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1.
Free Radic Biol Med ; 172: 578-589, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34242792

RESUMO

Acetaminophen (APAP) is the leading cause of acute liver failure (ALF), which is characterized by GSH depletion, oxidative stress and mitochondrial dysfunction. However, the specific mechanism of APAP-induced ALF remains to be clarified. In this study, we demonstrated that indoleamine 2,3-dioxygenase 1 (IDO1) aggravated APAP-induced ALF associated with excess lipid peroxidation, which was reversed by lipid peroxidation inhibitor (ferrostatin-1). Meanwhile, IDO1 deficiency effectively decreased the accumulation of reactive nitrogen species. Additionally, IDO1 deficiency prevented against APAP-induced liver injury through suppressing the activation of macrophages, thereby reduced their iron uptake and export, eventually reduced iron accumulation in hepatocytes through transferrin and transferrin receptor axis. In summary, our study confirmed that APAP-induced IDO1 aggravated ALF by triggering excess oxidative and nitrative stress and iron accumulation in liver. These results offer new insights for the clinical treatment of ALF or iron-dysregulated liver diseases in the future.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Dioxigenases , Falência Hepática Aguda , Acetaminofen/toxicidade , Animais , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Dioxigenases/metabolismo , Hepatócitos , Ferro/metabolismo , Fígado/metabolismo , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo
2.
Front Pharmacol ; 12: 801730, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35046824

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease and continues to rise in the worldwide. Limonin is a triterpenoid compound widely found in the fruits of citrus plants with a wide range of pharmacological effects, including anti-cancer, anti-inflammation, anti-viral, anti-oxidation and liver protection properties. However, the potential molecular mechanism of limonin on NAFLD in zebrafish remains unknown. In this study, zebrafish larvae were exposed to thioacetamide to establish an NAFLD model and the larvae were treated with limonin for 72 h simultaneously. The human liver cell line was stimulated with lipid mixture and meanwhile incubated with limonin for 24 h. The results showed that Limonin significantly reduced the accumulation of lipid droplets in the liver and down-regulated the levels of lipogenic transcription factors FASN and SREBP1 in NAFLD. Limonin suppressed macrophages infiltration and the down-regulated the relative expression levels of the pro-inflammatory factors IL-6, IL-1ß and TNF-α secreted by macrophages. Besides, limonin could reversed the reduction of glutathione and the accumulation of reactive oxygen species through up-regulating NRF2/HO-1 signaling pathway in the liver. In conclusion, this study revealed that limonin has a protective effect on NAFLD due to its resistance to lipid deposition as well as antioxidant and anti-inflammatory actions.

3.
Nutrition ; 95: 111490, 2021 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-35026483

RESUMO

OBJECTIVES: We aimed to establish reference intervals for water-soluble vitamins determined by liquid chromatography tandem mass spectrometry to improve the diagnosis of vitamin deficiency and outcomes of associated conditions. METHODS: In this retrospective analysis of 24 810 specimens, we aimed to examine sex-, age-, and season-related variations in vitamin levels in different groups, set reference-value intervals for vitamin levels, and evaluate these reference values against those recommended by manufacturers. RESULTS: Levels of vitamins B3, B5, B6, B7, and B12 were higher, and those of vitamins B2, B9, and C were lower, in men than in women. There were seasonal variations in levels of vitamins B1, B3, B5, B6, B9, B12, and C. Levels of vitamins B1, B2, B3, B5, B6, B7, B9, and C differed across age groups; vitamin B1 displayed significant differences between ages 0 to 14 years and adults compared with reference change values. The lower limits of vitamins B1 (ages 15-100 y), B2, B3, B7, and C were lower, and that of vitamin B5 was higher, than the recommended reference values. Finally, the upper limits of vitamins B1, B3, B5, B6, and B7 were lower than the recommended values. CONCLUSIONS: For values obtained using liquid chromatography tandem mass spectrometry, the lower limits of reference intervals for vitamins B1 (ages 15-100 y), B2, B3, B7, and C should be lowered, that of vitamin B5 should be raised, and the upper limits of reference intervals for vitamins B1, B3, B5, B6, and B7 should be lowered.

4.
Carcinogenesis ; 41(11): 1473-1484, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-32710740

RESUMO

The present study was conducted to clarify the cooperative significance of epigenomic and genomic abnormalities during gastric carcinogenesis. Using 21 samples of normal control gastric mucosa (C), 109 samples of non-cancerous gastric mucosa (N) and 105 samples of cancerous tissue (T) from 109 patients with primary gastric adenocarcinomas, genome-wide DNA methylation analysis was performed using Infinium assay. Among these samples, 66 paired N and corresponding T samples were subjected to whole-exome and single nucleotide polymorphism array analyses. As had been shown in our previous study, 109 patients were clustered clinicopathologically into least aggressive Cluster A (n = 20), most aggressive Cluster B1 (n = 20) and Cluster B2 (n = 69). Most DNA methylation alterations in each cluster had already occurred even in N samples compared with C samples, and DNA methylation alterations at the precancerous N stage were inherited by the established cancers themselves. Recurrent single nucleotide variants and insertions/deletions resulting in functional disruption of the proteins encoded by the ABCA10, BNC2, CDH1, CTNNB1, SMAD4 and VAV2 genes were specific to Cluster B1, whereas those of the APC, EGFR, ERBB2, ERBB3, MLH1 and MUC6 genes were specific to Cluster A. MetaCore pathway analysis revealed that the epigenomically affected TWIST1 gene and genomically affected CDH1, CTNNB1, MMP9, TLN2, ROCK1 and SMAD4 genes were accumulated in signaling pathways related to cell adhesion, cytoskeleton remodeling and epithelial-mesenchymal transition in Cluster B1. These data indicate that epigenomic alterations at the precancerous stage are important in gastric carcinogenesis and that epigenomic and genomic alterations cooperatively underlie the aggressiveness of gastric adenocarcinomas.


Assuntos
Adenocarcinoma/patologia , Biomarcadores Tumorais/metabolismo , Adesão Celular , Epigenômica/métodos , Transição Epitelial-Mesenquimal , Polimorfismo de Nucleotídeo Único , Neoplasias Gástricas/patologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Metilação de DNA , Epigênese Genética , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Sequenciamento Completo do Exoma
5.
Free Radic Biol Med ; 148: 151-161, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-31877357

RESUMO

Ferroptosis is a new regulated cells death manner defined as results of iron-dependent accumulation of lipid peroxidation. However, the specific mechanisms of regulating ferroptosis remain unclear. In our present study, we demonstrated that Caveolin-1 (Cav-1) played a central role in protecting hepatocytes against ferroptosis in autoimmunity-mediated hepatitis (AIH). The down-regulated Cav-1 in liver tissues, accompanied by ferroptotic events and RNS production, were contributed to the outcome of ConA-induced hepatic damage, which were rescued by ferrostatin-1 (an inhibitor of ferroptosis) in vivo and in vitro. Additionally, Cav-1 deficiency aggravated ConA-induced hepatocellular death and ferroptosis associated with excessive nitrogen stress response. Short hairpin RNA of Cav-1 in hepatocytes promoted ferroptosis and nitrative stress in response to erastin in vitro, which was ameliorated by Cav-1 over-expression. Meanwhile, administration of the iNOS inhibitor (1400W) or ONOO- scavenger (Fe-TMPyP), diminished reactive nitrogen species (RNS), remarkably reduced hepatocytes ferroptosis and attenuated ConA-induced liver damage. Furthermore, immune inhibition by gadolinium chloride (GdCl3), a well-known Kupffer cell depletor, elevated hepatic Cav-1 but inhibited ferroptosis and nitrative stress under ConA exposure. In conclusion, these data revealed a novel molecular mechanism of ferroptosis with the Cav-1 regulation was essential for pathogenesis of ConA-induced hepatitis. Downstream of Cav-1, RNS-mediated ferroptosis was a pivotal step that drives the execution of acute immune-mediated hepatic damage.


Assuntos
Ferroptose , Caveolina 1/genética , Hepatócitos , Peroxidação de Lipídeos , Nitrogênio
6.
Mol Clin Oncol ; 7(5): 903-910, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29181186

RESUMO

Little progress has been made in the treatment of advanced cancer. Dendritic cells (DCs) plus cytokine-induced killer (CIK) cells have exhibited antitumor effects. Thus, the aim of the present study was to evaluate the clinical efficacy of DC-CIK cell treatment in patients with advanced cancer. A paired study including 57 patients treated with DC-CIK cells (DC-CIK group) and 33 patients treated with best supportive care alone (BSC group) was performed. The patients in the DC-CIK group were matched to those in the control group in terms of sex, age, tumor type and clinical stage. T-cell subsets were detected and overall survival (OS) was compared between the two groups. The results demonstrated that CD4+/CD25+ and CD8+/CD28- subsets significantly decreased following DC-CIK immunotherapy (P<0.05). The CD3+, CD3+/CD8+, CD8+/CD28+ and CD3+/CD56+ T-cell subsets were significantly increased in the DC-CIK group compared with the BSC group, while the CD8+/CD28- subset was significantly decreased. Univariate analysis demonstrated that a lower CD8+/CD28- and a higher CD8+/CD28+ ratio were associated with prolonged OS in advanced cancer patients. In addition, DC-CIK treatment administration, age (>60 vs. <60 years), clinical stage and the frequency of CIK treatment significantly affected the OS of patients in the DC-CIK group. A CD8+/CD28- ratio of <21.12 was found to decrease the hazard ratio (HR) of OS to 0.50 [95% confidence interval (CI): 0.29-0.87] and a CD8+/CD28+ ratio >9.04 was found to decrease the HR of OS to 0.45 (95% CI: 0.21-0.98). No serious side effects were observed in the DC-CIK group. Taken together, these data indicate that DC-CIK infusions were able to change the ratios of the T-cell subsets, which increased the T helper cell and cytotoxic T lymphocyte subsets, while it decreased regulatory T lymphocyte subsets. Thus, this method of immunotherapy was found to improve the imbalance in the immune system and prolong the OS in patients with advanced cancer.

7.
J Stroke Cerebrovasc Dis ; 24(5): 912-20, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25804562

RESUMO

BACKGROUND: Thyroid disease is the medical condition impairing function of the thyroid. Among this disorder category, hyperthyroidism is that the thyroid gland produces excessive amounts of thyroid hormones whereas hypothyroidism is that the thyroid gland does not produce enough thyroid hormone. Various studies have supported the comorbid association between thyroid disease and cardiovascular disorder. However, there is insufficient evidence to prove the relationship between cerebrovascular disease (CVD) and thyroid disease. METHODS: In this study, we tried to verify that thyroid disease increases the risk of CVD development employing a population-based database, National Health Insurance Research Database of Taiwan. A total of 16,808 hyperthyroidism cases and 5793 hypothyroidism patients with corresponding control subjects were studied, respectively. Hazard ratio (HR) by the Cox regression was used to quantify risk of CVD in different groups of subjects, that is, case patients versus matched controls. Further stratification studies for risk factors of CVD were performed to evaluate the comorbid association between CVD and hyperthyroidism/hypothyroidism. RESULTS: Evaluation results have shown that hyperthyroidism increased 38% of the hazard of developing follow-up CVD (adjusted HR, 1.38) whereas hypothyroidism increased even higher the risk (adjusted HR, 1.89). Further stratification studies for risk factors of CVD suggested that the comorbid association between hypothyroidism and CVD was comparable to those influences from cardiac risk factors, such as diabetes mellitus, hyperlipidemia, hypertension, or renal failure and so forth. CONCLUSIONS: Thyroid disease may predispose to onset of CVD. Advanced analysis is required to investigate the pathologic mechanism underlying the association between CVD and thyroid disease.


Assuntos
Transtornos Cerebrovasculares/epidemiologia , Doenças da Glândula Tireoide/epidemiologia , Adulto , Estudos de Coortes , Planejamento em Saúde Comunitária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Programas Nacionais de Saúde/estatística & dados numéricos , Modelos de Riscos Proporcionais , Fatores de Risco , Taiwan/epidemiologia , Doenças da Glândula Tireoide/classificação , Adulto Jovem
8.
BMC Genomics ; 15: 578, 2014 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-25005802

RESUMO

BACKGROUND: Agarwood is derived from Aquilaria trees, the trade of which has come under strict control with a listing in Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora. Many secondary metabolites of agarwood are known to have medicinal value to humans, including compounds that have been shown to elicit sedative effects and exhibit anti-cancer properties. However, little is known about the genome, transcriptome, and the biosynthetic pathways responsible for producing such secondary metabolites in agarwood. RESULTS: In this study, we present a draft genome and a putative pathway for cucurbitacin E and I, compounds with known medicinal value, from in vitro Aquilaria agallocha agarwood. DNA and RNA data are utilized to annotate many genes and protein functions in the draft genome. The expression changes for cucurbitacin E and I are shown to be consistent with known responses of A. agallocha to biotic stress and a set of homologous genes in Arabidopsis thaliana related to cucurbitacin bio-synthesis is presented and validated through qRT-PCR. CONCLUSIONS: This study is the first attempt to identify cucurbitacin E and I from in vitro agarwood and the first draft genome for any species of Aquilaria. The results of this study will aid in future investigations of secondary metabolite pathways in Aquilaria and other non-model medicinal plants.


Assuntos
Cucurbitacinas/análise , Genoma de Planta , Thymelaeaceae/genética , Cromatografia Líquida de Alta Pressão , Cucurbitacinas/química , Cucurbitacinas/metabolismo , Enzimas/genética , Enzimas/metabolismo , Biblioteca Gênica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Análise de Sequência de RNA , Espectrometria de Massas por Ionização por Electrospray , Thymelaeaceae/química , Thymelaeaceae/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-24392299

RESUMO

In this study, we will propose a density estimation based data analysis procedure to investigate the co-morbid associations between migraine and the suspected diseases. The primary objective of this study has aimed to develop a novel analysis procedure that can discover insightful knowledge from large medical databases. The entire analysis procedure consists of two stages. During the first stage, a kernel density estimation algorithm named relaxed variable kernel density estimation (RVKDE) is invoked to identify the samples of interest. Then, in the second stage, a density estimation algorithm based on generalized Gaussian components and named G2DE is invoked to provide a summarized description of the distribution. The results obtained by applying the proposed two-staged procedure to analyze co-morbidities of migraine revealed that the proposed procedure could effectively identify a number of clusters of samples with distinctive characteristics. The results further revealed that the distinctive characteristics of the clusters extracted by the proposed procedure were in conformity with the observations reported in recently published articles. Accordingly, it is conceivable that the proposed analysis procedure can be exploited to provide valuable clues of pathogenesis and facilitate development of proper treatment strategies.

11.
PLoS One ; 7(3): e33941, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22442736

RESUMO

Previous research suggests that a co-morbid relationship exists between migraine and endometriosis; however, results have been inconsistent. In addition, female hormones, which are important in the pathogenesis and management of endometriosis, have been reported to precipitate migraine attacks and may confound the results. The aim of this population-based cohort study was to explore the relationship between migraine and endometriosis in women of reproductive age (18-51 years). Data were derived from the National Health Insurance Research Database of Taiwan, which contains outpatient and inpatient records from 2000 to 2007. Our study cohort included 20,220 endometriosis patients and 263,767 controls without endometriosis. We analyzed the prevalence of migraine in these women as recorded during the eight years of the database. Our results found that patients with endometriosis were more likely to suffer migraine headaches compared to controls (odds ratio [OR], 1.70; 95% confidence interval [CI] [1.59, 1.82]; p<0.001). In addition, the co-morbid association between migraine and endometriosis remained significant after the data were controlled for age and frequently utilized hormone therapies (OR, 1.37; 95% CI, [1.27, 1.47]; p<0.001). The results of this cohort study support the existence of a co-morbid relationship between migraine and endometriosis, even after adjusting for the possible effects of female hormone therapies on migraine attacks.


Assuntos
Endometriose/complicações , Endometriose/epidemiologia , Transtornos de Enxaqueca/epidemiologia , Transtornos de Enxaqueca/etiologia , Adolescente , Adulto , Estudos de Coortes , Bases de Dados Factuais , Endometriose/terapia , Feminino , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Pessoa de Meia-Idade , Prevalência , Taiwan/epidemiologia
12.
BMC Genomics ; 10 Suppl 3: S22, 2009 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-19958486

RESUMO

BACKGROUND: Proteins are dynamic macromolecules which may undergo conformational transitions upon changes in environment. As it has been observed in laboratories that protein flexibility is correlated to essential biological functions, scientists have been designing various types of predictors for identifying structurally flexible regions in proteins. In this respect, there are two major categories of predictors. One category of predictors attempts to identify conformationally flexible regions through analysis of protein tertiary structures. Another category of predictors works completely based on analysis of the polypeptide sequences. As the availability of protein tertiary structures is generally limited, the design of predictors that work completely based on sequence information is crucial for advances of molecular biology research. RESULTS: In this article, we propose a novel approach to design a sequence-based predictor for identifying conformationally ambivalent regions in proteins. The novelty in the design stems from incorporating two classifiers based on two distinctive supervised learning algorithms that provide complementary prediction powers. Experimental results show that the overall performance delivered by the hybrid predictor proposed in this article is superior to the performance delivered by the existing predictors. Furthermore, the case study presented in this article demonstrates that the proposed hybrid predictor is capable of providing the biologists with valuable clues about the functional sites in a protein chain. The proposed hybrid predictor provides the users with two optional modes, namely, the high-sensitivity mode and the high-specificity mode. The experimental results with an independent testing data set show that the proposed hybrid predictor is capable of delivering sensitivity of 0.710 and specificity of 0.608 under the high-sensitivity mode, while delivering sensitivity of 0.451 and specificity of 0.787 under the high-specificity mode. CONCLUSION: Though experimental results show that the hybrid approach designed to exploit the complementary prediction powers of distinctive supervised learning algorithms works more effectively than conventional approaches, there exists a large room for further improvement with respect to the achieved performance. In this respect, it is of interest to investigate the effects of exploiting additional physiochemical properties that are related to conformational ambivalence. Furthermore, it is of interest to investigate the effects of incorporating lately-developed machine learning approaches, e.g. the random forest design and the multi-stage design. As conformational transition plays a key role in carrying out several essential types of biological functions, the design of more advanced predictors for identifying conformationally ambivalent regions in proteins deserves our continuous attention.


Assuntos
Proteínas/análise , Análise de Sequência de Proteína/métodos , Algoritmos , Biometria , Modelos Moleculares , Estrutura Terciária de Proteína , Proteínas/química
13.
BMC Res Notes ; 1: 51, 2008 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-18710504

RESUMO

BACKGROUND: Though prediction of protein secondary structures has been an active research issue in bioinformatics for quite a few years and many approaches have been proposed, a new challenge emerges as the sizes of contemporary protein structure databases continue to grow rapidly. The new challenge concerns how we can effectively exploit all the information implicitly deposited in the protein structure databases and deliver ever-improving prediction accuracy as the databases expand rapidly. FINDINGS: The new challenge is addressed in this article by proposing a predictor designed with a novel kernel density estimation algorithm. One main distinctive feature of the kernel density estimation based approach is that the average execution time taken by the training process is in the order of O(nlogn), where n is the number of instances in the training dataset. In the experiments reported in this article, the proposed predictor delivered an average Q3 (three-state prediction accuracy) score of 80.3% and an average SOV (segment overlap) score of 76.9% for a set of 27 benchmark protein chains extracted from the EVA server that are longer than 100 residues. CONCLUSION: The experimental results reported in this article reveal that we can continue to achieve higher prediction accuracy of protein secondary structures by effectively exploiting the structural information deposited in fast-growing protein structure databases. In this respect, the kernel density estimation based approach enjoys a distinctive advantage with its low time complexity for carrying out the training process.

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