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1.
Mol Neurobiol ; 60(4): 1826-1835, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36580198

RESUMO

Bone marrow-derived neural stem cells (BM-NSCs) have shed light on novel therapeutic approaches for PD with the potential to halt or even reverse disease progression. Various strategies have been developed to promote therapeutic efficacy via optimizing implanted cells and the microenvironment of transplantation in the central nervous system (CNS). This current study further proved that the combination of fasudil, a Rho-kinase inhibitor, and BM-NSCs exhibited a synergetic effect on restoring neuron loss in the MPTP-PD mice model. It simultaneously unveiled cellular mechanisms underlying synergistic neuron-protection effects of fasudil and BM-NSCs, which included promoting the proliferation, and migration of endogenous NSCs, and contributing to microglia shift into the M2 phenotype. Corresponding molecular mechanisms were observed, including the inhibition of inflammatory responses, the elevation of neurotrophic factors, and the induction of WNT/ß-catenin and PI3K/Akt/mTOR signaling pathways. Our study provides evidence for the co-intervention of BM-NSCs and fasudil as a promising therapeutic method with enhanced efficacy in treating neurodegenerative diseases.


Assuntos
Células-Tronco Neurais , Doença de Parkinson , Camundongos , Animais , Doença de Parkinson/metabolismo , Medula Óssea , Fosfatidilinositol 3-Quinases/metabolismo , Neurônios , Células-Tronco Neurais/metabolismo , Células da Medula Óssea
2.
Eur J Med Chem ; 226: 113887, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34624824

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disorder. Early diagnosis is the key to treatment but is still a great challenge in the clinic now. The discovery of alpha-synuclein (α-syn) aggregates ligands has become an attractive strategy to meet the early diagnosis of PD. Herein, we designed and synthesized a series of styrylaniline derivatives as novel α-syn aggregates ligands. Several compounds displayed good potency to α-syn aggregates with Kd values less than 0.1 µM. The docking study revealed that the hydrogen bonds and cation-pi interaction between ligands and α-syn aggregates would be crucial for the activity. The representative compound 7-16 not only detected α-syn aggregates in both SH-SY5Y cells and brain tissues prepared from two kinds of α-syn preformed-fibrils-injected mice models but also showed good blood-brain barrier penetration characteristics in vivo with a brain/plasma ratio over 1.0, which demonstrates its potential as a lead compound for further development of in vivo imaging agents.


Assuntos
Compostos de Anilina/farmacologia , Descoberta de Drogas , Doença de Parkinson/tratamento farmacológico , alfa-Sinucleína/antagonistas & inibidores , Compostos de Anilina/síntese química , Compostos de Anilina/química , Animais , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Estrutura Molecular , Doença de Parkinson/diagnóstico , Doença de Parkinson/metabolismo , Agregados Proteicos/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , alfa-Sinucleína/metabolismo
3.
Neurotherapeutics ; 18(2): 962-978, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33723752

RESUMO

Glucagon-like peptide-1 (GLP-1) receptor stimulation ameliorates parkinsonian motor and non-motor deficits in both experimental animals and patients; however, the disease-modifying mechanisms of GLP-1 receptor activation have remained unknown. The present study investigated whether exendin-4 (a GLP-1 analogue) can rescue motor deficits and exert disease-modifying effects in a parkinsonian rat model of α-synucleinopathy. This model was established by unilaterally injecting AAV-9-A53T-α-synuclein into the right substantia nigra pars compacta, followed by 4 or 8 weeks of twice-daily intraperitoneal injections of exendin-4 (5 µg/kg/day) starting at 2 weeks after AAV-9-A53T-α-synuclein injections. Positron emission tomography/computed tomography (PET/CT) scanning and immunostaining established that treatment with exendin-4 attenuated tyrosine-hydroxylase-positive neuronal loss and terminal denervation and mitigated the decrease in expression of vesicular monoamine transporter 2 within the nigrostriatal dopaminergic systems of rats injected with AAV-9-A53T-α-synuclein. It also mitigated the parkinsonian motor deficits assessed in behavioral tests. Furthermore, through both in vivo and in vitro models of Parkinson's disease, we showed that exendin-4 promoted autophagy and mediated degradation of pathological α-synuclein, the effects of which were counteracted by 3-methyladenine or chloroquine, the autophagic inhibitors. Additionally, exendin-4 attenuated dysregulation of the PI3K/Akt/mTOR pathway in rats injected with AAV-9-A53T-α-synuclein. Taken together, our results demonstrate that exendin-4 treatment relieved behavioral deficits, dopaminergic degeneration, and pathological α-synuclein aggregation in a parkinsonian rat model of α-synucleinopathy and that these effects were mediated by enhanced autophagy via inhibiting the PI3K/Akt/mTOR pathway. In light of the safety and tolerance of exendin-4 administration, our results suggest that exendin-4 may represent a promising disease-modifying treatment for Parkinson's disease.


Assuntos
Autofagia/efeitos dos fármacos , Exenatida/uso terapêutico , Neuroproteção/efeitos dos fármacos , Transtornos Parkinsonianos/prevenção & controle , Sinucleinopatias/prevenção & controle , alfa-Sinucleína/toxicidade , Animais , Autofagia/fisiologia , Linhagem Celular Tumoral , Exenatida/farmacologia , Feminino , Humanos , Neuroproteção/fisiologia , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/patologia , Ratos , Ratos Sprague-Dawley , Sinucleinopatias/induzido quimicamente , Sinucleinopatias/patologia
4.
J Parkinsons Dis ; 10(3): 969-979, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32568105

RESUMO

BACKGROUND: Parkinson's disease (PD) is the second most common neurodegenerative disorder, but the disease-modifying therapies focusing on the core pathological changes are still unavailable. Rho-associated protein kinase (ROCK) has been suggested as a promising target for developing neuroprotective therapies in PD. OBJECTIVE: We aimed to explore the promotion of α-synuclein (α-syn) clearance in a rat model. METHODS: In a rat model induced by unilateral injection of adeno-associated virus of serotype 9 (AAV9) expressing A53T α-syn (AAV9-A53T-α-syn) into the right substantia nigra, we aimed to investigate whether Fasudil could promote α-syn clearance and thereby attenuate motor impairments and dopaminergic deficits. RESULTS: In our study, treatment with Fasudil (5 mg/kg rat weight/day) for 8 weeks significantly improved the motor deficits in the Cylinder and Rotarod tests. In the in vivo positron emission tomography imaging with the ligand 18F-dihydrotetrabenazine, Fasudil significantly enhanced the dopaminergic imaging in the injected striatum of the rat model (p < 0.05 vs. vehicle group, p < 0.01 vs. left striatum in Fasudil group). The following mechanistic study confirmed that Fasudil could promote the autophagic clearance of α-syn by Becline 1 and Akt/mTOR pathways. CONCLUSION: Our study suggested that Fasudil, the ROCK2 inhibitor, could attenuate the anatomical and behavioral lesions in the Parkinsonian rat model by autophagy activation. Our results identify Fasudil as a drug with high translational potential as disease-modifying treatment for PD and other synucleinopathies.


Assuntos
Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Doença de Parkinson/metabolismo , alfa-Sinucleína/metabolismo , Animais , Autofagia/fisiologia , Modelos Animais de Doenças , Feminino , Doenças Neurodegenerativas/metabolismo , Doença de Parkinson/tratamento farmacológico , Ratos Sprague-Dawley , Substância Negra/metabolismo , Substância Negra/patologia
5.
Clin Immunol ; 203: 142-153, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31078707

RESUMO

Aberrant ROCK activation has been found in patients with several autoimmune diseases, but the role of ROCK in myasthenia gravis (MG) has not yet been clearly investigated. Here, we demonstrated that ROCK activity was significantly higher in peripheral blood mononuclear cells (PBMCs) from MG patients. ROCK inhibitor Fasudil down-regulated the proportions of Th1 and Th17 cells in PBMCs of MG patients in vitro. Intraperitoneal injection of Fasudil ameliorated the severity of experimental autoimmune myasthenia gravis (EAMG) rats and restored the balance of Th1/Th2/Th17/Treg subsets. Furthermore, Fasudil inhibited the proliferation of antigen-specific Th1 and Th17 cells, and inhibited CD4 + T cells differentiated into Th1 and Th17 through decreasing phosphorylated Stat1 and Stat3, but promoted Treg cell differentiation through increasing phosphorylated Stat5. We conclude that dysregulated ROCK activity may be involved in the pathogenic immune response of MG and inhibition of ROCK activity might serve as a novel treatment strategy for MG.


Assuntos
Miastenia Gravis/imunologia , Fator de Transcrição STAT5/metabolismo , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th17/imunologia , Quinases Associadas a rho/metabolismo , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Feminino , Homeostase , Humanos , Fosforilação , Ratos , Ratos Endogâmicos Lew , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT3/metabolismo , Quinases Associadas a rho/antagonistas & inibidores
6.
Mol Med Rep ; 18(5): 4417-4427, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30221704

RESUMO

Ginkgolide B (GB) and ginkgolide K (GK) are two main active monomers of ginkgolides that present a unique group of diterpenes found naturally in the leaves of the Ginkgo biloba tree. Astrocytes are the most abundant cell type within the central nervous system (CNS) and serve essential roles in maintaining healthy brain function. The present study compared the biological effects of GB and GK on astrocytes exposed to oxygen­glucose deprivation (OGD). The results demonstrated that GB and GK exhibit many different actions. The level of the platelet­activating factor (PAF) was elevated on astrocytes exposed to OGD, and inhibited by GB and GK treatment. Although GB and GK inhibited the expression of p­NF­κB/p65, GK exerted stronger anti­inflammatory and antioxidant effects on astrocytes exposed to OGD than GB by inhibiting interleukin (IL)­6 and tumor necrosis factor­α, and inducing IL­10 and the nuclear factor­erythroid 2­related factor 2/HO­1 signaling pathway. When compared with GB treatment, GK treatment maintained high levels of phosphoinositide 3­kinase/phosphorylated­protein kinase B expression, and induced a marked upregulation of Wnt family member 1 and brain derived neurotrophic factor, indicating that GK, as a natural plant compound, may have more attractive prospects for clinical application in the treatment of neurological disorders than GB.


Assuntos
Antioxidantes/administração & dosagem , Ginkgolídeos/administração & dosagem , Lactonas/administração & dosagem , Doenças do Sistema Nervoso/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Animais , Antioxidantes/química , Apoptose/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Astrócitos/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Ginkgo biloba/química , Glucose/metabolismo , Humanos , Interleucina-10/genética , Camundongos , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/patologia , Oxigênio/metabolismo , Fosfatidilinositol 3-Quinases/genética , Extratos Vegetais/química , Fator de Ativação de Plaquetas/genética , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA/genética
7.
J Environ Pathol Toxicol Oncol ; 37(2): 93-101, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30055545

RESUMO

The combination approach is now a well-established treatment for cancer. The present study evaluated the potential of curcumin and resveratrol on p53 post-translational modifications during gastric cancer. We segregated rats into five groups that included normal controls, dimethylhydrazine (DMH) treated, DMH + curcumin treated, DMH + resveratrol treated, and DMH + curcumin + resveratrol treated. Morphological analyses of tumor nodules confirmed carcinogenesis in rats after 25 weeks of DMH administration. The DMH treatment significantly induced carcinogenesis, as evidenced by high tumor burden in DMH-treated rats compared with controls. Moreover, DMH treatment caused a significant increase in the protein expressions of p53 as well as p53 phosphorylation in the DMH-treated rats. In addition, a significant rise was observed in 14C glucose uptake and 3H-thymidin uptakes in DMH-treated rats. Furthermore, enzyme activities of lactate dehydrogenase and alkaline phosphatase also showed a significant rise. On the contrary, significant decline was noticed in the p53 acetylation at residue 382 of DMH-treated rats. Conversely, combined treatment with curcumin and resveratrol to DMH-treated rats resulted in significant moderation in the tumor burden. In addition, a significant rise in p53 acetylation was at residue 382 of DMH-treated rats after treatment with phytochemicals. Supplementation with phytochemicals significantly modulated other biophysical and biochemical indices to near normal levels. Therefore, we conclude that curcumin and resveratrol significantly modulated p53 post-translational modifications during gastric cancer.


Assuntos
Antineoplásicos/farmacologia , Curcumina/farmacologia , Processamento de Proteína Pós-Traducional , Estilbenos/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Proteína Supressora de Tumor p53/genética , Acetilação , Animais , Antineoplásicos Fitogênicos/farmacologia , Carcinogênese , Dimetilidrazinas/farmacologia , Combinação de Medicamentos , Masculino , Fosforilação , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Resveratrol , Neoplasias Gástricas/etiologia , Proteína Supressora de Tumor p53/metabolismo
8.
Mol Oncol ; 11(5): 455-469, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28156061

RESUMO

Zinc finger protein X-linked (ZFX) is frequently upregulated in multiple human malignancies and also plays a critical role in the maintenance of self-renewal in embryonic stem cells. However, the role of ZFX in liver cancer stem cells (CSCs) remains obscure. We observed that the elevated expression of both ZFX and epithelial cell adhesion molecule (EpCAM) was associated with aggressive clinicopathological features and indicated poor prognosis in patients with hepatocellular carcinoma (HCC). ZFX was commonly enriched in liver EpCAM+ CSCs. Knockdown of ZFX decreased the proportion of EpCAM+ CSCs in HCC cells and suppressed their expression of stemness-related genes, self-renewal capacity, chemoresistance, metastatic potential, and tumorigenicity. Conversely, upregulation of ZFX in CSCs rescued these inhibitory effects and enhanced stem-like properties. Mechanistically, depletion of ZFX reduced nuclear translocation and transactivation of ß-catenin, thereby inhibiting the self-renewal capacity of EpCAM+ CSCs. Moreover, knockdown of ß-catenin attenuated the self-renewal of EpCAM+ HCC cells stably expressing ZFX, further indicating that ß-catenin is required for ZFX-mediated expansion and maintenance of EpCAM+ CSCs. Taken together, our findings indicate that ZFX activates and maintains EpCAM+ liver CSCs by promoting nuclear translocation and transactivation of ß-catenin. Furthermore, combination of ZFX and EpCAM may serve as a significant indicator for prognosis of patients with HCC.


Assuntos
Carcinoma Hepatocelular/patologia , Molécula de Adesão da Célula Epitelial/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Neoplasias Hepáticas/patologia , Células-Tronco Neoplásicas/metabolismo , Dedos de Zinco , Idoso , Análise de Variância , Animais , Carcinoma Hepatocelular/metabolismo , Autorrenovação Celular/fisiologia , Resistencia a Medicamentos Antineoplásicos , Molécula de Adesão da Célula Epitelial/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Estimativa de Kaplan-Meier , Fatores de Transcrição Kruppel-Like/genética , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/patologia , Prognóstico , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/genética , beta Catenina/metabolismo
9.
J Mol Neurosci ; 58(2): 193-200, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26411568

RESUMO

During immuno-mediated demyelinating lesions, endocannabinoid system participates in both inflammatory and neurodegenerative damage through several mechanisms that involve neuronal and immune cells. Here, we constructed lentiviral vector to upregulate CB1 receptor (CB1R) in the lumbar spinal cord 5-6 region and observe the effect of clinical score and possible mechanism on the occurrence and development of experimental autoimmune encephalomyelitis (EAE). The results show that overexpression of CB1R delayed the onset of clinical signs and ameliorated the severity of disease. Overexpression of CB1R significantly inhibited the expression of NF-kB/p65 and TLR-4 as well as levels of IL-1ß, IL-6, and TNF-α, followed by a decrease of IL-17 and an increase of IL-10 in the spinal cord of mice. The percentage of M1 marker CD11b(+)CD16/32(+) cells was decreased, while the percentage of M2 marker CD11b(+)CD206(+) and CD11b(+)IL-10(+) cells was elevated in splenic mononuclear cells (MNCs) of mice with overexpression of CB1R. Interestingly, overexpression of CB1R dramatically enhanced the expression of neurotrophic NT-3, BDNF, and GDNF in the spinal cord. These results indicate that local overexpression of CB1R in the spinal cord exhibited neuroprotective effects in EAE, mainly suppressing inflammatory microenvironment and elevating neurotrophic factors, slightly declining IL-1ß and IL-17 in the spleen, and increased IL-10 in the brain. Its complexity remains to be carefully considered and further studied in further investigation.


Assuntos
Encefalomielite Autoimune Experimental/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Regulação para Cima , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Células Cultivadas , Feminino , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Neurotrofina 3/genética , Neurotrofina 3/metabolismo , Receptor CB1 de Canabinoide/genética , Medula Espinal/metabolismo , Baço/citologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
10.
Mol Neurobiol ; 53(4): 2258-68, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25972237

RESUMO

The accumulation of misfolded α-synuclein in dopamine (DA) neurons is believed to be of major importance in the pathogenesis of Parkinson's disease (PD). Animal models of PD, based on viral-vector-mediated over-expression of α-synuclein, have been developed and show evidence of dopaminergic toxicity, providing us a good tool to investigate potential therapies to interfere with α-synuclein-mediated pathology. An efficient disease-modifying therapeutic molecule should be able to interfere with the neurotoxicity of α-synuclein aggregation. Our study highlighted the ability of an autophagy enhancer, trehalose (at concentrations of 5 and 2% in drinking water), to protect against A53T α-synuclein-mediated DA degeneration in an adeno-associated virus serotype 1/2 (AAV1/2)-based rat model of PD. Behavioral tests and neurochemical analysis demonstrated a significant attenuation in α-synuclein-mediated deficits in motor asymmetry and DA neurodegeneration including impaired DA neuronal survival and DA turnover, as well as α-synuclein accumulation and aggregation in the nigrostriatal system by commencing 5 and 2% trehalose at the same time as delivery of AAV. Trehalose (0.5%) was ineffective on the above behavioral and neurochemical deficits. Further investigation showed that trehalose enhanced autophagy in the striatum by increasing formation of LC3-II. This study supports the concept of using trehalose as a novel therapeutic strategy that might prevent/reverse α-synuclein aggregation for the treatment of PD.


Assuntos
Comportamento Animal/efeitos dos fármacos , Dependovirus/metabolismo , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Trealose/uso terapêutico , alfa-Sinucleína/metabolismo , Animais , Autofagia/efeitos dos fármacos , Glicemia/metabolismo , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , Extremidades/patologia , Feminino , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Doença de Parkinson/sangue , Ratos Sprague-Dawley , Solubilidade , Substância Negra/efeitos dos fármacos , Substância Negra/patologia , Trealose/farmacologia , Tirosina 3-Mono-Oxigenase/metabolismo
11.
Int J Clin Exp Pathol ; 7(9): 5988-96, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25337243

RESUMO

UNLABELLED: Hepatocellular carcinoma (HCC) is one of the most malignant tumors worldwide, especially in Eastern China where HBV infection confirmed as the most important pathological element. HBV X gene, extremely easy to mutate and integrate into hepatocytes, plays a significant role in HBV infection and HCC development. We deduced that mutations of integrated HBx gene make transformation more malignant. The aim of the study was to investigate whether there were different mutation patterns between the HCC tissues and the pericarcinoma liver tissues (PCLT) from patients with HCC in Eastern China. METHODS: HBx genes extracted from 287 HCC tissue samples and 195 PCLT tissue samples were analyzed by sequence alignment and stratified analysis with the matched medical records. RESULTS: Mutations occurred complicated and changeable in both HCC and PCLT. COOH-terminal truncation is more frequently found in HCC than PCLT (P < 0.05). There is no single site mutation of nucleic acid or amino acid makes distribution discrepancy between HCC and PCLT. Hydrophobic/hydrophilic character of amino acid of site 43, 47, 127, 131, 132 make distribution discrepancy between HCC and PCLT in men when stratified for gender (P < 0.05). Hydrophobic/hydrophilic character of amino acid of site 40 makes distribution discrepancy between HCC and PCLT in both male and female (P < 0.05). Hydrophobic/hydrophilic character of amino acid of site 47 and 127 make significant discrepancy among clinical stage I, II, III (P < 0.05). CONCLUSIONS: During the infection and replication of HBV, HBx mutates to adjust itself to the hepatocyte and increase the carcinogenesis. COOH-terminal truncated HBX may play a stimulative role in HBV-related HCC carcinogenesis as well as hydrophobic/hydrophilic character changes in some specific amino acid sites.


Assuntos
Vírus da Hepatite B/genética , Hepatite B/virologia , Neoplasias Hepáticas/virologia , Fígado/virologia , Mutação , Transativadores/genética , Sequência de Aminoácidos , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/patologia , Transformação Celular Viral , China/epidemiologia , Análise Mutacional de DNA , DNA Viral/genética , Feminino , Genótipo , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Vírus da Hepatite B/patogenicidade , Humanos , Interações Hidrofóbicas e Hidrofílicas , Fígado/patologia , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/patologia , Masculino , Estadiamento de Neoplasias , Fenótipo , Fatores de Risco , Análise de Sequência de Proteína , Transativadores/química , Proteínas Virais Reguladoras e Acessórias , Replicação Viral
12.
Mol Cell Proteomics ; 12(8): 2236-48, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23665501

RESUMO

Paclitaxel, a natural antitumor compound, is produced by yew trees at very low concentrations, causing a worldwide shortage of this important anticancer medicine. These plants also produce significant amounts of 7-ß-xylosyl-10-deacetyltaxol, which can be bio-converted into 10-deacetyltaxol for the semi-synthesis of paclitaxel. Some microorganisms can convert 7-ß-xylosyl-10-deacetyltaxol into 10-deacetyltaxol, but the bioconversion yield needs to be drastically improved for industrial applications. In addition, the related ß-xylosidases of these organisms have not yet been defined. We set out to discover an efficient enzyme for 10-deacetyltaxol production. By combining the de novo sequencing of ß-xylosidase isolated from Lentinula edodes with RT-PCR and the rapid amplification of cDNA ends, we cloned two cDNA variants, Lxyl-p1-1 and Lxyl-p1-2, which were previously unknown at the gene and protein levels. Both variants encode a specific bifunctional ß-d-xylosidase/ß-d-glucosidase with an identical ORF length of 2412 bp (97% identity). The enzymes were characterized, and their 3.6-kb genomic DNAs (G-Lxyl-p1-1, G-Lxyl-p1-2), each harboring 18 introns, were also obtained. Putative substrate binding motifs, the catalytic nucleophile, the catalytic acid/base, and potential N-glycosylation sites of the enzymes were predicted. Kinetic analysis of both enzymes showed kcat/Km of up to 1.07 s(-1)mm(-1) against 7-ß-xylosyl-10-deacetyltaxol. Importantly, at substrate concentrations of up to 10 mg/ml (oversaturated), the engineered yeast could still robustly convert 7-ß-xylosyl-10-deacetyltaxol into 10-deacetyltaxol with a conversion rate of over 85% and a highest yield of 8.42 mg/ml within 24 h, which is much higher than those reported previously. Therefore, our discovery might lead to significant progress in the development of new 7-ß-xylosyl-10-deacetyltaxol-converting enzymes for more efficient use of 7-ß-xylosyltaxanes to semi-synthesize paclitaxel and its analogues. This work also might lead to further studies on how these enzymes act on 7-ß-xylosyltaxanes and contribute to the growing database of glycoside hydrolases.


Assuntos
Cogumelos Shiitake/enzimologia , Taxoides/metabolismo , Xilosidases/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , DNA Fúngico/genética , Proteínas Fúngicas/genética , Dados de Sequência Molecular , RNA Fúngico/genética , Cogumelos Shiitake/genética , Xilosidases/genética , Leveduras/genética , Leveduras/metabolismo
13.
Dig Dis Sci ; 57(11): 2901-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22615019

RESUMO

BACKGROUND: Our previous work revealed transforming growth factor beta1 (TGFß1) gene polymorphisms are associated with susceptibility to hepatocellular carcinoma and liver cirrhosis. However, no further study of functional substitution in hepatic cells has yet been reported. AIMS: This study was designed to uncover the functional mechanisms of TGFß1 gene polymorphisms in the pathogenesis of liver diseases. METHODS: Two recombinant TGFß1 expression plasmids containing TGFß1 codon 10 Leu/Pro variation were constructed with CMV promoter and transfected into human hepatoma cell lines (HepG2 and SMMU 7721), hepatic stellate cells (LX-2), and immortalized hepatocytes (L02). The secretion capacities of TGFß1 protein in the transfected cells were determined by ELISA. Apoptosis, proliferative activity, and expression of CD 105, CD83, and CD80 were also measured by use of flow cytometry. RESULTS: The ELISA results showed that cells transfected with CMV-Pro10 were more capable of TGFß1 secretion than those transfected with CMV-Leu10. Functionally, CMV-Pro10 was more apoptosis-protective and induced more proliferation than CMV-Leu10 in transfected hepatic cells. Pro10 up-regulated expression of CD105 and down-regulated expression of CD83. CONCLUSIONS: TGFß1 gene Leu10Pro variation in signal peptide has significant effects on TGFß1 secretion and functions in hepatic cells.


Assuntos
Hepatócitos/metabolismo , Polimorfismo de Nucleotídeo Único , Fator de Crescimento Transformador beta1/genética , Antígenos CD/metabolismo , Apoptose , Linhagem Celular , Linhagem Celular Tumoral , Códon , Primers do DNA , Regulação para Baixo , Endoglina , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulinas/metabolismo , Glicoproteínas de Membrana/metabolismo , Plasmídeos , Regiões Promotoras Genéticas , Receptores de Superfície Celular/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Transfecção , Fator de Crescimento Transformador beta1/metabolismo , Regulação para Cima , Antígeno CD83
14.
Yao Xue Xue Bao ; 47(10): 1389-93, 2012 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-23289154

RESUMO

Codon bias is an important factor which influences heterologous gene expression. Optimizing codon sequence could improve expression level of heterologous gene. In order to improve the expression level of BmK AngM1 gene encoding the analgesic peptide from Buthus martensii Karsch in Pichia pastoris, the codon-optimized BmK AngM1 gene according to its cDNA sequence and the preference codon usage of P. pastoris were cloned into expression vector pPIC9K and then transformed into P. pastoris. The expersion of recombinant BmK AngM1 (rBmK AngM1) was inducced by methanol in the medium, and the expression level of the optimized BmK AngM1 gene was 3.7 times of the native one. These results suggested that the expression of BmK AngM1 in P. pastoris could be successfully improved by codon optimization.


Assuntos
Códon/genética , Pichia/metabolismo , Venenos de Escorpião/genética , Escorpiões/química , Sequência de Aminoácidos , Animais , Expressão Gênica , Pichia/genética , Plasmídeos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Venenos de Escorpião/isolamento & purificação , Venenos de Escorpião/metabolismo , Transformação Genética
15.
Zhonghua Fu Chan Ke Za Zhi ; 45(4): 292-7, 2010 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-20646543

RESUMO

OBJECTIVE: To investigate the expression of exogenous gene transferred by piggyBac (PB) transposon in various gynecological malignant cell lines and reveal its potential application of gene therapy in gynecological cancer. METHODS: Amplified herpes simplex virus thymidine kinase (HSV-tk) gene coding region by PCR and integrated it into PB expression vector, PB[Act-RFP]DS, for reconstructing PB[Act-RFP, HSV-tk]DS (pPB/TK). By using different transfection reagents: FuGENE HD, jetPEI, lipofectamine 2000, pPB/TK together with helper plasmid Act-PBase were cotransfected into four mostly common gynecological malignant tumor cell lines HeLa, JEG-3, SKOV3 and HEC-1B. The mRFP1 report gene expressions was observed and detected by fluorescence microscope and flow cytometry to analyze transfection efficiency. The expressions of HSV-tk and mRFP1 gene were detected by reverse transcription PCR (RT-PCR). The cytotoxic effect of various concentration of pro-drug ganciclovir (GCV) for transfected cells was detected by methyl thiazole tetrazolium assay. The transfected cells were positive sorted by flow cytometry and limiting diluted to obtain the stable transfected cell line. The insertion sites of foreign gene transferred by PB transposon in genome were analyzed by inverse PCR. RESULTS: (1) Double digests analysis and sequences test demonstrated that pPB/TK vector was reconstructed successfully. (2) Using three different transfective reagents, PB transposon transferred HSV-tk gene and mRFP1 gene into HeLa, HEC-1B, SKOV3 and JEG-3 cell efficiently, and the transfection efficiency of pPB/TK for the same cell was different by using different transfective reagents; in Hela cell, the transfection efficiency of FuGENE HD [(78.7+/-9.2)%] was higher than that of lipofectamine 2000 [(54.1+/-11.4)%] and jetPEI [(46.5+/-7.4)%, all P<0.05]; using the same transfective reagent, the transfection efficiency of pPB/TK was also different on various cell lines, using FuGENE HD, the transfection efficiency of pPB/TK on HeLa, JEG-3 and SKOV3 cell was (78.7+/-9.2)%, (74.4+/-8.9)% and (83.2+/-9.7)% respectively, which all were higher than that on HEC-1B [(39.5+/-8.7)%, P<0.05]. (3) RT-PCR showed that there were the mRNA expression of HSV-tk and mRFP1 in all cell lines. (4) 50% inhibitory concentration of GCV for transfected cells, HeLa, JEG-3, SKOV3 and HEC-1B, was 1.29, 3.35, 0.09 and 13.28 microg/ml respectively. Inhibitory effect of GCV (10 microg/ml) on SKOV3 transfected with pPB/TK was (86+/-9)%, which was superior to that transfected with pORF-HSVtk alone [(52+/-12)%, P<0.05]. (5) The insertion sites of PB transposon in the target cells genome were located at TTAA sites. mRFP1 expression still could be detected in three months after transfected. CONCLUSIONS: PB transposon could transfer exogenous gene into various gynecological malignant cells, which could integrated into genome and obtain a long-term and stable expression. It is expected that PB transposon may supply a more efficient and safer transgene technology platform for gene therapy in gynecological cancer.


Assuntos
Elementos de DNA Transponíveis/genética , Técnicas de Transferência de Genes , Vetores Genéticos , Proteínas Luminescentes/genética , Timidina Quinase/genética , Sobrevivência Celular , Feminino , Citometria de Fluxo , Ganciclovir/administração & dosagem , Ganciclovir/farmacologia , Expressão Gênica , Terapia Genética , Neoplasias dos Genitais Femininos/genética , Neoplasias dos Genitais Femininos/metabolismo , Neoplasias dos Genitais Femininos/terapia , Células HeLa , Humanos , Proteínas Luminescentes/metabolismo , Plasmídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Simplexvirus/genética , Simplexvirus/metabolismo , Timidina Quinase/metabolismo , Transfecção , Transgenes , Proteína Vermelha Fluorescente
16.
Yi Chuan ; 30(9): 1097-107, 2008 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-18779165

RESUMO

The septins are a family of proteins that are broadly distributed in almost all of eukaryotes except plants. septin was first identified in yeast as a protein that played a role in cytokinesis. With the recent advances in the field, the functions of these proteins become diverse in many organisms. In particular, the number of known mammalian septin family members has increased dramatically. They are now known to have many cellular roles such as cytokinesis, polarity determination, vesicle trafficking and membrane dynamics. Recently, more and more data suggest that some septin family members participate in the pathogenesis of different diseases including neoplasia, neurodegeneration and infections. These make the research of septins a hallmark in cell biology and pathology. In this review, we will summarize the major research progresses about septins in their classification, structure, biological function and the relationship with human diseases.


Assuntos
Proteínas do Citoesqueleto/fisiologia , Exocitose/fisiologia , Proteínas Fúngicas/fisiologia , GTP Fosfo-Hidrolases/química , Animais , Transformação Celular Neoplásica/metabolismo , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/classificação , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Imunofluorescência , Proteínas Fúngicas/química , Proteínas Fúngicas/classificação , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/fisiologia , Humanos , Insetos , Mamíferos , Mutagênese , Conformação Proteica , Septinas
17.
Artigo em Inglês | MEDLINE | ID: mdl-16511282

RESUMO

Septin 1 is a member of an evolutionarily conserved family of GTP-binding and filament-forming proteins named septins, which function in diverse processes including cytokinasis, vesicle trafficking, apoptosis, remodelling of the cytoskeleton, infection, neurodegeneration and neoplasia. Human septin 1 has been expressed and purified, but suffers from severe aggregation. Studies have shown that septin 1 with site-directed mutations of five serine residues (Ser19, Ser206, Ser307, Ser312 and Ser315) has a much lower degree of aggregation and better structural homogeneity and that the mutations cause only slight perturbations in the secondary structure of septin 1. This septin 1 mutant was crystallized and diffraction data were collected to 2.5 A resolution. The space group is P422, with unit-cell parameters a = b = 106.028, c = 137.852 A.


Assuntos
Mutagênese Sítio-Dirigida , Monoéster Fosfórico Hidrolases/química , Monoéster Fosfórico Hidrolases/genética , Cristalização , Cristalografia por Raios X , Humanos , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Serina/genética
18.
DNA Seq ; 16(4): 295-9, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16147889

RESUMO

Human THROMBOSPONDIN-1 play versatile roles in platelet aggregation, angiogenesis, and tumorigenesis, which forms a disulfide-linked homotrimeric complex. Here we reported that the genomic lotus of TSP1 also transcribes a natural antisense transcript (NAT) with an overlapping and reverse complement region against TSP1. The NAT of TSP1 was expressed in human testis, lung, thymus, colon, placenta, kidney and skeleton muscle, revealed by PCR amplification. It was also expressed in some tumor cell lines. The identification of NAT of TSP1 would be of significant importance to understand the functions of TSP1, and it would also suggest the potential attempt of using RNA interference for related tumor therapy, for instance, breast cancer.


Assuntos
DNA Antissenso/genética , Especificidade da Espécie , Trombospondina 1/genética , Sequência de Bases , Linhagem Celular Tumoral , DNA Antissenso/metabolismo , Expressão Gênica , Humanos , Dados de Sequência Molecular , Trombospondina 1/metabolismo , Distribuição Tecidual
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