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1.
Front Endocrinol (Lausanne) ; 13: 868105, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35528018

RESUMO

Objective: This study aimed to investigate the inhibition of human important phase II metabolic enzyme sulfotransferases (SULTs) by phthalate monoesters, which are important metabolites of phthalate esters (PAEs). Method: Recombinant SULT-catalyzed metabolism of p-nitrophenol (PNP) was employed as the probe reactions of SULTs to investigate the inhibition of 8 kinds of phthalate monoesters towards SULT isoforms. An in vitro incubation system was utilized for preliminary screening, and 100 µM of phthalate monoesters was used. Inhibition kinetics were carried out to determine the inhibition of SULTs by phthalate monoesters. Result: Multiple phthalate monoesters have been demonstrated to exert strong inhibition potential towards SULT1A1, SULT1B1, and SULT1E1, and no significant inhibition of phthalate monoesters towards SULT1A3 was found. The activity of SULT1A1 was strongly inhibited by mono-hexyl phthalate (MHP), mono-octyl phthalate (MOP), mono-benzyl phthalate (MBZP), and mono-ethylhexyl phthalate (MEHP). Monobutyl phthalate (MBP), MHP, MOP, mono-cyclohexyl phthalate (MCHP), and MEHP significantly inhibited the activity of SULT1B1. MHP, MOP, and MEHP significantly inhibited the activity of SULT1E1. MOP was chosen as the representative phthalate monoester to determine the inhibition kinetic parameters (Ki) towards SULT1B1 and SULT1E1. The inhibition kinetic parameters (Ki) were calculated to be 2.23 µM for MOP-SULT1B1 and 5.54 µM for MOP-SULT1E1. In silico docking method was utilized to understand the inhibition mechanism of SULT1B1 by phthalate monoesters. Conclusions: All these information will be beneficial for understanding the risk of phthalate monoester exposure from a new perspective.


Assuntos
Ésteres , Sulfotransferases , Humanos , Ácidos Ftálicos , Isoformas de Proteínas , Sulfotransferases/metabolismo
2.
Sci Bull (Beijing) ; 66(13): 1342-1357, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-36654156

RESUMO

Thousands of proteins undergo arginine methylation, a widespread post-translational modification catalyzed by several protein arginine methyltransferases (PRMTs). However, global understanding of their biological functions is limited due to the lack of a complete picture of the catalytic network for each PRMT. Here, we systematically identified interacting proteins for all human PRMTs and demonstrated their functional importance in mRNA splicing and translation. We demonstrated significant overlapping of interactomes of human PRMTs with the known methylarginine-containing proteins. Different PRMTs are functionally redundant with a high degree of overlap in their substrates and high similarities between their putative methylation motifs. Importantly, RNA-binding proteins involved in regulating RNA splicing and translation contain highly enriched arginine methylation regions. Moreover, inhibition of PRMTs globally alternates alternative splicing (AS) and suppresses translation. In particular, ribosomal proteins are extensively modified with methylarginine, and mutations in their methylation sites suppress ribosome assembly, translation, and eventually cell growth. Collectively, our study provides a global view of different PRMT networks and uncovers critical functions of arginine methylation in regulating mRNA splicing and translation.

3.
Ther Clin Risk Manag ; 15: 811-821, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308679

RESUMO

Purpose: Previous research findings on the association between serum total bilirubin (TB) and cardiovascular events varied with different study populations. Our objective was to clarify the association between serum TB at admission and long-term adverse outcomes in patients with acute coronary syndrome (ACS) and stable angina (SA) undergoing percutaneous coronary intervention (PCI). Patients and methods: This prospective cohort study included 2,502 patients who underwent PCI. Information on the study population was obtained from the Dryad Digital Repository. The patients were divided into two groups: high (>0.60 mg/dL) and low TB groups (≤0.60 mg/dL) based on the optimal cutoff value achieved in the receiver operating characteristic curve analysis. The relationships between serum TB at admission and clinical outcomes after PCI were analyzed in multivariable logistic regression models and restricted cubic spline. Results: In all patients undergoing PCI, TB>0.60 mg/dL was associated with major adverse cardiovascular events (MACE) and cardiovascular death during a 3-year follow-up. The odds ratio (95% confidence interval) was 1.60 (1.22-2.10) and 1.81 (1.22-2.70) for MACE and cardiovascular death, respectively. The association between TB and MACE was not altered by clinical presentation (p for interaction=0.949). Conclusion: In patients with ACS and SA undergoing PCI, elevated serum TB was associated with increased risk of MACE and cardiovascular death.

4.
Int J Mol Med ; 39(6): 1452-1460, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28440421

RESUMO

Allicin is considered anti-atherosclerotic due to its antioxidant and anti-inflammatory effects, which makes it an important drug for the prevention and treatment of atherosclerosis. However, the effects of allicin on foam cells are unclear. Thus, in this study, we examined the effects of allicin on lipid accumulation via peroxisome proliferator-activated receptor Î³ (PPARγ)/liver X receptor α (LXRα) in THP­1 macrophage-derived foam cells. THP­1 cells were exposed to 100 nM phorbol myristate acetate (PMA) for 24 h, and then to oxydized low-density lipoprotein (ox-LDL; 50 mg/ml) to induce foam cell formation. The results of Oil Red O staining and high-performance liquid chromatography (HPLC) revealed showed that pre-treatment of the foam cells with allicin decreased total cholesterol, free cholesterol (FC) and cholesterol ester levels in cells, and also decreased lipid accumulation. Moreover, allicin upregulated ATP binding cassette transporter A1 (ABCA1) expression and promoted cholesterol efflux. However, these effects were significantly abolished by transfection with siRNA targeting ABCA1. Furthermore, PPARγ/LXRα signaling was activated by allicin treatment. The allicin-induced upregulation of ABCA1 expression was also abolished by PPARγ inhibitor (GW9662) and siRNA or LXRα siRNA co-treatment. Overall, our data demonstrate that the allicin-induced upregulation of ABCA1 promotes cholesterol efflux and reduces lipid accumulation via PPARγ/LXRα signaling in THP­1 macrophage-derived foam cells.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/genética , Células Espumosas/efeitos dos fármacos , Receptores X do Fígado/metabolismo , PPAR gama/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ácidos Sulfínicos/farmacologia , Regulação para Cima/efeitos dos fármacos , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Linhagem Celular , Colesterol/metabolismo , Dissulfetos , Células Espumosas/metabolismo , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , RNA Mensageiro/genética
5.
Med Sci Monit ; 23: 563-570, 2017 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-28139552

RESUMO

BACKGROUND The abnormal activity of Sirtuin 1 (Sirt1) is closely related to the aging of vascular endothelial cells. As a bioactive molecule, allicin has antioxidant, anti-inflammatory, and lipid-regulating mechanisms. However, few reports about the relationship of allicin and Sirt1 have been published. In this study, we aimed to elucidate the effect of allicin on Human Umbilical Vein Endothelial Cells (HUVECs) aging induced by hydrogen peroxide (H2O2) and the role of Sirt1 in this phenomenon. MATERIAL AND METHODS HUVEC were exposed to H2O2 to establish the aging model. The expression of protein and RNA were detected by Western blot and Reverse transcription-quantitative polymerase chain reaction. The 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to assess cell viability. Sirt1 enzyme activity assay was used to analyze enzymatic activity. Reactive oxygen species was detected by dichlorofluorescein diacetate (DCFH-DA). Cell aging was detected by Senescence ß-Galactosidase (SA-ß-gal) staining. RESULTS Results of this study revealed that pretreating HUVECs with 5 ng/mL allicin before exposure to H2O2 resulted in increased cell viability and reduced reactive oxygen species generation. Western blot and quantitative real-time polymerase chain reaction (qRT-PCR) analysis showed that H2O2 attenuated the phosphorylation and activation of Sirt1 and increased the expression of plasminogen activator inhibitor-1(PAI-1) protein. Moreover, H2O2 also promoted HUVEC aging. These effects were significantly alleviated by 5 ng/mL allicin co-treatment. Furthermore, the anti-aging effects of allicin were abolished by the Sirt1 inhibitor nicotinamide (NAM). CONCLUSIONS Overall, the results demonstrated that allicin protects HUVECs from H2O2-induced oxidative stress and aging via the activation of Sirt1.


Assuntos
Senescência Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Sirtuína 1/farmacologia , Ácidos Sulfínicos/farmacologia , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dissulfetos , Interações Medicamentosas , Células Endoteliais , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Peróxido de Hidrogênio/farmacologia , Niacinamida/farmacologia , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Substâncias Protetoras/farmacologia , Espécies Reativas de Oxigênio/metabolismo , beta-Galactosidase/metabolismo
6.
Int J Ophthalmol ; 9(2): 271-4, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26949649

RESUMO

AIM: To investigate factors associated with responses to intravitreal bevacizumab (IVB) in naive idiopathic choroidal neovascularization (iCNV) by high domain optical coherence tomography (OCT). METHODS: We retrospectively reviewed clinical data of 40 eyes of iCNV patients who received a single or multiple IVB on an as-needed basis (1.25 mg/0.05 mL). One month after the first injection, subretinal fluid (SRF) volume was evaluated and the eyes were divided into 3 groups based on responses to IVB. Good, moderate, and poor responses were defined as 61%-99%, 30%-60%, and <30% resolution of SRF on OCT after IVB in iCNV, respectively. OCT findings were analyzed to find factors associated with difference in response levels. Comparisons were made using Wilcoxon's matched-pairs signed-rank test, the Mann-Whitney U test for means with continuous data and Fisher's exact test for categorical data. RESULTS: The mean number of IVB was 1.28±1.50 and mean follow up time was 3.60±1.20mo. At postoperative 1mo, there were 8 (20%) eyes in good response, 20 (50%) in moderate response and 12 (30%) eyes in poor response group and at last visit there were 28 good responders (70%), 8 (20%) moderate responders and 4 (10%) poor responders. Statistically significant difference was detected between good responders and non good responders in choroidal neovessels thickness (P=0.029), SRF height (P=0.049) and SRF volume (P=0.031) at post treatment 1mo. CONCLUSION: OCT is a valuable diagnostic tool. Decrease in choroidal neovessels thickness, SRF height and volume predicts favorable response of iCNV to IVB therapy.

7.
Oncol Lett ; 11(2): 1499-1505, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26893768

RESUMO

The hepatocyte growth factor (HGF)/c-Met signaling pathway results in cancer cell scattering and invasion, and has been reported to participate in several types of cancer, including prostate and colorectal cancer. The downstream phosphorylation cascade of HGF, particularly the mitogen-activated protein kinase and phosphoinositide 3-kinase/AKT signaling pathway, regulates epithelial-mesenchymal transition (EMT). However, the mechanism by which these signaling pathways govern EMT, and whether certain kinases are able to respond to specific EMT effectors, remains to be elucidated. In the present study, an increase in the levels of vimentin, rather than co-regulation of certain EMT marker proteins, was observed in response to HGF-induced EMT in DU145 prostate cancer cells. In addition, it was observed that curcumin abrogated HGF-induced DU145 cell scattering and invasion. Furthermore, curcumin was able to effectively inhibit the HGF-induced increase in the levels of vimentin by downregulating the expression of phosphorylated c-Met, extracellular signal-regulated kinase and Snail. In conclusion, the results of the present study demonstrated that curcumin was able to reverse HGF-induced EMT, possibly by inhibiting c-Met expression in DU145 prostate cancer cells.

8.
J Ayub Med Coll Abbottabad ; 27(2): 259-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26411092

RESUMO

BACKGROUND: Idiopathic choroidal neovascularization (ICNV) is a unilateral ocular disease which occurs in patients younger than 50 years and accounts for approximately 17% of patients with CNV. We evaluated microstructural effects of intravitreal bevacizumab in eyes with treatment-naïve idiopathic choroidal neovascularisation. METHODS: In this case series study we reviewed the treatment and follow up records of 40 symptomatic eyes having ICNV, who received an intravitreal injection of bevacizumab (1.25 mg/0.05 mL) followed by additional doses based on optical coherence tomography findings, including intraretinal fluid, subretinal fluid, or pigment epithelial detachment. We analysed the results of best-corrected visual acuity, central retinal thickness, neovessels size (thickness and diameter), and disrupted photoreceptor length at baseline and at final visit with paired t-test. Difference in best corrected visual acuity was correlated with difference in optical coherence tomography parameters by Pearson's correlation. RESULTS: Mean logarithm of the minimum angle of resolution best-corrected visual acuity improved from 0.60 initially to 0.24 after treatment (p=0.01). Difference in mean central retinal thickness (82.65 +/- 44.1) pm, choroidal neovessels thickness (149.58 +/- 71.1) microm, choroidal neovessels diameter (1250.8 +/- 145.1) pm, photoreceptor disruption length (2141.20 +/- 318.8) microm were all statistically significant (p=0.01). Difference in best corrected visual acuity was correlated with optical coherence tomography parameters found no statistically significant difference. CONCLUSION: Intravitreal bevacizumab therapy is safe and well tolerated in ICNV eyes. Restoration of photoreceptor disruption length, decrease in central retinal thickness and choroidal neovessels size has association with visual improvement in idiopathic choroidal neovascularisation.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Corioide/patologia , Neovascularização de Coroide/tratamento farmacológico , Tomografia de Coerência Óptica/métodos , Adolescente , Adulto , Inibidores da Angiogênese/administração & dosagem , Bevacizumab , Corioide/efeitos dos fármacos , Neovascularização de Coroide/diagnóstico , Feminino , Angiofluoresceinografia , Fundo de Olho , Humanos , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual , Adulto Jovem
9.
DNA Cell Biol ; 34(9): 561-72, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26102194

RESUMO

Curcumin, a traditional Chinese derivative from the rhizomes of Curcuma longa, is beneficial to health by modulating lipid metabolism and suppressing atherogenesis. A key part of atherosclerosis is the failure of macrophages to restore their cellular cholesterol homeostasis and the formation of foam cells. In this study, results showed that curcumin dramatically increased the expression of ATP-binding cassette transporter 1 (ABCA1), promoted cholesterol efflux from THP-1 macrophage-derived foam cells, and reduced cellular cholesterol levels. Curcumin activated AMP-activated protein kinase (AMPK) and SIRT1, and then activated LXRα in THP-1 macrophage-derived foam cells. Inhibiting AMPK/SIRT1 activity by its specific inhibitor or by small interfering RNA could inhibit LXRα activation and abolish curcumin-induced ABCA1 expression and cholesterol efflux. Thus, curcumin enhanced cholesterol efflux by upregulating ABCA1 expression through activating AMPK-SIRT1-LXRα signaling in THP-1 macrophage-derived foam cells. This study describes a possible mechanism for understanding the antiatherogenic effects of curcumin on attenuating the progression of atherosclerosis.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/metabolismo , Colesterol/metabolismo , Curcumina/farmacologia , Células Espumosas/metabolismo , Hipolipemiantes/farmacologia , Transportador 1 de Cassete de Ligação de ATP/genética , Adenilato Quinase/metabolismo , Diferenciação Celular , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Espumosas/efeitos dos fármacos , Humanos , Receptores X do Fígado , Receptores Nucleares Órfãos/metabolismo , Transdução de Sinais , Sirtuína 1/metabolismo , Regulação para Cima
10.
J Stroke Cerebrovasc Dis ; 24(6): 1351-6, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25797431

RESUMO

BACKGROUND: Large-artery atherosclerotic stroke (LAAs) is related to carotid plaque, but the mechanical mechanism is unclear. We aimed to use ultrasonic velocity vector imaging (VVI) technique to study the mechanical difference of carotid plaque in patients with LAAs and controls. METHODS: We enrolled 43 LAAs patients and 38 controls but all showing plaque on carotid ultrasonography. Ultrasonic VVI technique was used to analyze radial systolic and diastolic peak velocity (R-vs, R-vd), radial and circumferential peak strain (R-s, C-s) and radial displacement (R-dis) of carotid plaque. RESULTS: Compared with controls, LAAs patients showed higher pulse pressure (P = .001), pulse pressure index (PPI, P = .006), and greater stress at carotid plaque as manifested by higher absolute value of radial diastolic peak velocity (R-vd, P = .021), radial systolic peak velocity (R-vs, P = .007), radial peak strain (R-s, P = .015), and radial displacement (R-dis, P = .022). PPI was significantly correlated with R-vs (r = -.274, P = .013), R-vd (r = .304, P = .006), and R-dis (r = -.28, P = .011). But there was no correlation between R-s and blood pressure. R-s was screened to be the most predictable parameters for LAAs (odds ratio, 1.118; 95% confidence interval, 1.012∼1.236; P = .029). The area under the curve of R-s was .627. CONCLUSIONS: Radial peak strain (R-s) is a predictable parameter for the occurrence of LAAs. We predict using ultrasonic VVI technique to analyze whether the mechanics of carotid plaque is helpful to screen patients with high risks of LAAs.


Assuntos
Estenose das Carótidas/diagnóstico por imagem , Placa Aterosclerótica/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Estenose das Carótidas/fisiopatologia , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Ultrassom
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