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1.
Int J Mol Sci ; 24(10)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37240037

RESUMO

Therapy with anti-tumor necrosis factor (TNF) has dramatically changed the natural history of Crohn's disease (CD). However, these drugs are not without adverse events, and up to 40% of patients could lose efficacy in the long term. We aimed to identify reliable markers of response to anti-TNF drugs in patients with CD. A consecutive cohort of 113 anti-TNF naive patients with CD was stratified according to clinical response as short-term remission (STR) or non-STR (NSTR) at 12 weeks of treatment. We compared the protein expression profiles of plasma samples in a subset of patients from both groups prior to anti-TNF therapy by SWATH proteomics. We identified 18 differentially expressed proteins (p ≤ 0.01, fold change ≥ 2.4) involved in the organization of the cytoskeleton and cell junction, hemostasis/platelet function, carbohydrate metabolism, and immune response as candidate biomarkers of STR. Among them, vinculin was one of the most deregulated proteins (p < 0.001), whose differential expression was confirmed by ELISA (p = 0.054). In the multivariate analysis, plasma vinculin levels along with basal CD Activity Index, corticosteroids induction, and bowel resection were factors predicting NSTR.


Assuntos
Antineoplásicos , Doença de Crohn , Humanos , Doença de Crohn/tratamento farmacológico , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Vinculina , Fator de Necrose Tumoral alfa/uso terapêutico , Antineoplásicos/uso terapêutico , Indução de Remissão , Infliximab/uso terapêutico
2.
Int J Mol Sci ; 24(3)2023 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-36768881

RESUMO

Circulating tumor cells (CTCs), and particularly circulating cancer stem cells (cCSC), are prognostic biomarkers for different malignancies and may be detected using liquid biopsies. The ex vivo culture of cCSCs would provide valuable information regarding biological aggressiveness and would allow monitoring the adaptive changes acquired by the tumor in real time. In this prospective pilot study, we analyzed the presence of EpCAM+ CTCs using the IsoFlux system in the peripheral blood of 37 patients with hepatocellular carcinoma undergoing transarterial chemoembolization (TACE). The average patient age was 63.5 ± 7.9 years and 91.9% of the patients were men. All patients had detectable CTCs at baseline and 20 patients (54.1%) showed CTC aggregates or clusters in their peripheral blood. The increased total tumor diameter (OR: 2.5 (95% CI: 1.3-4.8), p = 0.006) and the absence of clusters of CTCs at baseline (OR: 0.2 (95% CI: 0.0-1.0), p = 0.049) were independent predictors of a diminished response to TACE. Culture of cCSC was successful in five out of thirty-three patients, mostly using negative enrichment of CD45- cells, ultra-low adherence, high glucose, and a short period of hypoxia followed by normoxia. In conclusion, the identification of clusters of CTCs before TACE and the implementation of standardized approaches for cCSC culture could aid to predict outcomes and to define the optimal adjuvant therapeutic strategy for a true personalized medicine in hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Células Neoplásicas Circulantes , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Carcinoma Hepatocelular/patologia , Células Neoplásicas Circulantes/patologia , Neoplasias Hepáticas/patologia , Estudos Prospectivos , Projetos Piloto , Biomarcadores Tumorais
3.
Int J Mol Sci ; 22(23)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34884878

RESUMO

Hepatocellular carcinoma (HCC) is the fifth most common neoplasm and a major cause of cancer-related death worldwide. There is no ideal biomarker allowing early diagnosis of HCC and tumor surveillance in patients receiving therapy. Liquid biopsy, and particularly circulating tumor cells (CTCs), have emerged as a useful tool for diagnosis and monitoring therapeutic responses in different tumors. In the present manuscript, we evaluate the current evidence supporting the quantitative and qualitative assessment of CTCs as potential biomarkers of HCC, as well as technical aspects related to isolation, identification, and classification of CTCs. Although the dynamic assessment of CTCs in patients with HCC may aid the decision-making process, there are still many uncertainties and technical caveats to be solved before this methodology has a true impact on clinical practice guidelines. More studies are needed to identify the optimal combination of surface markers, to increase the efficiency of ex-vivo expansion of CTCs, or even to target CTCs as a potential therapeutic strategy to prevent HCC recurrence after surgery or to hamper tumor progression and extrahepatic spreading.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma Hepatocelular/patologia , Biópsia Líquida/métodos , Neoplasias Hepáticas/patologia , Células Neoplásicas Circulantes , Carcinoma Hepatocelular/diagnóstico , Humanos , Neoplasias Hepáticas/diagnóstico
4.
Cancers (Basel) ; 13(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069569

RESUMO

BACKGROUND: In patients with hepatocellular carcinoma (HCC), a complete clearance of circulating tumor cells (CTCs) early after liver transplantation (LT) or surgical resection (LR) could prevent tumor recurrence. METHODS: prospective pilot study including patients with HCC who underwent LR or LT from September 2017 to May 2020. Enumeration of CTCs was performed in peripheral blood samples (7 mL) using the Isoflux® system (Fluxion Biosciences) immediately before surgery, at post-operative day 5 and at day 30. A clinically relevant number of CTCs was defined as >30 CTCs/sample. RESULTS: 41 HCC patients were included (mean age 58.7 ± 6.3; 82.9% male). LR was performed in 10 patients (24.4%) and 31 patients (75.6%) underwent LT. The main etiology of liver disease was chronic hepatitis C (31.7%). Patients undergoing LR and LT were similar in terms of preoperative CTC count (p = 0.99), but clearance of CTCs within the first month was more pronounced in the LT group. Clusters of CTCs at baseline were associated with incomplete clearance of CTCs at day 30 (54.2% vs. 11.8%, p = 0.005), which in turn impacted negatively on survival (p = 0.038). CONCLUSION: Incomplete clearance of CTCs after surgery could be a surrogate marker of HCC aggressiveness.

5.
Anticancer Agents Med Chem ; 19(11): 1388-1398, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31038079

RESUMO

BACKGROUND: Parallel to the safety of liver resections, new chemotherapy drugs have emerged for the control of liver metastases. However, there is unclear evidence about the combination of intensive BVZ-therapy and extended resections. The main aim was to analyse the impact of Bevacizumab (BVZ) in terms of liver safety and tolerability in two experimental models: a basal-toxicity situation and after major hepatectomy. METHODS: Eighty male-Wistar rats were grouped as toxicity analysis (sham-operated rats-OS-) and regeneration after- surgery analysis (hepatectomy rats-H-). Eight further subgroups were created according to sacrifice (6- hours-6h- or 24-hours-24h-) and dose (µg) of BVZ (none, 100, 200, 400). Several measurements were performed, including biochemical serum samples, histopathological analysis, cytokines (IL-6, TNF-α, TGF-ß), oxidative-stress (GSH/GSSG, ATP), lipid-peroxidation (TBARS) and epidermal and vascular endothelium growth-factors (EGF and VEGF). RESULTS: In the toxicity analysis, safe results with BVZ were observed, with no significant differences among the groups. A trend towards a lower oxidative status was observed in the OS 6 h-100, -200 and -400 versus the OS 6 h-none group. Similar results were observed in the hepatectomy model, with stable oxidative-stress-index and IL-6, TNF- α, and TGF- ß levels. Despite higher lipid peroxidation status, overall regeneration was preserved. As expected, VEGF was almost undetectable in BVZ-treated groups after resection, but not in the non-resection group. CONCLUSION: It was concluded that liver status was not impaired by BVZ even at the high-dose. Similarly, liver regeneration after extended hepatectomy in BVZ-treated animals was well-preserved. Extended liver resections may be encouraged in BVZ-treated patients due to its excellent tolerability and good liver regeneration status.


Assuntos
Bevacizumab/farmacologia , Hepatectomia , Fígado/efeitos dos fármacos , Fígado/cirurgia , Animais , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Cinética , Peroxidação de Lipídeos , Fígado/metabolismo , Masculino , Estrutura Molecular , Estresse Oxidativo , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Fatores de Crescimento do Endotélio Vascular/metabolismo
6.
J Clin Endocrinol Metab ; 104(8): 3389-3402, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30901032

RESUMO

CONTEXT: Nonalcoholic fatty liver disease (NAFLD) is a common obesity-associated pathology characterized by hepatic fat accumulation, which can progress to fibrosis, cirrhosis, and hepatocellular carcinoma. Obesity is associated with profound changes in gene-expression patterns of the liver, which could contribute to the onset of comorbidities. OBJECTIVE: As these alterations might be linked to a dysregulation of the splicing process, we aimed to determine whether the dysregulation in the expression of splicing machinery components could be associated with NAFLD. PARTICIPANTS: We collected 41 liver biopsies from nonalcoholic individuals with obesity, with or without hepatic steatosis, who underwent bariatric surgery. INTERVENTIONS: The expression pattern of splicing machinery components was determined using a microfluidic quantitative PCR-based array. An in vitro approximation to determine lipid accumulation using HepG2 cells was also implemented. RESULTS: The liver of patients with obesity and steatosis exhibited a severe dysregulation of certain splicing machinery components compared with patients with obesity without steatosis. Nonsupervised clustering analysis allowed the identification of three molecular phenotypes of NAFLD with a unique fingerprint of alterations in splicing machinery components, which also presented distinctive hepatic and clinical-metabolic alterations and a differential response to bariatric surgery after 1 year. In addition, in vitro silencing of certain splicing machinery components (i.e., PTBP1, RBM45, SND1) reduced fat accumulation and modulated the expression of key de novo lipogenesis enzymes, whereas conversely, fat accumulation did not alter spliceosome components expression. CONCLUSION: There is a close relationship between splicing machinery dysregulation and NAFLD development, which should be further investigated to identify alternative therapeutic targets.


Assuntos
Hepatopatia Gordurosa não Alcoólica/genética , Obesidade/genética , Splicing de RNA , Adulto , Cirurgia Bariátrica , Biópsia , Técnicas de Cultura de Células , Endonucleases/genética , Feminino , Células Hep G2 , Ribonucleoproteínas Nucleares Heterogêneas/genética , Humanos , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Obesidade/cirurgia , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Período Pós-Operatório , Proteínas de Ligação a RNA/genética
7.
Int J Mol Sci ; 20(2)2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30650598

RESUMO

(1) Background: The mammalian target of rapamycin (mTOR) pathway activation is critical for hepatocellular carcinoma (HCC) progression. We aimed to evaluate the mTOR tissue expression in liver transplant (LT) patients and to analyse its influence on post-LT outcomes. (2) Methods: Prospective study including a cohort of HCC patients who underwent LT (2012⁻2015). MTOR pathway expression was evaluated in the explanted liver by using the "PathScan Intracellular Signalling Array Kit" (Cell Signalling). Kaplan-Meier and Cox regression analyses were performed to evaluate post-LT HCC recurrence. (3) Results: Forty-nine patients were included (average age 56.4 ± 6, 14.3% females). Phospho-mTOR (Ser2448) was over-expressed in peritumoral tissue as compared with tumoral tissue (ΔSignal 22.2%; p < 0.001). The mTOR activators were also increased in peritumoral tissue (phospho-Akt (Thr308) ΔSignal 18.2%, p = 0.004; phospho-AMPKa (Thr172) ΔSignal 56.3%, p < 0.001), as they were the downstream effectors responsible for cell growth/survival (phospho-p70S6K (Thr389) ΔSignal 33.3%, p < 0.001 and phospho-S6RP (Ser235/236) ΔSignal 54.6%, p < 0.001). MTOR expression was increased in patients with multinodular HCC (tumoral p = 0.01; peritumoral p = 0.001). Increased phospho-mTOR in tumoral tissue was associated with higher HCC recurrence rates after LT (23.8% vs. 5.9% at 24 months, p = 0.04). (4) Conclusion: mTOR pathway is over-expressed in patients with multinodular HCC and is it associated with increased post-LT tumour recurrence rates.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Transplante de Fígado , Recidiva Local de Neoplasia/patologia , Serina-Treonina Quinases TOR/genética , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fosforilação , Modelos de Riscos Proporcionais , Curva ROC , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
8.
PLoS One ; 11(8): e0160525, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27490694

RESUMO

The harmful effects of bile acid accumulation occurring during cholestatic liver diseases have been associated with oxidative stress increase and endothelial nitric oxide synthase (NOS-3) expression decrease in liver cells. We have previously reported that glycochenodeoxycholic acid (GCDCA) down-regulates gene expression by increasing SP1 binding to the NOS-3 promoter in an oxidative stress dependent manner. In the present study, we aimed to investigate the role of transcription factor (TF) AP-1 on the NOS-3 deregulation during GCDCA-induced cholestasis. The cytotoxic response to GCDCA was characterized by 1) the increased expression and activation of TFs cJun and c-Fos; 2) a higher binding capability of these at position -666 of the NOS-3 promoter; 3) a decrease of the transcriptional activity of the promoter and the expression and activity of NOS-3; and 4) the expression increase of cyclin D1. Specific inhibition of AP-1 by the retinoid SR 11302 counteracted the cytotoxic effects induced by GCDCA while promoting NOS-3 expression recovery and cyclin D1 reduction. NOS activity inhibition by L-NAME inhibited the protective effect of SR 11302. Inducible NOS isoform was no detected in this experimental model of cholestasis. Our data provide direct evidence for the involvement of AP-1 in the NOS-3 expression regulation during cholestasis and define a critical role for NOS-3 in regulating the expression of cyclin D1 during the cell damage induced by bile acids. AP-1 appears as a potential therapeutic target in cholestatic liver diseases given its role as a transcriptional repressor of NOS-3.


Assuntos
Apoptose/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Ácido Glicoquenodesoxicólico/toxicidade , Óxido Nítrico Sintase Tipo III/metabolismo , Retinoides/farmacologia , Fator de Transcrição AP-1/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Ciclina D1/antagonistas & inibidores , Ciclina D1/metabolismo , Genes Reporter , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Estresse Oxidativo/efeitos dos fármacos , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Retinoides/química , Retinoides/metabolismo , Fator de Transcrição AP-1/antagonistas & inibidores , Regulação para Cima/efeitos dos fármacos
9.
Biochem Pharmacol ; 96(1): 39-51, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25931146

RESUMO

During the course of cholestatic liver diseases, the toxic effect of bile acids accumulation has been related to the decreased expression of endothelial nitric oxide synthase (NOS-3) and cellular oxidative stress increase. In the present study, we have investigated the relationship between these two biological events. In the human hepatocarcinoma cell line HepG2, cytotoxic response to GCDCA was characterized by the reduced activity of the respiratory complexes II+III, the increased expression and activation of the transcription factor Sp1, and a higher binding capacity of this at positions -1386, -632 and -104 of the NOS-3 promoter (pNOS-3). This was associated with a decreased promoter activity and a consequent reduction of NOS-3 expression. The use of antioxidants in GCDCA-treated cells caused a lower activation of Sp1 and the recovery of the pNOS-3 activity and NOS-3 expression and activity. Similarly, the specific inhibition of Sp1 resulted in the improvement of NOS-3 expression. Both, antioxidant treatment and Sp1 inhibition were associated with the reduction of cell death-related parameters. Bile duct ligation in rats confirmed in vitro results concerning the activation of Sp1 and the reduction of NOS-3 expression. Our results provide direct evidence for the involvement of Sp1 in the regulation of NOS-3 expression during cholestasis. Thus, the identification of Sp1 as a potential negative regulator of NOS-3 expression represents a new mechanism by which the accumulation of bile acids causes a cytotoxic effect through the oxidative stress increase, and provides a new potential target in cholestatic liver diseases.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Ácido Glicoquenodesoxicólico/farmacologia , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo , Regiões Promotoras Genéticas , Fator de Transcrição Sp1/metabolismo , Animais , Sequência de Bases , Linhagem Celular Tumoral , DNA , Humanos , Masculino , Dados de Sequência Molecular , Óxido Nítrico Sintase Tipo III/genética , Ligação Proteica , Ratos , Ratos Wistar
10.
PLoS One ; 10(3): e0118527, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25789864

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common and lethal cancers in the world, with limited options for treatment unless timely diagnosed. Chronic hepatitis C virus (HCV) infection and persistent heavy alcohol consumption are independent risk factors for HCC development, which may induce a specific protein expression pattern different from those caused separately. The aim of the study was to identify protein biomarkers for the detection of HCC in HCV-infected alcoholic patients with cirrhosis in order to improve survival. We compared protein expression profiles of plasma samples from 52 HCV-infected alcoholic patients with and without HCC, using 2-D DIGE coupled with MALDI-TOF/TOF mass spectrometry. The 2-D DIGE results were analyzed statistically using Decyder software, and verified by western-blot and ELISA. In plasma samples from HCV-infected alcoholic patients, we found significantly differential expression profiles of carboxypeptidase-N, ceruloplasmin (CP), complement component 4a (C4a), fibrinogen-alpha (FGA), immunoglobulin mu chain C region, serum albumin, and serum paraoxonase/arylesterase 1 (PON1). Deregulation of plasma/serum levels of the identified proteins was associated to HCV, ethanol consumption, and/or HCC progression. In the validation through ELISA, C4a serum concentration was increased in HCC patients (2.4±1 ng/mg vs 1.8±0.6 ng/mg; p = 0.029), being the only independent predictor of HCC in the multivariate analysis (OR = 2.15; p = 0.015), with an AUROC = 0.70. The combination of C4a, FGA, CP and PON1 improved slightly the predictive ability of C4a alone (AUROC 0.81). In conclusion, we identified proteins related to acute-phase response, oxidative stress, or immune response, whose differential expression in plasma may be attributed to the presence of HCC. Among them, C4a, and its combination with CP, FGA and PON1, could be considered as potentially reliable biomarkers for the detection of HCC in HCV-infected alcoholic patients.


Assuntos
Alcoolismo/complicações , Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/diagnóstico , Hepatite C/complicações , Cirrose Hepática/etiologia , Neoplasias Hepáticas/diagnóstico , Western Blotting , Carcinoma Hepatocelular/sangue , Ensaio de Imunoadsorção Enzimática , Hepatite C/sangue , Humanos , Cirrose Hepática/sangue , Neoplasias Hepáticas/sangue , Software
11.
Biochim Biophys Acta ; 1853(5): 1182-94, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25712867

RESUMO

Stable overexpression of endothelial nitric oxide synthase (NOS-3) in HepG2 cells (4TO-NOS) leads to increased nitro-oxidative stress and upregulation of the cell death mediators p53 and Fas. Thus, NOS-3 overexpression has been suggested as a useful antiproliferative mechanism in hepatocarcinoma cells. We aimed to identify the underlying mechanism of cell death induced by NOS-3 overexpression at basal conditions and with anti-Fas treatment. The intracellular localization of NOS-3, the nitro-oxidative stress and the mitochondrial activity were analysed. In addition, the protein expression profile in 4TO-NOS was screened for differentially expressed proteins potentially involved in the induction of apoptosis. NOS-3 localization in the mitochondrial outer membrane was not associated with changes in the respiratory cellular capacity, but was related to the mitochondrial biogenesis increase and with a higher protein expression of mitochondrial complex IV. Nitro-oxidative stress and cell death in NOS-3 overexpressing cells occurred with the expression increase of pro-apoptotic genes and a higher expression/activity of the enzymes adrenodoxin reductase mitochondrial (AR) and cathepsin D (CatD). CatD overexpression in 4TO-NOS was related to the apoptosis induction independently of its catalytic activity. In addition, CatD activity inhibition by pepstatin A was not effective in blocking apoptosis induced by anti-Fas. In summary, NOS-3 overexpression resulted in an increased sensitivity to anti-Fas induced cell death, independently of AR expression and CatD activity.


Assuntos
Catepsina D/metabolismo , Ferredoxina-NADP Redutase/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Receptor fas/metabolismo , Morte Celular , Respiração Celular , DNA Mitocondrial/genética , Dosagem de Genes , Células Hep G2 , Humanos , Membranas Mitocondriais/metabolismo , Renovação Mitocondrial , Modelos Biológicos , Fosforilação Oxidativa , Estresse Oxidativo , Transporte Proteico , Proteoma/metabolismo , Proteômica
12.
Toxicol Appl Pharmacol ; 242(2): 165-72, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19837105

RESUMO

The intracellular oxidative stress has been involved in bile acid-induced cell death in hepatocytes. Nitric oxide (NO) exerts cytoprotective properties in glycochenodeoxycholic acid (GCDCA)-treated hepatocytes. The study evaluated the involvement of Ca2+ on the regulation of NO synthase (NOS)-3 expression during N-acetylcysteine (NAC) cytoprotection against GCDCA-induced cell death in hepatocytes. The regulation of Ca2+ pools (EGTA or BAPTA-AM) and NO (L-NAME or NO donor) production was assessed during NAC cytoprotection in GCDCA-treated HepG2 cells. The stimulation of Ca2+ entrance was induced by A23187 in HepG2. Cell death, Ca2+ mobilization, NOS-1, -2 and -3 expression, AP-1 activation, and NO production were evaluated. GCDCA reduced intracellular Ca2+ concentration and NOS-3 expression, and enhanced cell death in HepG2. NO donor prevented, and l-NAME enhanced, GCDCA-induced cell death. The reduction of Ca2+ entry by EGTA, but not its release from intracellular stores by BAPTA-AM, enhanced cell death in GCDCA-treated cells. The stimulation of Ca2+ entrance by A23187 reduced cell death and enhanced NOS-3 expression in GCDCA-treated HepG2 cells. The cytoprotective properties of NAC were related to the recovery of intracellular Ca2+ concentration, NOS-3 expression and NO production induced by GCDCA-treated HepG2 cells. The increase of NO production by Ca2+-dependent NOS-3 expression during NAC administration reduces cell death in GCDCA-treated hepatocytes.


Assuntos
Acetilcisteína/farmacologia , Cálcio/metabolismo , Morte Celular/efeitos dos fármacos , Ácido Glicoquenodesoxicólico/farmacologia , Hepatócitos/efeitos dos fármacos , Óxido Nítrico/biossíntese , Sequência de Bases , Linhagem Celular , Hepatócitos/metabolismo , Humanos , Oligodesoxirribonucleotídeos
13.
Chem Res Toxicol ; 22(12): 1984-91, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20020783

RESUMO

Ca(2+) mobilization, nitric oxide (NO), and oxidative stress have been involved in cell death induced by hydrophobic bile acid in hepatocytes. The aim of the study was the elucidation of the effect of the antioxidant mitochondrial-driven ubiquinone (Mito Q) on the intracellular Ca(2+) concentration, NO production, and cell death in glycochenodeoxycholic acid (GCDCA)-treated HepG2 cells. The role of the regulation of the intracellular Ca(2+) concentration by Ca(2+) chelators (EGTA or BAPTA-AM), agonist of Ca(2+) entrance (A23187) or NO (L-NAME or NO donor), was assessed during Mito Q cytoprotection in GCDCA-treated HepG2 cells. Cell death, NO synthase (NOS)-1, -2, and -3 expression, Ca(2+) mobilization, and NO production were evaluated. GCDCA reduced the intracellular Ca(2+) concentration and NOS-3 expression and enhanced cell death in HepG2. NO donor prevented and L-NAME enhanced GCDCA-induced cell death. The reduction of Ca(2+) entry by EGTA, but not its release from intracellular stores by BAPTA-AM, reduced the expression of NOS-3 and enhanced cell death in control and GCDCA-treated cells. Mito Q prevented the reduction of intracellular Ca(2+) concentration, NOS-3 expression, NO production, and cell death in GCDCA-treated HepG2 cells. The conclusion is that the recovery of Ca(2+)-dependent NOS-3 expression by Mito Q may be considered an additional cytoprotective property of an antioxidant.


Assuntos
Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Ácido Glicoquenodesoxicólico/química , Hepatócitos/metabolismo , Mitocôndrias/metabolismo , Óxido Nítrico/metabolismo , Ubiquinona/metabolismo , Calcimicina/farmacologia , Caspase 3/metabolismo , Ácido Glicoquenodesoxicólico/toxicidade , Células Hep G2 , Humanos , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo
14.
Int J Cancer ; 125(10): 2270-80, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19672859

RESUMO

Hepatocellular carcinoma (HCC) is the fifth most commonly occurring cancer worldwide. The expression of p27 has been related to reduced severity of tumor grade and recurrence of HCC. The study assessed the role of p27 on the cell proliferation and death, and DNA mutagenesis in experimental genotoxicity induced by aflatoxin B1 (AFB(1)) in cultured hepatocytes obtained from control and p27(Kip1) deficient mice. The overexpression of p27 was assessed with wild type p27(Kip1) expression vector in HepG2 cells. The expression of p27, p21 and p53 was assessed in well and poorly-differentiated liver tumors. DNA damage and cell death induced by AFB(1) were related to a reduction of p27 and p21 expression in cultured hepatocytes. AFB(1)-induced nuclear phosphorylated (Ser 10) p27 degradation was related to a rise of nuclear KIST, Rsk-1 and Rsk-2 expression and cytoplasm phosphorylated (Thr 198) p27 expression. The overexpression of p27 reduced cell proliferation, cell death and DNA damage in AFB(1)-treated hepatocytes. The enhanced survival of patients with well differentiated compared to poorly-differentiated tumors was related to high expression of p27, p21 and p53 in liver sections. The study showed that the p27 reduced cell proliferation and death, as well as the accumulation of DNA damage in hepatocarcinogenesis.


Assuntos
Apoptose , Carcinoma Hepatocelular/patologia , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p27/fisiologia , Dano ao DNA , Modelos Animais de Doenças , Neoplasias Hepáticas/patologia , Aflatoxina B1/toxicidade , Animais , Western Blotting , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Técnicas Imunoenzimáticas , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
15.
Innate Immun ; 15(6): 337-49, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19710104

RESUMO

Hepatic steatosis is a risk factor for the progression of non-alcoholic fatty liver disease. The role of pro-inflammatory interleukin (IL)-6 in hepatic steatosis etiology is controversial. We investigated in vivo and in primary hepatocyte cultures whether IL-6 has a modulator role in liver and mitochondria lipid composition and cell death in a choline-deficient (CD) diet rat model of hepatic steatosis. Dietary choline deficiency increased triglycerides and cholesterol, and reduced phosphatidylcholine (PC), phosphatidylethanolamine (PE) and the membrane integrity marker PC:PE ratio in liver. Choline-deficient diet enhanced systemic IL-6, and IL-6 receptor expression and cell death vulnerability in hepatocytes. Derangement of the mitochondrial electron transport chain and of its phospholipid environment was found in CD rat liver mitochondria, which exhibited elevated concentrations of triglycerides, cardiolipin and PC and elevated PC:PE ratio. The cell treatment with IL-6, but not PC, eliminated much of the CD-promoted lipid imbalance in mitochondria but not tumor-necrosis factor (TNF)-alpha-induced cell death. However, PC supplementation prevented the TNF-alpha-induced DNA fragmentation, cytochrome-c release and caspase-3 activity in control and CD hepatocytes. In conclusion, IL-6 ameliorated the mitochondria lipid disturbance in hepatocytes isolated from steatotic animals. Furthermore, PC is identified as a new survival agent that reverses several TNFalpha-inducible responses that are likely to promote steatosis and necrosis.


Assuntos
Deficiência de Colina/imunologia , Fígado Gorduroso/imunologia , Hepatócitos/metabolismo , Interleucina-6/metabolismo , Receptores de Interleucina-6/biossíntese , Animais , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/imunologia , Células Cultivadas , Deficiência de Colina/tratamento farmacológico , Deficiência de Colina/fisiopatologia , Dieta , Modelos Animais de Doenças , Progressão da Doença , Transporte de Elétrons/efeitos dos fármacos , Transporte de Elétrons/imunologia , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Fígado Gorduroso/fisiopatologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/imunologia , Hepatócitos/patologia , Interleucina-6/farmacologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/fisiologia , Fosfatidilcolinas/farmacologia , Ratos , Ratos Wistar , Receptores de Interleucina-6/genética , Triglicerídeos/biossíntese , Triglicerídeos/genética , Fator de Necrose Tumoral alfa/imunologia
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