATP-binding cassette (ABC) transporters expressed at the canalicular membrane of hepatocytes mediate the secretion of several compounds into the bile canaliculi and therefore play a key role in bile secretion. Among these transporters, ABCB11 secretes bile acids, ABCB4 translocates phosphatidylcholine and ABCG5/G8 is responsible for cholesterol secretion, while ABCB1 and ABCC2 transport a variety of drugs and other compounds. The dysfunction of these transporters leads to severe, rare, evolutionary biliary diseases. The development of new therapies for patients with these diseases requires a deep understanding of the biology of these transporters. In this review, we report the current knowledge regarding the regulation of canalicular ABC transporters' folding, trafficking, membrane stability and function, and we highlight the role of molecular partners in these regulating mechanisms.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Canalículos Biliares/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Endocitose , Glicosilação , Hepatócitos/metabolismo , Humanos , Ubiquitinação
17.
Zhongguo Zhong Yao Za Zhi ; 46(6): 1430-1437, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-33787141

RESUMO

To study phenylpropanoids from Eleocharis dulcis and their hepatoprotective activities. The compounds were separated and purified from ethyl acetate part by conventional column chromatography and preparative liquid chromatography, and their structures were identified by various spectral techniques. The HL-7702 cells damage model of hepatocytes induced by APAP was used to screen and evaluate the hepatoprotective activities of these compounds. Sixteen compounds were isolated from ethyl acetate part of E. dulcis, and their structures were identified as 6'-(4″-hydroxy-3″-methoxy-phenylpropenyl)-1-(10-methoxy-phenylacetone)-1'-O-ß-D-glucopy-ranoside(1), susaroyside A(2), clausenaglycoside B(3), clausenaglycoside C(4), clausenaglycoside D(5), emarginone A(6), emarginone B(7), thoreliin B(8), 4-O-(1',3'-dihydroxypropan-2'-yl)-dihydroconiferyl alcohol 9-O-ß-D-glucopyranoside(9), 2-[4-(3-methoxy-1-propenyl)-2-methoxy-phenoxy]-propane-1,3-diol(10), 6'-O-(E-cinnamoyl)-coniferin(11), methyl 3-(2-O-ß-D-glucopyranosyl-3,4,5,6-tetramethoxyphenyl) propanoate(12), clausenaglycoside A(13), 9-O-(E-cinnamoyl)-coniferin(14), 6'-O-(E-cinnamoyl)-syringin(15), 2'-O-(E-cinnamoyl)-syringin(16). Among them, compound 1 was a new compound. Compounds 2-16 were isolated from this plant for the first time. Among them, compounds 2 and 8 showed certain hepatoprotective activities.


Assuntos
Eleocharis , Cromatografia , Hepatócitos , Extratos Vegetais
18.
Int J Mol Sci ; 22(4)2021 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-33668611

RESUMO

The maintenance of proteome homeostasis, or proteostasis, is crucial for preserving cellular functions and for cellular adaptation to environmental challenges and changes in physiological conditions. The capacity of cells to maintain proteostasis requires precise control and coordination of protein synthesis, folding, conformational maintenance, and clearance. Thus, protein degradation by the ubiquitin-proteasome system (UPS) or the autophagy-lysosomal system plays an essential role in cellular functions. However, failure of the UPS or the autophagic process can lead to the development of various diseases (aging-associated diseases, cancer), thus both these pathways have become attractive targets in the treatment of protein conformational diseases, such as alpha 1-antitrypsin deficiency (AATD). The Z alpha 1-antitrypsin (Z-AAT) misfolded variant of the serine protease alpha 1-antitrypsin (AAT) is caused by a structural change that predisposes it to protein aggregation and dramatic accumulation in the form of inclusion bodies within liver hepatocytes. This can lead to clinically significant liver disease requiring liver transplantation in childhood or adulthood. Treatment of mice with autophagy enhancers was found to reduce hepatic Z-AAT aggregate levels and protect them from AATD hepatotoxicity. To date, liver transplantation is the only curative therapeutic option for patients with AATD-mediated liver disease. Therefore, the development and discovery of new therapeutic approaches to delay or overcome disease progression is a top priority. Herein, we review AATD-mediated liver disease and the overall process of autophagy. We highlight the role of this system in the regulation of Z-variant degradation and its implication in AATD-medicated liver disease, including some open questions that remain challenges in the field and require further elucidation. Finally, we discuss how manipulation of autophagy could provide multiple routes of therapeutic benefit in AATD-mediated liver disease.


Assuntos
Autofagia , Hepatócitos , Hepatopatias , Transplante de Fígado , Fígado , Agregação Patológica de Proteínas , alfa 1-Antitripsina , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Corpos de Inclusão/genética , Corpos de Inclusão/metabolismo , Corpos de Inclusão/patologia , Fígado/metabolismo , Fígado/patologia , Hepatopatias/metabolismo , Hepatopatias/patologia , Hepatopatias/cirurgia , Agregação Patológica de Proteínas/genética , Agregação Patológica de Proteínas/metabolismo , Agregação Patológica de Proteínas/patologia , Agregação Patológica de Proteínas/cirurgia , alfa 1-Antitripsina/genética , alfa 1-Antitripsina/metabolismo , Deficiência de alfa 1-Antitripsina/genética , Deficiência de alfa 1-Antitripsina/metabolismo , Deficiência de alfa 1-Antitripsina/patologia
19.
Methods Mol Biol ; 2269: 151-165, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33687678

RESUMO

Human mesenchymal stromal cells (MSC) are adult stem cells, which feature hepatotropism by supporting liver regeneration through amelioration of hepatic inflammation and lipid accumulation in a mouse model of non-alcoholic steatohepatitis (NASH), a more advanced stage of fatty liver. It remains open, how MSC impact on hepatocytic lipid metabolism. To study MSC actions on fatty liver mechanistically, we established an in vitro model of co-culture comprising MSC and isolated mouse hepatocytes at a ratio of 1:1. Lipid storage in hepatocytes was induced by the treatment with medium deficiency of methionine and choline (MCD). The protocol can be adapted for the use of other lipid storage-inducing agents such as palmitic acid and linoleic acid. This co-culture model allows to study, e.g., whether MSC act indirectly via MSC-born paracrine mechanisms or through direct physical interactions between cells beside others. The protocol allows us to detect the formation of extensions (filopodia) from MSC to contact the fatty hepatocytes or other MSC within 24 h of co-culture. These structures may represent tunneling nanotubes (TNT), allowing for long-range intercellular communication.


Assuntos
Hepatócitos/metabolismo , Fígado/metabolismo , Células-Tronco Mesenquimais/metabolismo , Modelos Biológicos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Comunicação Parácrina , Animais , Técnicas de Cocultura , Hepatócitos/patologia , Humanos , Fígado/patologia , Células-Tronco Mesenquimais/patologia , Camundongos , Hepatopatia Gordurosa não Alcoólica/patologia
20.
Nat Commun ; 12(1): 1658, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712578

RESUMO

Chronic hepatitis B virus (HBV) infection is a major cause of liver disease and cancer worldwide for which there are no curative therapies. The major challenge in curing infection is eradicating or silencing the covalent closed circular DNA (cccDNA) form of the viral genome. The circadian factors BMAL1/CLOCK and REV-ERB are master regulators of the liver transcriptome and yet their role in HBV replication is unknown. We establish a circadian cycling liver cell-model and demonstrate that REV-ERB directly regulates NTCP-dependent hepatitis B and delta virus particle entry. Importantly, we show that pharmacological activation of REV-ERB inhibits HBV infection in vitro and in human liver chimeric mice. We uncover a role for BMAL1 to bind HBV genomes and increase viral promoter activity. Pharmacological inhibition of BMAL1 through REV-ERB ligands reduces pre-genomic RNA and de novo particle secretion. The presence of conserved E-box motifs among members of the Hepadnaviridae family highlight an evolutionarily conserved role for BMAL1 in regulating this family of small DNA viruses.


Assuntos
Relógios Biológicos/fisiologia , Ritmo Circadiano/fisiologia , Vírus da Hepatite B/fisiologia , Replicação Viral/fisiologia , Animais , Relógios Biológicos/efeitos dos fármacos , Relógios Biológicos/genética , Ritmo Circadiano/genética , DNA Circular , DNA Viral/metabolismo , Regulação da Expressão Gênica , Genoma Viral , Células Hep G2 , Hepatite B/virologia , Vírus da Hepatite B/genética , Hepatite B Crônica/genética , Hepatócitos/metabolismo , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Fígado/metabolismo , Camundongos , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , Regiões Promotoras Genéticas , Simportadores/metabolismo , Transcriptoma , Vírion/metabolismo , Internalização do Vírus
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