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1.
Insect Biochem Mol Biol ; 150: 103846, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36202385

RESUMO

Aphids feed on plant phloem sap that contains massive amounts of sucrose; this not only provides vital nutrition for the aphids but also produces high osmotic pressure. To utilize this carbon source and overcome the osmotic pressure, sucrose is hydrolyzed into the monosaccharides, glucose and fructose. In the green peach aphid (Myzus persicae), we show that this process is facilitated by a key α-glucosidase (MpAgC2-2), which is abundant in the aphid salivary gland and is secreted into leaves during feeding. MpAgC2-2 has a pH optimum of 8.0 in vitro, suggesting it has adapted to the environment of plant cells. Silencing MpAgC2-2 (but not the gut-specific MpAgC3-4) significantly increased the amount of sucrose ingested and hindered aphid feeding on the phloem of tobacco seedlings, resulting in a smaller body size, as well as lower α-glucosidase activity and glucose levels. These effects could be rescued by feeding aphids on tobacco plants transiently expressing MpAgC2-2. The transient expression of MpAgC2-2 also led to the hydrolysis of sucrose in tobacco leaves. Taken together, these results demonstrate that MpAgC2-2 is a salivary protein that facilitates extra-intestinal feeding via sucrose hydrolysis. Our findings provide insight into the ability of aphids to digest the high concentration of sucrose in phloem, and the underlying mechanism of extra-intestinal digestion.


Assuntos
Afídeos , Animais , Afídeos/genética , alfa-Glucosidases/genética , Saliva , Nicotiana , Sacarose , Glucose , Digestão
2.
Eur J Neurol ; 29(10): 2956-2966, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35748722

RESUMO

BACKGROUND AND PURPOSE: Multiple system atrophy (MSA) has no definitive genetic or environmental (G-E) risk factors, and the integrated effect of these factors on MSA etiology remains unknown. This study was undertaken to investigate the integrated effect of G-E factors associated with MSA and its subtypes, MSA-P and MSA-C. METHODS: A consecutive case-control study was conducted at two medical centers, and the interactions between genotypes of five previously reported susceptible single nucleotide polymorphisms (SNPs; SNCA_rs3857059, SNCA_rs11931074, COQ2_rs148156462, EDN1_rs16872704, MAPT_rs9303521) and graded exposure (never, ever, current) of four environmental factors (smoking, alcohol, drinking well water, pesticide exposure) were analyzed by a stepwise logistic regression model. RESULTS: A total of 207 MSA patients and 136 healthy controls were enrolled. In addition to SNP COQ2_rs148156462 (TT), MSA risk was correlated with G-E interactions, including COQ2_rs148156462 (Tc) × pesticide nonexposure, COQ2_rs148156462 (TT) × current smokers, SNCA_rs11931074 (tt) × alcohol nonusers, and SNCA_rs11931074 (GG) × well water nondrinkers (all p < 0.01), with an area under the receiver operating characteristic curve (AUC) of 0.804 (95% confidence interval [CI] = 0.671-0.847). Modulated risk of MSA-C, with MSA-P as a control, correlated with COQ2_rs148156462 (TT) × alcohol nondrinkers, SNCA_rs11931074 (GG) × well water ever drinkers, SNCA_rs11931074 (Gt) × well water never drinkers, and SNCA_rs3857059 (gg) × pesticide nonexposure (all p < 0.05), with an AUC of 0.749 (95% CI = 0.683-0.815). CONCLUSIONS: Certain COQ2 and SNCA SNPs interact with common environmental factors to modulate MSA etiology and subtype disposition. The mechanisms underlying the observed correlation between G-E interactions and MSA etiopathogenesis warrant further investigation.


Assuntos
Alquil e Aril Transferases/genética , Atrofia de Múltiplos Sistemas , Praguicidas , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos , Atrofia de Múltiplos Sistemas/genética , Atrofia de Múltiplos Sistemas/patologia , Água , alfa-Sinucleína/genética
3.
Clin Nucl Med ; 44(1): 75-77, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30358623

RESUMO

A 59-year-old woman presented with fever for 2 weeks. The patient had end-stage renal disease and was undergoing dialysis therapy for 10 years. Plain radiographs revealed extensive calcification in the subcutaneous tissues of the shoulders, thighs, and hips. In this case, TC-MDP bone scan detected all sites of subcutaneous metastatic calcification in one sweep. Ga-citrate scintigraphy was also performed and showed similar uptake at the same locations as those revealed by the bone scan, suggesting the existence of an inflammatory process at the sites of metastatic calcification.


Assuntos
Calcinose/diagnóstico por imagem , Radioisótopos de Gálio , Compostos Radiofarmacêuticos , Tela Subcutânea/diagnóstico por imagem , Medronato de Tecnécio Tc 99m , Feminino , Humanos , Pessoa de Meia-Idade , Cintilografia
4.
Biochem Biophys Res Commun ; 503(2): 1123-1129, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-29944884

RESUMO

Lung squamous cell carcinoma (LSCC) is a common type of non-small-cell lung cancer (NSCLC) and lacks effective treatment. Regorafenib, an oral multikinase inhibitor, has demonstrated promising anti-tumor activity in various solid tumors. To study whether regorafenib inhibits LSCC cells, we investigate the compound in several LSCC cell lines and explore the possible mechanism. In this study, we confirmed that regorafenib had anti-proliferation effect on LSCC cell lines by inducing G0/G1 arrest. In addition, glycogen synthase kinase 3ß (GSK3ß) remained at the same level and Ser9 phosphorylation of GSK3ß decreased with increasing incubation time and increasing regorafenib concentration in LSCC cells. GSK3ß inhibition enhanced the anti-tumor activity of regorafenib. Thus, GSK3ß activation restricted the anti-cancer effect of regorafenib on LSCC. In conclusion, regorafenib might be a promising drug for LSCC therapy. GSK3ß might be a potential target to increase the anti-tumor effect of regorafenib in LSCC cells.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Compostos de Fenilureia/farmacologia , Piridinas/farmacologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Fosforilação/efeitos dos fármacos
5.
Neurobiol Aging ; 50: 169.e3-169.e4, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27838047

RESUMO

Loss of function mutations in RAB39B were recently linked to X-linked recessive early-onset Parkinsonism with variable degrees of intellectual dysfunction. Postmortem examination of the brain biopsy from a patient carrying the gene deletion revealed widespread α-synuclein pathology. However, subsequent analyses reported conflict results to replicate the role of RAB39B mutations in patients with early-onset Parkinsonism. The aim of this study was to address the genetic contribution of RAB39B in early-onset and familial Parkinson's disease (PD) in a Taiwanese population. Among 466 subjects, we sequenced both the exons and exon-intron boundaries of RAB39B from 235 patients with early-onset PD (age of onset <50 years), 119 probands with familial PD, and 112 ethnicity-matched control subjects. We did not find any coding variants or previously reported mutations, suggesting that RAB39B mutations are not a common cause of early-onset or familial PD in our Taiwanese population.


Assuntos
Estudos de Associação Genética , Mutação , Doença de Parkinson/genética , Proteínas rab de Ligação ao GTP/genética , Adolescente , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/genética , Cromossomos Humanos X/genética , Estudos de Coortes , Éxons/genética , Feminino , Genes Recessivos , Humanos , Íntrons/genética , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/epidemiologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Taiwan/epidemiologia , Adulto Jovem , alfa-Sinucleína/metabolismo
6.
Hum Mol Genet ; 25(10): 1965-1978, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26931464

RESUMO

Parkinson's disease (PD) is a progressive neurodegenerative disorder that lacks a disease-modifying therapy. Leucine-rich repeat kinase 2 (LRRK2) was implicated as the most common genetic cause of PD. We previously established a LRRK2-G2019S Drosophila model that displayed the crucial phenotypes of LRRK2 parkinsonism. Here, we used a two-step approach to identify compounds from the FDA-approved licensed drug library that could suppress neurite degeneration in LRRK2-G2019S parkinsonism. Of 640 compounds, 29 rescued neurite degeneration phenotypes and 3 restored motor disability and dopaminergic neuron loss in aged LRRK2-G2019S flies. Of these three drugs, lovastatin had the highest lipophilicity, which facilitated crossing the blood-brain barrier. In LRRK2-G2019S knock-in mice and stably transfected human dopaminergic cells, lovastatin significantly rescued neurite degeneration in a dose-dependent manner, within a range of 0.05-0.1 µm The beneficial effect of lovastatin was exerted by activating anti-apoptotic Akt/Nrf signaling and decreasing caspase 3 levels. We also observed that lovastatin inhibited GSK3ß activity, a kinase downstream of Akt, by up-regulating GSK3ß (Ser9) phosphorylation. This inhibition subsequently decreased tau phosphorylation, which was linked to neuronal cytoskeleton instability. Conversely, pre-treatment with the Akt inhibitor, A6730, blocked the lovastatin-induced neuroprotective effect. The rescuing effects of lovastatin in dendritic arborization of LRRK2-G2019S neurons were abolished by co-expressing either a mutant allele of Akt (Akt104226) or a constitutively active form of GSK3ß (sggS9A). Our findings demonstrated that lovastatin restored LRRK2-G2019S neurite degeneration by augmenting Akt/NRF2 pathway and inhibiting downstream GSK3ß activity, which decreased phospho-tau levels. We suggested that lovastatin is a potential disease-modifying agent for LRRK2-G2019S parkinsonism.


Assuntos
Glicogênio Sintase Quinase 3 beta/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Degeneração Neural/tratamento farmacológico , Doença de Parkinson/genética , Proteínas Proto-Oncogênicas c-akt/genética , Serina Endopeptidases/genética , Animais , Animais Geneticamente Modificados , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , Drosophila melanogaster/genética , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Glicogênio Sintase Quinase 3 beta/biossíntese , Humanos , Lovastatina/administração & dosagem , Camundongos , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/patologia , Mutação , Degeneração Neural/genética , Degeneração Neural/patologia , Neuritos/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/patologia , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/genética , Transtornos Parkinsonianos/fisiopatologia , Transdução de Sinais/efeitos dos fármacos
7.
Neurobiol Aging ; 36(1): 546.e17-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25200193

RESUMO

A recent collaborative study that combined linkage analysis with whole-genome sequencing of family members of multiplex families with multiple system atrophy (MSA) has identified COQ2 gene as a causative gene for MSA. The common variant, c.T1178C (p.V393A, rs148156462), in the COQ2 gene was found to be associated with an increased risk of sporadic MSA. There is overlapping clinical characteristics between MSA and Parkinson's disease (PD), and the pathologic hallmark of both diseases is α-synucleinopathy. We therefore aim to analyze the COQ2 p.V393A variant in a large Taiwanese cohort with PD patients. We genotyped COQ2 p.V393A variant in a total of 1005 participants, comprising 500 patients with PD and 505 age/gender-matched control subjects. The frequency of TC/CC genotype was comparable between PD patients and control subjects (odds ratio: 0.81, 95% confidence interval: 0.42-1.56, p = 0.53). COQ2 p.V393A variant is not a genetic risk factor for PD, suggesting its specificity in disease susceptibility to MSA.


Assuntos
Alquil e Aril Transferases/genética , Variação Genética , Doença de Parkinson/genética , Idoso , Povo Asiático , Estudos de Coortes , Feminino , Ligação Genética , Predisposição Genética para Doença/genética , Técnicas de Genotipagem , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia de Múltiplos Sistemas/genética , Taiwan
8.
Parkinsonism Relat Disord ; 20(3): 280-3, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24342025

RESUMO

A recently published genome-wide association study in Caucasian and Asian populations showed a significant association between the bone marrow stromal cell antigen 1 (BST1) SNP rs11724635 and increased risk for Parkinson's disease (PD). To investigate whether BST1 rs11724635 increases the risk of PD, either by itself or in combination with environmental factors, we performed an association analysis of BST1 rs11724635 in a large cohort of Taiwanese patients with PD and age matched controls. The study used TaqMan genotyping, logistic regression, and haplotype methods. The genotype distribution of rs11724635 in PD patients (N = 468; p = 0.50) and control subjects (N = 487; p = 0.44) was consistent with Hardy-Weinberg equilibrium. Compared with the AA genotype, the frequency of both CA and CC genotypes was not significantly different between the patient and control groups. The adjusted odd ratios (ORs) for CA and CC were not statistically significant (CA: OR = 0.962, 95% CI = 0.643-1.439, p = 0.850; CC: OR = 0.992, 95% CI = 0.654-1.503, p = 0.969). Of note, ever use of well water before the onset of PD symptoms had an impact on the occurrence of PD through interactions with BST1 rs11724635 AC (OR = 1.453, p = 0.024) and CC (OR = 1.623, p = 0.008). Our results show that the BST1 rs11724635 polymorphism alone is not associated with the development of PD, but it can interact with well water drinking to increase the risk of PD in this Taiwanese population.


Assuntos
ADP-Ribosil Ciclase/genética , Antígenos CD/genética , Água Potável/efeitos adversos , Interação Gene-Ambiente , Predisposição Genética para Doença/genética , Doença de Parkinson/epidemiologia , Doença de Parkinson/genética , Idoso , Estudos de Casos e Controles , Feminino , Proteínas Ligadas por GPI/genética , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico , Polimorfismo Genético/genética , Fatores de Risco , Taiwan/epidemiologia
10.
Yao Xue Xue Bao ; 44(3): 288-95, 2009 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-19449526

RESUMO

Because c-Src and iNOS are key regulatory enzymes in tumorigenesis, a new series of 4-heterocycle amine-3-quinolinecarbonitriles as potent dual inhibitors of both enzymes were designed, synthesized and evaluated as multiple targets agents in cancer therapy. All compounds were evaluated by two related enzyme inhibition assays and an anti-proliferation assay in vitro. The results showed that most compounds inhibited c-Src and iNOS well. The best compound 33 inhibited both enzymes with the IC50 values of 0.0484 micromol x L(-1) and 34.5 micromol x (-1), respectively. Some of the compounds also showed moderate anti-proliferation activities at 10 micromol x L(-1) against colon cancer HT-29 and liver cancer HepG2 cell lines.


Assuntos
Compostos de Anilina , Antineoplásicos/síntese química , Desenho de Fármacos , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Quinolinas , Compostos de Anilina/síntese química , Compostos de Anilina/química , Compostos de Anilina/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Proteína Tirosina Quinase CSK , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Humanos , Óxido Nítrico Sintase Tipo II/metabolismo , Proteínas Tirosina Quinases/metabolismo , Quinolinas/síntese química , Quinolinas/química , Quinolinas/farmacologia , Quinases da Família src
12.
Bioorg Med Chem Lett ; 18(23): 6206-9, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18930653

RESUMO

Because both c-Src and iNOS are key regulatory enzymes in tumorigenesis, a new series of 4-heterocycle amine-3-quinolinecarbonitriles as potent dual inhibitors of both enzymes were designed, synthesized and evaluated as multiple targets agents in cancer therapy. All compounds were evaluated by two related enzyme inhibition assays and an anti-proliferation assay in vitro. The results showed that most compounds inhibited c-Src and iNOS well. The best compound 8 inhibited both enzymes with the IC(50) values of 34.8 nM and 26.7 microM. Several compounds also showed moderate anti-proliferation at 10 microM against colon and liver cancer cell lines.


Assuntos
Compostos de Anilina/síntese química , Compostos de Anilina/farmacologia , Antineoplásicos/síntese química , Desenho de Fármacos , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Nitrilas/síntese química , Nitrilas/farmacologia , Inibidores de Proteínas Quinases/síntese química , Proteínas Tirosina Quinases/antagonistas & inibidores , Quinolinas/síntese química , Quinolinas/farmacologia , Compostos de Anilina/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Proteína Tirosina Quinase CSK , Células HT29 , Humanos , Estrutura Molecular , Nitrilas/química , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Quinolinas/química , Relação Estrutura-Atividade , Quinases da Família src
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