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1.
FASEB J ; 37(8): e23075, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37432648

RESUMO

Stimulus-coupled insulin secretion from the pancreatic islet ß-cells involves the fusion of insulin granules to the plasma membrane (PM) via SNARE complex formation-a cellular process key for maintaining whole-body glucose homeostasis. Less is known about the role of endogenous inhibitors of SNARE complexes in insulin secretion. We show that an insulin granule protein synaptotagmin-9 (Syt9) deletion in mice increased glucose clearance and plasma insulin levels without affecting insulin action compared to the control mice. Upon glucose stimulation, increased biphasic and static insulin secretion were observed from ex vivo islets due to Syt9 loss. Syt9 colocalizes and binds with tomosyn-1 and the PM syntaxin-1A (Stx1A); Stx1A is required for forming SNARE complexes. Syt9 knockdown reduced tomosyn-1 protein abundance via proteasomal degradation and binding of tomosyn-1 to Stx1A. Furthermore, Stx1A-SNARE complex formation was increased, implicating Syt9-tomosyn-1-Stx1A complex is inhibitory in insulin secretion. Rescuing tomosyn-1 blocked the Syt9-knockdown-mediated increases in insulin secretion. This shows that the inhibitory effects of Syt9 on insulin secretion are mediated by tomosyn-1. We report a molecular mechanism by which ß-cells modulate their secretory capacity rendering insulin granules nonfusogenic by forming the Syt9-tomosyn-1-Stx1A complex. Altogether, Syt9 loss in ß-cells decreases tomosyn-1 protein abundance, increasing the formation of Stx1A-SNARE complexes, insulin secretion, and glucose clearance. These outcomes differ from the previously published work that identified Syt9 has either a positive or no effect of Syt9 on insulin secretion. Future work using ß-cell-specific deletion of Syt9 mice is key for establishing the role of Syt9 in insulin secretion.


Assuntos
Glucose , Insulina , Animais , Camundongos , Secreção de Insulina , Sinaptotagminas/genética , Sintaxina 1/genética , Proteínas do Tecido Nervoso , Proteínas R-SNARE/genética
2.
FASEB J ; 35(8): e21772, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34252225

RESUMO

Genetic deletion of Src associated in mitosis of 68kDa (Sam68), a pleiotropic adaptor protein prevents high-fat diet-induced weight gain and insulin resistance. To clarify the role of Sam68 in energy metabolism in the adult stage, we generated an inducible Sam68 knockout mice. Knockout of Sam68 was induced at the age of 7-10 weeks, and then we examined the metabolic profiles of the mice. Sam68 knockout mice gained less body weight over time and at 34 or 36 weeks old, had smaller fat mass without changes in food intake and absorption efficiency. Deletion of Sam68 in mice elevated thermogenesis, increased energy expenditure, and attenuated core-temperature drop during acute cold exposure. Furthermore, we examined younger Sam68 knockout mice at 11 weeks old before their body weights deviate, and confirmed increased energy expenditure and thermogenic gene program. Thus, Sam68 is essential for the control of adipose thermogenesis and energy homeostasis in the adult.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/deficiência , Metabolismo Energético , Termogênese , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Masculino , Camundongos , Camundongos Knockout , Proteínas de Ligação a RNA/metabolismo
3.
Am J Physiol Endocrinol Metab ; 319(5): E893-E903, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32954825

RESUMO

Saturated fatty acid (SFA) induces proinflammatory response through a Toll-like receptor (TLR)-mediated mechanism, which is associated with cardiometabolic diseases such as obesity, insulin resistance, and endothelial dysfunction. Consistent with this notion, TLR2 or TLR4 knockout mice are protected from obesity-induced proinflammatory response and endothelial dysfunction. Although SFA causes endothelial dysfunction through TLR-mediated signaling pathways, the mechanisms underlying SFA-stimulated inflammatory response are not completely understood. To understand the proinflammatory response in vascular endothelial cells in high-lipid conditions, we compared the proinflammatory responses stimulated by palmitic acid (PA) and other canonical TLR agonists [lipopolysaccharide (LPS), Pam3-Cys-Ser-Lys4 (Pam3CSK4), or macrophage-activating lipopeptide-2)] in human aortic endothelial cells. The expression profiles of E-selectin and the signal transduction pathways stimulated by PA were distinct from those stimulated by canonical TLR agonists. Inhibition of long-chain acyl-CoA synthetases (ACSL) by a pharmacological inhibitor or knockdown of ACSL1 blunted the PA-stimulated, but not the LPS- or Pam3CSK4-stimulated proinflammatory responses. Furthermore, triacsin C restored the insulin-stimulated vasodilation, which was impaired by PA. From the results, we concluded that PA stimulates the proinflammatory response in the vascular endothelium through an ACSL1-mediated mechanism, which is distinct from LPS- or Pam3CSK4-stimulated responses. The results suggest that endothelial dysfunction caused by PA may require to undergo intracellular metabolism. This expands the understanding of the mechanisms by which TLRs mediate inflammatory responses in endothelial dysfunction and cardiovascular disease.


Assuntos
Aorta/metabolismo , Coenzima A Ligases/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Inflamação/metabolismo , Ácido Palmítico/farmacologia , Aorta/efeitos dos fármacos , Selectina E/metabolismo , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Humanos , Insulina/farmacologia , Lipopolissacarídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Receptor 2 Toll-Like/agonistas , Receptor 4 Toll-Like/agonistas , Triazenos/farmacologia
4.
Br J Haematol ; 189(2): 303-312, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32012231

RESUMO

In the phase 3 study RERISE, patients with newly diagnosed chronic myeloid leukaemia in chronic phase demonstrated significantly faster and higher rates of major molecular response (MMR) with twice-daily radotinib 300 mg (n = 79) or 400 mg (n = 81) than with once-daily imatinib 400 mg (n = 81) after 12 months. With ≥48 months' follow-up, MMR was higher with radotinib 300 mg (86%) or 400 mg (83%) than with imatinib (75%). Among patients with BCR-ABL1 ≤ 10% at three months, MMR and molecular response 4·5 (MR4·5 ) were achieved within 48 months by more radotinib-treated patients (300 mg: 84% and 52%, respectively; 400 mg: 74% and 44%, respectively) than imatinib-treated patients (71% and 44%, respectively). Estimated overall and progression-free survival rates at 48 months were not significantly different between imatinib (94% and 94%, respectively) and radotinib 300 mg (99% and 97%, respectively) or 400 mg (95% and 93%, respectively). The treatment failure rate was significantly higher with imatinib (19%) than with radotinib 300 mg (6%; P = 0·0197) or 400 mg (5%; P = 0·0072). Safety profiles were consistent with previous reports; most adverse events occurred within 12 months. Radotinib continues to demonstrate robust, deep molecular responses, suggesting that treatment-free remission may be attainable.


Assuntos
Antineoplásicos/uso terapêutico , Benzamidas/uso terapêutico , Mesilato de Imatinib/uso terapêutico , Leucemia Mieloide de Fase Crônica/complicações , Leucemia Mieloide de Fase Crônica/tratamento farmacológico , Pirazinas/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacologia , Benzamidas/farmacologia , Feminino , Humanos , Mesilato de Imatinib/farmacologia , Masculino , Pessoa de Meia-Idade , Pirazinas/farmacologia , Resultado do Tratamento , Adulto Jovem
5.
Stem Cells ; 37(1): 77-88, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30281870

RESUMO

Mesenchymal stromal/stem cells (MSCs) have been developed as a promising source for cell-based therapies of ischemic disease. However, there are some hurdles in their clinical application such as poor cell engraftment and inconsistent stem cell potency. In this study, we sought to find biomarkers for predicting potency of MSCs for proangiogenic therapy to improve their beneficial effects. Large variations were observed in proangiogenic factor secretion profiles of conditioned media derived from nine different donor-derived Wharton's jelly (WJ)-derived MSCs and 8 factors among 55 angiogenesis-related factors were secreted at considerable levels. Two distinct WJ-MSCs that had the lowest or the highest secretion of these eight factors showed corresponding proangiogenic activities in in vitro angiogenesis assays. When four additional different donor-derived WJ-MSCs were further examined, proangiogenic activities in migration and tube formation of endothelial cells and in in vivo Matrigel plug assay were highly consistent with secretion levels of four major factors (angiogenin, interleukin-8, monocyte chemoattractant protein-1, and vascular endothelial growth factor). Such correlation was also observed in vascular regenerative effect in a mouse hind limb ischemia model. Blocking of these four factors by neutralizing antibodies or knockdown of them by siRNA treatment resulted in significant inhibition of proangiogenic activities of not only WJ-MSCs, but also bone marrow-derived MSCs. These results suggest that these four factors may represent efficient biomarkers for predicting vascular regenerative efficacy of MSCs. Stem Cells 2019;37:77-88.


Assuntos
Células-Tronco Mesenquimais/metabolismo , Neovascularização Fisiológica/genética , Comunicação Parácrina/genética , Animais , Diferenciação Celular , Humanos , Masculino , Camundongos
6.
J Biol Chem ; 293(47): 18086-18098, 2018 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-30228187

RESUMO

Secreted proteins are important metabolic regulators in both healthy and disease states. Here, we sought to investigate the mechanism by which the secreted protein complement 1q-like-3 (C1ql3) regulates insulin secretion from pancreatic ß-cells, a key process affecting whole-body glucose metabolism. We found that C1ql3 predominantly inhibits exendin-4- and cAMP-stimulated insulin secretion from mouse and human islets. However, to a lesser extent, C1ql3 also reduced insulin secretion in response to KCl, the potassium channel blocker tolbutamide, and high glucose. Strikingly, C1ql3 did not affect insulin secretion stimulated by fatty acids, amino acids, or mitochondrial metabolites, either at low or submaximal glucose concentrations. Additionally, C1ql3 inhibited glucose-stimulated cAMP levels, and insulin secretion stimulated by exchange protein directly activated by cAMP-2 and protein kinase A. These results suggest that C1ql3 inhibits insulin secretion primarily by regulating cAMP signaling. The cell adhesion G protein-coupled receptor, brain angiogenesis inhibitor-3 (BAI3), is a C1ql3 receptor and is expressed in ß-cells and in mouse and human islets, but its function in ß-cells remained unknown. We found that siRNA-mediated Bai3 knockdown in INS1(832/13) cells increased glucose-stimulated insulin secretion. Furthermore, incubating the soluble C1ql3-binding fragment of the BAI3 protein completely blocked the inhibitory effects of C1ql3 on insulin secretion in response to cAMP. This suggests that BAI3 mediates the inhibitory effects of C1ql3 on insulin secretion from pancreatic ß-cells. These findings demonstrate a novel regulatory mechanism by which C1ql3/BAI3 signaling causes an impairment of insulin secretion from ß-cells, possibly contributing to the progression of type 2 diabetes in obesity.


Assuntos
Proteínas do Sistema Complemento/metabolismo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Adipocinas , Animais , Linhagem Celular , Complemento C1q , Proteínas do Sistema Complemento/genética , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Glucose/metabolismo , Humanos , Secreção de Insulina , Proteínas do Tecido Nervoso/genética , Ratos
7.
Eur Radiol ; 29(9): 4593-4602, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30796567

RESUMO

OBJECTIVE: Chest pain is a common symptom in patients with hypertrophic cardiomyopathy (HCM), causing difficulty determining whether there is coexistent coronary artery disease (CAD). We investigated whether coronary computed tomography angiography (CCTA) can assess the prevalence and clinical significance of CAD in adult patients with HCM showing chest pain through longitudinal follow-up. METHODS: In 238 adult patients with HCM, who underwent CCTA for chest pain, we analyzed the degree of stenosis and adverse plaque characteristics (APCs) as CCTA variables. Three prediction models for adverse cardiovascular events (ACEs: all-cause mortality, myocardial infarction, unstable angina, heart failure, implantable cardioverter-defibrillator implantation, and stroke) were assessed using the combination of clinical risk factors, echocardiographic parameters, and CCTA variables. RESULTS: The prevalence of obstructive CAD (≥ 50% in luminal stenosis) and APC was 14.7% and 18.9%, respectively. During the follow-up period (median, 37 months; range, 2-108 months), there were 31 occurrences of ACEs (13.0%). Using multivariate Cox regression analysis, age, atrial fibrillation, low ejection fraction, obstructive CAD, and APCs were associated with ACEs (all p < 0.05). Among the prediction models for ACEs, the area under the curve (AUC) was higher (AUC = 0.92) when CCTA variables were added to the clinical (AUC = 0.84) and echocardiographic factors (AUC = 0.88) (p < 0.001). CONCLUSIONS: Using CCTA, about 20% of symptomatic HCM patients were associated with clinically significant atherosclerosis. Adding these CCTA variables to the clinical and echocardiographic variables may increase the predictions of ACEs; therefore, evaluating coronary atherosclerosis using CCTA may be helpful for symptomatic HCM patients. KEY POINTS: • Chest pain in adult patients with hypertrophic cardiomyopathy (HCM) remains challenging to distinguish from coronary artery disease. • Coronary computed tomography angiography (CCTA) can assess the severity and characteristics of coronary atherosclerosis in symptomatic HCM patients. • Adding CCTA variables to clinical and echocardiographic factors may increase the predictions of adverse cardiac events in HCM patients, and thus evaluating coronary atherosclerosis using CCTA may be helpful for HCM patients with chest pain.


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico por imagem , Doença da Artéria Coronariana/diagnóstico por imagem , Adulto , Idoso , Angina Instável/etiologia , Área Sob a Curva , Cardiomiopatia Hipertrófica/complicações , Dor no Peito/diagnóstico por imagem , Dor no Peito/etiologia , Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Doença da Artéria Coronariana/complicações , Estenose Coronária/complicações , Estenose Coronária/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Placa Aterosclerótica/complicações , Placa Aterosclerótica/diagnóstico por imagem , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/etiologia
8.
J Bacteriol ; 200(7)2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29339417

RESUMO

Septicemia-causing Vibrio vulnificus produces at least three exoproteases, VvpE, VvpS, and VvpM, all of which participate in interactions with human cells. Expression of VvpE and VvpS is induced in the stationary phase by multiple transcription factors, including sigma factor S, SmcR, and the cAMP-cAMP receptor protein (cAMP-CRP) complex. Distinct roles of VvpM, such as induction of apoptosis, lead us to hypothesize VvpM expression is different from that of the other exoproteases. Its transcription, which was found to be independent of sigma S, is induced at the early exponential phase and then becomes negligible upon entry into the stationary phase. SmcR and CRP were studied regarding the control of vvpM expression. Transcription of vvpM was repressed by SmcR and cAMP-CRP complex individually, which specifically bound to the regions -2 to +20 and +6 to +27, respectively, relative to the vvpM transcription initiation site. Derepression of vvpM gene expression was 10- to 40-fold greater in an smcR crp double mutant than in single-gene mutants. Therefore, these results show that the expression of V. vulnificus exoproteases is differentially regulated, and in this way, distinct proteases can engage in specific interactions with a host.IMPORTANCE An opportunistic human pathogen, Vibrio vulnificus produces multiple extracellular proteases that are involved in diverse interactions with a host. The total exoproteolytic activity is detected mainly in the supernatants of the high-cell-density cultures. However, some proteolytic activity derived from a metalloprotease, VvpM, was present in the supernatants of the low-cell-density cultures sampled at the early growth period. In this study, we present the regulatory mechanism for VvpM expression via repression by at least two transcription factors. This type of transcriptional regulation is the exact opposite of those for expression of the other V. vulnificus exoproteases. Differential regulation of each exoprotease's production then facilitates the pathogen's participation in the distinct interactions with a host.


Assuntos
Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Metaloendopeptidases/biossíntese , Metaloendopeptidases/genética , Percepção de Quorum , Vibrio vulnificus/genética , Apoptose , Proteína Receptora de AMP Cíclico/metabolismo , Repressão Enzimática/genética , Humanos , Proteólise , Fatores de Transcrição/genética , Vibrio vulnificus/enzimologia
9.
Hum Brain Mapp ; 39(4): 1596-1606, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29274110

RESUMO

To evaluate metabolic changes in the ipsi- and contralateral hemisphere in children showing a cognitive profile consistent with early reorganization of cognitive function, we evaluated the regional glucose uptake, interhemispheric metabolic connectivity, and cognitive function in children with unilateral SWS. Interictal 2-deoxy-2[18 F]fluoro-D-glucose (FDG)-PET scans of 27 children with unilateral SWS and mild epilepsy and 27 age-matched control (non-SWS children with epilepsy and normal FDG-PET) were compared using statistical parametric mapping (SPM). Regional FDG-PET abnormalities calculated as SPM(t) scores in the SWS group were correlated with cognitive function (IQ) in left- and right-hemispheric subgroups. Interhemispheric metabolic connectivity between homotopic cortical regions was also calculated. Verbal IQ was substantially (≥10 points difference) higher than non-verbal IQ in 61% of the right- and 71% of the left-hemispheric SWS group. FDG SPM(t) scores in the affected hemisphere showed strong positive correlations with IQ in the left-hemispheric, but not in right-hemispheric SWS group in several frontal, parietal, and temporal cortical regions. Significant positive interhemispheric metabolic connectivity, present in controls, was diminished in the SWS group. In addition, the left-hemispheric SWS group showed inverse metabolic interhemispheric correlations in specific parietal, temporal, and occipital regions. FDG SPM(t) scores in the same regions of the right (unaffected) hemisphere showed inverse correlations with IQ. These findings suggest that left-hemispheric lesions in SWS often result in early reorganization of verbal functions while interfering with ("crowding") their non-verbal cognitive abilities. These cognitive changes are associated with specific metabolic abnormalities in the contralateral hemisphere not directly affected by SWS.


Assuntos
Encéfalo/metabolismo , Cognição/fisiologia , Síndrome de Sturge-Weber/metabolismo , Síndrome de Sturge-Weber/psicologia , Adolescente , Encéfalo/diagnóstico por imagem , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Fluordesoxiglucose F18 , Lateralidade Funcional , Glucose , Humanos , Inteligência/fisiologia , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/metabolismo , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Síndrome de Sturge-Weber/diagnóstico por imagem , Síndrome de Sturge-Weber/tratamento farmacológico
10.
Acta Haematol ; 140(3): 146-156, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30253397

RESUMO

BACKGROUND: The neutrophil-to-lymphocyte ratio (NLR) is an independent prognostic marker in solid and hematological cancers. While the derived NLR (dNLR) was shown to be non-inferior to the NLR in large cohorts of patients with different cancer types, it has not been validated as a prognostic marker for multiple myeloma (MM) to date. METHODS: Between May 22, 2011 and May 29, 2014, 176 patients with MM from 38 centers who were ineligible for autologous stem cell transplantation were analyzed. The dNLR was calculated using complete blood count differential data. The optimal dNLR cut-off value according to receiver operating characteristic analysis of overall survival (OS) was 1.51. All patients were treated with melphalan and prednisone combined with bortezomib. RESULTS: The complete response rate was lower in the high dNLR group compared to the low dNLR group (7 vs. 26.1%, respectively; p = 0.0148); the corresponding 2-year OS rates were 72.2 and 84.7%, respectively (p = 0.0354). A high dNLR was an independent poor prognostic factor for OS (hazard ratio 2.217, 95% CI 1.015-4.842; p = 0.0458). CONCLUSION: The dNLR is a readily available and cheaply obtained parameter in clinical studies, and shows considerable potential as a new prognostic marker for transplantation-ineligible patients with MM.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Linfócitos/citologia , Mieloma Múltiplo/terapia , Neutrófilos/citologia , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Área Sob a Curva , Intervalo Livre de Doença , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC , Transplante Autólogo
11.
Asian-Australas J Anim Sci ; 31(3): 429-438, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29502392

RESUMO

OBJECTIVE: Although the efficacy of Rubus coreanus (RC) byproducts as a feed additive has been recognized, its effects on intestinal microorganisms and the immune system are still unknown. METHODS: Six-week-old male rats were treated with 0.5% RC (T1), 1.0% RC (T2), and 1.5% RC (T3) for 4 weeks. RESULTS: We found that treatment with RC byproducts significantly increased the daily gain of body weight and feed intake. Treg-cell differentiation was enhanced in the mesenteric lymph nodes and spleen from the rats fed with RC byproducts. Illumina sequencing showed that bacteria in the phylum Firmicutes decreased and while those in the phylum Bacteroidetes increased in RC-treated groups. Particularly, the pathogenic microorganisms in the family Peptococcaceae decreased, and the non-pathogenic families Lachnospiraceae and S24-7 increased. Quantitative polymerase chain reaction analysis showed that the RC byproducts increased the lactic acid bacteria Bifidobacterium spp., Oscillospira spp., Leuconostoc citreum, and Weissella cibaria in a concentration-dependent manner. CONCLUSION: RC byproducts may be effective in immunomodulation by affecting intestinal microorganisms.

12.
Mol Microbiol ; 97(2): 330-46, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25869813

RESUMO

An exoprotease of Vibrio vulnificus, VvpS, exhibits an autolytic function during the stationary phase. To understand how vvpS expression is controlled, the regulators involved in vvpS transcription and their regulatory mechanisms were investigated. LeuO was isolated in a ligand-fishing experiment, and experiments using a leuO-deletion mutant revealed that LeuO represses vvpS transcription. LeuO bound the extended region including LeuO-binding site (LBS)-I and LBS-II. Further screening of additional regulators revealed that SmcR and cyclic adenosine monophosphate-receptor protein (CRP) play activating roles in vvpS transcription. SmcR and CRP bound the regions overlapping LBS-I and -II, respectively. In addition, the LeuO occupancy of LBS-I and LBS-II was competitively exchanged by SmcR and CRP, respectively. To examine the mechanism of stationary-phase induction of vvpS expression, in vivo levels of three transcription factors were monitored. Cellular level of LeuO was maximal at exponential phase, while those of SmcR and CRP were maximal at stationary phase and relatively constant after the early-exponential phase, respectively. Thus, vvpS transcription was not induced during the exponential phase by high cellular content of LeuO. When entering the stationary phase, however, LeuO content was significantly reduced and repression by LeuO was relieved through simultaneous binding of SmcR and CRP to LBS-I and -II, respectively.


Assuntos
Exopeptidases/biossíntese , Fatores de Transcrição/metabolismo , Vibrio vulnificus/metabolismo , Proteínas de Bactérias/metabolismo , Indução Enzimática , Exopeptidases/genética , Exopeptidases/metabolismo , Regulação Bacteriana da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Ligação Proteica , Serina Proteases/biossíntese , Serina Proteases/genética , Serina Proteases/metabolismo , Vibrio vulnificus/enzimologia , Vibrio vulnificus/genética , Vibrio vulnificus/crescimento & desenvolvimento
13.
Haematologica ; 101(6): 717-23, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26888022

RESUMO

The aim of the Korean Imatinib Discontinuation Study was to identify predictors for safe and successful imatinib discontinuation. A total of 90 patients with a follow-up of ≥12 months were analyzed. After a median follow-up of 26.6 months after imatinib discontinuation, 37 patients lost the major molecular response. The probability of sustained major molecular response at 12 months and 24 months was 62.2% and 58.5%, respectively. All 37 patients who lost major molecular response were retreated with imatinib therapy for a median of 16.9 months, and all achieved major molecular response again at a median of 3.9 months after resuming imatinib therapy. We observed newly developed or worsened musculoskeletal pain and pruritus in 27 (30%) patients after imatinib discontinuation. Imatinib withdrawal syndrome was associated with a higher probability of sustained major molecular response (P=0.003) and showed a trend for a longer time to major molecular response loss (P=0.098). Positivity (defined as ≥ 17 positive chambers) of digital polymerase chain reaction at screening and longer imatinib duration before imatinib discontinuation were associated with a higher probability of sustained major molecular response. Our data demonstrated that the occurrence of imatinib withdrawal syndrome after imatinib discontinuation and longer duration of imatinib were associated with a lower rate of molecular relapse. In addition, minimal residual leukemia measured by digital polymerase chain reaction had a trend for a higher molecular relapse. (Trial registered at ClinicalTrials.gov: NCT01564836).


Assuntos
Antineoplásicos/uso terapêutico , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Neoplasia Residual/diagnóstico , Inibidores de Proteínas Quinases/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Feminino , Seguimentos , Proteínas de Fusão bcr-abl/genética , Humanos , Mesilato de Imatinib/administração & dosagem , Mesilato de Imatinib/efeitos adversos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/genética , Reação em Cadeia da Polimerase , Prognóstico , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/efeitos adversos , Recidiva , Retratamento , Fatores de Tempo , Resultado do Tratamento
14.
Epilepsia ; 57(1): 51-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26662710

RESUMO

OBJECTIVE: We aimed to compare the efficacy, safety, and tolerability of a modified Atkins diet (MAD) with the classic ketogenic diet (KD) for the treatment of intractable childhood epilepsy. METHODS: From March 2011 to March 2014, 104 patients aged 1-18 years who had refractory epilepsy were randomly assigned to each diet group (ClinicalTrials.gov, number NCT2100501). A seizure diary record was used to compare seizure frequencies with the baseline prediet seizure frequency at the third and sixth months after diet therapy initiation. RESULTS: Fifty-one patients were assigned to the KD and 53 patients to the MAD. The KD group had a lower mean percentage of baseline seizures compared with the MAD group at 3 months (38.6% for KD, 47.9% for MAD) and 6 months (33.8% for KD, 44.6% for MAD), but the differences were not statistically significant (95% confidence interval [CI] 24.1-50.8, p = 0.291 for 3 months; 95% CI 17.8-46.1, p = 0.255 for 6 months). Instead, for patients aged 1-2 years, seizure outcomes were consistently much more favorable in patients consuming the KD compared with those consuming the MAD. The rate of seizure freedom at 3 months after diet therapy initiation was significantly higher (53% for KD, 20% for MAD, p = 0.047) in these patients. The MAD had advantages with respect to better tolerability and fewer serious side effects. SIGNIFICANCE: The MAD might be considered as the primary choice for the treatment of intractable epilepsy in children, but the classic KD is more suitable as the first line of diet therapy in patients <2 years of age.


Assuntos
Dieta com Restrição de Carboidratos/métodos , Dieta Cetogênica/métodos , Epilepsia Resistente a Medicamentos/dietoterapia , Adolescente , Criança , Pré-Escolar , Método Duplo-Cego , Epilepsia Resistente a Medicamentos/sangue , Feminino , Seguimentos , Humanos , Lactente , Corpos Cetônicos/sangue , Masculino , Resultado do Tratamento
15.
Acta Haematol ; 135(3): 133-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26535871

RESUMO

BACKGROUND: Imatinib mesylate (IM) discontinuation is under active investigation in chronic myeloid leukemia-chronic phase (CML-CP) patients with undetectable minimal residual disease (UMRD). However, limited data exist on the long-term outcomes following IM discontinuation in patients treated with frontline IM therapy. METHODS: We consecutively enrolled patients with CML-CP who discontinued IM after achieving UMRD for ≥12 months between June 2009 and January 2013. RESULTS: Nineteen patients (8 male, 11 female) were included. After IM discontinuation, 14 patients (74%) lost UMRD after a median of 4.0 months. Of the 14 patients with molecular relapses, 12 (86%) relapsed within the first 9 months after IM discontinuation and 2 (14%) relapsed at 20.5 and 22.8 months, respectively. No molecular relapse was observed after 2 years of IM discontinuation. With a median follow-up of 58.1 months (range 23.0-66.5), the estimated UMRD persistence rate at 5 years was 23.7%. IM was readministered in all patients with molecular relapse, and 12 patients (86%) reachieved UMRD at a median of 5.3 months. A high-risk Sokal score, delayed UMRD achievement and short-term IM therapy were significantly associated with molecular relapse. CONCLUSION: These findings suggest that IM discontinuation in patients who achieved UMRD after frontline IM therapy resulted in favorable long-term outcomes in terms of safety and feasibility.


Assuntos
Antineoplásicos/uso terapêutico , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Neoplasia Residual/diagnóstico , Inibidores de Proteínas Quinases/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Feminino , Seguimentos , Proteínas de Fusão bcr-abl/genética , Humanos , Mesilato de Imatinib/administração & dosagem , Mesilato de Imatinib/efeitos adversos , Incidência , Estimativa de Kaplan-Meier , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mieloide de Fase Crônica/tratamento farmacológico , Leucemia Mieloide de Fase Crônica/genética , Leucemia Mieloide de Fase Crônica/patologia , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/tratamento farmacológico , Neoplasia Residual/epidemiologia , Prognóstico , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/efeitos adversos , Recidiva , Retratamento , Estudos Retrospectivos , Resultado do Tratamento
16.
Am J Physiol Endocrinol Metab ; 309(9): E767-76, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26522062

RESUMO

Impairment of vasodilator action of insulin is associated with endothelial dysfunction and insulin resistance. Activation of Toll-like receptor 4 (TLR4) induces proinflammatory response and endoplasmic reticulum (ER) stress. Saturated fatty acids (SFA) activate TLR4, which induces ER stress and endothelial dysfunction. Therefore, we determined whether TLR4-mediated ER stress is an obligatory step mediating SFA-induced endothelial dysfunction. Palmitate stimulated proinflammatory responses and ER stress, and this was suppressed by knockdown of TLR4 in primary human aortic endothelial cells (HAEC). Next, we examined the role of TLR4 in vasodilatory responses in intact vessels isolated from wild-type (WT, C57BL/6) and TLR4-KO mice after feeding high-fat (HFD) or normal chow diet (NCD) for 12 wk. Arterioles isolated from HFD WT mice exhibited impaired insulin-stimulated vasodilation compared with arterioles isolated from NCD WT mice. Deficiency of TLR4 was protective from HFD-induced impairment of insulin-stimulated vasodilation. There were no differences in acetylcholine (Ach)- or sodium nitroprusside (SNP)-stimulated vasodilation between the two groups. Furthermore, we examined whether ER stress is involved in SFA-induced impairment of vasodilator actions of insulin. Infusion of palmitate showed the impairment of vasodilatory response to insulin, which was ameliorated by coinfusion with tauroursodeoxycholic acid (TUDCA), an ER stress suppressor. Taken together, the results suggest that TLR4-induced ER stress may be an obligatory step mediating the SFA-mediated endothelial dysfunction.


Assuntos
Estresse do Retículo Endoplasmático , Insulina/farmacologia , Receptor 4 Toll-Like/fisiologia , Vasodilatação , Animais , Bovinos , Células Cultivadas , Dieta Hiperlipídica/efeitos adversos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/genética , Endotélio Vascular/efeitos dos fármacos , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Palmitatos/farmacologia , Receptor 4 Toll-Like/genética , Vasodilatação/efeitos dos fármacos , Vasodilatação/genética , Vasodilatadores/farmacologia
17.
Hepatology ; 59(5): 1912-20, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23907815

RESUMO

UNLABELLED: Our goal was to determine whether single-nucleotide polymorphisms (SNPs) of telomere maintenance genes influence the development and clinical outcomes of patients with hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC). We evaluated 20 SNPs of five telomere maintenance genes in 702 patients with HCC and 351 hepatitis B virus surface antigen-positive controls without HCC. Significant SNPs were then validated in an independent cohort of 857 HCC patients and 429 controls. We assessed the association of each SNP with the development of HCC and overall survival through a multivariate Cox proportional analysis. A significantly increased risk of HCC development was identified for the telomerase-associated protein 1 (TEP1) rs1713449 SNP in both the discovery and replication phases (combined odds ratio = 1.42, P = 9.378 × 10(-5) ). In addition, the TEP1 rs1713449, TEP1 rs872072, protection of telomeres 1 homolog rs7784168, telomerase reverse transcriptase rs13167280, and telomeric repeat binding factor 1 rs2306494 SNPs had a significant effect on the overall survival, and a similar survival effect was validated in the replication cohort. Moreover, there was a significant dose-dependent association between the number of putatively high-risk genotypes of the five aforementioned SNPs and overall survival. The median survival time was significantly prolonged for patients with HCC with two or fewer putatively high-risk genotypes versus those with three or more high-risk genotypes (85 versus 44 months, log-rank P = 4.483 × 10(-5) ), and this was demonstrated in the replication cohort (52 versus 37 months, log-rank P = 0.026). CONCLUSION: These observations suggest that the SNPs of telomere maintenance genes play a potential role in the development of HCC and the survival of HCC patients with chronic HBV infections.


Assuntos
Carcinoma Hepatocelular/genética , Hepatite B Crônica/complicações , Neoplasias Hepáticas/genética , Polimorfismo de Nucleotídeo Único , Telômero , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , Proteínas de Transporte/genética , Feminino , Genótipo , Humanos , Neoplasias Hepáticas/mortalidade , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Proteínas de Ligação a RNA , Complexo Shelterina , Proteínas de Ligação a Telômeros/genética
18.
Ann Hematol ; 94(11): 1845-51, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26251158

RESUMO

There is no standard salvage chemotherapy for relapsed or refractory peripheral T-cell lymphomas (PTCLs). Gemcitabine combined with cisplatin has been known as an effective regimen for lymphoma treatment in the salvage setting. We investigated the efficacy and toxicity of gemcitabine, dexamethasone, and cisplatin (GDP) for relapsed or refractory PTCLs in search of a more effective and less toxic therapy. Patients with relapsed or refractory PTCLs with more than one previous regimen were eligible. Treatment consisted of gemcitabine 1000 mg/m(2) intravenously (i.v.) on days 1 and 8, dexamethasone 40 mg orally on days 1-4, and cisplatin 70 mg/m(2) i.v. on day 1, and then every 21 days. Patients could proceed to autologous stem cell transplantation (ASCT) after four cycles of GDP or receive up to six treatment cycles. Twenty-five eligible patients were evaluated for toxicity and response. The diagnoses of participants included 14 cases of PTCL-not otherwise specified (NOS) (56 %) and four cases of angioimmunoblastic T-cell lymphoma (16 %) among others. The median age of the patients was 59 years (range 20-75 years). After treatments with GDP, which delivered a median of four GDP cycles, there were 12 patients with complete responses (CR; 48 %) and six with partial responses (PR; 24 %). The overall response rate (RR) was 72 %. Four patients preceded to ASCT, and three patients finally achieved CR. The median progression free survival was 9.3 months (95 % confidence interval (CI); 4.1-14.6) with a median follow-up duration of 27.1 months. In a total of 86 cycles of GDP, grade 3 or 4 neutropenia and thrombocytopenia occurred in 16.3 and 12.8 % of cycles, respectively. Three patients (3.3 %) experienced febrile neutropenia. GDP is a highly effective and optimal salvage regimen for relapsed or refractory PTCLs and can be administered with acceptable toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Desoxicitidina/análogos & derivados , Linfoma de Células T Periférico/tratamento farmacológico , Linfoma de Células T Periférico/mortalidade , Terapia de Salvação/métodos , Adulto , Idoso , Cisplatino/uso terapêutico , Terapia Combinada , Desoxicitidina/uso terapêutico , Dexametasona/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Terapia de Salvação/efeitos adversos , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
19.
J Clin Gastroenterol ; 49(8): e76-81, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25319734

RESUMO

GOAL AND BACKGROUND: Host genetic diversity may play roles in development of HCC. This study was conducted to validate the effects of tumor necrosis factor-alpha (TNF-α) gene polymorphism on development of hepatocellular carcinoma (HCC) in patients chronically infected with hepatitis B virus (HBV). STUDY: The study cohort comprised 224 patients with HBV-associated HCC and 206 with HBV-associated liver cirrhosis (LC). Using chromosomal DNA, TNF-α promoter gene polymorphisms were determined at 3 common single-nucleotide polymorphism (SNP) sites (TNF-α-1031 T>C, TNF-α-857 C>T, and TNF-α-308 G>A) using a single base extension method. The genotype distributions were compared between the 2 groups. All the HBV-associated LC patients were followed up regularly every 6 to 12 months for surveillance of HCC development. RESULTS: In the cross-sectional analysis, the frequency of TNF-α-857 T allele was much higher in patients with HCC compared with those with LC (42% vs. 31%, P<0.01). Of 206 HBV-associated LC patients, 12 (5.8%) developed HCC during the median follow-up period of 36 months. The cumulative occurrence rates of HCC were significantly higher in patients with TNF-α-857 T allele than those withTNF-α-857 C/C genotype (1-, 3-, and 5-y rates: 2.9%, 12.8%, and 20.7% vs. 0%, 3.1%, and 5.3%, respectively; P=0.013). However, the other genetic polymorphisms of TNF-α promoter gene did not affect the development of HCC. In multivariate analysis, TNF-α-857 T allele was a significant predictor of HCC development (hazard ratio 6.29, P=0.01). CONCLUSION: Our data suggest that TNF-α-857 T allele is closely associated with development of HCC in HBV-associated LC patients.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Hepatite B Crônica/complicações , Neoplasias Hepáticas/epidemiologia , Fator de Necrose Tumoral alfa/genética , Adulto , Idoso , Carcinoma Hepatocelular/virologia , Estudos Transversais , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Vírus da Hepatite B/isolamento & purificação , Humanos , Cirrose Hepática/epidemiologia , Cirrose Hepática/virologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Adulto Jovem
20.
J Biol Chem ; 288(31): 22693-705, 2013 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-23754277

RESUMO

Epigallocatechin gallate (EGCG) is a major polyphenol in green tea that has beneficial effects in the prevention of cardiovascular disease. Autophagy is a cellular process that protects cells from stressful conditions. To determine whether the beneficial effect of EGCG is mediated by a mechanism involving autophagy, the roles of the EGCG-stimulated autophagy in the context of ectopic lipid accumulation were investigated. Treatment with EGCG increased formation of LC3-II and autophagosomes in primary bovine aortic endothelial cells (BAEC). Activation of calmodulin-dependent protein kinase kinase ß was required for EGCG-induced LC3-II formation, as evidenced by the fact that EGCG-induced LC3-II formation was significantly impaired by knockdown of calmodulin-dependent protein kinase kinase ß. This effect is most likely due to cytosolic Ca(2+) load. To determine whether EGCG affects palmitate-induced lipid accumulation, the effects of EGCG on autophagic flux and co-localization of lipid droplets and autophagolysosomes were examined. EGCG normalized the palmitate-induced impairment of autophagic flux. Accumulation of lipid droplets by palmitate was markedly reduced by EGCG. Blocking autophagosomal degradation opposed the effect of EGCG in ectopic lipid accumulation, suggesting the action of EGCG is through autophagosomal degradation. The mechanism for this could be due to the increased co-localization of lipid droplets and autophagolysosomes. Co-localization of lipid droplets with LC3 and lysosome was dramatically increased when the cells were treated with EGCG and palmitate compared with the cells treated with palmitate alone. Collectively, these findings suggest that EGCG regulates ectopic lipid accumulation through a facilitated autophagic flux and further imply that EGCG may be a potential therapeutic reagent to prevent cardiovascular complications.


Assuntos
Autofagia/efeitos dos fármacos , Catequina/análogos & derivados , Endotélio Vascular/efeitos dos fármacos , Metabolismo dos Lipídeos , Adenilato Quinase/metabolismo , Animais , Sequência de Bases , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Catequina/farmacologia , Bovinos , Células Cultivadas , Primers do DNA , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo
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