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1.
Basic Res Cardiol ; 111(2): 11, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26780215

RESUMO

N-myc downstream-regulated gene 4 (NDRG4) is expressed weakly in heart and has been reported to modulate cardiac development and QT interval duration, but the role of NDRG4 in myocardial ischemia/reperfusion (I/R) injury remains unknown. In the present study, we analyzed the expression as well as potential function of cardiac NDRG4 and investigated how NDRG4 expression is regulated by inflammation. We found that NDRG4 was weakly expressed in cardiomyocytes and that its expression increased significantly both in I/R injured heart and in hypoxia-reoxygenation (H/R) injured neonatal rat ventricular myocytes (NRVMs). The increased NDRG4 expression aggravated myocardial I/R injury by inhibiting the activation of the reperfusion injury salvage kinase (RISK) pathway. Forced over-expression of NDRG4 inhibited RISK activation and exacerbated injury not only in I/R injured heart, but also in H/R treated NRVMs, whereas short hairpin RNA (shRNA)-mediated knock-down of NDRG4 enhanced RISK activation and attenuated injury. Upon injury, myocardial NDRG4 expression was induced by tumor necrosis factor-α (TNF-α) through nuclear factor kappa B (NF-κB), and we found that pre-treatment with inhibitors of either TNF-α or NF-κB blocked NDRG4 expression as well as I/R injury in vivo and H/R injury in vitro. Our study indicates that up-regulation of NDRG4 aggravates myocardial I/R injury by inhibiting activation of the RISK pathway, thereby identifying NDRG4 as a potential therapeutic target in I/R injury.


Assuntos
Proteínas Musculares/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Animais , Animais Recém-Nascidos , Células Cultivadas , Masculino , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
2.
Cell Tissue Res ; 366(2): 467-481, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27397680

RESUMO

An increasingly pro-oxidant environment has been widely implicated in causing dysfunction of testicular steroidogenesis, but little progress has been made in understanding the underlying molecular mechanism. Here, we report that gamma-glutamyl transferase 5 (GGT5), a key metabolism component responsible for the catalysis of important anti-oxidant glutathione (GSH), is predominantly expressed in mammalian Leydig cells (LCs). Deregulated GGT5 expression negatively correlates with testosterone deficiency in the testes of type 2 diabetic mice. Consistently, overexpression of GGT5 potentiates the susceptibility of TM3 LCs to spontaneous oxidative stress during luteinizing hormone (LH)-stimulated steroidogenesis. From a mechanistic standpoint, the deleterious effect of GGT5 overexpression on testicular steroidogenesis may stem from an alteration of the local redox state because of GSH deficiency. The above-mentioned response might involve the impairment of extracellular signal-related kinase activation mediated directly by oxidative injury or indirectly by abnormal P38 activation, which in turn inhibits steroidogenic acute regulatory protein abundance in mitochondria and thus significantly sabotages the rate-limiting step during LH-induced steroidogenesis. Alternatively, GGT5 overexpression induces heme oxygenase 1 (HO-1) expression, which, as a key catalyst responsible for the oxidative degradation of heme, may inhibit the activities of the cytochrome P450 monooxygenases, thus substantially impairing testicular steroidogenesis. These results, coupled with the differential roles of mitogen-activated protein kinases and HO-1 signaling in spermatogenesis, lead us to propose a model in which a delicate balance between these two pathways modulated by the GGT5/oxidative stress cascade plays a central role during LH-stimulated steroidogenesis.


Assuntos
Dipeptidases/metabolismo , Estresse Oxidativo , Esteroides/biossíntese , Testículo/enzimologia , Testículo/patologia , gama-Glutamiltransferase/metabolismo , Animais , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Glutationa/deficiência , Glutationa/metabolismo , Heme Oxigenase-1/metabolismo , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/enzimologia , Células Intersticiais do Testículo/patologia , Hormônio Luteinizante/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Testosterona/deficiência , Regulação para Cima/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
3.
Front Cardiovasc Med ; 9: 821672, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35391838

RESUMO

Backgrounds and Objectives: Drug-coated balloons (DCBs) have shown promising benefits in improving the outcomes for patients with peripheral artery disease. Several randomized clinical trials have reported that paclitaxel-coated balloon significantly reduce the rates of restenosis and the need for reintervention in comparison with regular balloon angioplasty. Due to the differences in excipients, paclitaxel dose, and coating techniques, variable clinical outcomes have been observed with different DCBs. In this study, we aimed to evaluate the safety and efficacy of a novel ZENFlow carrier-free DCB in the treatment of femoropopliteal artery occlusive disease. Methods: In this randomized controlled trial conducted at 15 sites, 192 patients with Rutherford class 3-5 were randomly assigned into two groups: drug-coated balloon group and percutaneous transluminal angioplasty group. The primary endpoint was a late lumen loss at 6 months based on blinded angiographic core laboratory evaluations, and the secondary endpoints included primary patency rate, binary restenosis, clinically driven target lesion revascularization, ankle-brachial index, Rutherford class change, and major adverse events. Results: In this multicenter trial, 93 patients received DCB angioplasty, whereas 99 patients underwent regular balloon angioplasty. The late lumen loss at 6-month follow-up was 0.50 ± 0.82 and 1.69 ± 0.87 mm in the drug-coated balloon and percutaneous transluminal angioplasty groups, respectively (p < 0.001). During the 12-month follow-up period, the drug-coated balloon group showed a significantly higher primary patency rate (54 vs. 31.3%, p = 0.009) and markedly lower rates of target vessel restenosis (22.1 vs. 64.3%, p < 0.001) and clinically driven target lesion revascularization rate (5.4 vs. 19.2%, p = 0.006) than the percutaneous transluminal angioplasty group. Compared with the percutaneous transluminal angioplasty group, the drug-coated balloon group had significant improvements in the ankle-brachial index and Rutherford class. The all-cause mortality rate was comparable, and no device-related deaths occurred in either groups. Conclusions: Balloon angioplasty using a ZENFlow carrier-free drug-coated balloon is a safe and effective treatment method for femoropopliteal artery lesions. This novel drug-coated balloon catheter achieved satisfactory early and 1-year outcomes in this trial. Clinical Trial Registration: https://clinicaltrials.gov, identifier: NCT03844724.

4.
Chin Med J (Engl) ; 120(23): 2112-8, 2007 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-18167185

RESUMO

BACKGROUND: Histone deacetylase inhibitors (HDACIs) have been reported to induce apoptosis in cancer cells. The effects of trichostatin A (TSA) on gastric cancer cells have not been well characterized. This study was aimed to explore the effects and mechanisms of TSA on human gastric cancer SGC-7901 cells. METHODS: The cells were treated with TSA and analyzed by cell proliferation assay, Western blot, TUNEL assay, flow cytometry by fluorescein isothiocyanate (FITC) conjugated with Annexin V and PI staining, immunofluorescence analysis, analysis of subcellular fractionation, gene chips and real time polymerase chain reaction (PCR). RESULTS: TSA could inhibit cell growth and induced apoptosis in gastric cancer SGC-7901 cells through the regulation of apoptosis-related genes, such as Bcl-2, Bax and survivin. Further study indicated that the pan-caspase inhibitor z-VAD-fmk did not inhibit the apoptosis induced by TSA, and we did not observe the cleavage of poly ADP ribose polymerase (PARP) after TSA treatment too. In addition, apoptosis inducing factor (AIF) and EndoG were found to translocate from mitochondria to nucleus in the immunofluorescence assay and the Western analysis of subcellular fractionation confirmed the result of immunofluorescence assay. CONCLUSIONS: The apoptosis induced by TSA in gastric cancer SGC-7901 cells involves a caspase-independent pathway.


Assuntos
Apoptose/efeitos dos fármacos , Caspases/fisiologia , Inibidores Enzimáticos/farmacologia , Inibidores de Histona Desacetilases , Ácidos Hidroxâmicos/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Humanos , Proteínas Inibidoras de Apoptose , Proteínas Associadas aos Microtúbulos/análise , Proteínas de Neoplasias/análise , Proteínas Proto-Oncogênicas c-bcl-2/análise , Neoplasias Gástricas/patologia , Survivina , Proteína Supressora de Tumor p53/análise , Proteína Supressora de Tumor p53/fisiologia , Proteína X Associada a bcl-2/análise
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 66(4-5): 1194-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16959532

RESUMO

A new method for the determination of trace selenium based on solid substrate-room temperature phosphorimetry (SS-RTP) has been established. This method was based on the fact that in HCl-KCl buffer solution, potassium chlorate could oxidize phenyl hydrazine to form chloridize diazo-ion after being heated at 100 degrees C for 20 min, and then the diazo-ion reacted with 1,2-dihydroxynaphthalene-3,6-disulfonic acid to form red azo-compound which could emit strong room temperature phosphorescence (RTP) signal on filter paper. Selenium could catalyze potassium chlorate oxidizing the reaction between phenyl hydrazine and 1,2-dihydroxynaphthalene-3,6-disulfonic acid, which caused the sharp enhancement of SS-RTP. Under the optimum condition, the relationship between the phosphorescence emission intensity (DeltaIp) and the content of selenium obeyed Beer's law when the concentration of selenium is within the range of 1.60-320 fg spot-1 (or 0.0040-0.80 ng ml-1 with a sample volume of 0.4 microl). The regression equation of working curve can be expressed as DeltaIp=13.12+0.4839CSe(IV) (fg spot-1) (n=6), with correlation coefficient r=0.9991 and a detection limit of 0.28 fg spot-1 (corresponding to a concentration range of 7.0x10(-13) g ml-1 Se(IV), n=11). After 11-fold measurement, R.S.D. were 2.8 and 3.5% for the samples containing 0.0040 and 0.80 ng ml-1 of Se(IV), respectively. This accurate and sensitive method with good repeatability has been successfully applied to the determination of trace selenium in Chinese wolfberry and egg yolk with satisfactory results. The mechanism of the enhancement of phosphorescence was also discussed.


Assuntos
Cloratos/química , Hidrazinas/química , Medições Luminescentes/métodos , Naftalenos/química , Selênio/análise , Ácidos Sulfônicos/química , Temperatura , Oligoelementos/análise , Animais , Calibragem , Concentração de Íons de Hidrogênio , Lycium/química , Naftalenossulfonatos , Oxidantes , Oxirredução , Extratos Vegetais/química , Fatores de Tempo
6.
Clin Cancer Res ; 9(3): 1136-44, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12631619

RESUMO

Increased nuclear factor kappaB (NF-kappaB) activity is associated with increased tumor cell survival in multiple myeloma. The function of NF-kappaB is inhibited through binding to its inhibitor, IkappaB. Release of activated NF-kappaB follows proteasome-mediated degradation of IkappaB resulting from phosphorylation of the inhibitor and, finally, conjugation with ubiquitin. We report that myeloma cells have enhanced IkappaBalpha phosphorylation and increased NF-kappaB activity compared with normal hematopoietic cells. The proteasome inhibitor PS-341 blocked nuclear translocation of NF-kappaB, blocked NF-kappaB DNA binding, and demonstrated consistent antitumor activity against chemoresistant and chemosensitive myeloma cells. The sensitivity of chemoresistant myeloma cells to chemotherapeutic agents was markedly increased (100,000-1,000,000-fold) when combined with a noncytotoxic dose of PS-341 without affecting normal hematopoietic cells. Similar effects were observed using a dominant negative super-repressor for IkappaBalpha. Thus, these results suggest that inhibition of NF-kappaB with PS-341 may overcome chemoresistance and allow doses of chemotherapeutic agents to be markedly reduced with antitumor effects without significant toxicity.


Assuntos
Ácidos Borônicos/farmacologia , Complexos Multienzimáticos/antagonistas & inibidores , Mieloma Múltiplo/metabolismo , Pirazinas/farmacologia , Transporte Ativo do Núcleo Celular , Adenoviridae/genética , Antineoplásicos/farmacologia , Apoptose , Western Blotting , Bortezomib , Divisão Celular , Núcleo Celular/metabolismo , Sobrevivência Celular , Cisteína Endopeptidases , Citosol/metabolismo , Relação Dose-Resposta a Droga , Genes Dominantes , Humanos , Proteínas I-kappa B/metabolismo , Melfalan/farmacologia , Microscopia de Fluorescência , Inibidor de NF-kappaB alfa , NF-kappa B/metabolismo , Fosforilação , Complexo de Endopeptidases do Proteassoma , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologia , Fatores de Tempo , Transfecção , Células Tumorais Cultivadas , Ubiquitina/metabolismo
7.
Int J Clin Exp Med ; 8(10): 19642-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26770628

RESUMO

This study aims to evaluate the therapeutic results of percutaneous transhepatic embolization of gastroesophageal varices combined with partial splenic embolization in patients with liver cirrhosis, and to explore the role of this minimally invasive treatment as an alternative to surgery. 25 patients with liver cirrhosis were received percutaneous transhepatic embolization of gastroesophageal varices combined with partial splenic embolization. Another 25 patients with liver cirrhosis underwent Hassab's operation. They were followed up, and received endoscopy, B ultrasound, liver function and hematologic examination at 24 months after the therapy. In minimal invasive group, before treatment and after 24 month following up after treatment, improved varices, improved portal hypertension and improved hypersplenism were showed comparing with the surgery group, and that they were measured by endoscopic visualization, ultrasound and blood counts. the white blood cell and platelet count were 2.33±0.65 (10(9)/L) and 3.63±1.05 (10(10)/L), 7.98±3.0 (10(9)/L) and 16.3±9.10 (10(10)/L) (P<0.05); the diameter of the portal vein were 1.47±0.25 cm, 1.31±0.23 cm (P<0.05). Esophageal varices passed from grade III to lower grade II in 11 patients, and from grade II to lower grade I in 6 patients at 24 month following up. In surgical group, the white blood cell and platelet count were 2.2±0.60 (10(9)/L), 4.1±1.25 (10(10)/L) before treatment; 9.3±2.56 (10(9)/L), 32.1±12.47 (10(10)/L) after the treatment at 24 month following up (P<0.05). The diameter of the portal vein were 1.43±0.22 cm before the treatment and 1.28±0.18 cm after the treatment (P<0.05). Esophageal varices passed from grade III to lower grade II in 13 patients, and from grade II to lower grade I in 7 patients. The combination of PGEV and PSE can be considered as an option for the treatment of variceal bleeding with hypersplenism.

8.
PLoS One ; 10(7): e0131947, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26158267

RESUMO

BACKGROUND: Loss of functional allele for discoidin domain receptor 2 (Ddr2) results in impaired Leydig cell response to luteinizing hormone (LH), low testosterone production and arrested spermatogenesis in older male Ddr2slie/slie mice. However, the underlying mechanism responsible for this phenotype remains unknown. Herein, we reported for the first time that the deregulated expression of Ddr2 cognate ligand, namely collagen type I (COL1), may account for the disruption of the testicular steroidogenesis in Ddr2slie/slie mutant testes. METHODOLOGY/PRINCIPAL FINDINGS: Expression of Ddr2 increased gradually along postnatal development, whereas COL1 expression became negligible from adulthood onwards. In Ddr2slie/slie mutant testis, however, in contrast to the undetectable staining of Ddr2, COL1 expression was constantly detected, with the highest values detected during adulthood. In the experimental vasectomy model, Ddr2slie/slie mutant mice exhibited an early androgen deficiency than wild-type mice, along with the accumulation of fibrotic tissue in the interstitium. Functionally, ablation of endogenous Ddr2 resulted in a significant decrease of testosterone (T) level in TM3 cells in the presence of higher concentration of COL1 treatment. Conversely, overexpression of Ddr2 could help TM3 cells to maintain a normal testicular steroidogenesis even in the presence of high concentration of COL1. Additionally, attenuated expression of Ddr2 correlates to the deregulated level of serum T levels in human pathological testes. CONCLUSIONS: Abnormal accumulation of interstitial COL1 may be responsible for the steroidogenic dysfunction in Ddr2slie/slie mutant testes.


Assuntos
Receptores Proteína Tirosina Quinases/metabolismo , Receptores Mitogênicos/metabolismo , Testículo/patologia , Animais , Linhagem Celular , Colágeno Tipo I/metabolismo , Receptores com Domínio Discoidina , Modelos Animais de Doenças , Fibrose , Humanos , Imuno-Histoquímica , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia de Fluorescência , Oligospermia/metabolismo , Oligospermia/patologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Radioimunoensaio , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/genética , Receptores Mitogênicos/antagonistas & inibidores , Receptores Mitogênicos/genética , Síndrome de Células de Sertoli/metabolismo , Síndrome de Células de Sertoli/patologia , Testículo/metabolismo , Testosterona/sangue
9.
Cardiovasc Intervent Radiol ; 36(3): 764-72, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22869046

RESUMO

PURPOSE: This study evaluates the influence of transcatheter arterial infusion with heated saline on hepatic arterial and portal venous blood flows to tumor and normal hepatic tissues in a rabbit VX2 tumor model. METHODS: All animal experiments were approved by the institutional animal care and use committee. Twenty rabbits with VX2 liver tumors were divided into the following two groups: (a) the treated group (n = 10), which received a 60 mL transarterial injection of 60 °C saline via the hepatic artery; (b) the control group (n = 10), which received a 60 mL injection of 37 °C saline via the hepatic artery. Using ultrasonography, the blood flows in both the portal vein and hepatic artery were measured, and the changes in the hemodynamic indices were recorded before and immediately after the injection. The changes in the tumor and normal liver tissues of the two groups were histopathologically examined by hematoxylin and eosin staining after the injection. RESULTS: After the transcatheter arterial heated infusion, there was a decrease in the hepatic arterial blood flow to the tumor tissue, a significant decrease in the hepatic artery mean velocity (P < 0.05), and a significant increase in the resistance index (P < 0.05). On hematoxylin and eosin staining, there were no obvious signs of tissue destruction in the normal liver tissue or the tumor tissue after heated perfusion, and coagulated blood plasma was observed in the cavities of intratumoral blood vessels in the treated group. CONCLUSIONS: The changes in tumor blood flow in the rabbit VX2 tumor model were presumably caused by microthrombi in the tumor vessels, and the portal vein likely mediated the heat loss in normal liver tissue during the transarterial heated infusion.


Assuntos
Hipertermia Induzida , Circulação Hepática/efeitos dos fármacos , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Cloreto de Sódio/administração & dosagem , Angiografia , Animais , Meios de Contraste , Fluoroscopia , Artéria Hepática/diagnóstico por imagem , Infusões Intra-Arteriais , Iopamidol , Neoplasias Hepáticas Experimentais/diagnóstico por imagem , Masculino , Veia Porta/diagnóstico por imagem , Coelhos , Radiografia Intervencionista , Coloração e Rotulagem , Ultrassonografia
10.
PLoS One ; 6(10): e26013, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22022494

RESUMO

BACKGROUND: Deregulated thermal factors have been frequently implicated in the pathogenesis of male infertility, but the molecular basis through which certain responses are directed remain largely unknown. We previously reported that overexpression of exogenous Metastasis-associated protein 1 (MTA1) protects spermatogenic tumor cells GC-2spd (ts) against heat-induced apoptosis. To further dissect the underlying mechanism, we addressed here the fine coordination between MTA1 and p53 in pachytene spermatocytes upon hyperthermal stimulation. METHODOLOGY/PRINCIPAL FINDINGS: High level of MTA1 expression sustained for 1.5 h in primary spermatocytes after heat stress before a notable decrease was detected conversely correlated to the gradual increase of acetylation status of p53 and of p21 level. Knockdown of the endogenous MTA1 in GC-2spd (ts) elevated the acetylation of p53 by diminishing the recruitment of HDAC2 and thereafter led to a dramatic increase of apoptosis after heat treatment. Consistent with this, in vivo interference of MTA1 expression in the testes of C57BL/6 mice also urged an impairment of the differentiation of spermatocytes and a disruption of Sertoli cell function due to the elevated apoptotic rate after heat stress. Finally, attenuated expression of MTA1 of pachytene spermatocytes was observed in arrested testes (at the round spermatid level) of human varicocele patients. CONCLUSIONS: These data underscore a transient protective effect of this histone modifier in primary spermatocytes against heat-stress, which may operate as a negative coregulator of p53 in maintenance of apoptotic balance during early phase after hyperthermal stress.


Assuntos
Apoptose , Citoproteção , Resposta ao Choque Térmico , Histona Desacetilases/metabolismo , Estágio Paquíteno , Proteínas Repressoras/metabolismo , Espermatócitos/metabolismo , Fatores de Transcrição/metabolismo , Acetilação , Adulto , Animais , Histona Desacetilase 2/metabolismo , Humanos , Hipertermia Induzida , Imuno-Histoquímica , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Masculino , Camundongos , Modelos Biológicos , Espermatócitos/enzimologia , Espermatócitos/patologia , Espermatogênese , Temperatura , Testículo/metabolismo , Testículo/patologia , Tetraploidia , Transativadores , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima/genética
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