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1.
J Am Heart Assoc ; 11(24): e8067, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36533625

RESUMO

Background Since July 2018, numerous lots of valsartan have been found to be contaminated with N-nitrosodimethylamine (NDMA). We aimed to assess the association between exposure to valsartan products contaminated with NDMA and the risk of cancer. Methods and Results This study was based on data from the Système National des Données de Santé, which is a national database that includes all French residents' health-related expenses. The target population was consumers of valsartan between January 1, 2013 and December 31, 2017, aged between 40 and 80 years old. The association of exposure to contaminated valsartan with the occurrence of any malignancy and cancer by location was evaluated by fitting Cox proportional hazards models weighted by the inverse probability of treatment. A total of 1.4 million subjects without any history of cancer were included. A total of 986 126 and 670 388 patients were exposed to NDMA-contaminated and uncontaminated valsartan, respectively. The use of the NDMA-contaminated valsartan did not increase the overall risk of cancer (adjusted hazard ratio [aHR], 0.99 [95% CI, 0.98-1.0]). However, exposed patients had a higher risk of liver cancer (aHR, 1.12 [95% CI, 1.04-1.22]) and melanoma (aHR, 1.10 [95% CI, 1.03-1.18]). We estimated a mean of 3.7 and 5.8 extra cases per year per 100 000 person-years of liver cancer and melanoma, respectively. Conclusions Our study was the largest to date to examine cancer risks associated with exposure to NDMA-contaminated valsartan. Our findings suggest a slight increased risk of liver cancer and melanoma in patients exposed to NDMA in regularly taken medications.


Assuntos
Neoplasias Hepáticas , Melanoma , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Valsartana/efeitos adversos , Dimetilnitrosamina/efeitos adversos , Contaminação de Medicamentos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/epidemiologia
2.
Br J Cancer ; 125(6): 826-838, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34316020

RESUMO

BACKGROUND: Cancer stem cells (CSCs) are related to the patient's prognosis, recurrence and therapy resistance in oesophageal squamous cell carcinoma (ESCC). Although increasing evidence suggests that aspirin (acetylsalicylic acid, ASA) could lower the incidence and improve the prognosis of ESCC, the mechanism(s) remains to be fully understood. METHODS: We investigated the role of ASA in chemotherapy/chemoprevention in human ESCC cell lines and an N-nitrosomethylbenzylamine-induced rat ESCC carcinogenesis model. The effects of combined treatment with ASA/cisplatin on ESCC cell lines were examined in vitro and in vivo. Sphere-forming cells enriched with putative CSCs (pCSCs) were used to investigate the effect of ASA in CSCs. Assay for Transposase-Accessible Chromatin with high-throughput sequencing (ATAC-seq) was performed to determine the alterations in chromatin accessibility caused by ASA in ESCC cells. RESULTS: ASA inhibits the CSC properties and enhances cisplatin treatment in human ESCC cells. ATAC-seq indicates that ASA treatment results in remarkable epigenetic alterations on chromatin in ESCC cells, especially their pCSCs, through the modification of histone acetylation levels. The epigenetic changes activate Bim expression and promote cell death in CSCs of ESCC. Furthermore, ASA prevents the carcinogenesis of NMBzA-induced ESCC in the rat model. CONCLUSIONS: ASA could be a potential chemotherapeutic adjuvant and chemopreventive drug for ESCC treatment.


Assuntos
Aspirina/administração & dosagem , Cisplatino/administração & dosagem , Neoplasias Esofágicas/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Animais , Aspirina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Dimetilnitrosamina/efeitos adversos , Dimetilnitrosamina/análogos & derivados , Sinergismo Farmacológico , Epigênese Genética/efeitos dos fármacos , Neoplasias Esofágicas/induzido quimicamente , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/induzido quimicamente , Carcinoma de Células Escamosas do Esôfago/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Ratos , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Int J Biol Macromol ; 185: 696-707, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34174316

RESUMO

The inspection of variations in the proteomic aspects conspire the biomarker discovery in diagnostics of peculiar diseases. Recent developments in high-throughput proteomic techniques have provided leverage in the discovery of biomarkers during the etiology of various diseases. We identified potential biomarkers by utilizing proteomics, bioinformatics and gene expression studies. Meticulous assessment of collagen and hydroxyproline levels along with the glycogen and protein carbonyl levels exhibited deterioration in the N' - Nitrosodiethylamine (NDEA) administered rat livers and subsequent salubrious effect of pomegranate juice. The immunohistochemical inspection of iNOS and nitrite estimation indicated the peccant fibrotic alterations. 2D proteome profiling and MALDI-TOF MS/MS furthered the significant biomarkers to be analyzed for the gene ontology by PANTHER, cluster analysis by DAVID and network simulation by STRING 10.0. Several genes found relevant after MALDI analysis were evaluated by real-time PCR (RTPCR). Our data revealed CYP2b15, HSP70, TRFE, HPT, Il1rl2, Ric8a, Krt18, Hsp90b1 and iNOS as novel biomarkers for the mechanism of pomegranate against liver fibrosis. It can be inferred that NDEA-induced liver fibrosis actuates various biological pathways by the identified biomarkers and pomegranate juice modifies them.


Assuntos
Biomarcadores/metabolismo , Dimetilnitrosamina/efeitos adversos , Cirrose Hepática/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Punica granatum/química , Animais , Suplementos Nutricionais , Modelos Animais de Doenças , Sucos de Frutas e Vegetais , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Queratina-18/genética , Queratina-18/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/metabolismo , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Extratos Vegetais/farmacologia , Proteômica , Ratos , Receptores de Interleucina/genética , Receptores de Interleucina/metabolismo , Espectrometria de Massas em Tandem
4.
Environ Mol Mutagen ; 62(5): 288-292, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33963777

RESUMO

Exposure to N-nitrosodimethylamine (NDMA) has recently been linked to a childhood cancer cluster in Wilmington, MA, which is home to the Olin Chemical Superfund Site. When it was discovered in the 1990's that 22 children in a town of under 22,000 people got cancer, the community took action and pressed for an investigation into the possibility that chemicals from the Olin Chemical site had contaminated their water. This led to the eventual discovery that NDMA was present in the town water supply. NDMA has long been known for its potent carcinogenicity in animal models, and so the community pointed to NDMA as a possible cause. This led to an investigation by the Massachusetts Department of Public Health, which, in 2021, released its findings showing an association between NDMA exposure in utero and childhood cancer. The mission of the NIEHS Superfund Research Program is to protect human health from hazardous substances. In 2017, in response to community concerns, a team at MIT created the MIT Superfund Research Program Center with a focus on research related to NDMA. Just 1 week prior to the release of the Department of Public Health study, the MIT Superfund Research Program Center published a manuscript in Cell Reports that identifies the Alkyladenine DNA glycosylase (AAG) as a possible genetic susceptibility factor. This commentary provides an author's perspective on the context and implications of this and related research.


Assuntos
Dimetilnitrosamina/efeitos adversos , Exposição Materna/efeitos adversos , Neoplasias/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Poluentes Químicos da Água/efeitos adversos , Criança , Feminino , Humanos , Massachusetts/epidemiologia , Neoplasias/induzido quimicamente , Neoplasias/patologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/patologia
5.
Nutrients ; 14(1)2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-35010924

RESUMO

Non-alcoholic steatohepatitis (NASH) can cause liver cirrhosis and hepatocellular carcinoma (HCC), with cases increasing worldwide. To reduce the incidence of liver cirrhosis and HCC, NASH is targeted for the development of treatments, along with viral hepatitis and alcoholic hepatitis. Lactoferrin (LF) has antioxidant, anti-cancer, and anti-inflammatory activities. However, whether LF affects NASH and fibrosis remains unelucidated. We aimed to clarify the chemopreventive effect of LF on NASH progression. We used a NASH model with metabolic syndrome established using connexin 32 (Cx32) dominant negative transgenic (Cx32ΔTg) rats. Cx32ΔTg rats (7 weeks old) were fed a high-fat diet and intraperitoneally injected with dimethylnitrosamine (DMN). Rats were divided into three groups for LF treatment at 0, 100, or 500 mg/kg/day for 17 weeks. Lactoferrin significantly protected steatosis and lobular inflammation in Cx32ΔTg rat livers and attenuated bridging fibrosis or liver cirrhosis induced by DMN. By quantitative RT-PCR, LF significantly down-regulated inflammatory (Tnf-α, Il-6, Il-18, and Il-1ß) and fibrosis-related (Tgf-ß1, Timp2, and Col1a1) cytokine mRNAs. Phosphorylated nuclear factor (NF)-κB protein decreased in response to LF, while phosphorylated JNK protein was unaffected. These results indicate that LF might act as a chemopreventive agent to prevent hepatic injury, inflammation, and fibrosis in NASH via NF-κB inactivation.


Assuntos
Lactoferrina/farmacologia , Cirrose Hepática/prevenção & controle , NF-kappa B/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Animais , Anticarcinógenos/farmacologia , Carcinogênese/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Conexinas/metabolismo , Citocinas/metabolismo , Dimetilnitrosamina/efeitos adversos , Fibrose/prevenção & controle , Lactoferrina/administração & dosagem , Fígado/lesões , Neoplasias Hepáticas/tratamento farmacológico , Masculino , Hepatopatia Gordurosa não Alcoólica/metabolismo , Ratos , Fator de Crescimento Transformador beta1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
6.
J Mol Med (Berl) ; 98(9): 1203-1213, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32666246

RESUMO

Hepatic fibrosis and cirrhosis are chronic diseases affecting liver and a major health problem throughout the world. The hallmark of fibrosis and cirrhosis is inordinate synthesis and deposition of fibril forming collagens in the extracellular matrix of the liver leading to nodule formation and loss of normal architecture. Hepatic stellate cells play a crucial role in the pathogenesis and progression of liver fibrosis through secretion of several potent fibrogenic factors that trigger hepatocytes, portal fibrocytes, and bone marrow-derived fibroblasts to synthesize and deposit several connective tissue proteins, especially collagens between hepatocytes and space of Disse. Regulation of various events involved in the activation and transformation of hepatic stellate cells seems to be an appropriate strategy for the arrest of hepatic fibrosis and liver cirrhosis. In order to unravel the molecular mechanisms involved in the pathogenesis and progression of hepatic fibrosis, to determine proper and potent targets to arrest fibrosis, and to discover powerful therapeutic agents, a quick and reproducible animal model of hepatic fibrosis and liver cirrhosis that display all decompensating features of human condition is required. This review thoroughly evaluates the biochemical, histological, and pathological features of N-nitrosodimethylamine-induced model of liver injury, hepatic fibrosis, and early cirrhosis in rodents.


Assuntos
Dimetilnitrosamina/efeitos adversos , Cirrose Hepática/etiologia , Cirrose Hepática/metabolismo , Substâncias Macromoleculares/metabolismo , Animais , Modelos Animais de Doenças , Suscetibilidade a Doenças , Fibroblastos , Fibrose , Células Estreladas do Fígado/metabolismo , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Cirrose Hepática/patologia , Metilação , Roedores
8.
Clin Transl Sci ; 13(4): 649-651, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32107850

RESUMO

Ranitidine has been the topic of recent media reports. Current findings, confirmed by the US Food and Drug Administration, indicate that some ranitidine products contain a substance that may be carcinogenic. Providers and patients require additional information on the risks of continuing therapy vs. the benefits of the medication. This article comments on what is currently known about the evolving situation of elevated N-nitrosodimethylamine levels in ranitidine and the limits of the existing information to assess best practices.


Assuntos
Dimetilnitrosamina/efeitos adversos , Contaminação de Medicamentos , Refluxo Gastroesofágico/tratamento farmacológico , Meios de Comunicação de Massa , Ranitidina/efeitos adversos , Carcinogênese/induzido quimicamente , Recall de Medicamento , Estabilidade de Medicamentos , Humanos , Disseminação de Informação , Neoplasias/induzido quimicamente , Neoplasias/prevenção & controle , Ranitidina/química , Ranitidina/normas , Estados Unidos , United States Food and Drug Administration/normas
9.
Ecotoxicol Environ Saf ; 170: 412-417, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30550972

RESUMO

In this study, a health risk assessment of N-nitrosodimethylamine (NDMA) in drinking water and food was conducted using disability-adjusted life years (DALYs) in major cities of China. Considering the numerous non-detected values found in drinking water samples, a zero-inflated model was employed to obtain a more precise NDMA concentration distribution function in drinking water. With exogenous chronic daily intake of 1.20 × 10-6 mg/(kg*d), the lifetime cancer risk and disability-adjusted life years of NDMA are 4.01 × 10-5 and 5.52 × 10-6 per person-year (ppy). The disease burden attributable to water sources accounts for nearly 9.94% of total exogenous intake. The contribution rate of vegetables is the largest, followed by cereals, milk products, fish and shrimp, and meat. Taking endogenous sources into consideration, the contribution rates of drinking water and food sources decrease to 0.08% and 0.69%. This study provides a scientific basis for making policy decisions on NDMA pollution management.


Assuntos
Dimetilnitrosamina/análise , Água Potável/análise , Contaminação de Alimentos/análise , Anos de Vida Ajustados por Qualidade de Vida , China , Cidades , Dimetilnitrosamina/efeitos adversos , Análise de Alimentos , Humanos , Modelos Teóricos , Neoplasias/induzido quimicamente , Neoplasias/diagnóstico , Medição de Risco , Fatores de Risco
10.
BMJ ; 362: k3851, 2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-30209057

RESUMO

OBJECTIVE: To perform an expedited assessment of cancer risk associated with exposure to N-nitrosodimethylamine (NDMA) through contaminated valsartan products. DESIGN: Nationwide cohort study. SETTING: Danish health registries on individual level prescription drug use, cancer occurrence, and hospital diagnoses. PARTICIPANTS: 5150 Danish patients with no history of cancer, aged 40 years or older, and using valsartan at 1 January 2012 or initiating use between 1 January 2012 and 30 June 2017. Participants were followed from one year after cohort entry (lag time period) until experiencing a cancer outcome, death, migration, or end of study period (30 June 2018). Each participant's exposure to NDMA (ever exposure and predefined categories of cumulative valsartan exposure) was mapped out as a time varying variable while also applying a one year lag. MAIN OUTCOME MEASURES: Association between NDMA exposure and a primary composite endpoint comprising all cancers except non-melanoma skin cancer, estimated using Cox regression. In supplementary analyses, the risk of individual cancers was determined. RESULTS: The final cohort comprised 5150 people followed for a median of 4.6 years. In total, 3625 cohort participants contributed 7344 person years classified as unexposed to NDMA, and 3450 participants contributed 11 920 person years classified as ever exposed to NDMA. With 104 cancer outcomes among NDMA unexposed participants and 198 among exposed participants, the adjusted hazard ratio for overall cancer was 1.09 (95% confidence interval 0.85 to 1.41), with no evidence of a dose-response relation (P=0.70). For single cancer outcomes, increases in risk were observed for colorectal cancer (hazard ratio 1.46, 95% confidence interval 0.79 to 2.73) and for uterine cancer (1.81, 0.55 to 5.90), although with wide confidence intervals that included the null. CONCLUSIONS: The results do not imply a markedly increased short term overall risk of cancer in users of valsartan contaminated with NDMA. However, uncertainty persists about single cancer outcomes, and studies with longer follow-up are needed to assess long term cancer risk.


Assuntos
Dimetilnitrosamina/efeitos adversos , Contaminação de Medicamentos/estatística & dados numéricos , Neoplasias/induzido quimicamente , Valsartana/efeitos adversos , Adulto , Idoso , Bloqueadores do Receptor Tipo 1 de Angiotensina II/efeitos adversos , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Estudos de Coortes , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/epidemiologia , Dinamarca/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Fatores de Risco , Neoplasias Uterinas/induzido quimicamente , Neoplasias Uterinas/epidemiologia , Valsartana/uso terapêutico
11.
Drug Dev Res ; 78(3-4): 155-163, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28524372

RESUMO

Preclinical Research Baogan Yihao (BGYH) is a traditional Chinese herbal medicine for the treatment of chronic liver diseases. In this study, the effects of BGYH on dimethylnitrosamine (DMN)-induced liver fibrosis were investigated using a rat model. BGYH alleviate liver damage, as indicated by decreased levels of AST, ALT, γ-GT, and AKP. BGYH also prevented collagen deposition and reduced pathological tissue injury in liver tissue. In fibrosis, high levels of α-SMA and TGF-ß in liver tissue were markedly attenuated by BGYH. The inhibitory effect of BGYH on HSC-T6 proliferation demonstrated that BGYH exhibited significant hepatoprotective and antifibrogenic effects on DMN-induced liver injury. These findings suggest that BGYH may have therapeutic potential in the prevention and therapy of liver fibrosis. Drug Dev Res 78 : 155-163, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Dimetilnitrosamina/efeitos adversos , Medicamentos de Ervas Chinesas/administração & dosagem , Actinas/metabolismo , Animais , Linhagem Celular , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Fator de Crescimento Transformador beta/metabolismo
12.
J Biomol Struct Dyn ; 35(5): 1020-1029, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26982119

RESUMO

In our study, renal cancer is induced in rats making use of dimethylnitrosamine (DMN). G1 - Group 1 were control rats and G2 - Group 2 rats were given a single intra-peritoneal injection of DMN of 50 mg/kg body weight resulting in 100% incidences of renal tumors after 12 months. SEM and histopathology confirmed the presence of renal cancer in the DMN-treated rats. Making use of ammonium sulfate precipitation and gel filtration chromatography on Sephacryl S-100HR column, a thiol protease inhibitor was isolated from kidney of control rats known as Rat kidney Cystatin (RKC) as well as from kidney of cancerous rat called as Cancerous Rat Kidney Cystatin (CRKC). Both these inhibitors were characterized, and interestingly, it was found that CRKC showed greater anti-papain activity and also it was stable in a broad pH and temperature range thus implying that CRKC is more stable as compared to RKC. UV and fluorescence spectroscopy point out in structural difference between RKC and CRKC which was further confirmed by Circular dichroism (CD) and FTIR spectroscopy. Our study clearly showed that kidney cystatin is structurally modified in the case of renal cancer and performs its role in a more efficacious manner.


Assuntos
Cistatinas/química , Animais , Biomarcadores Tumorais , Biópsia , Dicroísmo Circular , Cistatinas/metabolismo , Dimetilnitrosamina/efeitos adversos , Concentração de Íons de Hidrogênio , Neoplasias Renais/induzido quimicamente , Neoplasias Renais/diagnóstico , Neoplasias Renais/metabolismo , Neoplasias Renais/ultraestrutura , Masculino , Prognóstico , Estabilidade Proteica , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Relação Estrutura-Atividade , Termodinâmica
13.
Mol Carcinog ; 55(11): 1867-1875, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27696538

RESUMO

Aberrant methylation of DNA is a common event in the development of cancers, including squamous cell carcinoma (SCC) of the human esophagus. In the present study, we determined: (a) whether aberrant DNA methylation also occurs in the development of N-nitrosomethylbenzylamine (NMBA)-induced tumorigenesis in the rat esophagus, a model of human esophageal SCC; and (b) if so, whether dietary black raspberries (BRBs) are capable of preventing this aberrant DNA methylation. A diet containing 5% BRBs inhibited the development of NMBA-induced tumors in the rat esophagus. This inhibition was associated with reduced mRNA levels of the DNA methyltransferases, Dnmt1 and Dnmt3b, in both dysplastic lesions and in papillomas of the esophagus. In addition, promoter methylation of Sfrp4, a WNT pathway antagonist, was significantly reduced by the berry diet, and this was associated with decreased nuclear localization of ß-CATENIN and reduced expression of c-MYC protein in NMBA-treated esophagi. Decreased promoter methylation of Sfrp4 correlated with decreased expression of Dmnt3b and, ultimately, with increased Sfrp4 mRNA expression. This suggests that epigenetic alterations in NMBA-induced rat esophageal tumorigenesis recapitulate epigenetic events in human esophageal SCC, and that BRBs could be useful in preventing the aberrant DNA methylation involved in the development of human esophageal SCC. © 2015 Wiley Periodicals, Inc.


Assuntos
Carcinoma de Células Escamosas/dietoterapia , DNA (Citosina-5-)-Metiltransferases/genética , Dimetilnitrosamina/análogos & derivados , Neoplasias Esofágicas/dietoterapia , Extratos Vegetais/administração & dosagem , Proteínas Proto-Oncogênicas/genética , Rubus/química , Animais , Carcinoma de Células Escamosas/induzido quimicamente , Carcinoma de Células Escamosas/genética , DNA (Citosina-5-)-Metiltransferase 1 , Metilação de DNA/efeitos dos fármacos , Dimetilnitrosamina/efeitos adversos , Epigênese Genética/efeitos dos fármacos , Neoplasias Esofágicas/induzido quimicamente , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Extratos Vegetais/farmacologia , Ratos , Via de Sinalização Wnt/efeitos dos fármacos
14.
Sci Rep ; 6: 33593, 2016 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-27646469

RESUMO

Liver fibrosis is a wound-healing response characterized with the accumulation of extracellular matrix (ECM). And hepatic stellate cells (HSCs) are the principal cell source of ECM. NR4A2 (Nurr1) is a member of orphan nuclear receptor NR4A family and acts as transcription factor. It participates in regulating cell differentiation, proliferation and apoptosis. We previously demonstrated that NR4A2 expression in fibrotic liver reduced significantly compared with normal liver and NR4A2 knockout in HSCs promoted ECM production. In the present study we explored the role of NR4A2 on liver fibrosis. Studies in cultured HSCs demonstrated that NR4A2 over-expression suppressed the activation of HSCs, such as ECM production and invasion ability. Moreover cell cycle was arrested, cell apoptosis was promoted and cell signaling pathway was influenced. Adenovirus-mediated delivery of NR4A2 in rats ameliorated significantly dimethylnitrosamine (DMN) induced liver fibrosis. The In vivo experiments produced results consistent with in vitro experiments. Taken together these results demonstrate NR4A2 enhancement attenuates liver fibrosis via suppressing the activation of HSCs and NR4A2 may be an ideal target for anti-fibrotic therapy.


Assuntos
Adenoviridae/genética , Expressão Gênica , Vetores Genéticos/genética , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/genética , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Transdução Genética , Transporte Ativo do Núcleo Celular , Animais , Apoptose/genética , Pontos de Checagem do Ciclo Celular/genética , Movimento Celular/genética , Proliferação de Células , Dimetilnitrosamina/efeitos adversos , Modelos Animais de Doenças , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Terapia Genética , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Cirrose Hepática/terapia , Masculino , Proteína Quinase 1 Ativada por Mitógeno , Proteína Quinase 3 Ativada por Mitógeno , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Fosforilação , Ratos
15.
Zhonghua Liu Xing Bing Xue Za Zhi ; 37(5): 725-9, 2016 May.
Artigo em Chinês | MEDLINE | ID: mdl-27188372

RESUMO

OBJECTIVE: To analyze the relationship between N-nitrosodimethylamine(NDMA)and the risk of digestive tract cancers. METHODS: The papers about the relationship between NDMA and the risk of digestive tract cancers published from 1980 to 2012 were retrieved following databases: Chinese BioMedical Literature Database(CBM), the Chinese Journal Full-text Database(CNKI), Wanfang Database, PubMed and EBSCO. The fix and random effect model was used and statistical analyses were conducted by using RevMan 5.1 software. RESULTS: Thirteen papers were found, in which 7 about digestive tract cancers were used in this Meta analysis. The NDMA had significant positive effect on the incidence of digestive tract cancers(RR=1.12, 95% CI: 1.03-1.21). The relationship between NDMA and esophageal cancer was not significant(RR=1.18, 95%CI: 0.98-1.41)but NDMA could increase the risk of gastric cancer(RR=1.08, 95% CI: 1.00-1.18). For the subtypes of esophageal and gastric cancer, NDMA had positive relationship with esophageal squamous cell carcinoma(RR=1.72, 95% CI: 1.01-2.96), but had no significant relationship with esophageal adenocarcinoma, cardiac carcinoma and gastric adenocarcinoma. CONCLUSION: The population-based cohort studies have showed that the NDMA could significantly increase the risk of digestive tract cancers, but the effects differed with subtypes of esophageal and gastric cancer. However, it is necessary to collect more evidence due to the limited studies and obvious differences in the study design, sampling and exposure measurement of these cohort studies.


Assuntos
Povo Asiático/estatística & dados numéricos , Neoplasias do Sistema Digestório/induzido quimicamente , Dimetilnitrosamina/efeitos adversos , Neoplasias Gastrointestinais/induzido quimicamente , Adenocarcinoma , Carcinoma de Células Escamosas/induzido quimicamente , Carcinoma de Células Escamosas/epidemiologia , China/epidemiologia , Estudos de Coortes , Neoplasias do Sistema Digestório/etiologia , Dimetilnitrosamina/administração & dosagem , Neoplasias Esofágicas/induzido quimicamente , Neoplasias Esofágicas/epidemiologia , Carcinoma de Células Escamosas do Esôfago , Neoplasias Gastrointestinais/epidemiologia , Humanos , Incidência , Vigilância da População , Medição de Risco , Fatores de Risco , Neoplasias Gástricas/induzido quimicamente
16.
PLoS Negl Trop Dis ; 9(8): e0004008, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26313366

RESUMO

BACKGROUND: Clonorchis sinensis is a group-I bio-carcinogen for cholangiocarcinoma (CCA). Although the epidemiological evidence links clonorchiasis and CCA, the underlying molecular mechanism involved in this process is poorly understood. In the present study, we investigated expression of oncogenes and tumor suppressors, including PSMD10, CDK4, p53 and RB in C. sinensis induced hamster CCA model. METHODS: Different histochemical/immunohistochemical techniques were performed to detect CCA in 4 groups of hamsters: uninfected control (Ctrl.), infected with C. sinensis (Cs), ingested N-nitrosodimethylamine (NDMA), and both Cs infected and NDMA introduced (Cs+NDMA). The liver tissues from all groups were analyzed for gene/protein expressions by quantitative PCR (qPCR) and western blotting. PRINCIPAL FINDINGS: CCA was observed in all hamsters of Cs+NDMA group with well, moderate, and poorly differentiated types measured in 21.8% ± 1.5%, 13.3% ± 1.3%, and 10.8% ± 1.3% of total tissue section areas respectively. All CCA differentiations progressed in a time dependent manner, starting from the 8th week of infection. CCA stroma was characterized with increased collagen type I, mucin, and proliferative cell nuclear antigen (PCNA). The qPCR analysis showed PSMD10, CDK4 and p16INK4 were over-expressed, whereas p53 was under-expressed in the Cs+NDMA group. We observed no change in RB1 at mRNA level but found significant down-regulation of RB protein. The apoptosis related genes, BAX and caspase 9 were found downregulated in the CCA tissue. Gene/protein expressions were matched well with the pathological changes of different groups except the NDMA group. Though the hamsters in the NDMA group showed no marked pathological lesions, we observed over-expression of Akt/PKB and p53 genes proposing molecular interplay in this group which might be related to the CCA initiation in this animal model. CONCLUSIONS/SIGNIFICANCE: The present findings suggest that oncogenes, PSMD10 and CDK4, and tumor suppressors, p53 and RB, are involved in the carcinogenesis process of C. sinensis induced CCA in hamsters.


Assuntos
Colangiocarcinoma/metabolismo , Clonorquíase/metabolismo , Clonorchis sinensis/fisiologia , Quinase 4 Dependente de Ciclina/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteína do Retinoblastoma/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Colangiocarcinoma/induzido quimicamente , Colangiocarcinoma/genética , Colangiocarcinoma/parasitologia , Clonorquíase/genética , Clonorquíase/parasitologia , Cricetinae , Quinase 4 Dependente de Ciclina/genética , Dimetilnitrosamina/efeitos adversos , Modelos Animais de Doenças , Humanos , Masculino , Mesocricetus , Complexo de Endopeptidases do Proteassoma/genética , Proteína do Retinoblastoma/genética , Proteína Supressora de Tumor p53/genética
17.
PLoS One ; 10(7): e0131560, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26147856

RESUMO

Rhizoma Paridis Saponins (RPS), a natural compound purified from Rhizoma Paridis, has been found to inhibit cancer growth in vitro and in animal models of cancer. However, its effects on esophageal cancer remain unexplored. The purpose of this study was to investigate the effects of RPS on tumor growth in a rat model of esophageal cancer and the molecular mechanism underlying the effects. A rat model of esophageal cancer was established by subcutaneous injection of N-nitrosomethylbenzylamine (NMBA, 1 mg/kg) for 10 weeks. RPS (350 mg/kg or 100 mg/kg) was administered by oral gavage once daily for 24 weeks starting at the first NMBA injection. RPS significantly reduced the size and number of tumors in the esophagus of rats exposed to NMBA and inhibited the viability, migration, and invasion of esophageal cancer cells EC9706 and KYSE150 in a dose dependent manner (all P < 0.01). Flow cytometry revealed that RPS induced apoptosis and cell cycle G2/M arrest in the esophageal cancer cells. The expression of cyclooxygenases-2 (COX-2) and Cyclin D1 in rat esophageal tissues and the esophageal cancer cells were also significantly reduced by RPS (all P < 0.01). Consistently, RPS also significantly decreased the release of prostaglandin E2, a downstream molecule of COX-2, in a dose-dependent manner (P < 0.01). Our study suggests that RPS inhibit esophageal cancer development by promoting apoptosis and cell cycle arrest and inhibiting the COX-2 pathway. RPS might be a promising therapeutic agent for esophageal cancer.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Dimetilnitrosamina/análogos & derivados , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/metabolismo , Extratos Vegetais/farmacologia , Rizoma/química , Saponinas/farmacologia , Animais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclina D1/metabolismo , Dimetilnitrosamina/efeitos adversos , Dinoprostona/metabolismo , Neoplasias Esofágicas/induzido quimicamente , Neoplasias Esofágicas/patologia , Esôfago/efeitos dos fármacos , Esôfago/metabolismo , Esôfago/patologia , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Masculino , Extratos Vegetais/química , Ratos , Ratos Endogâmicos F344 , Saponinas/química
18.
BMC Complement Altern Med ; 14: 363, 2014 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-25262005

RESUMO

BACKGROUND: ß-sitosterol is a cholesterol-like phytosterol, which widely distributed in the plant kingdom. Here, anti-fibrotic effect of the ß-sitosterol was studied using the activated human hepatic stellate cell (HSC) model and dimethylnitrosamine (DMN)-induced mouse hepatic fibrosis model. METHOD: HSCs were activated by transforming growth factor-ß (TGF-ß) and the collagen-1 and α-smooth muscle actin (α-SMA) expressions were measured at the mRNA and protein level. We also studied the effect ß-sitosterol using DMN-induced mouse hepatic fibrosis model. We then measured the collagen-1 and α-SMA expression levels in vivo to investigate anti-hepatofibrotic effect of ß-sitosterol, at both of the mRNA and protein level. RESULTS: ß-sitosterol down regulated the mRNA and protein expression levels of collagen-1 and α-SMA in activated HSC. Oral administration of the ß-sitosterol successfully alleviated the DMN-induced mouse liver damage and prevented collagen accumulation. The mRNA and protein expression levels of collagen-1 and α-SMA were also down regulated in ß-sitosterol treated mouse group. CONCLUSIONS: This study shows the effect of ß-sitosterol on the TGF-ß -or DMN-induced hepatofibrosis. Hence, we demonstrate the ß-sitosterol as a potential therapeutic agent for the hepatofibrosis.


Assuntos
Artemisia/química , Células Estreladas do Fígado/efeitos dos fármacos , Cirrose Hepática/metabolismo , Extratos Vegetais/farmacologia , Sitosteroides/farmacologia , Actinas/análise , Actinas/genética , Actinas/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Colágeno Tipo I/análise , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Dimetilnitrosamina/efeitos adversos , Expressão Gênica/efeitos dos fármacos , Humanos , Cirrose Hepática/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/química , Sitosteroides/química
19.
Food Funct ; 5(11): 2883-91, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25183344

RESUMO

Garcinol, a polyisoprenylated benzophenone derivative, mainly isolated from Garcinia indica fruit rind, has been suggested to exhibit many biological benefits including antioxidative, anti-inflammatory, and anti-tumor activities. The aim of this study is to evaluate the protective effects of garcinol on dimethylnitrosamine (DMN)-induced liver fibrosis in rats. The administration of DMN for six consecutive weeks resulted in the decrease of body weights, the elevation of serum aminotransferases, as well as histological lesions in livers. However, oral administration of garcinol remarkably inhibited the elevation of aspartate transaminase (AST) and relieved liver damage induced by DMN. Furthermore, our results revealed that garcinol not only effectively reduced the accumulation of extracellular matrix (ECM) components but also inhibited the expression of α-smooth muscle actin (α-SMA) in livers. The expression of transforming growth factor-ß1 (TGF-ß1) and the phosphorylation of Smad 2 and Smad 3 were also suppressed by garcinol supplementation. In conclusion, our current study suggested that garcinol exerted hepatoprotective and anti-fibrotic effects against DMN-induced liver injury in rats.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Dimetilnitrosamina/efeitos adversos , Cirrose Hepática/tratamento farmacológico , Terpenos/farmacologia , Animais , Aspartato Aminotransferases/metabolismo , Frutas/química , Garcinia/química , Fígado/efeitos dos fármacos , Fígado/metabolismo , Cirrose Hepática/induzido quimicamente , Masculino , Fosforilação , Ratos , Ratos Sprague-Dawley , Proteína Smad2/genética , Proteína Smad2/metabolismo , Proteína Smad3/genética , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
20.
Zhongguo Zhong Yao Za Zhi ; 39(8): 1473-8, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-25039185

RESUMO

OBJECTIVE: To discuss the reverse effect of Yinchenhao decoction(YCHD) in dimethyl nitrosamine (DMN)-induced hepatic fibrosis in rats. METHOD: The rat hepatic fibrosis model was established through the intraperitoneal injection with 1% dimethyl nitrosamine (DMN) with a dose of 1.0 mL x kg(-1) x d(-1) for consecutively three weeks, once for the first three days of each. The rats were randomly divided into six groups: the silymarin positive control group (50.0 mg x kg(-1) x d(-1), YCHD high (20.0 g x kg(-1) d(-1)), middle (8.0 g x kg(-1) x d(-1)) and low (3.2 g x kg(-1) x d(-1)) dose groups, the model group and the normal control group. The model group and the normal control group were orally administered with normal saline for consecutively five weeks. The pathologic changes in liver tissues were observed by HE staining. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), g-glutamyltransferase (g-GGT), hyaluronic acid (HA), laminin (LN), collagen type IV (CIV) and type III procollagen amino terminal peptide (PIIINP) in serum were determined. The metabolite profiling of amino acid and the content of hydroxyproline in liver tissues were also measured. RESULT: Compared with the model group, YCHD high and middle dose groups could significantly reverse the pathologic changes in liver tissues of rats. YCHD could reduce the levels of ALT, AST, gamma-GGT, HA, LN, CIV, PIIINP in serum and the content of hydroxyproline in liver tissues in a dose-dependent manner, and altered the metabolite profiling of amino acid in rat liver tissues. CONCLUSION: YCHD has the effect in reversing dimethyl nitrosamine induced hepatic fibrosis in rats.


Assuntos
Medicamentos de Ervas Chinesas/administração & dosagem , Cirrose Hepática/tratamento farmacológico , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Colágeno Tipo IV/metabolismo , Dimetilnitrosamina/efeitos adversos , Humanos , Hidroxiprolina/metabolismo , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/enzimologia , Masculino , Ratos , Ratos Sprague-Dawley
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