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1.
Cancers (Basel) ; 15(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37296898

RESUMO

Tenofovir disoproxil fumarate (TDF) is reportedly superior or at least comparable to entecavir (ETV) in preventing hepatocellular carcinoma (HCC) among chronic hepatitis B (CHB) patients; however, it remains controversial. This study aimed to conduct comprehensive comparisons between the two antivirals. CHB patients initially treated with ETV or TDF between 2012 and 2015 at 20 referral centers in Korea were included. The primary outcome was the cumulative incidence of HCC. The secondary outcomes included death or liver transplantation, liver-related outcome, extrahepatic malignancy, development of cirrhosis, decompensation events, complete virologic response (CVR), seroconversion rate, and safety. Baseline characteristics were balanced using the inverse probability of treatment weighting (IPTW). Overall, 4210 patients were enrolled: 1019 received ETV and 3191 received TDF. During the median follow-ups of 5.6 and 5.5 years, 86 and 232 cases of HCC were confirmed in the ETV and TDF groups, respectively. There was no difference in HCC incidence between the groups both before (p = 0.36) and after IPTW was applied (p = 0.81). Although the incidence of extrahepatic malignancy was significantly higher in the ETV group than in the TDF group before weighting (p = 0.02), no difference was confirmed after IPTW (p = 0.29). The cumulative incidence rates of death or liver transplantation, liver-related outcome, new cirrhosis development, and decompensation events were also comparable in the crude population (p = 0.24-0.91) and in the IPTW-adjusted population (p = 0.39-0.80). Both groups exhibited similar rates of CVR (ETV vs. TDF: 95.1% vs. 95.8%, p = 0.38), and negative conversion of hepatitis B e antigen (41.6% vs. 37.2%, p = 0.09) or surface antigen (2.8% vs. 1.9%, p = 0.10). Compared to the ETV group, more patients in the TDF group changed initial antivirals due to side effects, including decreased kidney function (n = 17), hypophosphatemia (n = 20), and osteoporosis (n = 18). In this large-scale multicenter study, ETV and TDF demonstrated comparable effectiveness across a broad range of outcomes in patients with treatment-naïve CHB during similar follow-up periods.

2.
J Hepatol ; 77(4): 967-977, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35714812

RESUMO

BACKGROUND & AIMS: Bepirovirsen, an antisense oligonucleotide targeting pregenomic and mRNA transcripts of HBV, has been conjugated to N-acetyl galactosamine (GSK3389404) to enhance hepatocyte delivery. This dose-finding study was the first to assess GSK3389404 for chronic HBV infection. METHODS: This phase IIa, randomised, double-blind, placebo-controlled, 2-part study was conducted in 22 centres in Asia (NCT03020745). Pharmacokinetic findings from Part 1 informed Part 2 dosing. In Part 2, patients with chronic hepatitis B on nucleos(t)ide analogue therapy were randomised 11:2 to GSK3389404 (30, 60, 120 mg weekly or 120 mg bi-weekly) or placebo until Day 85. Coprimary endpoints included HBsAg response (≥1.5 log10 IU/ml reduction from baseline) rate, safety and pharmacokinetics. RESULTS: Parts 1 and 2 included 12 (9 GSK3389404, 3 placebo) and 66 patients (56 GSK3389404, 10 placebo), respectively. In Part 2, one patient each in the 60 mg weekly, 120 mg weekly and 120 mg bi-weekly arms achieved a HBsAg response. HBsAg reductions were dose-dependent (Day 85: mean 0.34 [60 mg weekly] to 0.75 log10 IU/ml [120 mg weekly]) and occurred in hepatitis B e antigen-positive and -negative patients. No patient achieved HBsAg seroclearance. 43/56 (77%) GSK3389404- and 9/10 (90%) placebo-treated patients reported adverse events. No deaths were reported. Alanine aminotransferase flares (>2x upper limit of normal) occurred in 2 GSK3389404-treated patients (120 mg weekly, 120 mg bi-weekly); both were associated with decreased HBsAg, but neither was considered a responder. GSK3389404 plasma concentrations peaked 2-4 hours post dose; mean plasma half-life was 3-5 hours. CONCLUSIONS: GSK3389404 showed an acceptable safety profile and target engagement, with dose-dependent reductions in HBsAg. However, no efficacious dosing regimen was identified. CLINICAL TRIAL NUMBER: NCT03020745. LAY SUMMARY: Hepatitis B virus (HBV) can result in chronic HBV infection, which may ultimately lead to chronic liver disease, primary liver cancer and death; HBV proteins may prevent the immune system from successfully controlling the virus. GSK3389404 is an investigational agent that targets HBV RNA, resulting in reduced viral protein production. This study assessed the safety of GSK3389404 and its ability to reduce the viral proteins in patients with chronic HBV infection. GSK3389404 showed dose-dependent reduction in hepatitis B surface antigen, with an acceptable safety profile. While no clear optimal dose was identified, the findings from this study may help in the development of improved treatment options for patients with chronic HBV infections.


Assuntos
Hepatite B Crônica , Alanina Transaminase , Antivirais/efeitos adversos , DNA Viral , Método Duplo-Cego , Galactosamina/uso terapêutico , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Vírus da Hepatite B/genética , Humanos , Oligonucleotídeos Antissenso/uso terapêutico , RNA , RNA Mensageiro , Proteínas Virais
3.
Nat Med ; 27(10): 1725-1734, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34642494

RESUMO

Chronic infection with hepatitis B virus (HBV) leads to an increased risk of death from cirrhosis and hepatocellular carcinoma. Functional cure rates are low with current treatment options (nucleos(t)ide analogs (NAs) and pegylated interferons). Bepirovirsen is an antisense oligonucleotide targeting all HBV messenger RNAs; in cell culture and animal models, bepirovirsen leads to reductions in HBV-derived RNAs, HBV DNA and viral proteins. This phase 2 double-blinded, randomized, placebo-controlled trial is the first evaluation of the safety and activity of an antisense oligonucleotide targeting HBV RNA in both treatment-naïve and virally suppressed individuals with chronic HBV infection. The primary objective was to assess the safety and tolerability of bepirovirsen in individuals with chronic hepatitis B (CHB) (NCT02981602). The secondary objective was to assess antiviral activity, including the change from baseline to day 29 in serum hepatitis B surface antigen (HBsAg) concentration. Participants with CHB infection ≥6 months and serum HBsAg ≥50 IU ml-1 were enrolled from seven centers across Hong Kong and the Republic of Korea and randomized (3:1 within each dose cohort) to receive bepirovirsen or placebo via subcutaneous injection twice weekly during weeks 1 and 2 (days 1, 4, 8 and 11) and once weekly during weeks 3 and 4 (days 15 and 22). Participants were then followed for 26 weeks. Twenty-four participants were treatment-naïve and seven were receiving stable NA therapy. Treatment-emergent adverse events were mostly mild/moderate (most commonly injection site reactions). Eleven (61.1%) and three (50.0%) treatment-naïve participants experienced one or more treatment-emergent adverse event in the bepirovirsen and placebo groups, respectively. In participants receiving NA therapy, the corresponding numbers were three (60.0%) and one (50.0%). Transient, self-resolving alanine aminotransferase flares (≥2× upper limit of normal) were observed in eight treatment-naïve participants and three participants on stable NA regimens in the bepirovirsen treatment arms. HBsAg reductions were observed and were significant versus placebo for treatment-naïve participants receiving bepirovirsen 300 mg (P = 0.001), but not for the bepirovirsen 150 mg group (P = 0.245) or participants receiving stable NA therapy (P = 0.762). Two participants in each of the 300 mg dose groups achieved HBsAg levels below the lower limit of quantitation by day 29 (n = 3) or day 36 (n = 1). Bepirovirsen had a favorable safety profile. These preliminary observations warrant further investigation of the safety and activity of bepirovirsen in a larger CHB patient population.


Assuntos
Antivirais/administração & dosagem , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Oligonucleotídeos Antissenso/administração & dosagem , Adolescente , Adulto , Antivirais/efeitos adversos , Quimioterapia Combinada , Feminino , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/sangue , Hepatite B Crônica/genética , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Oligonucleotídeos Antissenso/efeitos adversos , Placebos , Polietilenoglicóis/química , República da Coreia/epidemiologia , Adulto Jovem
4.
ACS Nano ; 14(9): 11040-11054, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32816451

RESUMO

As well as the exploration of translatable delivery nanosystems for cancer therapeutic agents, the development of automatable continuous-flow manufacturing technology comprising digitally controlled reactions for the on-demand production of pharmaceuticals is an important challenge in anticancer nanomedicine. Most attempts to resolve these issues have involved the development of alternative reactions, formulations, or constructs containing stimulus components aimed at producing multiple approaches for highly efficacious combination cancer therapies. However, there has been no report of a platform based on plug-in execution that enables continuous-flow manufacture in a compact, reconfigurable manner, although an optimal platform technology may be a prerequisite for the timely translation of recently developed nanomedicines. To this end, we describe the development of a platform toward digitizable, continuous manufacture by a serial combination of plug-in reactionwares (heating plates, a spraying cup, and a photochamber) for single-pass flow fabrication. Specifically, we fabricated three different composite nanoblocks consisting of Au1Ag9 (<8 nm; stimulus component), docetaxel (an anticancer drug), and bovine serum albumin (a protective and targeting agent) using our system, with the result of producing nanoblocks with photothermally modulatable and structurally disintegratable properties. These were examined for effectiveness in near-infrared-induced chemothermal cancer therapy and renal excretion of Au1Ag9 particles and exhibited high anticancer efficacy and warrantable biosafety.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/uso terapêutico , Humanos , Nanomedicina , Neoplasias/tratamento farmacológico , Fototerapia , Prata/uso terapêutico
5.
Bone ; 118: 89-98, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29366839

RESUMO

Unlike white and brown adipose tissues, the bone marrow adipocyte (BMA) exists in a microenvironment containing unique populations of hematopoietic and skeletal cells. To study this microenvironment at the sub-cellular level, we performed a three-dimensional analysis of the ultrastructure of the BMA niche with focused ion beam scanning electron microscopy (FIB-SEM). This revealed that BMAs display hallmarks of metabolically active cells including polarized lipid deposits, a dense mitochondrial network, and areas of endoplasmic reticulum. The distinct orientations of the triacylglycerol droplets suggest that fatty acids are taken up and/or released in three key areas - at the endothelial interface, into the hematopoietic milieu, and at the bone surface. Near the sinusoidal vasculature, endothelial cells send finger-like projections into the surface of the BMA which terminate near regions of lipid within the BMA cytoplasm. In some regions, perivascular cells encase the BMA with their flattened cellular projections, limiting contacts with other cells in the niche. In the hematopoietic milieu, BMAT adipocytes of the proximal tibia interact extensively with maturing cells of the myeloid/granulocyte lineage. Associations with erythroblast islands are also prominent. At the bone surface, the BMA extends organelle and lipid-rich cytoplasmic regions toward areas of active osteoblasts. This suggests that the BMA may serve to partition nutrient utilization between diverse cellular compartments, serving as an energy-rich hub of the stromal-reticular network. Lastly, though immuno-EM, we've identified a subset of bone marrow adipocytes that are innervated by the sympathetic nervous system, providing an additional mechanism for regulation of the BMA. In summary, this work reveals that the bone marrow adipocyte is a dynamic cell with substantial capacity for interactions with the diverse components of its surrounding microenvironment. These local interactions likely contribute to its unique regulation relative to peripheral adipose tissues.


Assuntos
Adipócitos/ultraestrutura , Medula Óssea/ultraestrutura , Imageamento Tridimensional , Microscopia Eletrônica , Nicho de Células-Tronco , Adipócitos/citologia , Animais , Comunicação Celular , Células Endoteliais/citologia , Células Endoteliais/ultraestrutura , Eritrócitos/citologia , Células-Tronco Hematopoéticas/citologia , Masculino , Camundongos Endogâmicos C57BL
6.
Appl Bionics Biomech ; 2018: 9730525, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29515650

RESUMO

Periacetabular osteotomy (PAO) is a complex surgical procedure to restore acetabular coverage in the dysplastic hip, and the amount of acetabular rotation during PAO plays a key role. Using computational simulations, this study assessed the optimal direction and amount of the acetabular rotation in three dimensions for a patient undergoing PAO. Anatomy-specific finite element (FE) models of the hip were constructed based on clinical CT images. The calculated acetabular rotation during PAO were 9.7°, 18°, and 4.3° in sagittal, coronal, and transverse planes, respectively. Based on the actual acetabular rotations, twelve postoperative FE models were generated. An optimal position was found by gradually varying the amount of the acetabular rotations in each anatomical plane. The coronal plane was found to be the principal rotational plane, which showed the strongest effects on joint contact pressure compared to other planes. It is suggested that rotation in the coronal plane of the osteotomized acetabulum is one of the primary surgical parameters to achieve the optimal clinical outcome for a given patient.

7.
Int J Oncol ; 50(1): 185-192, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27922686

RESUMO

A major goal of breast cancer research is to prevent the molecular events that lead to tumour metastasis. It is well-established that both cytoplasmic and mitochondrial reactive oxygen species (ROS) play important roles in cell migration and metastasis. Accordingly, this study examined the molecular mechanisms of the anti-metastatic effects of NecroX-5, a mitochondrial ROS scavenger. NecroX-5 inhibited lung cancer metastasis by ameliorating migration in a mouse model. In human cancer cells, the inhibition of migration by NecroX-5 is cell type-dependent. We observed that the effect of NecroX-5 correlated with a reduction in mitochondrial ROS, but mitochondrial ROS reduction by MitoQ did not inhibit cell migration. NecroX-5 decreased intracellular calcium concentration by blocking Ca2+ influx, which mediated the inhibition of cell migration, AKT downregulation and the reduction of mitochondrial ROS levels. However, the reduction of mitochondrial ROS was not associated with supressed migration and AKT downregulation. Our study demonstrates the potential of NecroX-5 as an inhibitor of breast cancer metastasis.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Compostos Heterocíclicos de 4 ou mais Anéis/administração & dosagem , Proteína Oncogênica v-akt/biossíntese , Sulfonas/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Cálcio/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Metástase Neoplásica , Proteína Oncogênica v-akt/genética , Compostos Organofosforados/administração & dosagem , Espécies Reativas de Oxigênio/metabolismo , Ubiquinona/administração & dosagem , Ubiquinona/análogos & derivados , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Laryngoscope ; 126(11): E379-E385, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27328420

RESUMO

OBJECTIVES/HYPOTHESIS: The purpose of this study was to investigate the effect of early postnatal neurotrophin-3 (NT3) support on hearing acquisition. STUDY DESIGN: A prospective experimental animal study. METHODS: Adenoviral (Ad) vectors expressing green fluorescence protein (GFP) alone or in combination with NT3 were injected into the scala tympani through the round window of 5-postnatal-day-old (P5) rats. Changes in NT3 mRNA level, hearing thresholds, and morphological studies were done after the viral vector injection. RESULTS: NT3 mRNA was significantly increased in the Ad-GFP-NT3 group compared to the normal-developmental group and Ad-GFP alone group. GFP was widely expressed in the cochlea such as in the hair cells, supporting cell area, and spiral ganglion neurons. Auditory brainstem response thresholds were significantly lower in the Ad-GFP-NT3 group compared to the normal-developmental group and Ad-GFP alone group at P15. CONCLUSIONS: These results show that early postnatal NT3 overexpression may accelerate the acquisition of hearing in rats. LEVEL OF EVIDENCE: NA Laryngoscope, 126:E379-E385, 2016.


Assuntos
Vetores Genéticos/administração & dosagem , Proteínas de Fluorescência Verde/administração & dosagem , Audição/genética , Neurotrofina 3/genética , RNA Mensageiro/metabolismo , Animais , Cóclea/crescimento & desenvolvimento , Potenciais Evocados Auditivos do Tronco Encefálico/genética , Técnicas de Transferência de Genes , Terapia Genética/métodos , Estudos Prospectivos , Ratos , Ratos Sprague-Dawley , Janela da Cóclea , Rampa do Tímpano
9.
Radiat Res ; 183(3): 271-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25706775

RESUMO

This study investigated the therapeutic effects of combined local irradiation and anti-HER2/neu antibody in a mixed tumor mouse model comprised of a nonmetastatic neu-positive tumor and a metastatic neu-negative tumor. While local irradiation alone could control the primary tumor in a dose-dependent manner, it did not improve mouse survival. Combined treatment comprised of local irradiation and anti-neu antibody of tumor-bearing BALB/c mice significantly improved mouse survival (P < 0.5), even though the tumor growth was similar to that of the irradiated-alone group. The combined treatment significantly reduced metastatic tumor masses in the lung and increased immune cell infiltration in primary tumor tissues. However, immune deficient nude mice with tumors did not exhibit prolonged survival in response to the combined treatment. Collectively, these results show that combined local irradiation and anti-neu antibody can elicit an immune-mediated abscopal effect to extend survival. Although the mechanism for abscopal effects induced by the combined treatment of radiation and anti-HER2/neu antibody was not elucidated, to our knowledge this is the first published study to describe the abscopal effect induced by the combination of local irradiation and the anti-HER2/neu antibody.


Assuntos
Anticorpos Anti-Idiotípicos/administração & dosagem , Neoplasias da Mama/radioterapia , Imunoterapia , Receptor ErbB-2/imunologia , Animais , Anticorpos Anti-Idiotípicos/imunologia , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Feminino , Humanos , Camundongos , Metástase Neoplásica , Receptor ErbB-2/genética , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Monoclon Antib Immunodiagn Immunother ; 33(5): 312-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25357998

RESUMO

Urokinase-type plasminogen activator (uPA) and uPA receptor (uPAR) are expressed in many tumors and have been reported to be correlated to protein expression and poor prognosis in malignant tumors. In a previous study, we reported on the selection of human single-chain variable fragment (scFv) A8 specific to uPA from phage-displayed human naïve scFv library. In this study, scFv A8 was converted to minibody form and evaluated for its functional ability on the uPA system involved in cellular signaling and cancer cell metastasis. A8 minibody increased enzyme activity of uPA and enhanced the migration and invasion of HT1080 colon cancer cells in a dose-dependent manner. A8 increased ERK phosphorylation, and enhanced migration was blocked by U0126, but not by LY0294002, SB2203580, and SP600125. A8 minibody also enhanced migration of MDA-MB231 by mediated expressing surface uPA, but not that of MCF-7 non-expressing surface uPA. Taken together, the A8 anti-uPA antibody is a uPA agonistic antibody, enhancing migration and invasion of cancer cells that express uPA via activation of ERK pathway.


Assuntos
Anticorpos Monoclonais/imunologia , Sistema de Sinalização das MAP Quinases/imunologia , Metástase Neoplásica/imunologia , Transdução de Sinais/imunologia , Anticorpos de Cadeia Única/imunologia , Ativador de Plasminogênio Tipo Uroquinase/imunologia , Movimento Celular/imunologia , Células HEK293 , Humanos , Células MCF-7 , Fosforilação/imunologia , Receptores de Superfície Celular/imunologia , Células Tumorais Cultivadas
11.
Tuberc Respir Dis (Seoul) ; 76(6): 276-83, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25024721

RESUMO

BACKGROUND: We aimed to investigate the role of the physician in practice and the factors that influence the success rate of smoking cessation. METHODS: This study retrospectively analyzed 126 adult smokers who had visited the outpatient department of pulmonology, and received motivational interviewing with or without supplement drugs. The findings include continuous smoking abstinence rate, which was evaluated at 6, 12 and 24 weeks, and the factors associated with continuous abstinence for 6 months or longer. RESULTS: The patients with only motivational interviewing accounted for 57.9%, while the nicotine patch therapy was applied to 30.2%; and varenicline was prescribed to 11.9%. The smoking cessation success rates of at 6, 12, and 24 weeks were 55.6%, 47.6%, and 33.3%, respectively. However, even in the failure group at six months, tobacco consumption was decreased under 10 cigarettes per day in 42.1% (53/126). In multivariate logistic regression analysis, degree of Fagerstöm Test for Nicotine Dependence (p=0.034; odds ratio, 3.607; 95% confidence interval [CI], 1.102-1.807), the absence of smoking-related lung disease (p=0.008; odds ratio, 4.693; 95% CI, 1.497-14.707), and education level (p=0.001; odds ratio, 181.420; 95% CI, 8.414-3,911.502) were the predictors of successful smoking cessation. CONCLUSION: An improved continuous smoking abstinence rate can be obtained by motivational interviewing, regardless of the association with pharmacotherapy.

12.
Int Immunopharmacol ; 17(3): 721-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24029595

RESUMO

The generation of tryptophan (Trp) metabolites by indoleamine 2,3-dioxygenase (IDO) is an effective mechanism for T cell suppression. However, the effect of Trp metabolites on dendritic cells (DCs) remains unclear. Here, we investigated whether the tryptophan metabolite 3-hydroxyanthranilic acid (3-HAA) directly inhibits DC activation and is responsible for T cell suppression. We found that 3-HAA treatment significantly reduced IL-12, IL-6, and TNF-α production in bone marrow-derived DCs (BMDCs) stimulated with LPS. Maturation markers CD40, CD80, CD86, and I-A were also significantly reduced. Moreover, treatment with 3-HAA decreased the ability of DCs to stimulate T cell activation and differentiation in vitro and in vivo. Finally, we observed that phospho-JNK and phospho-38 levels were reduced in 3-HAA-treated DC2.4 cells and BMDCs. These results suggest that the tryptophan metabolite 3-HAA suppresses T cell responses by inhibiting DC activation.


Assuntos
Ácido 3-Hidroxiantranílico/farmacologia , Células Dendríticas/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Linfócitos T/efeitos dos fármacos , Animais , Células da Medula Óssea/citologia , Células Cultivadas , Citocinas/imunologia , Células Dendríticas/citologia , Células Dendríticas/imunologia , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Baço/citologia , Linfócitos T/citologia , Linfócitos T/imunologia , Triptofano/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
13.
Inflammation ; 35(2): 736-45, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21845471

RESUMO

Extracellular matrix-degrading protease, matrix metalloproteinase-9 (MMP-9), is known to be involved in vascular smooth muscle cell (SMC)'s aberrant proliferation and movement in atherosclerotic lesions. During screening of the MMP-9-inhibitory compounds from marine animal resources, we have found that the ethyl acetate extract from Cliona celata (ECC) effectively inhibits the SMC-derived MMP-9 enzyme activity and gene expression. In addition, the ECC effectively repressed the migration potential of the tumor necrosis factor-α (TNF-α)-stimulated human aortic smooth muscle cell (HASMC). As assessed by Western blot analysis, the produced MMP-9 protein levels in the TNF-α-induced HASMC were significantly decreased by the concomitant treatment of ECC at the 50- to 300-µg/mL concentration ranges. In addition, in the RT-PCR experiment, the expressed MMP-9 mRNA levels in the TNF-α-induced HASMC were seemingly decreased by ECC treatment at the same concentration ranges (50-300 µg/mL). For the action mechanism(s) of ECC to the phenotype changes in HASMC, we have further evaluated the ECC's pharmacological activities on the signal molecules which are importantly linked in the MMP-9 expression and cell migration potential of HASMC. We have found that extracellular signal-regulated kinase 1 and 2 (ERK1/2) phosphorylation as a target point is suppressed by the ECC treatment in the TNF-α-treated HASMC. Using electrophoretic mobility shift assay, the nuclear extracts purified from ECC-treated HASMCs were shown to decrease the binding potentials on the labeled nuclear factor-kappaB (NF-κB) and activator protein 1 probes. NF-κB p65 and phosphorylated c-Jun contents were also decreased in the purified nuclear extracts from the ECC-treated HASMC, as confirmed by Western blot analysis. Finally, it was shown that the ECC-treated HASMCs were less migrated when compared to the TNF-α-treated cells, as confirmed by HASMC migration assays using the 8-µm pore transwell membranes. From these results, it was proposed that ECC has a potentially applicable anti-atherosclerotic activity.


Assuntos
Metaloproteinase 9 da Matriz/metabolismo , NF-kappa B/metabolismo , Poríferos , Fator de Transcrição AP-1/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Regulação para Baixo , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Inibidores de Metaloproteinases de Matriz , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Fosforilação/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
14.
Toxicol In Vitro ; 25(4): 767-73, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21276846

RESUMO

Atherosclerosis is accompanied by the proliferation of human aortic smooth muscle cells (HASMC) and their movement into the intima. Many reports have indicated the involvement of gelatinases (MMP-9 and MMP-2) in this pathogenesis. The ethylacetate fraction from starfish, Asterias amurensis (EFA), harvested from the Korean seaside has an inhibitory effect on MMP-9 and MMP-2 activities, as well as on the expression of MMP-9 in TNF-α induced HASMC in a dose-dependent manner. Also, EFA inhibits the migration of TNF-α induced HASMC in transwells containing gelatin coated plugs. EFA was not cytotoxic to HASMC over the range 0-1mg/ml. By Western-blot analysis, it was revealed that the phosphorylation of extracellular signal regulated kinase (ERK) in TNF-α induced cells was inhibited and nuclear factor kappa B (NF-κB) p65 levels in nuclear extracts were decreased by EFA treatment. In addition, ERK inhibitor (U0126) treated cells exhibited decreased MMP-9 activity in the zymographic assay. From these results, it was found that the gelatinolytic activity was regulated (1) by enzymatic inhibition of both MMP-9 and MMP-2, as well as (2) by the decreased production of MMP-9 via ERK pathways in EFA treated HASMCs. Taken together, it has been shown that EFA has a putative anti-atherosclerotic effect.


Assuntos
Asterias/química , Inibidores de Metaloproteinases de Matriz , Miócitos de Músculo Liso/efeitos dos fármacos , Acetatos/química , Animais , Aorta/citologia , Aorta/efeitos dos fármacos , Aorta/metabolismo , Western Blotting , Movimento Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , MAP Quinases Reguladas por Sinal Extracelular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Coreia (Geográfico) , Miócitos de Músculo Liso/metabolismo , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
15.
Rev Infect ; 1(3): 151-157, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24688607

RESUMO

Hepatitis C virus (HCV) infection in humans is remarkably efficient in establishing viral persistence, leading to the development of liver cirrhosis and hepatocellular carcinoma. CD8+ T cells are involved in controlling HCV infection; but, in chronic HCV patients, severe CD4+ and CD8+ T cell dysfunction has been observed. This suggests that HCV may employ numerous mechanisms to counteract or possibly suppress the host T cell responses. The primary site of HCV replication occurs within hepatocytes in the liver. As a result of liver enodothelial cells perforated by fenestrations, parenchymal cells (hepatocytes) are not separated by a basal membrane, and thereby HCV-infected hepatocytes are extensively capable of interacting with innate immune cells including NK, DC. Recent studies reveal that the function of NK and DC function is significantly impaired in chronic HCV patients. Given a critical role of NK and DC in limiting HCV replication at the early phase of viral infection, it is likely that HCV-infected hepatocytes might be responsible for impairing NK and DC function by enhancing the expression of immunoregulatory molecules (either soluble or cell surface). Thus, this impairment of innate immunity attributes to the failure of generating effective T cell responses to clear HCV infection. In this article, we will review studies highlighting the regulation of innate immunity by HCV and crosstalk between hepatocytes and NK/DC in the hepatic environment.

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