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1.
Carbohydr Polym ; 327: 121702, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38171666

RESUMO

The chain structure of starch affects its interaction with polyphenol molecules which in turn determines the nutritional function of starch. In this study, starch with different amylose content including waxy maize starch (WMS), normal maize starch (NMS) and G50 high-amylose maize starch (G50) were selected to complex with resveratrol (RA) in high-pressure homogenization (HPH) environment, and structural changes of the complexes, together with their effects on in vitro digestibility and gut microbiota were discussed. The results showed that with increasing amylose content, RA could form more inclusion complex with starch through non-covalent bonds accompanied by the increased single helix structure, V-type crystalline structure, compact nano-aggregates and total ordered structure content, which thus endowed the complex lower digestibility and intestinal probiotic function. Notably, when RA addition reached 3 %, the resistant starch (RS) content of HP-G50-3 % rose to 29.2 %, correspondingly increased the relative abundance of beneficial gut microbiota such as Megamonas and Bifidobacterium, as well as the total short-chain fatty acids (SCFAs) content. Correlation analysis showed that V-type crystalline structure positively correlated with the growth of Pediococcu and Blautia (p < 0.05) for producing SCFAs. These findings provided feasible ideas for the development of personalized nutritional starch-based foods.


Assuntos
Amilose , Microbioma Gastrointestinal , Humanos , Amilose/química , Zea mays/química , Resveratrol , Amido/química , Amilopectina/química , Ácidos Graxos Voláteis
2.
Eur J Pharmacol ; 931: 175216, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35988787

RESUMO

Deregulation of protein post-translational modifications is intensively involved in the etiology of diseases, including degenerative diseases, inflammatory injuries, and cancers. Acetylation is one of the most common post-translational modifications of proteins, and the acetylation levels are controlled by two mutually antagonistic enzyme families, histone acetyl transferases (HATs) and histone deacetylases (HDACs). HATs loosen the chromatin structure by neutralizing the positive charge of lysine residues of histones; whereas HDACs deacetylate certain histones, thus inhibiting gene transcription. Compared with HATs, HDACs have been more intensively studied, particularly regarding their clinical significance. HDACs extensively participate in the regulation of proliferation, migration, angiogenesis, immune escape, and therapeutic resistance of cancer cells, thus emerging as critical targets for clinical cancer therapy. Compared to HATs, inhibitors of HDAC have been clinically used for cancer treatment. Here, we enumerate and integratethe mechanisms of HDAC family members in tumorigenesis and cancer progression, and address the new and exciting therapeutic implications of single or combined HDAC inhibitor (HDACi) treatment.


Assuntos
Histona Desacetilases , Neoplasias , Acetilação , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Histona Desacetilases/metabolismo , Histonas/metabolismo , Humanos , Neoplasias/tratamento farmacológico
3.
J Nutr Sci Vitaminol (Tokyo) ; 65(1): 72-81, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30814415

RESUMO

This meta-analysis aimed to explore the association between anthocyanins intake and the risk of gastric cancer. All the relative articles have been searched in the online databases, including PubMed, EMBASE, Web of Science, and the Cochrane Library until June 11th, 2018. Risk ratios (RRs) or odds ratio (ORs) and their 95% confidence intervals were calculated and pooled through the STATA 12.0. A total of 6 studies were finally selected in the meta-analysis. No significant association was found between total anthocyanins consumption and gastric cancer risk (RR=0.92, 95%CI: 0.81-1.04). Likewise, there was also no significant evidence of the relationship between anthocyanins intake and gastric cancer in tumor site (cardia: RR=0.90, 95%CI: 0.62-1.31; noncardia: RR=0.86, 95%CI: 0.69-1.07) and gender (men: RR=1.02, 95%CI: 0.73-1.40; women: RR=0.80, 95%CI: 0.52-1.23). The dose-response relationship was also not found in this meta-analysis. The Grades of Recommendations Assessment, Development and Evaluation (GRADE) quality in our study was very low. The results of our meta-analysis suggested the intake of anthocyanins had no association with the risk of gastric cancer and further studies are needed.


Assuntos
Antocianinas/efeitos adversos , Dieta/efeitos adversos , Neoplasias Gástricas/etiologia , Estudos de Casos e Controles , Estudos de Coortes , Ingestão de Energia , Feminino , Humanos , Masculino , Fatores de Risco
4.
Environ Geochem Health ; 41(1): 43-52, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29948534

RESUMO

Cadmium (Cd)-contaminated rice (Oryza sativa) in Southern China is a great threat to food security, and the paddy soil remediation is urgently needed to reduce Cd accumulation in rice. Application of biochar could effectively immobilize soil Cd and reduce Cd uptake by rice. Fields that were applied with soil treatments including control and 15 and 30 t ha-1 each hickory nut shell-derived biochar (KC) or maize straw-derived biochar (MC), and grown with two rice varieties (hybrid rice and late japonica rice) were selected for this study. The long-term effect of biochars on decreasing Cd bioavailability in paddy soils was evaluated. The results showed when MC was applied at 15 t ha-1, DTPA-Cd (soil cadmium extracted by diethylenetriamine pentaacetic acid) was reduced by 20.0 and 34.5% in Field A (slightly Cd pollution) and B (moderately Cd pollution), respectively. In Field B, soil DTPA-Cd concentrations with application of 30 t ha-1 biochars were all lower than that of 15 t ha-1 biochar, but there were no significant differences between the two types of biochars. Cd concentration in rice grains and straws of hybrid rice are two times more than those of late japonica rice. Cd bio-concentration factor both of grains and straw was significantly increased by biochar application, which in Field A was higher than that in Field B. Our results suggest that biochars reduce Cd accumulation in rice grains by immobilizing soil Cd. KC has a higher potential in lowering Cd bioavailability than MC. Hybrid rice should be prohibited to cultivate in these areas.


Assuntos
Cádmio/análise , Carvão Vegetal/química , Poluição Ambiental/análise , Oryza/química , Disponibilidade Biológica , China , Mineração , Estruturas Vegetais/química , Solo/química , Poluentes do Solo/análise , Tungstênio/química , Zea mays
5.
J Am Coll Nutr ; 38(5): 470-477, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30589398

RESUMO

This meta-analysis aimed to summarize the association between anthocyanin consumption and the risk of colorectal cancer. All relative articles were located on online databases, including PubMed, Embase, and the Cochrane Library as of June 11, 2018. Risk ratios (RRs) or odds ratio and their 95% confidence intervals (CIs) were calculated through the STATA 12.0 software package. A total of seven studies were included in the meta-analysis. A significant inverse association was found between total anthocyanin consumption and colorectal cancer risk (RR = 0.78; 95% CI, 0.64-0.95). Likewise, there was significant evidence of a relationship between anthocyanin intake and colorectal cancer in the colon site (RR = 0.81; 95% CI, 0.71-0.92); men (RR = 0.88; 95% CI, 0.81-0.95), and case-control studies (RR = 0.69; 95% CI, 0.60-0.78). A dose-response relationship was not found in this meta-analysis. The Grades of Recommendations Assessment, Development, and Evaluation quality in our study was very low. This meta-analysis indicates that anthocyanin consumption is inversely associated with the risk of colorectal cancer. Anthocyanins may play an active role in the prevention of colorectal cancer. Key teaching points: Some epidemiological studies found an inverse correlation between the high consumption of anthocyanins and low risk of colorectal cancer. Because of this structure, anthocyanins/anthocyanidins have a powerful capability of donating electrons, which can be characterized as antioxidant properties. Anthocyanins can also inhibit colon cancer by interfering in the cell cycle and inducing the effect of anti-proliferation and apoptosis. The formation of cytoplasmic vacuoles in cells also indicates that anthocyanins may induce autophagy. From the findings of nonrandomized controlled trials, anthocyanins may play an active role in the prevention of colorectal cancer.


Assuntos
Antocianinas/administração & dosagem , Antioxidantes/administração & dosagem , Neoplasias do Colo/prevenção & controle , Neoplasias Colorretais/prevenção & controle , Suplementos Nutricionais , Adulto , Idoso , Estudos de Casos e Controles , Neoplasias do Colo/etiologia , Neoplasias Colorretais/etiologia , Dieta/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Observacionais como Assunto , Razão de Chances , Fatores de Risco
6.
Bioorg Med Chem Lett ; 27(16): 3704-3708, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28711352

RESUMO

Our research on hydantoin based TNF-α converting enzyme (TACE) inhibitors led to fused bi-heteroaryl hydantoin series that demonstrate sub-nanomolar potency (Ki) as well as excellent activity in human whole blood (hWBA). However, lead compound 2 posed some formulation challenges which prevented it for further development. A prodrug approach was investigated to address this issue. The pivalate prodrug 3 can be formulated as stable neutral form and demonstrated improved DMPK properties when compared with parent compound.


Assuntos
Proteína ADAM17/antagonistas & inibidores , Hidantoínas/química , Hidantoínas/síntese química , Hidantoínas/farmacologia , Ácidos Pentanoicos/química , Pró-Fármacos/síntese química , Pró-Fármacos/farmacologia , Proteína ADAM17/metabolismo , Administração Oral , Animais , Área Sob a Curva , Cães , Ativação Enzimática/efeitos dos fármacos , Meia-Vida , Haplorrinos , Humanos , Hidantoínas/administração & dosagem , Hidantoínas/farmacocinética , Ácidos Pentanoicos/administração & dosagem , Ácidos Pentanoicos/farmacocinética , Pró-Fármacos/administração & dosagem , Pró-Fármacos/farmacocinética , Curva ROC , Ratos , Relação Estrutura-Atividade
7.
Inhal Toxicol ; 27(1): 64-73, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25518993

RESUMO

The mechanisms underlying hepatoxic effects of ethylbenzene still remain unknown. We investigated the toxic effects of ethylbenzene on liver and explored the mechanism of mitochondria-mediated apoptosis pathway. Forty male Sprague-Dawley rats were used as an in vivo model with ethylbenzene inhalation of 0, 433.5 mg/m(3), 4335 mg/m(3) and 6500 mg/m(3) for 13 weeks. Levels of malondialdehyde, glutathione, glutathione peroxidase and superoxide dismutase were assayed. Meanwhile, the ultrastructure of hepatic tissues was observed and cell apoptosis was detected via terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. Furthermore, we investigated the expression levels of mRNA and protein of bax, bcl-2, cytochrome c, caspase-9 and caspase-3 in rat liver tissues. Compared with control group, the malondialdehyde levels were significantly elevated while glutathione levels and activities of glutathione peroxidase and superoxide dismutase were decreased, respectively. The mitochondria of liver appeared swollen with vacuolar structure and loss of cristae in 6500 mg/m(3) ethylbenzene-treated group, and ethylbenzene induced a significant increase in the percentage of apoptotic cells as compared to the control group. In addition, enhanced mRNA and protein expression levels of all measured genes were observed in ethylbenzene-treated groups except the decreased bcl-2 expression levels. Our results indicated that ethylbenzene may induce oxidative damage and apoptosis in rat liver. Mitochondrial-mediated pathway was involved in the apoptosis process.


Assuntos
Apoptose/efeitos dos fármacos , Derivados de Benzeno/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Mitocôndrias/metabolismo , Alanina Transaminase/sangue , Animais , Apoptose/fisiologia , Aspartato Aminotransferases/sangue , Caspase 3/genética , Caspase 3/metabolismo , Caspase 9/genética , Caspase 9/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Fígado/ultraestrutura , Masculino , Malondialdeído/metabolismo , Mitocôndrias/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
8.
Artigo em Chinês | MEDLINE | ID: mdl-25511271

RESUMO

OBJECTIVE: To investigate the effect of smoking on the microRNAs (miRNAs) expression in pneumoconiosis patients. METHODS: Real-time qPCR was used to measure the expression levels of miR-21, miR-200c, miR-16, miR-204, miR-206, miR-155, let-7g, miR-30b, and miR-192 in 36 non-smoking patients with pneumoconiosis and 38 smoking patients with pneumoconiosis, and the differences in expression levels between the two groups were evaluated by two-independent samples t-test. RESULTS: The expression of miR-192 in serum showed a significant difference between non-smoking and smoking pneumoconiosis patients (P < 0.05), and it decreased gradually in smoking patients with stage I and II pneumoconiosis. In the serum of all pneumoconiosis patients, the expression level of miR-16 was the highest, while the expression level of miR-204 was the lowest. CONCLUSION: Pneumoconiosis patients have differential expression of miRNAs in serum, and smoking has an effect on the miRNAs expression in pneumoconiosis patients.


Assuntos
MicroRNAs/biossíntese , Pneumoconiose/fisiopatologia , Fumar/efeitos adversos , Humanos , Pneumoconiose/metabolismo , Reação em Cadeia da Polimerase
9.
Bioorg Med Chem Lett ; 24(4): 1085-8, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24486132

RESUMO

The structure-human CXCR3 binding affinity relationship of a series of pyridyl/pyrazinyl-piperazinyl-piperidine derivatives were explored with a focus to improve PK, hERG and metabolic profiles. Several small heterocycles were identified as amide surrogates, which minimized many potential metabolite issues. During the course of SAR development, we have observed the additive effect of desirable functional groups to improve hERG and PK profiles which lead to the discovery of many clinically developable CXCR3 antagonists with excellent overall profile.


Assuntos
Amidas/farmacologia , Descoberta de Drogas , Canais de Potássio Éter-A-Go-Go/metabolismo , Compostos Heterocíclicos/farmacologia , Receptores CXCR3/antagonistas & inibidores , Amidas/administração & dosagem , Amidas/química , Animais , Relação Dose-Resposta a Droga , Compostos Heterocíclicos/administração & dosagem , Compostos Heterocíclicos/química , Humanos , Estrutura Molecular , Ratos , Relação Estrutura-Atividade
12.
Artigo em Chinês | MEDLINE | ID: mdl-23662359

RESUMO

OBJECTIVE: To study the oxidative damage and apoptosis of renal tubular epithelial cells (NRK-52e cell line) induced by ethylbenzene. METHODS: NRK-52e cells were exposed to 30, 60, 90, 120 µmol/L ethylbenzene for 24 hours. Cell viability were measured using MTT, the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), the contents of malondialdehyde (MDA) and glutathione (GSH) were detected respectively. PI fluorescent staining assay was applied to detect percentage of apoptosis in ethylbenzene-treated groups. RESULTS: Compared with control group, cell outline became clear, cell diopter increased, cell became smaller and shrinkage, some cells broke in 60 µmol/L ethylbenzene-treated group. Plenty of cells died, suspension cells increased significantly in 90 µmol/L ethylbenzene-treated group. Compared with control group, cell viability the activities of SOD and CAT and the content of GSH were significantly decreased in 60 and 90 µmol/L ethylbenzene-treated groups (P<0.05). The MDA content were remarkably elevated in 90 µmol/L ethylbenzene-treated groups (P<0.05). CONCLUSION: Ethylbenzene can induce oxidative stress and apoptosis in NRK-52e cells (P<0.05).


Assuntos
Apoptose/efeitos dos fármacos , Derivados de Benzeno/toxicidade , Células Epiteliais/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Linhagem Celular , Células Epiteliais/metabolismo , Túbulos Renais/citologia , Oxirredução , Ratos , Espécies Reativas de Oxigênio/metabolismo
13.
Bioorg Med Chem Lett ; 20(24): 7283-7, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21106451

RESUMO

Our research on hydantoin based TNF-α converting enzyme (TACE) inhibitors has led to an acetylene containing series that demonstrates sub-nanomolar potency (K(i)) as well as excellent activity in human whole blood. These studies led to the discovery of highly potent TACE inhibitors with good DMPK profiles.


Assuntos
Proteínas ADAM/antagonistas & inibidores , Anti-Inflamatórios/química , Artrite Reumatoide/tratamento farmacológico , Inibidores de Proteases/química , Proteínas ADAM/metabolismo , Proteína ADAM17 , Acetileno/análogos & derivados , Acetileno/farmacocinética , Acetileno/uso terapêutico , Animais , Anti-Inflamatórios/farmacocinética , Anti-Inflamatórios/uso terapêutico , Cães , Haplorrinos , Humanos , Inibidores de Proteases/farmacocinética , Inibidores de Proteases/uso terapêutico , Ratos
14.
Bioorg Med Chem Lett ; 20(17): 5286-9, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20663669

RESUMO

We disclose further optimization of hydantoin TNF-alpha convertase enzyme (TACE) inhibitors. SAR with respect to the non-prime region of TACE active site was explored. A series of biaryl substituted hydantoin compounds was shown to have sub-nanomolar K(i), good rat PK, and good selectivity versus MMP-1, -2, -3, -7, -9, and -13.


Assuntos
Proteínas ADAM/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Proteína ADAM17 , Animais , Ratos , Relação Estrutura-Atividade
15.
Toxicol Sci ; 115(1): 295-303, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20156836

RESUMO

Ethylbenzene is an important industrial chemical that has recently been classified as a possible human carcinogen (International Agency of Research on Cancer class 2B), but the available data do not support the genotoxic mechanism of ethylbenzene-induced tumors in kidney. We investigated the effects of ethylbenzene on renal ultrastructure and explored the nongenotoxic mechanism of mitochondria-mediated apoptosis pathway. Forty male Sprague-Dawley rats were used as a vivo model with ethylbenzene inhalation for 13 weeks, and the metabolites of ethylbenzene, mandelic acid (MA), and phenylglyoxylic acid (PGA) in urine were examined by high-performance liquid chromatography. Meanwhile, the ultrastructure of renal tubular epithelial cells was observed, and cell apoptosis was detected via terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Furthermore, we investigated the expression levels of messenger RNA (mRNA) and protein of bax, bcl-2, cytochrome c, caspase-9, and caspase-3 in rat kidney. With respect to levels of MA, PGA, and MA + PGA, a significant dose-dependent increase was observed in 4335 and 6500 mg/m(3) ethylbenzene-treated groups against the control group. The mitochondria of renal tubular epithelial cells became a compact and vacuolar structure in 6500 mg/m(3) ethylbenzene-treated group, and ethylbenzene induced a significant increase in the number of apoptotic cells as compared to the control group. In addition, enhanced mRNA and protein expression levels of all measured genes were observed in various ethylbenzene-treated groups except the decreased bcl-2 expression levels. Our results indicated that ethylbenzene may induce apoptosis of renal tubular epithelial cells via mitochondria-mediated apoptotic pathways. MA and PGA in urine might be a parameter of biological dose in vivo after ethylbenzene inhalation.


Assuntos
Apoptose/efeitos dos fármacos , Derivados de Benzeno/toxicidade , Nefropatias/induzido quimicamente , Rim/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Animais , Derivados de Benzeno/farmacocinética , Biomarcadores/metabolismo , Peso Corporal/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Expressão Gênica/efeitos dos fármacos , Glioxilatos/urina , Marcação In Situ das Extremidades Cortadas , Exposição por Inalação , Rim/metabolismo , Rim/patologia , Nefropatias/metabolismo , Nefropatias/patologia , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/patologia , Masculino , Ácidos Mandélicos/urina , Mitocôndrias/ultraestrutura , Proteínas/genética , Proteínas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
16.
Bioorg Med Chem Lett ; 20(6): 1877-80, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-20172725

RESUMO

We disclose inhibitors of TNF-alpha converting enzyme (TACE) designed around a hydantoin zinc binding moiety. Crystal structures of inhibitors bound to TACE revealed monodentate coordination of the hydantoin to the zinc. SAR, X-ray, and modeling designs are described. To our knowledge, these are the first reported X-ray structures of TACE with a hydantoin zinc ligand.


Assuntos
Proteínas ADAM/antagonistas & inibidores , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Hidantoínas/farmacologia , Proteína ADAM17 , Inibidores Enzimáticos/química , Hidantoínas/química , Ligação de Hidrogênio , Modelos Moleculares , Relação Estrutura-Atividade , Difração de Raios X
17.
Artigo em Chinês | MEDLINE | ID: mdl-21241565

RESUMO

OBJECTIVE: To investigate the influence of ethylbenzene on oxidative damage, ultrastructure and the expressions of apoptosis-related genes in the rat brain tissues. METHODS: Four groups of 10 males of Sprague-Dawley rats were allocated randomly, and inhaled daily with different doses of ethylbenzene: 0, 433.5 mg/m³, 4335.0 mg/m³, and 6500.0 mg/m³ 6 h daily, 5 days per week for 13 weeks. The contents of glutathione (GSH) and malondialdehyde (MDA) and activity of acetylcholinesterase (AChE) were assayed, respectively. The ultrastructure of brain tissues was observed via electron microscope. The gene expression levels of Bax, Bcl-2, cytochrome C, caspase-9 and caspase-3 in brain tissues were measured by real-time polymerase chain reaction (PCR), respectively. RESULTS: The contents of MDA [(2.03 ± 0.56), (4.17 ± 1.31) nmol/mg pro] in the brain tissues of 4335.0 mg/m³ and 6500.0 mg/m³ ethylbenzene-treated groups were significantly higher than that [(1.08 ± 0.26) nmol/mg pro] in the control group (P < 0.05), while AChE activities [(0.321 ± 0.066), (0.276 ± 0.031), (0.202 ± 0.041) U/mg] and GSH contents [(35.19 ± 15.08), (33.42 ± 15.32), (27.99 ± 7.53) mg/g pro] in all ethylbenzene-treated groups were remarkably depressed (P < 0.05, P < 0.05, respectively). After 6500.0 mg/m³ ethylbenzene inhalation, the nucleolus exhibit demilune with decreased mitochondria. Electrondense of myelin occurred in the injured nerve, ascribing to lipid peroxidationed membrane. The gene expression level of Bax in brain tissue of 4335.0 mg/m³ and 6500.0 mg/m³ ethylbenzene-treated group was significantly higher than that in the control group (P < 0.05). Compared with the control group, the gene expression levels of cytochrome C, caspase-9 and caspase-3 in all ethylbenzene-treated groups were enhanced (P < 0.05, P < 0.05, respectively), while bcl-2 gene expression levels in all ethylbenzene-treated groups were decreased (P < 0.05). CONCLUSION: Ethylbenzene can induce oxidative damage and apoptosis in brain tissues. The apoptotic mechanism might be involved with up-regulation of Bax, cytochrome C, caspase-9 and caspase-3, as well as restraint of Bcl-2.


Assuntos
Apoptose , Derivados de Benzeno/toxicidade , Encéfalo/metabolismo , Encéfalo/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 9/metabolismo , Citocromos c/metabolismo , Dano ao DNA , Feminino , Expressão Gênica , Masculino , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Proteína X Associada a bcl-2/metabolismo
18.
Artigo em Chinês | MEDLINE | ID: mdl-20137408

RESUMO

OBJECTIVE: To investigate the influence of ethylbenzene on the levels of mandelic acid (MA) and phenylglyoxylic acid (PGA) in urine, the ultrastructure and the expressions of mitochondrial apoptotic-related genes in the rat nephridial tissues. METHODS: Four groups of 10 males of Sprague-Dawley rats were allocated randomly into four groups: control (C) group, low (L) group, moderate (M) group and high (H) group, and inhaled daily with different doses of ethylbenzene: 0, 433.5 mg/m(3), 4335 mg/m(3), and 6500 mg/m(3) 6 h per day, 5 days per week for 13 weeks. The mandelic acid and phenylglyoxylic acid in the urine was assayed by high performance liquid chromatography. The ultrastructure of nephridial tissue was observed via electron microscope. The protein expression levels of Bax, Bcl-2, cytochrome C, Caspase-9 and Caspase-3 in nephridial tissues were measured by Western blot, respectively. RESULTS: The levels of MA [(0.303 +/- 0.148) mg/L, (0.404 +/- 0.154) mg/L] and PGA [(0.168 +/- 0.104) mg/L, (0.174 +/- 0.092) mg/L] in the urine of M and H groups were significantly higher than that in the control and L group [(0.084 +/- 0.070) mg/L, (0.041 +/- 0.029) mg/L] (P < 0.05, respectively). It has been shown a dose-effect relationship between the contents of MA, PGA and MA + PGA and inhaled ethylbenzene, respectively. The mitochondria of rat nephridial tissue of H group became a compact and vacuolar structure with disorder and loss of cristae. The expression levels of Bax in mitochondria of nephridial tissues of M and H groups were significantly lower than that in the control group (P < 0.05). Caspase-3 expression level in H group was remarkably higher than that in the control group (P < 0.05). Compared with the control group, the expression levels of cytochrome C and Caspase-9 were enhanced, while the expression levels of Bcl-2 were restrained in all ethylbenzene-treated groups (P < 0.05, P < 0.05, respectively). The expression levels of Caspase-3 in M and H groups were significantly higher than that in the control group and L group (P < 0.05). CONCLUSION: Ethylbenzene can induce apoptosis in the cells of nephridial tissues. The apoptotic mechanism might be involved with up-regulation of Bax, cytochrome C, Caspase-9 and Caspase-3, as well as restraint of Bcl-2. The level of MA and PGA in the rat urine could be a parameter of biological dose in vivo after ethylbenzene inhalation.


Assuntos
Derivados de Benzeno/toxicidade , Glioxilatos/urina , Rim/ultraestrutura , Ácidos Mandélicos/urina , Animais , Apoptose , Caspase 3/metabolismo , Caspase 9/metabolismo , Modelos Animais de Doenças , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Proteína X Associada a bcl-2/metabolismo
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