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1.
Mol Cell Probes ; 49: 101473, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31654732

RESUMO

Respiratory syncytial virus (RSV) is a major causative agent of respiratory tract infection necessitating hospitalization in children. A rapid diagnostic method would facilitate early detection of RSV infection and timely implementation of special treatment. Here, a reverse transcription recombinase polymerase amplification (RT-RPA) assay combined with lateral flow dipstick (LFD) was evaluated for rapid visual detection of RSV. The primers were designed to target the conserved L gene. The RT-RPA-LFD assay could simultaneously detect RSV subtype A and B with the same detection limit of 10 copies of a given RNA molecule. Moreover, the assay showed no cross-reactivity with other common human pathogens. The performance of the RT-RPA-LFD assay was evaluated by testing 136 nasopharyngeal aspirates (NPAs). The agreement of the detection results between RT-RPA-LFD and qRT-PCR was 100% (34 positive and 102 negative cases). In summary, the developed RT-RPA-LFD assay had good performance in detecting RSV in clinical specimens, thus providing a novel alternative solution for the detection of RSV under field conditions.


Assuntos
Reação em Cadeia da Polimerase em Tempo Real/métodos , Recombinases/metabolismo , Vírus Sincicial Respiratório Humano/isolamento & purificação , Reologia/métodos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
2.
Hum Mol Genet ; 24(18): 5198-210, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26123488

RESUMO

Accumulation of amyloid-ß (Aß) in synaptic mitochondria is associated with mitochondrial and synaptic injury. The underlying mechanisms and strategies to eliminate Aß and rescue mitochondrial and synaptic defects remain elusive. Presequence protease (PreP), a mitochondrial peptidasome, is a novel mitochondrial Aß degrading enzyme. Here, we demonstrate for the first time that increased expression of active human PreP in cortical neurons attenuates Alzheimer disease's (AD)-like mitochondrial amyloid pathology and synaptic mitochondrial dysfunction, and suppresses mitochondrial oxidative stress. Notably, PreP-overexpressed AD mice show significant reduction in the production of proinflammatory mediators. Accordingly, increased neuronal PreP expression improves learning and memory and synaptic function in vivo AD mice, and alleviates Aß-mediated reduction of long-term potentiation (LTP). Our results provide in vivo evidence that PreP may play an important role in maintaining mitochondrial integrity and function by clearance and degradation of mitochondrial Aß along with the improvement in synaptic and behavioral function in AD mouse model. Thus, enhancing PreP activity/expression may be a new therapeutic avenue for treatment of AD.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Mitocôndrias/metabolismo , Neurônios/metabolismo , Agregação Patológica de Proteínas/metabolismo , Serina Endopeptidases/metabolismo , Sinapses/metabolismo , Doença de Alzheimer/fisiopatologia , Animais , Comportamento Animal , Células Cultivadas , Cognição , Modelos Animais de Doenças , Expressão Gênica , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Transgênicos , Estresse Oxidativo , Proteólise , Serina Endopeptidases/genética
3.
J Cell Biochem ; 115(6): 1159-65, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24415199

RESUMO

The antioxidant property of dimethyl sulfoxide (DMSO) was formerly attributed to its direct effects. Our former study showed that DMSO is able to induce heme oxygenase-1 (HO-1) expression in endothelial cells, which is a potent antioxidant enzyme. In this study, we hypothesized that the antioxidant effects of DMSO in cardiomyocytes are mediated or partially mediated by increased HO-1 expression. Therefore, we investigated whether DMSO exerts protective effects against H2 O2 -induced oxidative damage in cardiomyocytes, and whether HO-1 is involved in DMSO-imparted protective effects, and we also explore the underlying mechanism of DMSO-induced HO-1 expression. Our study demonstrated that DMSO pretreatment showed a cytoprotective effect against H2 O2 -induced oxidative damage (impaired cell viability, increased apopototic cells rate and caspase-3 level, and increased release of LDH and CK) and this process is partially mediated by HO-1 upregulation. Furthermore, our data showed that the activation of p38 MAPK and Nrf2 translocation are involved in the HO-1 upregulation induced by DMSO. This study reports for the first time that the cytoprotective effect of DMSO in cardiomyocytes is partially mediated by HO-1, which may further explain the mechanisms by which DMSO exerts cardioprotection on H2 O2 injury. J. Cell. Biochem. 115: 1159-1165, 2014. © 2013 Wiley Periodicals, Inc.


Assuntos
Dimetil Sulfóxido/farmacologia , Heme Oxigenase-1/metabolismo , Peróxido de Hidrogênio/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Caspase 3/metabolismo , Linhagem Celular , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Crioprotetores/farmacologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Oxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Regulação para Cima/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
4.
Gynecol Endocrinol ; 29(8): 775-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23767829

RESUMO

OBJECTIVE: To investigate the reproductive endocrine changes after inhba overexpression into rat ovary. METHOD: Thirty Sprague-Dawley rats were randomly assigned to three groups. Inhba overexpression lentivirus vectors (LV-eGFP-inhba) were microinjected into rat ovary (INH group); Control animals received the same amount lentivirus vector empty (CON group) or LV-eGFP (GFP group). Antral follicle amount and diameter were counted and serum level of activin A, E2, P, FSH, and LH and the expression of ER-α, ER-ß, PR, FSHR, and LHR were measured. RESULTS: There was no significant difference among three groups in antral follicle amount; antral follicle diameter was increased in INH group rats compared with the other group rats. Serum levels of activin A, E2, P, and FSH were increased and LH was decreased in INH group rats compared with the other group rats. The mRNA and protein expression of ER-α, ER-ß, FSHR was higher in INH group rats than that in the other group rats. There was no significant difference in mRNA and protein expression of PR among the three group rats, LHR expression was decreased in INH group rats compared with the other two group rats. CONCLUSION: inhba overexpression in rat ovary in vivo may change reproductive endocrine function.


Assuntos
Subunidades beta de Inibinas/genética , Folículo Ovariano/fisiologia , Reprodução/fisiologia , Animais , Feminino , Expressão Gênica , Técnicas de Transferência de Genes , Vetores Genéticos , Lentivirus , Microinjeções , Folículo Ovariano/anatomia & histologia , Ovário , Ratos , Ratos Sprague-Dawley , Ratos Transgênicos
5.
Biochim Biophys Acta ; 1782(11): 658-63, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18929647

RESUMO

In this study, we investigated the effects of ischemia/reperfusion and chemical hypoxia on the morphology, cell viability and expression of bystin and glial fibrillary acidic protein (GFAP) in primary cultured astrocytes which were prepared by the subculture method. The astrocytes in Hank's medium without glucose and serum (oxygen-glucose deprivation, ischemic cells) were first exposed to 1% O2 and then to 21% O2 (normoxia), or treated with different concentrations of CoCl2 or NaN3 for different periods. Relevant observations and measurements were then conducted. The findings showed that treatment with 1% O2 for 0.5 or 3 h could induce a characteristic 'reactive' morphology and a significant increase in cell viability and total protein amount. The western blot analysis showed that treatment with 1% O2 for 0.5 or 3 h also induced a significant increase in the expression of bystin and that the response of bystin to mild ischemia was much more sensitive than that of GFAP. Similar results were also found in the cells treated with mild chemical hypoxia. The data demonstrated for the first time that mild ischemia and hypoxia could activate astrocytes and that bystin is a much more sensitive marker in activated astrocytes induced by ischemia and hypoxia as compared to GFAP. The significant up-regulation of bystin suggests that bystin may play an important role in the activation of astrocytes as well as in the neuroprotective role of hypoxic and ischemic preconditioning.


Assuntos
Astrócitos/metabolismo , Isquemia Encefálica/metabolismo , Moléculas de Adesão Celular/metabolismo , Hipóxia , Reperfusão , Animais , Animais Recém-Nascidos , Antimutagênicos/farmacologia , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Forma Celular , Sobrevivência Celular , Células Cultivadas , Cobalto/farmacologia , Proteína Glial Fibrilar Ácida/metabolismo , Hipóxia/induzido quimicamente , Hipóxia/metabolismo , Camundongos
6.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 30(2): 222-225, 2018 Mar 01.
Artigo em Zh | MEDLINE | ID: mdl-29770672

RESUMO

OBJECTIVE: To evaluate the effect of cementing ditch-based project on schistosomiasis control in the irrigation area of Dingshen River basin in Shitai County, Anhui Province. METHODS: The data of Oncomelania hupensis snail surveys from 2009 to 2015 and the data of schistosome infections in humans and livestock from 2009 to 2015 were collected, and the changes of the epidemic situation were analyzed and compared before and after the project. RESULTS: In the cementing ditches, the occurrence rate of living snails decreased by 68.79% and the average density of living snails decreased by 97.78%, whereas in the control areas without ditch hardening, the occurrence rate of living snails increased by 72.49% and the average density of living snails increased by 37.16%. The infection rate in humans decreased by 100%. Of 161 bovines examined with the egg-hatching method during the period, no infections were found. CONCLUSIONS: The cementing ditch-based project has a good effect on reducing the density of snails and controlling schistosomiasis.


Assuntos
Engenharia Sanitária , Esquistossomose/prevenção & controle , Caramujos , Animais , Bovinos/parasitologia , China , Reservatórios de Doenças/parasitologia , Humanos , Gado , Rios , Schistosoma
7.
Stem Cell Reports ; 7(4): 678-692, 2016 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-27666790

RESUMO

Mitochondria are critical to neurogenesis, but the mechanisms of mitochondria in neurogenesis have not been well explored. We fully characterized mitochondrial alterations and function in relation to the development of human induced pluripotent stem cell (hiPSC)-derived dopaminergic (DA) neurons. Following directed differentiation of hiPSCs to DA neurons, mitochondria in these neurons exhibit pronounced changes during differentiation, including mature neurophysiology characterization and functional synaptic network formation. Inhibition of mitochondrial respiratory chains via application of complex IV inhibitor KCN (potassium cyanide) or complex I inhibitor rotenone restricted neurogenesis of DA neurons. These results demonstrated the direct importance of mitochondrial development and bioenergetics in DA neuronal differentiation. Our study also provides a neurophysiologic model of mitochondrial involvement in neurogenesis, which will enhance our understanding of the role of mitochondrial dysfunctions in neurodegenerative diseases.


Assuntos
Diferenciação Celular , Neurônios Dopaminérgicos/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Mesencéfalo/citologia , Mesencéfalo/metabolismo , Mitocôndrias/metabolismo , Biomarcadores , Movimento Celular , Neurônios Dopaminérgicos/citologia , Fenômenos Eletrofisiológicos , Humanos , Fenótipo , Sinapses/metabolismo
8.
Sci Rep ; 6: 31462, 2016 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-27535796

RESUMO

Mitochondria are essential dynamic organelles for energy production. Mitochondria dynamically change their shapes tightly coupled to fission and fusion. Imbalance of fission and fusion can cause deficits in mitochondrial respiration, morphology and motility. Mfn2 (mitofusin 2), a mitochondrial membrane protein that participates in mitochondrial fusion in mammalian cells, contributes to the maintenance and operation of the mitochondrial network. Due to lack of applicable model systems, the mechanisms and involvement of mitochondria in neurogenesis in human brain cells have not been well explored. Here, by employing the human induced pluripotent stem cells (hiPSCs) differentiation system, we fully characterized mitochondrial development, neurogenesis and synapse formation in hiPSCs-derived cortical neurons. Differentiation of hiPSCs to cortical neurons with extended period demonstrates mature neurophysiology characterization and functional synaptic network formation. Mitochondrial respiration, morphology and motility in the differentiated neurons also exhibit pronounced development during differentiation. Mfn2 knock-down results in deficits in mitochondrial metabolism and network, neurogenesis and synapse formation, while Mfn2 overexpression enhances mitochondrial bioenergetics and functions, and promotes the differentiation and maturation of neurons. Together, our data indicate that Mfn2 is essential for human mitochondrial development in neuronal maturation and differentiation, which will enhance our understanding of the role of Mfn2 in neurogenesis.


Assuntos
GTP Fosfo-Hidrolases/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Neurônios/metabolismo , Sinapses/metabolismo , Trifosfato de Adenosina/metabolismo , Células da Medula Óssea/citologia , Diferenciação Celular , Células Cultivadas , GTP Fosfo-Hidrolases/antagonistas & inibidores , GTP Fosfo-Hidrolases/genética , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Potenciais da Membrana , Mitocôndrias/patologia , Proteínas Mitocondriais/antagonistas & inibidores , Proteínas Mitocondriais/genética , Neurogênese , Neurônios/citologia , Técnicas de Patch-Clamp , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Sinaptofisina/metabolismo , Tubulina (Proteína)/metabolismo
9.
J Alzheimers Dis ; 54(2): 679-90, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27567872

RESUMO

Mitochondrial dysfunction and axonal degeneration are early pathological features of Alzheimer's disease (AD)-affected brains. The underlying mechanisms and strategies to rescue it have not been well elucidated. Here, we evaluated axonal mitochondrial transport and function in AD subject-derived mitochondria. We analyzed mitochondrial transport and kinetics in human trans-mitochondrial "cybrid" (cytoplasmic hybrid) neuronal cells whose mitochondria were derived from platelets of patients with sporadic AD and compared these AD cybrid cell lines with cybrid cell lines whose mitochondria were derived from age-matched, cognitively normal subjects. Human AD cybrid cell lines, when induced to differentiate, developed stunted projections. Mitochondrial transport and function within neuronal processes/axons was altered in AD-derived mitochondria. Antioxidants reversed deficits in axonal mitochondrial transport and function. These findings suggest that antioxidants may be able to mitigate the consequences of AD-associated mitochondrial dysfunction. The present study provides evidence of the cause/effect of AD specific mitochondrial defects, which significantly enhances our understanding of the AD pathogenesis and exploring the effective therapeutic strategy for AD.


Assuntos
Doença de Alzheimer/metabolismo , Antioxidantes/metabolismo , Diferenciação Celular/fisiologia , Mitocôndrias/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Transporte Biológico/fisiologia , Linhagem Celular , DNA Mitocondrial/metabolismo , Feminino , Humanos , Masculino , Mitocôndrias/patologia
10.
ACS Med Chem Lett ; 7(3): 294-9, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26985318

RESUMO

Cyclophilin D (CypD), a peptidylprolyl isomerase F (PPIase), plays a central role in opening the mitochondrial membrane permeability transition pore leading to cell death. CypD resides in the mitochondrial matrix, associates with the inner mitochondrial membrane, interacts with amyloid beta to exacerbate mitochondrial and neuronal stress and has been linked to Alzheimer's disease (AD). We report the biological activity of a small-molecule CypD inhibitor (C-9), which binds strongly to CypD and attenuates mitochondrial and cellular perturbation insulted by Aß and calcium stress. Binding affinities for C-9 were determined using in vitro surface plasmon resonance. This compound antagonized calcium-mediated mitochondrial swelling, abolished Aß-induced mitochondrial dysfunction as shown by increased cytochrome c oxidase activity and adenosine-5'-triphosphate levels, and inhibited CypD PPIase enzymatic activity by real-time fluorescence capture assay using Hamamatsu FDSS 7000. Compound C-9 seems a good candidate for further investigation as an AD drug.

11.
J Alzheimers Dis ; 51(2): 571-80, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26890765

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized clinically by cognitive decline and memory loss. The pathological features are amyloid-ß peptide (Aß) plaques and intracellular neurofibrillary tangles. Many studies have suggested that oxidative damage induced by reactive oxygen species (ROS) is an important mechanism for AD progression. Our recent study demonstrated that oxidative stress could further impair mitochondrial function. In the present study, we adopted a transgenic mouse model of AD (mAPP, overexpressing AßPP/Aß in neurons) and performed redox measurements using in vivo electron paramagnetic resonance (EPR) imaging with methoxycarbamyl-proxyl (MCP) as a redox-sensitive probe for studying oxidative stress in an early stage of pathology in a transgenic AD mouse model. Through assessing oxidative stress, mitochondrial function and cognitive behaviors of mAPP mice at the age of 8-9 months, we found that oxidative stress and mitochondrial dysfunction appeared in the early onset of AD. Increased ROS levels were associated with defects of mitochondrial and cognitive dysfunction. Notably, the in vivo EPR method offers a unique way of assessing tissue oxidative stress in living animals under noninvasive conditions, and thus holds a potential for early diagnosis and monitoring the progression of AD.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Mitocôndrias/metabolismo , Estresse Oxidativo/fisiologia , Trifosfato de Adenosina/metabolismo , Idade de Início , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Encéfalo/diagnóstico por imagem , Cognição/fisiologia , Modelos Animais de Doenças , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Humanos , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos Transgênicos , Espécies Reativas de Oxigênio/metabolismo , Memória Espacial/fisiologia
12.
Eur J Hum Genet ; 13(7): 823-8, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15841095

RESUMO

Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) is important for downregulation of T-cell activation, and CTLA-4 gene polymorphisms have been implicated as risk factors for rheumatoid arthritis (RA). Previous studies of the association between the +49 polymorphism of the CTLA-4 gene in RA have provided conflicting results. In order to determine association of the CTLA-4 gene with RA in Chinese Han population, we used denaturing gradient gel electrophoresis (DGGE) to genotype polymorphisms of four SNPs (MH30, +49, CT60 and JO31) of the CTLA-4 gene in 326 RA patients and 250 healthy controls. Furthermore, meta-analysis of all available studies relating +49 polymorphism to the risk of RA was performed to confirm the disease association. Among the SNPs examined, the genotype frequencies of CTLA-4 +49 and CT60 in RA patients differed significantly from controls (P=0.028 and 0.007). In addition, the distribution of four haplotypes constructed by these two SNPs was significantly different between patients and controls (chi(2)=10.58, d.f. =3, P=0.014). The meta-analysis also revealed that in both European and Asian populations, the CLTA-4 +49 G allele was associated with the risk of RA. These results suggested that the CTLA-4 gene might be involved in the susceptibility to RA in the Chinese Han population and both +49 and CT60 of CTLA-4 gene might be the causal variants in RA disease.


Assuntos
Antígenos de Diferenciação/genética , Artrite Reumatoide/genética , Predisposição Genética para Doença , Polimorfismo Genético , Regiões 3' não Traduzidas , Adulto , Antígenos CD , Povo Asiático/genética , Antígeno CTLA-4 , Estudos de Casos e Controles , China , Feminino , Genética Populacional , Haplótipos/genética , Humanos , Masculino , Metanálise como Assunto , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
13.
J Alzheimers Dis ; 43(2): 451-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25096625

RESUMO

Diabetes is considered to be a risk factor in Alzheimer's disease (AD) pathogenesis. Although recent evidence indicates that diabetes exaggerates pathologic features of AD, the underlying mechanisms are not well understood. To determine whether mitochondrial perturbation is associated with the contribution of diabetes to AD progression, we characterized mouse models of streptozotocin (STZ)-induced type 1 diabetes and transgenic AD mouse models with diabetes. Brains from mice with STZ-induced diabetes revealed a significant increase of cyclophilin D (CypD) expression, reduced respiratory function, and decreased hippocampal long-term potentiation (LTP); these animals had impaired spatial learning and memory. Hyperglycemia exacerbated the upregulation of CypD, mitochondrial defects, synaptic injury, and cognitive dysfunction in the brains of transgenic AD mice overexpressing amyloid-ß as shown by decreased mitochondrial respiratory complex I and IV enzyme activity and greatly decreased mitochondrial respiratory rate. Concomitantly, hippocampal LTP reduction and spatial learning and memory decline, two early pathologic indicators of AD, were enhanced in the brains of diabetic AD mice. Our results suggest that the synergistic interaction between effects of diabetes and AD on mitochondria may be responsible for brain dysfunction that is in common in both diabetes and AD.


Assuntos
Doença de Alzheimer/complicações , Diabetes Mellitus Experimental/complicações , Deficiências da Aprendizagem/etiologia , Transtornos da Memória/etiologia , Mitocôndrias/patologia , Sinapses/patologia , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Modelos Animais de Doenças , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Potenciais Pós-Sinápticos Excitadores/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Hipocampo/patologia , Humanos , Técnicas In Vitro , Deficiências da Aprendizagem/patologia , Transtornos da Memória/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias/fisiologia , Mutação/genética , Consumo de Oxigênio/fisiologia , Aprendizagem Espacial/efeitos dos fármacos , Aprendizagem Espacial/fisiologia , Fatores de Tempo
14.
Diabetes ; 64(5): 1728-42, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25412623

RESUMO

Diabetes has adverse effects on the brain, especially the hippocampus, which is particularly susceptible to synaptic injury and cognitive dysfunction. The underlying mechanisms and strategies to rescue such injury and dysfunction are not well understood. Using a mouse model of type 2 diabetes (db/db mice) and a human neuronal cell line treated with high concentration of glucose, we demonstrate aberrant mitochondrial morphology, reduced ATP production, and impaired activity of complex I. These mitochondrial abnormalities are induced by imbalanced mitochondrial fusion and fission via a glycogen synthase kinase 3ß (GSK3ß)/dynamin-related protein-1 (Drp1)-dependent mechanism. Modulation of the Drp1 pathway or inhibition of GSK3ß activity restores hippocampal long-term potentiation that is impaired in db/db mice. Our results point to a novel role for mitochondria in diabetes-induced synaptic impairment. Exploration of the mechanisms behind diabetes-induced synaptic deficit may provide a novel treatment for mitochondrial and synaptic injury in patients with diabetes.


Assuntos
Dinaminas/metabolismo , Mitocôndrias/patologia , Plasticidade Neuronal/fisiologia , Animais , Linhagem Celular , Dinaminas/genética , Regulação da Expressão Gênica , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Camundongos , Camundongos Endogâmicos NOD , Mitocôndrias/metabolismo , Neurônios/metabolismo
15.
J Phys Chem B ; 119(17): 5716-27, 2015 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-25839972

RESUMO

Although a shear flow field and ß-nucleating agents (ß-NAs) can separately induce the formation of ß-crystals in isotactic polypropylene (iPP) in an efficient manner, we previously encountered difficulty in obtaining abundant ß-crystals when these two factors were applied due to the competitive growth of α- and ß-crystals. In the current study, to induce the formation of a high fraction of ß-crystals, a strategy that introduces a relaxation process after applying a shear flow field but before cooling to crystallize ß-nucleated iPP was proposed. Depending on the relaxation state of the shear-induced oriented precursors, abundant ß-crystals with a refined orientation morphology were indeed formed. The key to producing these crystals lay in the partially dissolved shear-induced oriented precursors as a result of the relaxation process's ability to generate ß-crystals by inducing the formation of needlelike ß-NAs. Therefore, the content of ß-crystals gradually increased with relaxation time, whereas the overall crystallization kinetics progressively decreased. Moreover, more time was required for the content of the ß-phase to increase to the (maximum) value observed in quiescent crystallization than for the effect of flow on crystallization kinetics to be completely eliminated. The c-axis of the oriented ß-lamellae was observed to be perpendicular, rather than parallel, to the fiber axis of the needlelike ß-NAs, as first evidenced by the unique small-angle X-ray scattering patterns obtained. The significance of the relaxation process was manifested in regulating the content and morphology of oriented ß-crystals in sheared, ß-nucleated iPP and thus in the structure and property manipulation of iPP.

16.
J Alzheimers Dis ; 42(1): 333-44, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24858403

RESUMO

A major obstacle to the development of effective treatment of Alzheimer's disease (AD) is successfully delivery of drugs to the brain. We have previously identified a series of benzothiazole phosphonate compounds that block the interaction of amyloid-ß peptide with amyloid-ß binding alcohol dehydrogenase (ABAD). A selective and sensitive method for the presence of three new benzothiazole ABAD inhibitors in mouse plasma, brain, and artificial cerebrospinal fluid has been developed and validated based on high performance liquid chromatography tandem mass spectrometry. Mass spectra were generated using Micromass Quattro Ultima "triple" quadrupole mass spectrometer equipped with an Electrospray Ionization interface. Good linearity was obtained over a concentration range of 0.05-2.5 µg/ml. The lowest limit of quantification and detection was found to be 0.05 µg/ml. All inter-day accuracies and precisions were within ± 15% of the nominal value and ± 20%, respectively, at the lower limit of quantitation. The tested compounds were stable at various conditions with recoveries >90.0% (RSD <10%). The method used for pharmacokinetic studies of compounds in mouse cerebrospinal fluid, plasma, and brain is accurate, precise, and specific with no matrix effect. Pharmacokinetic data showed that these compounds penetrate the blood-brain barrier (BBB) yielding 4-50 ng/ml peak brain concentrations and 2 µg/ml peak plasma concentrations from a 10 mg/kg dose. These results indicate that our newly synthesized small molecule ABAD inhibitors have a good drug properties with the ability to cross the blood-brain barrier, which holds a great potential for AD therapy.


Assuntos
3-Hidroxiacil-CoA Desidrogenases/antagonistas & inibidores , Barreira Hematoencefálica/metabolismo , Inibidores Enzimáticos/farmacocinética , Doença de Alzheimer/tratamento farmacológico , Animais , Encéfalo/metabolismo , Calibragem , Cromatografia Líquida de Alta Pressão , Camundongos , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
17.
Neurochem Int ; 55(4): 181-6, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19121359

RESUMO

The neuroprotective roles of both hypothermia and ginkgolides have been well confirmed. We first examined whether hypothermia (32 or 28 degrees C) or ginkgolides have a protective effect on astrocytes against ischemia and reperfusion-induced injury. We demonstrated that ginkgolides, but not hypothermia, have a significantly time- and concentration-dependent protective role in ischemic astrocytes. We then investigated whether co-treatment with hypothermia and ginkgolides has a synergistic role to protect astrocytes against ischemia and reperfusion-induced injury. Cells were incubated with 18.75, 37.5 or 75 microg/ml of ginkgolides at 37, 32 or 28 degrees C for 24, 48 or 72 h before exposure to ischemia (24h) and then reperfusion (24h). Data showed that the co-treatment induced a significant decrease, rather than an increase as we had expected, in their cellular viabilities and anti-apoptotic abilities as compared with the cells treated by ginkgolides only. Western blot analysis demonstrated that hypothermia (32 or 28 degrees C for 24h) has no effect on the expression of Hypoxia-inducible factor-1 alpha (HIF-1 alpha) protein, suggesting that HIF-1 alpha is not associated with the adverse effect of hypothermia on ginkgolides. The findings imply the importance of further investigating the effects of hypothermia on the pharmacological role or therapeutic efficacy of drugs commonly used clinically.


Assuntos
Astrócitos/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Ginkgolídeos/uso terapêutico , Hipotermia Induzida/efeitos adversos , Fármacos Neuroprotetores/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Astrócitos/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/fisiopatologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Ginkgolídeos/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/fisiopatologia , Fatores de Tempo
18.
J Cell Mol Med ; 12(2): 569-79, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18419598

RESUMO

Transferrin and transferrin receptor are two key proteins of iron metabolism that have been identified to be hypoxia-inducible genes. Divalent metal transporter 1 (DMT1) is also a key transporter of iron under physiological conditions. In addition, in the 5' regulatory region of human DMT1 (between -412 and -570), there are two motifs (CCAAAGTGCTGGG) that are similar to hypoxia-inducible factor-1 (HIF-1) binding sites. It was therefore speculated that DMT1 might also be a hypoxia-inducible gene. We investigated the effects of hypoxia and hypoxia/re-oxygenation on the expression of DMT1 and the content of HIF-1alpha in HepG2 cells. As we expected, a very similar tendency in the responses of the expression of HIF-1alpha, DMT1+IRE (iron response element) and DMT1-IRE proteins to chemical (CoCl(2)) or physical hypoxia was observed. A highly significant correlation was found between the expression of DMT1 proteins and the contents of HIF-1 in hypoxic cells. After the cells were exposed to hypoxia and subsequent normoxia, no HIF-1alpha could be detected and a significant decrease in DMT1+IRE expression (P<0.05), but not in DMT1-IRE protein (versus the hypoxia group), was observed. The findings implied that the HIF-1 pathway might have a role in the regulation of DMT1+IRE expression during hypoxia.


Assuntos
Carcinoma Hepatocelular/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Fator 1 Induzível por Hipóxia/metabolismo , Proteínas Reguladoras de Ferro/metabolismo , Neoplasias Hepáticas/metabolismo , Carcinoma Hepatocelular/patologia , Proteínas de Transporte de Cátions/genética , Hipóxia Celular , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Cobalto/farmacologia , Citoplasma/metabolismo , Relação Dose-Resposta a Droga , Humanos , Fator 1 Induzível por Hipóxia/genética , Imuno-Histoquímica , Proteínas Reguladoras de Ferro/genética , Neoplasias Hepáticas/patologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Fatores de Tempo
19.
J Neurosci Res ; 78(5): 723-31, 2004 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-15478178

RESUMO

Microglial activation is believed to play a pivotal role in the selective neuronal injury associated with several neurodegenerative disorders, including Parkinson's disease (PD) and Alzheimer's disease. We provide evidence that (-)-epigallocatechin gallate (EGCG), a major monomer of green tea polyphenols, potently inhibits lipopolysaccharide (LPS)-activated microglial secretion of nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) through the down-regulation of inducible NO synthase and TNF-alpha expression. In addition, EGCG exerted significant protection against microglial activation-induced neuronal injury both in the human dopaminergic cell line SH-SY5Y and in primary rat mesencephalic cultures. Our study demonstrates that EGCG is a potent inhibitor of microglial activation and thus is a useful candidate for a therapeutic approach to alleviating microglia-mediated dopaminergic neuronal injury in PD.


Assuntos
Antioxidantes/farmacologia , Catequina/análogos & derivados , Catequina/farmacologia , Dopamina/metabolismo , Microglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Análise de Variância , Animais , Animais Recém-Nascidos , Antioxidantes/uso terapêutico , Western Blotting/métodos , Carbocianinas , Catequina/uso terapêutico , Contagem de Células/métodos , Células Cultivadas , Meios de Cultivo Condicionados/metabolismo , Meios de Cultivo Condicionados/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Lipopolissacarídeos/farmacologia , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Neuroblastoma , Óxido Nítrico/metabolismo , RNA Mensageiro/biossíntese , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sais de Tetrazólio , Tiazóis , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
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