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1.
BMC Neurol ; 16: 66, 2016 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-27176725

RESUMO

BACKGROUND: Our previous randomized double-blind study showed that drinking hydrogen (H2) water for 48 weeks significantly improved the total Unified Parkinson's Disease Rating Scale (UPDRS) score of Parkinson's disease (PD) patients treated with levodopa. We aim to confirm this result using a randomized double-blind placebo-controlled multi-center trial. METHODS: Changes in the total UPDRS scores from baseline to the 8(th), 24(th), 48(th), and 72(nd) weeks, and after the 8(th) week, will be evaluated. The primary endpoint of the efficacy of this treatment in PD is the change in the total UPDRS score from baseline to the 72(nd) week. The changes in UPDRS part II, UPDRS part III, each UPDRS score, PD Questionnaire-39 (PDQ-39), and the modified Hoehn and Yahr stage at these same time-points, as well as the duration until the protocol is finished because additional levodopa is required or until the disease progresses, will also be analyzed. Adverse events and screening laboratory studies will also be examined. Participants in the hydrogen water group will drink 1000 mL/day of H2 water, and those in the placebo water group will drink normal water. One-hundred-and-seventy-eight participants with PD (88 women, 90 men; mean age: 64.2 [SD 9.2] years, total UPDRS: 23.7 [11.8], with levodopa medication: 154 participants, without levodopa medication: 24 participants; daily levodopa dose: 344.1 [202.8] mg, total levodopa equivalent dose: 592.0 [317.6] mg) were enrolled in 14 hospitals and were randomized. DISCUSSION: This study will confirm whether H2 water can improve PD symptoms. TRIAL REGISTRATION: UMIN000010014 (February, 13, 2013).


Assuntos
Hidrogênio/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Água , Idoso , Antiparkinsonianos/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Levodopa/uso terapêutico , Masculino , Pessoa de Meia-Idade
2.
Gan To Kagaku Ryoho ; 41 Suppl 1: 30-2, 2014 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-25595075

RESUMO

Drug adherence is central to the treatment of dementia, which might reduce compliance due to memory loss, particularly among home-based patients with dementia. In order to improve drug adherence, we suggest the efficient and effective supervised administration by use of information communication technology(ICT). ICT makes face-to-face real-time communication possible, and it also enables picture sharing. Therefore, it might be useful to apply ICT to controlling and supervising medication for patients with dementia to improve drug adherence. Accordingly, we enrolled patients who were supposed to take a newly prescribed anti-dementia patch containing the choline esterase inhibitor rivastigmine(Rivastach®)and investigated the effect of ICT-based intervention for drug adherence, emotional change, and cognitive change, utilizing Skype, a free communication software program. Scheduled Skype interventions increased drug adherence ratio, levels of subjective satisfaction, and instrumental activities of daily living(IADL). Furthermore, we can provide patients and their caregivers with a feeling of safety through regular bidirectional communication, as patients can easily consult medical staff regarding the adverse effects of newly prescribed drugs. Instead of frequent visits to their primary physicians, ICT-based communications can be used as a substitute for supervision of medication, given the availability of the telecommunication system. By directly connecting the medical institution to the home, we expect that this ICT-based system will expand into the geriatric care field, including the care of elderly individuals living alone.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Telemedicina , Idoso , Idoso de 80 Anos ou mais , Cuidadores , Cognição , Feminino , Serviços de Assistência Domiciliar , Humanos , Masculino , Pessoa de Meia-Idade
3.
J Biol Chem ; 287(27): 23024-33, 2012 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-22563077

RESUMO

Accumulating evidence suggests that some dietary patterns, specifically high fat diet (HFD), increase the risk of developing sporadic Alzheimer disease (AD). Thus, interventions targeting HFD-induced metabolic dysfunctions may be effective in preventing the development of AD. We previously demonstrated that amyloid precursor protein (APP)-overexpressing transgenic mice fed HFD showed worsening of cognitive function when compared with control APP mice on normal diet. Moreover, we reported that voluntary exercise ameliorates HFD-induced memory impairment and ß-amyloid (Aß) deposition. In the present study, we conducted diet control to ameliorate the metabolic abnormality caused by HFD on APP transgenic mice and compared the effect of diet control on cognitive function with that of voluntary exercise as well as that of combined (diet control plus exercise) treatment. Surprisingly, we found that exercise was more effective than diet control, although both exercise and diet control ameliorated HFD-induced memory deficit and Aß deposition. The production of Aß was not different between the exercise- and the diet control-treated mice. On the other hand, exercise specifically strengthened the activity of neprilysin, the Aß-degrading enzyme, the level of which was significantly correlated with that of deposited Aß in our mice. Notably, the effect of the combination treatment (exercise and diet control) on memory and amyloid pathology was not significantly different from that of exercise alone. These studies provide solid evidence that exercise is a useful intervention to rescue HFD-induced aggravation of cognitive decline in transgenic model mice of AD.


Assuntos
Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/genética , Gorduras na Dieta/farmacologia , Transtornos da Memória/prevenção & controle , Condicionamento Físico Animal/fisiologia , Doença de Alzheimer/dietoterapia , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Ração Animal , Animais , Cognição/fisiologia , Modelos Animais de Doenças , Feminino , Humanos , Hipercolesterolemia/dietoterapia , Hipercolesterolemia/genética , Hiperinsulinismo/dietoterapia , Hiperinsulinismo/genética , Masculino , Transtornos da Memória/dietoterapia , Transtornos da Memória/genética , Doenças Metabólicas/dietoterapia , Doenças Metabólicas/genética , Camundongos , Camundongos Transgênicos , Neprilisina/metabolismo , Obesidade/dietoterapia , Obesidade/genética
5.
J Biol Chem ; 286(28): 25309-16, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21622565

RESUMO

Presenilin (PS), a causative molecule of familial Alzheimer disease, acts as a crucial component of the γ-secretase complex, which is required to cleave type I transmembrane proteins such as amyloid precursor protein and Notch. However, it also functions through γ-secretase-independent pathways. Recent reports suggested that PS could regulate the expression level of cell surface receptors, including the PDGF and EGF receptors, followed by modulating their downstream pathways via γ-secretase-independent mechanisms. The main purpose of this study was to clarify the effect of PS on expression of the insulin receptor (IR) as well as on insulin signaling. Here, we demonstrate that PS inhibited IR transcription and reduced IR expression, and this was followed by down-regulation of insulin signaling. Moreover, we suggest that neither γ-secretase activity nor Wnt/ß-catenin signaling can reduce the expression of IR, but a PS-mediated increase in the intracellular Ca(2+) level can be associated with it. These results clearly indicate that PS can functionally regulate insulin signaling by controlling IR expression.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Sinalização do Cálcio/fisiologia , Regulação da Expressão Gênica/fisiologia , Insulina/metabolismo , Presenilinas/metabolismo , Receptor de Insulina/biossíntese , Secretases da Proteína Precursora do Amiloide/genética , Animais , Cálcio/metabolismo , Células Cultivadas , Insulina/genética , Camundongos , Camundongos Knockout , Presenilinas/genética , Receptor de Insulina/genética , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/fisiologia , beta Catenina/genética , beta Catenina/metabolismo
6.
J Neurochem ; 121(6): 964-73, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22443192

RESUMO

We have recently reported that Presenilin 1 (PS1), a causative gene of familial Alzheimer disease (AD), down-regulates the expression level of insulin receptor (IR) as well as its signaling through a γ-secretase-independent pathway. PS1 is phosphorylated by glycogen synthase kinase 3 ß at the serine 353 and 357 residues. The main purpose of the present study was to clarify the effect of PS1 phosphorylation on IR/insulin signaling. Here, we demonstrate that the pseudo-phosphorylation mutant of PS1 inhibited IR transcription and reduced IR expression compared with wild-type PS1. Importantly, there was a decrease in expression of IR in AD brains, and the phosphorylation ratio of PS1 was negatively correlated with IR level in human brain samples. In the data from mouse models of AD, IR reduction was not observed at the pre-Aß deposition stage but became apparent in that of post-Aß deposition. Together with our previous reports, these results suggest that phosphorylated PS1 can promote the down-regulation of insulin signaling, which may be a positive feed-forward mechanism inhibiting insulin signaling. As insulin resistance is reported to be a risk factor for sporadic AD, this PS1-mediated regulatory mechanism of brain insulin signaling may be causally associated with AD pathology.


Assuntos
Doença de Alzheimer/metabolismo , Insulina/metabolismo , Presenilina-1/metabolismo , Receptor de Insulina/metabolismo , Transdução de Sinais/fisiologia , Idoso , Idoso de 80 Anos ou mais , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Fosforilação
7.
Biochem Biophys Res Commun ; 426(1): 94-9, 2012 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-22922102

RESUMO

Rotenone, a mitochondrial complex I inhibitor, has been used to generate animal and cell culture models of Parkinson's disease. Recent studies suggest that microtubule destabilization causes selective dopaminergic neuronal loss. In this study, we investigated glycogen synthase kinase-3ß (GSK3ß) involvement in rotenone-induced microtubule destabilization. Rotenone-induced cytotoxicity in SH-SY5Y cells was attenuated by the GSK3ß inhibitor SB216763. Tau, a microtubule-associated protein and substrate for GSK3ß, has been implicated in the pathogenesis of tauopathies such as Alzheimer's disease. Rotenone induced an increase in phosphorylated tau, the effect of which was attenuated by concomitant treatment with SB216763. Rotenone treatment also decreased tau expression in the microtubule fraction and increased tau expression in the cytosol fraction. These effects were suppressed by SB216763, which suggests that rotenone reduces the capacity of tau to bind microtubules. Rotenone treatment increased the amount of free tubulin and reduced the amount of polymerized tubulin, indicating that rotenone destabilizes microtubules. Rotenone-induced microtubule destabilization was suppressed by SB216763 and taxol, a microtubule stabilizer. Taxol prevented rotenone-induced cytotoxicity and morphological changes. Taken together, these results suggest that rotenone-induced cytotoxicity is mediated by microtubule destabilization via GSK3ß activation, and that microtubule destabilization is caused by reduction in the binding capacity of tau to microtubules, which is a result of tau phosphorylation via GSK3ß activation.


Assuntos
Complexo I de Transporte de Elétrons/antagonistas & inibidores , Quinase 3 da Glicogênio Sintase/metabolismo , Microtúbulos/efeitos dos fármacos , Rotenona/farmacologia , Moduladores de Tubulina/farmacologia , Linhagem Celular Tumoral , Quinase 3 da Glicogênio Sintase/genética , Glicogênio Sintase Quinase 3 beta , Humanos , Indóis/farmacologia , Maleimidas/farmacologia , Microtúbulos/metabolismo , Paclitaxel/farmacologia , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/metabolismo , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Proteínas tau/metabolismo
9.
Urol Int ; 89(2): 162-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22868217

RESUMO

Bicalutamide is an anti-androgen that is used worldwide to treat prostate cancer (CaP). However, there are no data on blood bicalutamide concentrations in hemodialysis (HD) patients with CaP. Therefore, we investigated the plasma levels of bicalutamide during the peridialysis period in this population. The study group included 5 HD patients with CaP who had been treated with bicalutamide (80 mg/day) for at least 3 months. Blood samples were taken during and between HD sessions and the plasma concentrations of the active R enantiomer (R-bicalutamide) were assessed using an HPLC assay. The plasma R-bicalutamide levels on the non-dialysis day were measured in 2 patients (patients 1 and 2) immediately before dosing and 8 and 24 h after dosing. These levels were 18,730, 19,090 and 19,420 ng/ml (patient 1), and 4,522, 4,581, and 5,296 ng/ml (patient 2), respectively. The mean plasma levels of R-bicalutamide in all 5 subjects just before HD, and 2 and 4 h after the start of HD were 8,726, 9,354 and 10,068 ng/ml, respectively. These results show that bicalutamide does not accumulate and is not diluted in the blood circulation of HD patients when given at the normal dosage used in the general population.


Assuntos
Anilidas/sangue , Falência Hepática/complicações , Falência Hepática/tratamento farmacológico , Nitrilas/sangue , Neoplasias da Próstata/complicações , Neoplasias da Próstata/tratamento farmacológico , Diálise Renal/métodos , Compostos de Tosil/sangue , Idoso , Anilidas/farmacocinética , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Nitrilas/farmacocinética , Estereoisomerismo , Fatores de Tempo , Compostos de Tosil/farmacocinética
10.
Gan To Kagaku Ryoho ; 39 Suppl 1: 45-7, 2012 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-23268897

RESUMO

In our laboratory, we draw up research aims to improve medication compliance in patients with dementia by video phone, and we have intervened in the cases of 3 patients to date. In this study, we focused on patients who are using a rivastigmine patch for Alzheimer' disease, which can be confirmed by video phone, to examine its efficacy. Specifically, by monitoring the effects of the treatment, skin side effects, of skin and usability for patients and caregivers, we monitor the dosing schedule to prevent interruption of self-medication, with the aim of improving compliance and treatment efficacy. We also consider methods of intervention for increasing the persistence rate of the rivastigmine patch and quality of life(QOL)by using the effectiveness of the video phone to focus on the symptoms of skin side effects. In addition, we examine the interventions that reduce the care burden and anxiety of caregivers by listening during the regular intervention.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Monitoramento de Medicamentos/instrumentação , Internet , Humanos
11.
J Neurochem ; 119(2): 354-63, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21699541

RESUMO

Sequential processing of amyloid precursor protein (APP) by ß- and γ-secretase leads to the generation of amyloid-ß (Aß) peptides, which plays a central role in Alzheimer's disease pathogenesis. APP is capable of forming a homodimer through its extracellular domain as well as transmembrane GXXXG motifs. A number of reports have shown that dimerization of APP modulates Aß production. On the other hand, we have previously reported that N-cadherin-based synaptic contact is tightly linked to Aß production. In the present report, we investigated the effect of N-cadherin expression on APP dimerization and metabolism. Here, we demonstrate that N-cadherin expression facilitates cis-dimerization of APP. Moreover, N-cadherin expression led to increased production of Aß as well as soluble APPß, indicating that ß-secretase-mediated cleavage of APP is enhanced. Interestingly, N-cadherin expression affected neither dimerization of C99 nor Aß production from C99, suggesting that the effect of N-cadherin on APP metabolism is mediated through APP extracellular domain. We confirmed that N-cadherin enhances APP dimerization by a novel luciferase-complementation assay, which could be a platform for drug screening on a high-throughput basis. Taken together, our results suggest that modulation of APP dimerization state could be one of mechanisms, which links synaptic contact and Aß production.


Assuntos
Peptídeos beta-Amiloides/biossíntese , Precursor de Proteína beta-Amiloide/metabolismo , Caderinas/farmacologia , Espaço Extracelular/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Western Blotting , Caderinas/antagonistas & inibidores , Adesão Celular/efeitos dos fármacos , Dimerização , Espaço Extracelular/efeitos dos fármacos , Células HEK293 , Humanos , Imunoprecipitação , Indicadores e Reagentes , Plasmídeos/genética , Transfecção
12.
Stem Cell Res ; 53: 102274, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33714066

RESUMO

Idiopathic basal ganglia calcification (IBGC) is a rare neurodegenerative disease, characterized by abnormal calcium deposits in basal ganglia of the brain. The affected individuals exhibit movement disorders, and progressive deterioration of cognitive and psychiatric ability. The genetic cause of the disease is mutation in one of several different genes, SLC20A2, PDGFB, PDGFRB, XPR1 or MYORG, which inheritably or sporadically occurs. Here we generated an induced pluripotent stem cell (iPSC) line from an IBGC patient, which is likely be a powerful tool for revealing the pathomechanisms and exploring potential therapeutic candidates of IBGC.


Assuntos
Doenças dos Gânglios da Base , Células-Tronco Pluripotentes Induzidas , Doenças Neurodegenerativas , Gânglios da Base/metabolismo , Doenças dos Gânglios da Base/genética , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Mutação , Doenças Neurodegenerativas/genética , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/genética , Receptor do Retrovírus Politrópico e Xenotrópico
13.
Stroke ; 41(8): 1798-806, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20595663

RESUMO

BACKGROUND AND PURPOSE: The effect of telmisartan, an angiotensin II Type 1 receptor blocker with peroxisome proliferator-activated receptor-gamma-modulating activity, was investigated against spatial working memory disturbances in mice subjected to chronic cerebral hypoperfusion. METHODS: Adult C57BL/6J male mice were subjected to bilateral common carotid artery stenosis using external microcoils. Mice received a daily oral administration of low-dose telmisartan (1 mg/kg per day), high-dose telmisartan (10 mg/kg per day), or vehicle with or without peroxisome proliferator-activated receptor-gamma antagonist GW9662 (1 mg/kg per day) for all treatments for 30 days after bilateral common carotid artery stenosis. Cerebral mRNA expression of monocyte chemoattractant protein-1 and tumor necrosis factor-alpha was measured 30 days after bilateral common carotid artery stenosis, and postmortem brains were analyzed for demyelinating change with Klüver-Barrera staining and immunostained for glial, oxidative stress, and vascular endothelial cell markers. Spatial working memory was assessed by the Y-maze test. RESULTS: Mean systolic blood pressure and cerebral blood flow did not decrease with low-dose telmisartan but significantly decreased with high-dose telmisartan. Low-dose telmisartan significantly attenuated, but high-dose telmisartan provoked, spatial working memory impairment with glial activation, oligodendrocyte loss, and demyelinating change in the white matter. Such positive effects of low-dose telmisartan were partially offset by cotreatment with GW9662. Consistent with this, low-dose telmisartan reduced the degree of oxidative stress of vascular endothelial cells and the mRNA levels of monocyte chemoattractant protein-1 and tumor necrosis factor-alpha compared with vehicle. CONCLUSIONS: Anti-inflammatory and antioxidative effects of telmisartan that were exerted in part by peroxisome proliferator-activated receptor-gamma activation, but not its blood pressure-lowering effect, have protective roles against cognitive impairment and white matter damage after chronic cerebral hypoperfusion.


Assuntos
Benzimidazóis/farmacologia , Benzoatos/farmacologia , Estenose das Carótidas/metabolismo , Transtornos Cognitivos/tratamento farmacológico , Cognição/efeitos dos fármacos , PPAR gama/metabolismo , Análise de Variância , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Anilidas/farmacologia , Animais , Benzimidazóis/uso terapêutico , Benzoatos/uso terapêutico , Artéria Carótida Primitiva , Estenose das Carótidas/complicações , Estenose das Carótidas/tratamento farmacológico , Córtex Cerebral/metabolismo , Quimiocina CCL2/metabolismo , Transtornos Cognitivos/complicações , Transtornos Cognitivos/metabolismo , Imuno-Histoquímica , Masculino , Memória de Curto Prazo/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Oligodendroglia/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , PPAR gama/antagonistas & inibidores , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Comportamento Espacial/efeitos dos fármacos , Telmisartan , Fator de Necrose Tumoral alfa/metabolismo
14.
Biochem Biophys Res Commun ; 393(4): 728-33, 2010 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-20171164

RESUMO

We previously indicated that amyloid beta (Abeta) augments protein levels of beta-site amyloid precursor protein cleaving enzyme-1 (BACE-1) through oxidative stress. In this study, we revealed that BACE-1 is involved in the cleavage of membrane-bound prostaglandin E2 synthase-2 (mPGES-2) in its N-terminal portion, which, in turn, enhanced the generation of prostaglandin E2 (PGE2). PGE2 results in increased Abeta production, initiating a cell-injuring cycle. Using rat primary cortical neurons, a 48 h treatment with Abeta 1-42 (5 microM) resulted in the enhanced extracellular PGE2 levels up to about 1 ng/mL, which was attenuated by treatment with a BACE-1 inhibitor (200 nM). A synthetic peptide sequence of 20-amino acids that included the cleavage site of mPGES-2 (HTARWHL RAQDLHERS AAQLSLSS) was cleaved by recombinant BACE-1, confirmed using reverse-phase high-performance liquid chromatography. Cleaved or activated mPGES-2 augments the generation of PGE2. In addition, mPGES-2 was determined to be colocalized with BACE-1 and cyclooxygenase-2 in the perinuclear region in cells after exposure to Abeta. Exposure of neurons to PGE2 led to cell death, and Abeta production was enhanced by PGE2 (1 ng/mL, 48 h). Collectively, these results suggest that Abeta might cause neuroinflammation that aggravates Alzheimer's disease pathogenesis.


Assuntos
Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Oxirredutases Intramoleculares/metabolismo , Neurônios/metabolismo , Sequência de Aminoácidos , Secretases da Proteína Precursora do Amiloide/genética , Peptídeos beta-Amiloides/farmacologia , Animais , Apoptose , Ciclo-Oxigenase 2/metabolismo , Humanos , Oxirredutases Intramoleculares/genética , Dados de Sequência Molecular , Neurônios/efeitos dos fármacos , Prostaglandina-E Sintases , Ratos
15.
Biochem Biophys Res Commun ; 393(3): 514-8, 2010 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-20152809

RESUMO

Reduction in or dysfunction of glutamate transporter 1 (GLT1) is linked to several neuronal disorders such as stroke, Alzheimer's disease, and amyotrophic lateral sclerosis. However, the detailed mechanism underlying GLT1 regulation has not been fully elucidated. In the present study, we first demonstrated the effects of mammalian target of rapamycin (mTOR) signaling on GLT1 regulation. We prepared astrocytes cultured in astrocyte-defined medium (ADM), which contains several growth factors including epidermal growth factor (EGF) and insulin. The levels of phosphorylated Akt (Ser473) and mTOR (Ser2448) increased, and GLT1 levels were increased in ADM-cultured astrocytes. Treatment with a phosphatidylinositol 3-kinase (PI3K) inhibitor or an Akt inhibitor suppressed the phosphorylation of Akt (Ser473) and mTOR (Ser2448) as well as decreased ADM-induced GLT1 upregulation. Treatment with the mTOR inhibitor rapamycin decreased GLT1 protein and mRNA levels. In contrast, rapamycin did not affect Akt (Ser473) phosphorylation. Our results suggest that mTOR is a downstream target of the PI3K/Akt pathway regulating GLT1 expression.


Assuntos
Astrócitos/metabolismo , Transportador 2 de Aminoácido Excitatório/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Células Cultivadas , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Ratos , Ratos Wistar , Serina-Treonina Quinases TOR
16.
Biochem Biophys Res Commun ; 391(2): 1240-5, 2010 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-20006583

RESUMO

gamma-Secretase is an enzymatic complex, composed of presenilin 1 (PS1), nicastrin, pen-2, and aph-1, and is responsible for the intramembranous cleavage of various type-I membrane proteins. The level of each component is tightly regulated in a cell via proteasomal degradation. On the other hand, it has previously been reported that PS1/gamma-secretase is involved in the activation of phosphatidylinositol-3 kinase/Akt (PI3K/Akt) pathway. PI3K is inhibited in Alzheimer's disease (AD) brain, whereas the effects of PI3K inhibition on the metabolism of PS1/gamma-secretase have not been elucidated. Here, we demonstrate that the treatment of neurons with PI3K inhibitors leads to increased levels of PS1/gamma-secretase components through an inhibitory effect on their degradation. Moreover, PI3K inhibition accelerated ubiquitination of PS1. We further show the evidence that the PS1 ubiquitination after PI3K inhibition is represented by the multiple mono-ubiquitination, instead of poly-ubiquitination. Accordingly, treatment of cells with PI3K inhibitor led to a differential intracellular redistribution of PS1 from the one observed after the proteasomal inhibition. These results suggest that PI3K inhibition may trigger the multiple mono-ubiquitination of PS1, which precludes the degradation of PS1/gamma-secretase through the proteasomal pathway. Since PS1/gamma-secretase is deeply involved in the production of Abeta protein, a deeper knowledge into its metabolism could contribute to a better elucidation of AD pathogenesis.


Assuntos
Neurônios/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Presenilina-1/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina/metabolismo , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Humanos , Camundongos , Neurônios/efeitos dos fármacos , Inibidores de Fosfoinositídeo-3 Quinase , Ubiquitinação
18.
Bioorg Med Chem Lett ; 20(5): 1718-20, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20137934

RESUMO

We synthesized a series of N(1)-substituted norcymserine derivatives 7a-p and evaluated their anti-cholinesterase activities. In vitro evaluation showed that the pyridinylethyl derivatives 7m-o and the piperidinylethyl derivative 7p improved the anti-butyrylcholinesterase activity by approximately threefold compared to N(1)-phenethylnorcymserine (PEC, 2). A quantitative structure-activity relationship (QSAR) study indicated that logS might be a key feature of the improved compounds.


Assuntos
Butirilcolinesterase/química , Carbamatos/síntese química , Inibidores da Colinesterase/síntese química , Fármacos Neuroprotetores/síntese química , Fisostigmina/análogos & derivados , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Butirilcolinesterase/metabolismo , Carbamatos/química , Carbamatos/farmacologia , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Desenho de Fármacos , Humanos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Fisostigmina/química , Relação Quantitativa Estrutura-Atividade
19.
Biochim Biophys Acta ; 1780(5): 819-25, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18295609

RESUMO

Generation and accumulation of the amyloid beta peptide (Abeta) following proteolytic processing of the amyloid precursor protein (APP) by BACE-1 (Beta-site APP Cleaving Enzyme-1, beta-secretase) and gamma-secretase is a main causal factor of Alzheimer's disease (AD). Consequently, inhibition of BACE-1, a rate-limiting enzyme in the production of Abeta, is an attractive therapeutic approach for the treatment of AD. In this study, we discovered that natural flavonoids act as non-peptidic BACE-1 inhibitors and potently inhibit BACE-1 activity and reduce the level of secreted Abeta in primary cortical neurons. In addition, we demonstrated the calculated docking poses of flavonoids to BACE-1 and revealed the interactions of flavonoids with the BACE-1 catalytic center. We firstly revealed novel pharmacophore features of flavonoids by using cell-free, cell-based and in silico docking studies. These results contribute to the development of new BACE-1 inhibitors for the treatment of AD.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Flavonas/farmacologia , Flavonóis/farmacologia , Modelos Moleculares , Inibidores de Proteases/farmacologia , Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/química , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Apigenina/química , Apigenina/farmacologia , Ácido Aspártico Endopeptidases/química , Ácido Aspártico Endopeptidases/metabolismo , Domínio Catalítico , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/citologia , Flavonas/química , Flavonoides/química , Flavonoides/farmacologia , Flavonóis/química , Humanos , Ligação de Hidrogênio , Quempferóis/química , Quempferóis/farmacologia , Estrutura Molecular , Neurônios/efeitos dos fármacos , Neurônios/enzimologia , Neurônios/metabolismo , Inibidores de Proteases/química , Quercetina/química , Quercetina/farmacologia , Ratos , Relação Estrutura-Atividade
20.
J Neurochem ; 109(5): 1324-37, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19476545

RESUMO

The accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) is known to activate the ER, which is termed ER stress. Here, we demonstrated that amyloid precursor protein (APP) is a novel mediator of ER stress-induced apoptosis through the C/EBP homologous protein (CHOP) pathway. Expression of APP mRNA was elevated by tunicamycin- or dithiothreitol-induced ER stress. The levels of C83 and APP intracellular domain (AICD) fragments, which are cleaved from APP, were significantly increased under ER stress, although the protein level of full-length APP was decreased. Cellular viability was reduced in APP-over-expressing cells, which was attenuated by treatment with a gamma-secretase inhibitor, N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (DAPT). Cellular viability was also reduced in AICD-FLAG-over-expressing cells. The mRNA and protein levels of CHOP, an ER stress-responsive gene, were remarkably increased by APP over-expression, which was attenuated by treatment with DAPT. CHOP mRNA induction was also found in AICD-FLAG-over-expressing cells. Cell death and CHOP up-regulation by ER stress were attenuated by APP knockdown. Data obtained with a luciferase assay and chromatin immunoprecipitation assay indicated that AICD associates with the promoter region of the CHOP gene. In conclusion, ER stress-induced APP undergoes alpha- and gamma-secretase cleavage and subsequently induces CHOP-mediated cell death.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Retículo Endoplasmático/metabolismo , Transdução de Sinais/fisiologia , Estresse Fisiológico/efeitos dos fármacos , Fator de Transcrição CHOP/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Morte Celular/efeitos dos fármacos , Linhagem Celular/ultraestrutura , Imunoprecipitação da Cromatina/métodos , Dipeptídeos/farmacologia , Ditiotreitol/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Humanos , L-Lactato Desidrogenase/metabolismo , Neuroblastoma , Ácidos Prostanoicos/metabolismo , Estrutura Terciária de Proteína/fisiologia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção , Tunicamicina/farmacologia , Tirosina/metabolismo
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