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1.
Nutrients ; 16(2)2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38257087

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease that involves progressive cognitive decline accompanied by synaptic degeneration and impaired neurotransmission. Recent studies revealed that apple pomace, a waste byproduct of the apple processing industry, has beneficial health properties, but its potential to prevent and treat AD has not been determined. Herein, we examined the effects of apple pomace extract on N-methyl-D-aspartate receptor antagonist MK-801-induced memory impairment in mice. Repeated treatment with apple pomace extract for 7 days reversed the MK-801-induced impairment of associative memory and recognition memory. RNA sequencing revealed that repeated treatment with apple pomace extract altered the gene expression profile in the hippocampus of mice. Real-time PCR showed that apple pomace extract induced upregulation of the mRNA expression for Zfp125 and Gstp1. Furthermore, gene sets related to synapse and neurotransmission were upregulated by apple pomace extract. These findings indicate that apple pomace extract may be useful for the prevention and treatment of AD.


Assuntos
Doença de Alzheimer , Malus , Doenças Neurodegenerativas , Animais , Camundongos , Maleato de Dizocilpina , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/prevenção & controle , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Proteínas de Ligação a DNA
2.
Int J Biol Macromol ; 246: 125555, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37364807

RESUMO

Polysaccharides, an important class of carbohydrate polymers, are considered as one of the sources of drug molecules. To discover bioactive polysaccharides as potential agents against cancer, a homogeneous polysaccharide (IJP70-1) has been purified from the flowers of Inula japonica, which is a traditional medicinal plant used for various medical indications. IJP70-1 with a molecular weight of 1.019 × 105 Da was mainly composed of →5)-α-l-Araf-(1→, →2,5)-α-l-Araf-(1→, →3,5)-α-l-Araf-(1→, →2,3,5)-α-l-Araf-(1→, →6)-α-d-Glcp-(1→, →3,6)-α-d-Galp-(1→, and t-α-l-Araf. Apart from the characteristics and structure elucidated by various techniques, the in vivo antitumor activity of IJP70-1 was assayed using zebrafish models. In the subsequent mechanism investigation, it was found that the in vivo antitumor activity of IJP70-1 was not cytotoxic mechanism caused, but related to the activation of the immune system and inhibition of angiogenesis by interacting with the proteins toll-like receptor-4 (TLR-4), programmed death receptor-1 (PD-1), and vascular endothelial growth factor (VEGF). The chemical and biological studies have shown that the homogeneous polysaccharide IJP70-1 has the potential to be developed into an anticancer agent.


Assuntos
Antineoplásicos , Inula , Animais , Fator A de Crescimento do Endotélio Vascular , Receptor de Morte Celular Programada 1 , Receptor 4 Toll-Like , Peixe-Zebra , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Fatores de Crescimento do Endotélio Vascular , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Polissacarídeos/química
3.
J Food Biochem ; 46(10): e14295, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35790009

RESUMO

Alzheimer's disease (AD) is associated with a progressive worsening in cognitive function, which is often accompanied by emotional disturbance. Recent studies revealed that anthocyanin-rich blackcurrant extract (BCE) can impart health benefits, but it is not known whether BCE is useful in the prevention and/or treatment of AD. Here, we examined the effects of BCE using a senescence-accelerated mouse prone 8 (SAMP8) model. Dietary BCE supplementation for 9 weeks was found to both improve the diminished long-term recognition memory and normalize the anxiety levels of SAMP8 mice. RNA sequencing demonstrated that dietary supplementation with anthocyanin-rich BCE significantly altered the gene expression profile in the hippocampus. According to enrichment analysis, genes regulated by BCE were related to cellular component terms such as "smooth endoplasmic reticulum," "axon," and "glutamatergic synapse." Real-time PCR verified alterations in the expression of AD-related genes. These findings indicate that anthocyanin-rich BCE may be valuable for the prevention and/or treatment of AD. PRACTICAL APPLICATIONS: Blackcurrant contains an abundance of polyphenols, especially anthocyanins. This study demonstrated that anthocyanin-rich BCE improves the long-term recognition memory impairment and emotional abnormality of SAMP8 mice, a mouse model characterized by several pathological features of AD. These findings indicate that anthocyanin-rich BCE may be a useful food supplement or ingredient for the prevention of AD.


Assuntos
Doença de Alzheimer , Ribes , Doença de Alzheimer/tratamento farmacológico , Animais , Antocianinas/farmacologia , Modelos Animais de Doenças , Memória de Longo Prazo , Camundongos , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Polifenóis/análise
4.
Nutrients ; 14(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35565814

RESUMO

As life expectancy increases, age-associated diseases such as Alzheimer's disease (AD) become a major health problem. The onset of AD involves neurological dysfunction due to amyloid-ß accumulation, tau hyperphosphorylation, oxidative stress, and neuroinflammation in the brain. In addition, lifestyle-related diseases-such as dyslipidemia, diabetes, obesity, and vascular dysfunction-increase the risk of developing dementia. The world population ages, prompting the development of new strategies to maintain brain health and prevent the onset of dementia in older and preclinical patients. Citrus fruits are abundant polymethoxylated flavone and flavanone sources. Preclinical studies reported that these compounds have neuroprotective effects in models of dementia such as AD. Interestingly, clinical and epidemiological studies appear to support preclinical evidence and show improved cognitive function and reduced associated disease risk in healthy individuals and/or patients. This review summarizes the recent evidence of the beneficial effects of citrus peels and extracts on human cognition and related functions.


Assuntos
Doença de Alzheimer , Citrus , Idoso , Doença de Alzheimer/metabolismo , Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Citrus/metabolismo , Humanos , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
5.
Regul Toxicol Pharmacol ; 114: 104670, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32371103

RESUMO

Nobiletin and tangeretin are major components of polymethoxylated flavones in the peels of citrus fruits such as Citrus reticulata. Because nobiletin and tangeretin have attracted attention due to their beneficial health properties, citrus peel extracts, in which they are concentrated, have the potential to serve as a functional food ingredient to prevent diseases. In this study, a series of toxicological studies on the peel extract of Ponkan cultivar 'Ohta ponkan' (Citrus reticulata Blanco), was conducted. No mutagenic activity was observed in a bacterial reverse mutation test, whereas chromosomal aberrations were induced in an in vitro mammalian chromosomal aberration test. No genotoxicity was observed in an in vivo mammalian micronucleus test. In a 90-day study at daily doses of 54, 180, or 540 mg/kg body weight (bw)/day, hyaline droplet nephropathy, which specifically occurs in adult male rats, was observed in males of 540 mg/kg bw/day group. No other adverse effects were observed in the 90-day study. The no adverse effect level in the 90-day study was considered to be 540 mg/kg bw/day for female rats and less than 540 mg/kg bw/day for male rats.


Assuntos
Citrus/química , Flavonas/toxicidade , Nootrópicos/toxicidade , Extratos Vegetais/toxicidade , Plantas Medicinais/toxicidade , Administração Oral , Doença de Alzheimer/tratamento farmacológico , Animais , Peso Corporal/efeitos dos fármacos , Aberrações Cromossômicas/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Flavonas/administração & dosagem , Flavonas/química , Alimento Funcional/efeitos adversos , Alimento Funcional/toxicidade , Masculino , Testes para Micronúcleos , Nootrópicos/administração & dosagem , Nootrópicos/química , Doença de Parkinson/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Plantas Medicinais/química , Ratos , Ratos Sprague-Dawley
6.
Int J Mol Sci ; 20(14)2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295812

RESUMO

Alzheimer's disease (AD), which is characterized by the presence of amyloid-ß (Aß) plaques and neurofibrillary tangles, accompanied by neurodegeneration, is the most common form of age-related neurodegenerative disease. Parkinson's disease (PD) is the second most common neurodegenerative disease after AD, and is characterized by early prominent loss of dopaminergic neurons in the substantia nigra pars compacta. As currently available treatments are not able to significantly alter the progression of these diseases, successful therapeutic and preventive interventions are strongly needed. In the course of our survey of substances from natural resources having anti-dementia and neuroprotective activity, we found nobiletin, a polymethoxylated flavone from the peel of Citrus depressa. Nobiletin improved cognitive deficits and the pathological features of AD, such as Aß pathology, hyperphosphorylation of tau, and oxidative stress, in animal models of AD. In addition, nobiletin improved motor and cognitive deficits in PD animal models. These observations suggest that nobiletin has the potential to become a novel drug for the treatment and prevention of neurodegenerative diseases such as AD and PD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Citrus/química , Flavonas/farmacologia , Flavonoides/farmacologia , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson/tratamento farmacológico , Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/prevenção & controle , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Biomarcadores , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Flavonas/química , Flavonas/uso terapêutico , Flavonoides/química , Flavonoides/uso terapêutico , Humanos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Doença de Parkinson/etiologia , Doença de Parkinson/metabolismo , Doença de Parkinson/prevenção & controle , Transdução de Sinais/efeitos dos fármacos
7.
J Hazard Mater ; 378: 120610, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31226590

RESUMO

After powder of La2Mo2O9 (LMO) was prepared using complex polymerization, dense sintered bodies (96% relative density) of LMO were obtained from the powder through pressureless sintering in a synthesized air atmosphere. The water contact angle of the LMO ceramics increased gradually during storage in ambient air. It reached 93.6 ± 3.0° in 624 h. Results of XPS analysis and ozone treatment suggest that organic substances in ambient air adsorbed onto the LMO surface during storage. Measurements of antibacterial (Escherichia coli and Staphylococcus aureus) and antiviral (bacteriophage Qß and bacteriophage Φ6) activities of LMO revealed that their survival rates decreased more than 99.9% within 6 h. Based on results obtained using dissolved ion contact method and from comparison of the antibacterial and antiviral activities with La2O3 and MoO3, one can infer that the synergistic effect of La2O3 and MoO3 plays an important role in the high antibacterial and antiviral activity of LMO.


Assuntos
Antibacterianos/farmacologia , Antivirais/farmacologia , Cerâmica/química , Lantânio/química , Carbono/química , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Escherichia coli/efeitos dos fármacos , Íons , Testes de Sensibilidade Microbiana , Molibdênio/química , Polimerização , Pós , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Água/farmacologia , Difração de Raios X
8.
Arch Oral Biol ; 84: 19-28, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28938197

RESUMO

OBJECTIVES: Osteogenic protein-1 (OP-1) has shown osteoinductive activities and is useful for clinical treatments, including bone regeneration. Regenerative procedures using a bioabsorbable collagen membrane (BCM) are well established in periodontal and implant dentistry. We evaluated the subsequent effects of the BCM in combination with OP-1 on bone regeneration in a rat mandibular circular critical-sized bone defect in vivo. DESIGN: We used 8 rats that received surgery in both sides of the mandible, and created the total 16 defects which were divided into 4 groups: Group 1; no treatment, as a control, Group 2; BCM alone, Group 3; BCM containing low dose 0.5µg of OP-1 (L-OP-1), and Group 4; BCM containing high dose 2.0µg of OP-1 (H-OP-1). Newly formed bone was evaluated by micro computed tomography (micro-CT) and histological analyses at 8 weeks postoperatively. In quantitative and qualitative micro-CT analyses of the volume of new bone formation, bone density, and percentage of new bone area was evaluated. RESULTS: BCM with rhOP-1 significantly increased and accelerated bone volume, bone mineral density, and percentage of new bone area compared to control and BCM alone at 8 weeks after surgery; these enhancements in bone regeneration in the OP-1-treated groups were dose-dependent. CONCLUSIONS: OP-1 delivered with a BCM may have effective osteoinductive potency and be a good combination for bone regeneration. The use of such a combination device for osteogenesis may result in safer and more predictable bone regenerative outcomes in the future.


Assuntos
Proteína Morfogenética Óssea 7/farmacologia , Regeneração Óssea/efeitos dos fármacos , Colágeno/farmacologia , Mandíbula/cirurgia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Masculino , Mandíbula/diagnóstico por imagem , Membranas Artificiais , Osteoblastos/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344 , Microtomografia por Raio-X
9.
Behav Brain Res ; 250: 351-60, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23714077

RESUMO

Senescence-accelerated mouse prone 8 (SAMP8) is a model of aging characterized by the early onset of learning and memory impairment and various pathological features of Alzheimer's disease (AD). Our recent studies have demonstrated that nobiletin, a polymethoxylated flavone from citrus peels, ameliorates learning and memory impairment in olfactory-bulbectomized mice, amyloid precursor protein transgenic mice, and NMDA receptor antagonist-treated mice. Here, we present evidence that this natural compound improves age-related cognitive impairment and reduces oxidative stress and tau phosphorylation in SAMP8 mice. Treatment with nobiletin (10 or 50mg/kg) reversed the impairment of recognition memory and context-dependent fear memory in SAMP8 mice. Treatment with nobiletin also restored the decrease in the GSH/GSSG ratio in the brain of SAMP8 mice. In addition, increases in glutathione peroxidase and manganese-superoxide dismutase activities, as well as a decrease in protein carbonyl level, were observed in the brain of nobiletin-treated SAMP8 mice. Furthermore, nobiletin reduced tau phosphorylation in the hippocampus of SAMP8 mice. Together, the markedly beneficial effects of nobiletin represent a potentially useful treatment for ameliorating the learning and memory deficits, oxidative stress, and hyperphosphorylation of tau in aging as well as age-related neurodegenerative diseases such as AD.


Assuntos
Envelhecimento/efeitos dos fármacos , Antioxidantes/uso terapêutico , Transtornos Cognitivos/tratamento farmacológico , Flavonas/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Proteínas tau/metabolismo , Envelhecimento/genética , Envelhecimento/fisiologia , Análise de Variância , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Peso Corporal/efeitos dos fármacos , Peso Corporal/genética , Estudos de Casos e Controles , Condicionamento Psicológico/efeitos dos fármacos , Condicionamento Psicológico/fisiologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Comportamento Exploratório/efeitos dos fármacos , Medo/efeitos dos fármacos , Medo/fisiologia , Flavonas/química , Flavonas/farmacologia , Glutationa/metabolismo , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Transgênicos , Fosforilação/efeitos dos fármacos , Carbonilação Proteica/efeitos dos fármacos , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
10.
J Neural Transm (Vienna) ; 120(10): 1397-409, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23588349

RESUMO

cAMP/PKA/ERK/CREB signaling linked to CRE-mediated transcription is crucial for learning and memory. We originally found nobiletin as a natural compound that stimulates this intracellular signaling and exhibits anti-dementia action in animals. Citrus reticulata or C. unshiu peels are employed as "chinpi" and include a small amount of nobiletin. We here provide the first evidence for beneficial pharmacological actions on the cAMP/PKA/ERK/CREB cascade of extracts from nobiletin-rich C.reticulata peels designated as Nchinpi, the nobiletin content of which was 0.83 ± 0.13% of the dry weight or 16-fold higher than that of standard chinpi extracts. Nchinpi extracts potently facilitated CRE-mediated transcription in cultured hippocampal neurons, whereas the standard chinpi extracts showed no such activity. Also, the Nchinpi extract, but not the standard chinpi extract, stimulated PKA/ERK/CREB signaling. Interestingly, treatment with the Nchinpi extract at the concentration corresponding to approximately 5 µM nobiletin more potently facilitated CRE-mediated transcriptional activity than did 30 µM nobiletin alone. Consistently, sinensetin, tangeretin, 6-demethoxynobiletin, and 6-demethoxytangeretin were also identified as bioactive substances in Nchinpi that facilitated the CRE-mediated transcription. Purified sinensetin enhanced the transcription to a greater degree than nobiletin. Furthermore, samples reconstituted with the four purified compounds and nobiletin in the ratio of each constituent's content in the extract showed activity almost equal to that of the Nchinpi extract to stimulate CRE-mediated transcription. These findings suggest that above four compounds and nobiletin in the Nchinpi extract mainly cooperated to facilitate potently CRE-mediated transcription linked to the upstream cAMP/PKA/ERK/CREB pathway in hippocampal neurons.


Assuntos
Citrus/química , Medicamentos de Ervas Chinesas/farmacologia , Flavonas/farmacologia , Hipocampo/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Western Blotting , Células Cultivadas , Cromatografia Líquida de Alta Pressão , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Frutas/química , Hipocampo/fisiologia , Aprendizagem/fisiologia , Medicina Kampo , Memória/fisiologia , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley , Transfecção
11.
Br J Nutr ; 107(10): 1452-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21917197

RESUMO

The present study was designed to investigate the effect of pectin on Fe bioavailability in ileorectomised rats or caecectomised rats. In Expt 1, rats were divided into the following two groups: ileorectomised rats fed a fibre-free diet (FF diet) and ileorectomised rats fed a FF diet supplemented with 5 % (w/w) pectin (pectin diet). Apparent Fe absorption in ileorectomised rats fed the pectin diet was significantly lower compared with ileorectomised rats fed the FF diet. In Expt 2, caecectomised rats and sham-operated rats were given one of the following diets for 3 weeks: diet containing ferrous iron (FeII diet), diet containing pectin at 50 g/kg diet (pectin diet) and diet containing a mixture of FeII and product prepared by the enzymatic degradation of pectin (FeII-OGA diet), which were presumed to be oligomers of galacturonic acid. The Fe content of these diets was 7·6, 8·1 and 7·7 mg/kg diet, respectively. The bioavailability of Fe in rats fed the FeII diet was not affected by caecectomy. In contrast, in rats fed the pectin diet, where Fe bound to pectin was the only Fe source, Hb gain and Hb regeneration efficiency were significantly decreased by caecectomy. The bioavailability of Fe from the FeII-OGA complex was not affected by caecectomy. These results suggest that Fe in pectin might be released by microbial degradation and subsequently made available for absorption in the large intestine, although pectin might decrease Fe absorption in the small intestine.


Assuntos
Ceco/metabolismo , Fibras na Dieta/metabolismo , Hemoglobinas/metabolismo , Intestino Delgado/efeitos dos fármacos , Ferro da Dieta/farmacocinética , Ferro/farmacocinética , Pectinas/metabolismo , Animais , Disponibilidade Biológica , Ceco/efeitos dos fármacos , Ceco/cirurgia , Dieta , Fibras na Dieta/farmacologia , Suplementos Nutricionais , Compostos Ferrosos/metabolismo , Absorção Intestinal , Intestino Grosso/efeitos dos fármacos , Intestino Grosso/metabolismo , Intestino Grosso/cirurgia , Intestino Delgado/metabolismo , Intestino Delgado/cirurgia , Masculino , Pectinas/farmacologia , Ratos , Ratos Wistar
12.
Br J Nutr ; 106(1): 73-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21521538

RESUMO

In the present in vitro study, the effects of pH and ionic strength on the release of iron from pectin and the ability of pectin to reduce ferric iron to ferrous iron were examined. The bioavailability of Fe bound to pectin was evaluated in rats. The amount of Fe released from pectin was at a maximum at pH 2·0 and decreased as the pH value increased. At pH 2·0, the amount of Fe released from pectin increased as the ion length increased; at pH 5·0, ion length had no effect on pectin release. Pectin effectively reduced Fe from the ferric form to the ferrous form. In rats fed a pectin diet, where Fe bound to pectin was the only Fe source, the final Hb concentration using diets containing 4·4-5·7, 7·2 or 11·5 mg Fe/kg diet was equal to the concentration in rats fed diets containing 4·5, 7·6 or 13·5 mg ferrous iron/kg diet, respectively. Hb regeneration efficiencies in rats fed pectin diets were significantly different from rats fed a diet containing 13·5 mg ferrous iron/kg diet. In rats fed a diet with or without pectin, where ferric iron was the only Fe source, pectin increased the final Hb concentration. These results suggest that Fe bound to pectin is utilised by rats.


Assuntos
Ferro/metabolismo , Pectinas/metabolismo , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Concentração de Íons de Hidrogênio , Ferro/química , Masculino , Concentração Osmolar , Pectinas/química , Ratos , Ratos Wistar , Aumento de Peso/efeitos dos fármacos
13.
Yakugaku Zasshi ; 130(4): 517-20, 2010 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-20371995

RESUMO

Alzheimer's disease (AD) has become a major health burden to society. However, no fundamentally therapeutic drugs for AD have been developed. Increasing evidence suggests that the elevation of beta-amyloid (Abeta) peptides in the brain is central to AD pathogenesis. Recently, in the course of our survey of substances having anti-dementia activity from natural resources, we have successfully found nobiletin, a polymethoxylated flavone contained in AURANTII NOBILIS PERICARPIUM which is a component of traditional Chinese medicines. In this review, we describe the beneficial effects of nobiletin on memory impairment and Abeta pathology in a transgenic mouse model introduced human "Swedish" and "London" mutant amyloid precursor protein. We also note the possible molecular mechanism underlying the protective action against Abeta-induced memory impairment provided by our studies using cultured hippocampal neurons. Namely, daily administration of nobiletin for four months rescued the memory impairment in fear conditioning, and decreased hippocampal Abeta deposit in the transgenic mice as analyzed by immunohistochemistry. PKA-dependent signaling and membrane trafficking of AMPA receptor subunit, GluR1, which are known to be required for long-term potentiation (LTP), have been demonstrated to be inhibited by a sublethal concentration of Abeta in cultured hippocampal neurons. Our in vitro studies evidently showed that a sublethal concentration of Abeta actually inhibited glutamate-induced increases in both PKA substrates phosphorylation and GluR1 membrane trafficking in cultured hippocampal neurons, whereas nobiletin reversed the Abeta-induced inhibition of such biochemical processes. The natural compound with these unique actions has thus potential to become a novel drug for fundamental treatment of AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Antioxidantes/uso terapêutico , Flavonas/uso terapêutico , Transtornos da Memória/tratamento farmacológico , Plantas Medicinais/química , Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Descoberta de Drogas , Flavonas/isolamento & purificação , Flavonas/farmacologia , Hipocampo/metabolismo , Humanos , Potenciação de Longa Duração , Camundongos , Receptores de AMPA/metabolismo
14.
J Hazard Mater ; 169(1-3): 697-702, 2009 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-19428184

RESUMO

Fe(2)O(3)/Al(2)O(3) powders with a range of Fe/Al compositions were prepared by a gel evaporation method to investigate the effect of alumina on the product phases, magnetic properties and simultaneous adsorption of Ni(2+) (a model heavy metal cation), NH(4)(+) (a model eutrophication-related cation) and H(2)PO(4)(-) (a model harmful anion). Precursor gels were prepared by dissolving Fe(NO(3))(3).9H(2)O and Al(NO(3))(3).9H(2)O in ethylene glycol, evaporating to dryness, grinding and heating at 300-1000 degrees C for 5h. The crystalline products were gamma-Fe(2)O(3) (maghemite), formed at 300-600 degrees C, or alpha-Fe(2)O(3) (hematite) and AlFeO(3), formed >600 degrees C. The temperatures of the phase change from gamma-Fe(2)O(3) to alpha-Fe(2)O(3) increased with increasing alumina additions. The resulting lattice parameters suggest that Al(3+) is incorporated into these phases up to about 15 mol.% at 300 degrees C, falling to 11 mol.% in the gamma-Fe(2)O(3) formed at 600 degrees C. The alpha-Fe(2)O(3) formed at 700 degrees C contained 6 mol.% Al, increasing to 14 mol.% at 1000 degrees C. The magnetic properties of the samples were measured using a vibrating sample magnetometer. The saturation magnetization values of the gamma-Fe(2)O(3)-containing samples increased with the addition of alumina to a maximum value of 61emu/g in the sample containing 95 mol.% Fe(2)O(3) heated at 400 degrees C. The simultaneous adsorption of Ni(2+), NH(4)(+) and H(2)PO(4)(-) from water was investigated by a batch method. The highest adsorption values were found for the sample containing 80 mol.% Fe(2)O(3) heated at 600 degrees C, which contained both gamma-Fe(2)O(3) and alpha-Fe(2)O(3). It was therefore concluded that the addition of alumina to iron oxide affects the crystalline phases and phase changes, and enhances the simultaneous cation and anion uptake ability of the materials.


Assuntos
Óxido de Alumínio/química , Amônia/isolamento & purificação , Compostos Férricos/química , Níquel/isolamento & purificação , Ácidos Fosfóricos/isolamento & purificação , Adsorção , Cristalização , Géis , Íons , Magnetismo , Transição de Fase , Pós
16.
J Pharmacol Exp Ther ; 326(3): 739-44, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18544674

RESUMO

Increasing evidence suggests that the elevation of beta-amyloid (Abeta) peptides in the brain is central to the pathogenesis of Alzheimer's disease (AD). Our recent studies have demonstrated that nobiletin, a polymethoxylated flavone from citrus peels, enhances cAMP/protein kinase A/extracellular signal-regulated kinase/cAMP response element-binding protein signaling in cultured hippocampal neurons and ameliorates Abeta-induced memory impairment in AD model rats. For the first time, we report that this natural compound improves memory deficits in amyloid precursor protein (APP) transgenic mice that overexpress human APP695 harboring the double Swedish and London mutations [APP-SL 7-5 transgenic (Tg) mice]. Our enzyme-linked immunosorbent assay (ELISA) also showed that administration of nobiletin to the transgenic mice for 4 months markedly reduced quantity of guanidine-soluble Abeta(1-40) and Abeta(1-42) in the brain. Furthermore, consistent with the results of ELISA, by immunohistochemistry with anti-Abeta antibody, it was evidently shown that the administration of nobiletin decreased the Abeta burden and plaques in the hippocampus of APP-SL 7-5 Tg mice. These findings suggest that this natural compound has potential to become a novel drug for fundamental treatment of AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/fisiologia , Modelos Animais de Doenças , Flavonas/uso terapêutico , Flavonoides/uso terapêutico , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/metabolismo , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/biossíntese , Peptídeos beta-Amiloides/genética , Animais , Citrus , Flavonas/química , Flavonoides/química , Transtornos da Memória/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
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