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1.
Molecules ; 26(12)2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34205249

RESUMO

The accumulation and aggregation of α-synuclein (α-syn) is the main pathologic event in Parkinson's disease (PD), dementia with Lewy bodies, and multiple system atrophy. α-Syn-seeded fibril formation and its induced toxicity occupy a major role in PD pathogenesis. Thus, assessing compounds that inhibit this seeding process is considered a key towards the therapeutics of synucleinopathies. Using biophysical and biochemical techniques and seeding-dependent cell viability assays, we screened a total of nine natural compounds of alkaloid origin extracted from Chinese medicinal herbs. Of these compounds, synephrine, trigonelline, cytisine, harmine, koumine, peimisine, and hupehenine exhibited in vitro inhibition of α-syn-seeded fibril formation. Furthermore, using cell viability assays, six of these compounds inhibited α-syn-seeding-dependent toxicity. These six potent inhibitors of amyloid fibril formation and toxicity caused by the seeding process represent a promising therapeutic strategy for the treatment of PD and other synucleinopathies.


Assuntos
Alcaloides/farmacologia , Produtos Biológicos/farmacologia , alfa-Sinucleína/antagonistas & inibidores , Amiloide/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Corpos de Lewy/efeitos dos fármacos , Corpos de Lewy/metabolismo , Medicina Tradicional Chinesa/métodos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo
2.
Biofactors ; 47(4): 570-586, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33893674

RESUMO

Amyloidosis is a concept that implicates disorders and complications that are due to abnormal protein accumulation in different cells and tissues. Protein aggregation-associated diseases are classified according to the type of aggregates and deposition sites, such as neurodegenerative disorders and type 2 diabetes mellitus. Polyphenolic phytochemicals such as curcumin and its derivatives have anti-amyloid effects both in vitro and in animal models; however, the underlying mechanisms are not understood. In this review, we summarized possible mechanisms by which curcumin could interfere with self-assembly processes and reduce amyloid aggregation in amyloidosis. Furthermore, we discuss clinical trials in which curcumin is used as a therapeutic agent for the treatment of diseases linking to protein aggregates.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Amiloidose/prevenção & controle , Síndrome de Creutzfeldt-Jakob/tratamento farmacológico , Curcumina/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Doença de Huntington/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Amiloidose/genética , Amiloidose/metabolismo , Amiloidose/patologia , Ensaios Clínicos como Assunto , Síndrome de Creutzfeldt-Jakob/genética , Síndrome de Creutzfeldt-Jakob/metabolismo , Síndrome de Creutzfeldt-Jakob/patologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Humanos , Doença de Huntington/genética , Doença de Huntington/metabolismo , Doença de Huntington/patologia , Hipoglicemiantes/uso terapêutico , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Estresse Oxidativo , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Agregados Proteicos/efeitos dos fármacos , alfa-Sinucleína/antagonistas & inibidores , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Proteínas tau/antagonistas & inibidores , Proteínas tau/genética , Proteínas tau/metabolismo
3.
Bioorg Chem ; 108: 104655, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33548732

RESUMO

The elusive targets and the multifactorial etiology of Parkinson's disease (PD) have hampered the discovery of a potent drug for PD. Furthermore, the presently available medications provide only symptomatic relief and have failed to mitigate the pathogenesis associated with PD. Therefore, the current study was aimed to evaluate the prospective of swertiamarin (SW), a secoiridoid glycoside isolated from a traditional medicinal plant, Enicostemma littorale Blume to ameliorate the characteristic features of PD in Caenorhabditis elegans. SW (25 µM) administration decreased the α-synuclein (α-syn) deposition, inhibited apoptosis and increased dopamine level mediated through upregulating the expression of genes linked to ceramide synthesis, mitochondrial morphology and function regulation, fatty acid desaturase genes along with stress responsive MAPK (mitogen-activated protein kinase) pathway genes. The neuroprotective effect of SW was evident from the robust reduction of 6-hydroxydopamine (6-OHDA) induced dopaminergic neurodegeneration independent of dopamine transporter (dat-1). SW mediated translational regulation of MAPK pathway genes was observed through increase expression of SKN-1 and GST-4. Further, in-silico molecular docking analysis of SW with C. elegans MEK-1 showed a promising binding affinity affirming the in-vivo results. Overall, these novel finding supports that SW is a possible lead for drug development against the multi- factorial PD pathologies.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Ligação a DNA/metabolismo , Gentianaceae/química , Glucosídeos Iridoides/farmacologia , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson/tratamento farmacológico , Pironas/farmacologia , Fatores de Transcrição/metabolismo , alfa-Sinucleína/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Caenorhabditis elegans/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Glucosídeos Iridoides/química , Glucosídeos Iridoides/isolamento & purificação , Estrutura Molecular , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Doença de Parkinson/metabolismo , Pironas/química , Pironas/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
4.
J Neurochem ; 156(6): 880-896, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32869336

RESUMO

A major pathological feature of Parkinson's disease (PD) is the aberrant accumulation of misfolded assemblies of alpha-synuclein (α-Syn). Protein clearance appears as a regulator of the 'α-Syn burden' underlying PD pathogenesis. The picture emerging is that a combination of pathways with complementary roles, including the Proteasome System and the Autophagy-Lysosome Pathway, contributes to the intracellular degradation of α-Syn. This study addresses the mechanisms governing the degradation of α-Syn species seeded by exogenous fibrils in neuronally differentiated SH-SY5Y neuroblastoma cells with inducible expression of α-Syn. Using human α-Syn recombinant fibrils (pre-formed fibrils, PFFs), seeding and aggregation of endogenous Proteinase K (PK)-resistant α-Syn species occurs within a time frame of 6 days, and is still prominent after 12 days of PFF addition. Clearance of α-Syn assemblies in this inducible model was enhanced after switching off α-Syn expression with doxycycline. Lysosomal inhibition led to accumulation of SDS-soluble α-Syn aggregates 6 days after PFF-addition or when switching off α-Syn expression. Additionally, the autophagic enhancer, rapamycin, induced the clearance of α-Syn aggregates 13 days post-PFF addition, indicating that autophagy is the major pathway for aggregated α-Syn clearance. SDS-soluble phosphorylated α-Syn at S129 was only apparent at 7 days of incubation with a higher amount of PFFs. Proteasomal inhibition resulted in further accumulation of SDS-soluble phosphorylated α-Syn at S129, with limited PK resistance. Our data suggest that in this inducible model autophagy is mainly responsible for the degradation of fibrillar α-Syn, whereas the proteasome system is responsible, at least in part, for the selective clearance of phosphorylated α-Syn oligomers.


Assuntos
Lisossomos/metabolismo , Neurônios/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Autofagia , Linhagem Celular , Sobrevivência Celular , Doxiciclina/farmacologia , Humanos , Imuno-Histoquímica , Lisossomos/efeitos dos fármacos , Fosforilação , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , alfa-Sinucleína/antagonistas & inibidores
5.
BMC Complement Med Ther ; 20(1): 73, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32143619

RESUMO

BACKGROUND: Recent studies indicated that seeded fibril formation and toxicity of α-synuclein (α-syn) play a main role in the pathogenesis of certain diseases including Parkinson's disease (PD), multiple system atrophy, and dementia with Lewy bodies. Therefore, examination of compounds that abolish the process of seeding is considered a key step towards therapy of several synucleinopathies. METHODS: Using biophysical, biochemical and cell-culture-based assays, assessment of eleven compounds, extracted from Chinese medicinal herbs, was performed in this study for their effect on α-syn fibril formation and toxicity caused by the seeding process. RESULTS: Salvianolic acid B and dihydromyricetin were the two compounds that strongly inhibited the fibril growth and neurotoxicity of α-syn. In an in-vitro cell model, these compounds decreased the insoluble phosphorylated α-syn and aggregation. Also, in primary neuronal cells, these compounds showed a reduction in α-syn aggregates. Both compounds inhibited the seeded fibril growth with dihydromyricetin having the ability to disaggregate preformed α-syn fibrils. In order to investigate the inhibitory mechanisms of these two compounds towards fibril formation, we demonstrated that salvianolic acid B binds predominantly to monomers, while dihydromyricetin binds to oligomeric species and to a lower extent to monomers. Remarkably, these two compounds stabilized the soluble non-toxic oligomers lacking ß-sheet content after subjecting them to proteinase K digestion. CONCLUSIONS: Eleven compounds were tested but only two showed inhibition of α-syn aggregation, seeded fibril formation and toxicity in vitro. These findings highlight an essential beginning for development of new molecules in the field of synucleinopathies treatment.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/toxicidade , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , alfa-Sinucleína/antagonistas & inibidores , Animais , Benzofuranos/farmacologia , Benzofuranos/toxicidade , Flavonóis/farmacologia , Flavonóis/toxicidade , Células HEK293 , Humanos , Camundongos , Estrutura Molecular , Agregação Patológica de Proteínas , Sinucleinopatias/tratamento farmacológico
6.
ACS Nano ; 14(2): 1533-1549, 2020 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-32027482

RESUMO

Although emerging evidence suggests that the pathogenesis of Parkinson's disease (PD) is closely related to the aggregation of alpha-synuclein (α-syn) in the midbrain, the clearance of α-syn remains an unmet clinical need. Here, we develop a simple and efficient strategy for fabricating the α-syn nanoscavenger for PD via a reprecipitation self-assembly procedure. The curcumin analogue-based nanoscavenger (NanoCA) is engineered to be capable of a controlled-release property to stimulate nuclear translocation of the major autophagy regulator, transcription factor EB (TFEB), triggering both autophagy and calcium-dependent exosome secretion for the clearance of α-syn. Pretreatment of NanoCA protects cell lines and primary neurons from MPP+-induced neurotoxicity. More importantly, a rapid arousal intranasal delivery system (RA-IDDS) was designed and applied for the brain-targeted delivery of NanoCA, which affords robust neuroprotection against behavioral deficits and promotes clearance of monomer, oligomer, and aggregates of α-syn in the midbrain of an MPTP mouse model of PD. Our findings provide a clinically translatable therapeutic strategy aimed at neuroprotection and disease modification in PD.


Assuntos
Curcumina/uso terapêutico , Nanoestruturas/química , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/tratamento farmacológico , alfa-Sinucleína/antagonistas & inibidores , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Curcumina/síntese química , Curcumina/química , Liberação Controlada de Fármacos , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Células PC12 , Doença de Parkinson/patologia , Tamanho da Partícula , Agregados Proteicos/efeitos dos fármacos , Ratos , Propriedades de Superfície , alfa-Sinucleína/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-31669661

RESUMO

Betula utilis (BU), an important medicinal plant that grows in high altitudes of the Himalayan region, has been utilized traditionally due to it's antibacterial, hepatoprotective, and anti-tumor properties. Here, we demonstrated the longevity and amyloid-ß toxicity attenuating activity of B. utilis ethanolic extract (BUE) in Caenorhabditis elegans. Lifespan of the worms was observed under both the standard laboratory and stress (oxidative and thermal) conditions. Effect of BUE was also observed on the attenuation of age-dependent physiological parameters. Further, gene-specific mutants and green fluorescent protein (GFP)-tagged strains were used to investigate the molecular mechanism underlying the beneficial effects mediated by BUE supplementation. Our results showed that BUE (50 µg/ml) extended the mean lifespan of C. elegans by 35.99% and increased its survival under stress conditions. The BUE also reduced the levels of intracellular reactive oxygen species (ROS) by 22.47%. A delayed amyloid-ß induced paralyses was observed in CL4176 transgenic worms. Interestingly, the BUE supplementation was also able to reduce the α-synuclein aggregation in NL5901 transgenic strain. Gene-specific mutant studies suggested that the BUE-mediated lifespan extension was dependent on daf-16, hsf-1, and skn-1 but not on sir-2.1 gene. Furthermore, transgenic reporter gene expression assay showed that BUE treatment enhanced the expression of stress-protective genes such as sod-3 and gst-4. Present findings suggested that ROS scavenging activity, together with multiple longevity mechanisms, were involved in BUE-mediated lifespan extension. Thus, BUE might have potential to increase the lifespan and to attenuate neuro-related disease progression.


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Antioxidantes/farmacologia , Betula/química , Caenorhabditis elegans/efeitos dos fármacos , Longevidade , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , alfa-Sinucleína/antagonistas & inibidores , Peptídeos beta-Amiloides/toxicidade , Animais , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/metabolismo , alfa-Sinucleína/metabolismo
8.
Eur J Pharmacol ; 862: 172635, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31491404

RESUMO

α-synucleopathies are protein-misfolding disorders occur primarily due to aggregation and toxicity of α-synuclein. This study characterized the small molecule AGK2 as a modifier of α-synuclein mediated toxicity in an autophagy dependent manner in both yeast and mammalian cell line models. In yeast system, AGK2 enhances autophagy to clear toxic α-synuclein aggregates in an autophagy dependent manner. Autophagy flux analyses revealed that AGK2 induces autophagy especially autolysosomes. Importantly, AGK2 induces autophagy in an mTOR independent manner. These features enable AGK2 to exert cytoprotective potential against α-synuclein mediated toxicity in different model systems.


Assuntos
Autofagia/efeitos dos fármacos , Furanos/farmacologia , Agregação Patológica de Proteínas/tratamento farmacológico , Quinolinas/farmacologia , Sinucleinopatias/tratamento farmacológico , alfa-Sinucleína/antagonistas & inibidores , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Citoproteção/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Células HeLa , Humanos , Agregação Patológica de Proteínas/patologia , Saccharomyces cerevisiae , Sinucleinopatias/patologia , alfa-Sinucleína/metabolismo
9.
Neurobiol Aging ; 82: 60-68, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31404721

RESUMO

Parkinson's disease (PD) is a common neurodegenerative disorder involving α-synuclein (α-syn) aggregation, oxidative stress, dysregulation of redox metal homeostasis, and neurotoxicity. Different phenolic compounds with known antioxidant or antichelating properties have been shown to also interfere with aggregation of amyloid proteins and modulate intracellular signaling pathways. The present study aims to investigate for the first time the effect of tyrosol (TYR), a simple phenol present in extra-virgin olive oil, on α-syn aggregation in a Caenorhabditis elegans model of PD and evaluate its potential to prevent α-syn toxicity, neurodegeneration, and oxidative stress in this model organism. Our results show that TYR is effective in reducing α-syn inclusions, resulting in a lower toxicity and extended life span of treated nematodes. Moreover, TYR delayed α-syn-dependent degeneration of dopaminergic neurons in vivo. TYR treatment also reduced reactive oxygen species level and promoted the expression of specific chaperones and antioxidant enzymes. Overall, our study puts into perspective TYR potential to be considered as nutraceutical that targets pivotal causal factors in PD.


Assuntos
Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos/métodos , Azeite de Oliva/administração & dosagem , Transtornos Parkinsonianos/dietoterapia , Transtornos Parkinsonianos/patologia , Álcool Feniletílico/análogos & derivados , Animais , Animais Geneticamente Modificados , Antioxidantes/administração & dosagem , Caenorhabditis elegans , Suplementos Nutricionais , Degeneração Neural/dietoterapia , Degeneração Neural/metabolismo , Degeneração Neural/patologia , Transtornos Parkinsonianos/metabolismo , Álcool Feniletílico/administração & dosagem , alfa-Sinucleína/antagonistas & inibidores , alfa-Sinucleína/metabolismo
10.
Methods Mol Biol ; 1948: 145-156, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30771176

RESUMO

The budding yeast Saccharomyces cerevisiae (S. cerevisiae) has been a remarkable experimental model for the discovery of fundamental biological processes. The high degree of conservation of cellular and molecular processes between the budding yeast and higher eukaryotes has made it a valuable system for the investigation of the molecular mechanisms behind various types of devastating human pathologies. Genetic screens in yeast provided important insight into the toxic mechanisms associated with the accumulation of misfolded proteins. Thus, using yeast genetics and high-throughput screens, novel molecular targets with therapeutic potential have been identified. Here, we describe a yeast screen protocol for the identification of genetic modifiers of alpha-synuclein (aSyn) toxicity, thereby accelerating the identification of novel potential targets for intervention in Parkinson's disease (PD) and other synucleinopathies.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Ensaios de Triagem em Larga Escala , Leveduras/genética , alfa-Sinucleína/antagonistas & inibidores , alfa-Sinucleína/genética , Humanos , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Reprodutibilidade dos Testes , Leveduras/metabolismo , alfa-Sinucleína/metabolismo
11.
Molecules ; 23(6)2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-29843466

RESUMO

Tea is one of the most consumed beverages in the world. Green tea, black tea, and oolong tea are made from the same plant Camellia sinensis (L.) O. Kuntze. Among them, green tea has been the most extensively studied for beneficial effects on diseases including cancer, obesity, diabetes, and inflammatory and neurodegenerative diseases. Several human observational and intervention studies have found beneficial effects of tea consumption on neurodegenerative impairment, such as cognitive dysfunction and memory loss. These studies supported the basis of tea's preventive effects of Parkinson's disease, but few studies have revealed such effects on Alzheimer's disease. In contrast, several human studies have not reported these favorable effects with regard to tea. This discrepancy may be due to incomplete adjustment of confounding factors, including the method of quantifying consumption, beverage temperature, cigarette smoking, alcohol consumption, and differences in genetic and environmental factors, such as race, sex, age, and lifestyle. Thus, more rigorous human studies are required to understand the neuroprotective effect of tea. A number of laboratory experiments demonstrated the benefits of green tea and green tea catechins (GTCs), such as epigallocatechin gallate (EGCG), and proposed action mechanisms. The targets of GTCs include the abnormal accumulation of fibrous proteins, such as Aß and α-synuclein, inflammation, elevated expression of pro-apoptotic proteins, and oxidative stress, which are associated with neuronal cell dysfunction and death in the cerebral cortex. Computational molecular docking analysis revealed how EGCG can prevent the accumulation of fibrous proteins. These findings suggest that GTCs have the potential to be used in the prevention and treatment of neurodegenerative diseases and could be useful for the development of new drugs.


Assuntos
Doença de Alzheimer/prevenção & controle , Catequina/análogos & derivados , Catequina/farmacologia , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson/prevenção & controle , Chá/química , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/química , Camellia sinensis/química , Catequina/química , Catequina/isolamento & purificação , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Humanos , Simulação de Acoplamento Molecular , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Estresse Oxidativo/efeitos dos fármacos , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , alfa-Sinucleína/antagonistas & inibidores , alfa-Sinucleína/química
12.
Sci Rep ; 7(1): 11469, 2017 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-28904388

RESUMO

α-synuclein-induced neurotoxicity is a core pathogenic event in neurodegenerative synucleinopathies such as Parkinson's disease, dementia with Lewy bodies, or multiple system atrophy. There is currently no disease-modifying therapy available for these diseases. We screened 1,600 FDA-approved drugs for their efficacy to protect LUHMES cells from degeneration induced by wild-type α-synuclein and identified dipyridamole, a non-selective phosphodiesterase inhibitor, as top hit. Systematic analysis of other phosphodiesterase inhibitors identified a specific phosphodiesterase 1 inhibitor as most potent to rescue from α-synuclein toxicity. Protection was mediated by an increase of cGMP and associated with the reduction of a specific α-synuclein oligomeric species. RNA interference experiments confirmed PDE1A and to a smaller extent PDE1C as molecular targets accounting for the protective efficacy. PDE1 inhibition also rescued dopaminergic neurons from wild-type α-synuclein induced degeneration in the substantia nigra of mice. In conclusion, this work identifies inhibition of PDE1A in particular as promising target for neuroprotective treatment of synucleinopathies.


Assuntos
Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Fosfodiesterase I/antagonistas & inibidores , Agregação Patológica de Proteínas/metabolismo , alfa-Sinucleína/metabolismo , Animais , Linhagem Celular , Dipiridamol/farmacologia , Avaliação Pré-Clínica de Medicamentos , Ensaios de Triagem em Larga Escala , Humanos , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Agregação Patológica de Proteínas/tratamento farmacológico , Alcaloides de Vinca/farmacologia , alfa-Sinucleína/antagonistas & inibidores
13.
ACS Chem Neurosci ; 8(11): 2356-2368, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28862431

RESUMO

Among the diseases affecting the central nervous system (CNS), neurodegenerations attract the interest of both the clinician and the medicinal chemist. The increasing average age of population, the growing number of patients, and the lack of long-term effective remedies push ahead the quest for novel tools against this class of pathologies. We present a review on the state of the art of the molecules (or combination of molecules) of natural origin that are currently under study against two well-defined pathologies: Parkinson's disease (PD) and Huntington's disease (HD). Nowadays, very few tools are available for preventing or counteracting the progression of such diseases. Two major parameters were considered for the preparation of this review: particular attention was reserved to these research works presenting well-defined molecular mechanisms for the studied compounds, and where available, papers reporting in vivo data were preferred. A literature search for peer-reviewed articles using PubMed, Scopus, and Reaxys databases was performed, exploiting different keywords and logical operators: 91 papers were considered (preferentially published after 2015). The review presents a brief overview on the etiology of the studied neurodegenerations and the current treatments, followed by a detailed discussion of the natural and semisynthetic compounds dividing them in different paragraphs considering their several mechanisms of action.


Assuntos
Antidiscinéticos/química , Produtos Biológicos/química , Doença de Huntington/tratamento farmacológico , Doença de Parkinson/tratamento farmacológico , Animais , Antidiscinéticos/síntese química , Antidiscinéticos/economia , Antidiscinéticos/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Antiparkinsonianos/síntese química , Antiparkinsonianos/química , Antiparkinsonianos/economia , Antiparkinsonianos/uso terapêutico , Autofagia/efeitos dos fármacos , Produtos Biológicos/economia , Produtos Biológicos/uso terapêutico , Demência/tratamento farmacológico , Demência/economia , Demência/epidemiologia , Dopamina/metabolismo , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Humanos , Doença de Huntington/economia , Doença de Huntington/epidemiologia , Doença de Huntington/fisiopatologia , Microglia/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Terapia de Alvo Molecular , Inibidores da Monoaminoxidase/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Doença de Parkinson/economia , Doença de Parkinson/epidemiologia , Doença de Parkinson/fisiopatologia , Preparações de Plantas/farmacologia , Preparações de Plantas/uso terapêutico , Agregação Patológica de Proteínas/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , alfa-Sinucleína/antagonistas & inibidores
14.
Colloids Surf B Biointerfaces ; 155: 159-165, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28419945

RESUMO

The etiology of Parkinson's disease (PD) relates to α-synuclein, a small protein with the ability to aggregate and form Lewy bodies. One of its prevention strategies is inhibition of α-synuclein oligomerization. We have investigated the interaction of α-synuclein and human serum albumin with 3,6-bis-О-di-О-galloyl-1,2,4-tri-О-galloyl-ß-d-glucose (a tannin isolated from the plant Rhus typhina). Using fluorescence spectroscopy method we found that this tannin interacts strongly with α-synuclein forming complexes. Circular dichroism analysis showed a time-dependent inhibition of α-synuclein aggregation in the presence of the tannin. On the other hand, 3,6-bis-О-di-О-galloyl-1,2,4-tri-О-galloyl-ß-d-glucose had a much stronger interaction with human serum albumin than α-synuclein. The calculated binding constant for tannin-protein interaction was considerably higher for albumin than α-synuclein. This tannin interacted with albumin through a "sphere of action" mechanism. The results lead to the conclusion that 3,6-bis-О-di-О-galloyl-1,2,4-tri-О-galloyl-ß-d-glucose is a potent preventive compound against Parkinson's disease. However, this tannin interacts very strongly with human serum albumin, significantly reducing the bioavailability of this compound.


Assuntos
Antiparkinsonianos/química , Rhus/química , Albumina Sérica/química , Taninos/química , alfa-Sinucleína/química , Antiparkinsonianos/isolamento & purificação , Humanos , Cinética , Extratos Vegetais/química , Agregados Proteicos , Ligação Proteica , Albumina Sérica/antagonistas & inibidores , Taninos/isolamento & purificação , alfa-Sinucleína/antagonistas & inibidores
15.
Biochim Biophys Acta ; 1864(9): 1160-1169, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27353564

RESUMO

The presence of Lewy bodies and Lewy neurites is a major pathological hallmark of Parkinson's disease and is hypothesized to be linked to disease development, although this is not yet conclusive. Lewy bodies and Lewy neurites primarily consist of fibrillated α-Synuclein; yet, there is no treatment available targeting stabilization of α-Synuclein in its native state. The aim of the present study was to investigate the inhibitory activity of an ethanolic extract of Geum urbanum against α-Synuclein fibrillation and examine the structural changes of α-Synuclein in the presence of the extract. The anti-fibrillation and anti-aggregation activities of the plant extract were monitored by thioflavin T fibrillation assays and size exclusion chromatography, while structural changes were followed by circular dichroism, Fourier transform infrared spectroscopy, intrinsic fluorescence, small angle X-ray scattering and electron microscopy. Since the extract is a complex mixture, structure-function relationships could not be determined. Under the experimental conditions investigated, Geum urbanum was found to inhibit α-Synuclein fibrillation in a concentration dependent way, and to partly disintegrate preformed α-Synuclein fibrils. Based on the structural changes of α-Synuclein in the presence of extract, we propose that Geum urbanum delays α-Synuclein fibrillation either by reducing the fibrillation ability of one or more of the aggregation prone intermediates or by directing α-Synuclein aggregation towards a non-fibrillar state. However, whether these alterations of the fibrillation pathway lead to less pathogenic species is yet to be determined.


Assuntos
Amiloide/química , Geum/química , Extratos Vegetais/química , Agregados Proteicos , alfa-Sinucleína/química , Amiloide/antagonistas & inibidores , Benzotiazóis , Humanos , Soluções , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Tiazóis , alfa-Sinucleína/antagonistas & inibidores
16.
Mar Drugs ; 13(4): 2250-66, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25874922

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disorder in the elderly people, currently with no cure. Its mechanisms are not well understood, thus studies targeting cause-directed therapy or prevention are needed. This study uses the transgenic Caenorhabditis elegans PD model. We demonstrated that dietary supplementation of the worms with an extract from the cultivated red seaweed Chondrus crispus decreased the accumulation of α-synulein and protected the worms from the neuronal toxin-, 6-OHDA, induced dopaminergic neurodegeneration. These effects were associated with a corrected slowness of movement. We also showed that the enhancement of oxidative stress tolerance and an up-regulation of the stress response genes, sod-3 and skn-1, may have served as the molecular mechanism for the C. crispus-extract-mediated protection against PD pathology. Altogether, apart from its potential as a functional food, the tested red seaweed, C. crispus, might find promising pharmaceutical applications for the development of potential novel anti-neurodegenerative drugs for humans.


Assuntos
Chondrus/química , Suplementos Nutricionais , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/dietoterapia , Extratos Vegetais/uso terapêutico , Alga Marinha/química , alfa-Sinucleína/antagonistas & inibidores , Animais , Animais Geneticamente Modificados , Aquicultura , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Comportamento Animal/efeitos dos fármacos , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/agonistas , Proteínas de Caenorhabditis elegans/antagonistas & inibidores , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Chondrus/crescimento & desenvolvimento , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Humanos , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microscopia de Fluorescência , Movimento/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Neurotoxinas/antagonistas & inibidores , Neurotoxinas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Extratos Vegetais/administração & dosagem , Proteínas Recombinantes de Fusão/metabolismo , Alga Marinha/crescimento & desenvolvimento , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
17.
Eur J Med Chem ; 88: 42-54, 2014 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-25081642

RESUMO

A major feature of Parkinson's disease is the formation of Lewy bodies in dopaminergic neurons which consist of misfolded α-synuclein. The binding of natural products to α-synuclein was evaluated by nanopore analysis and caffeine, curcumin, and nicotine all caused large conformational changes which may be related to their known neuroprotective effect in Parkinson's disease. The binding of the stereoisomers of nicotine were also studied by ITC, CD and NMR. It is proposed that (-)-nicotine causes the folding of α-synuclein into a loop with interaction between the N- and C-termini. For (+)-nicotine the binding is weaker and mainly involves residues in the N-terminus. Caffeine and nicotine can bind to α-synuclein simultaneously and may provide lead structures for the development of other compounds for the treatment of PD.


Assuntos
Produtos Biológicos/metabolismo , Descoberta de Drogas/métodos , Nanoporos , Doença de Parkinson/tratamento farmacológico , alfa-Sinucleína/metabolismo , Sítios de Ligação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/uso terapêutico , Cafeína/química , Cafeína/metabolismo , Calorimetria , Humanos , Conformação Molecular , Nicotina/análogos & derivados , Nicotina/química , Nicotina/metabolismo , Ressonância Magnética Nuclear Biomolecular , Dobramento de Proteína , Relação Estrutura-Atividade , alfa-Sinucleína/antagonistas & inibidores
18.
PLoS One ; 9(1): e85305, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24416384

RESUMO

BACKGROUND: Parkinson's disease (PD) is the second most common degenerative disorder of the central nervous system that impairs motor skills and cognitive function. To date, the disease has no effective therapies. The identification of new drugs that provide benefit in arresting the decline seen in PD patients is the focus of much recent study. However, the lengthy time frame for the progression of neurodegeneration in PD increases both the time and cost of examining potential therapeutic compounds in mammalian models. An alternative is to first evaluate the efficacy of compounds in Caenorhabditis elegans models, which reduces examination time from months to days. n-Butylidenephthalide is the naturally-occurring component derived from the chloroform extract of Angelica sinensis. It has been shown to have anti-tumor and anti-inflammatory properties, but no reports have yet described the effects of n-butylidenephthalide on PD. The aim of this study was to assess the potential for n-butylidenephthalide to improve PD in C. elegans models. METHODOLOGY/PRINCIPAL FINDINGS: In the current study, we employed a pharmacological strain that expresses green fluorescent protein specifically in dopaminergic neurons (BZ555) and a transgenic strain that expresses human α-synuclein in muscle cells (OW13) to investigate the antiparkinsonian activities of n-butylidenephthalide. Our results demonstrate that in PD animal models, n-butylidenephthalide significantly attenuates dopaminergic neuron degeneration induced by 6-hydroxydopamine; reduces α-synuclein accumulation; recovers lipid content, food-sensing behavior, and dopamine levels; and prolongs life-span of 6-hydroxydopamine treatment, thus revealing its potential as a possible antiparkinsonian drug. n-Butylidenephthalide may exert its effects by blocking egl-1 expression to inhibit apoptosis pathways and by raising rpn-6 expression to enhance the activity of proteasomes. CONCLUSIONS/SIGNIFICANCE: n-Butylidenephthalide may be one of the effective neuroprotective agents for PD.


Assuntos
Angelica sinensis/química , Antiparkinsonianos/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Neurônios Dopaminérgicos/efeitos dos fármacos , Anidridos Ftálicos/farmacologia , alfa-Sinucleína/antagonistas & inibidores , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/agonistas , Proteínas de Caenorhabditis elegans/antagonistas & inibidores , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Modelos Animais de Doenças , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Medicamentos de Ervas Chinesas/química , Regulação da Expressão Gênica , Humanos , Longevidade/efeitos dos fármacos , Células Musculares/efeitos dos fármacos , Células Musculares/metabolismo , Células Musculares/patologia , Oxidopamina/farmacologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transgenes , alfa-Sinucleína/biossíntese , alfa-Sinucleína/genética
19.
Free Radic Biol Med ; 67: 58-68, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24148766

RESUMO

Parkinson disease (PD) is a multifactorial disease resulting in preferential death of the dopaminergic neurons in the substantia nigra. Studies of PD-linked genes and toxin-induced models of PD have implicated mitochondrial dysfunction, oxidative stress, and the misfolding and aggregation of α-synuclein (α-syn) as key factors in disease initiation and progression. Many of these features of PD may be modeled in cells or animal models using the neurotoxin 1-methyl-4-phenylpyridinium (MPP(+)). Reducing oxidative stress and nitric oxide synthase (NOS) activity has been shown to be protective in cell or animal models of MPP(+) toxicity. We have previously demonstrated that siRNA-mediated knockdown of α-syn lowers the activity of both dopamine transporter and NOS activity and protects dopaminergic neuron-like cells from MPP(+) toxicity. Here, we demonstrate that α-syn knockdown and modulators of oxidative stress/NOS activation protect cells from MPP(+)-induced toxicity via postmitochondrial mechanisms rather than by a rescue of the decrease in mitochondrial oxidative phosphorylation caused by MPP(+) exposure. We demonstrate that MPP(+) significantly decreases the synthesis of the antioxidant and obligate cofactor of NOS and TH tetrahydrobiopterin (BH4) through decreased cellular GTP/ATP levels. Furthermore, we demonstrate that RNAi knockdown of α-syn results in a nearly twofold increase in GTP cyclohydrolase I activity and a concomitant increase in basal BH4 levels. Together, these results demonstrate that both mitochondrial activity and α-syn play roles in modulating cellular BH4 levels.


Assuntos
Biopterinas/análogos & derivados , Neurônios Dopaminérgicos/metabolismo , Mitocôndrias/metabolismo , alfa-Sinucleína/genética , 1-Metil-4-fenilpiridínio/toxicidade , Trifosfato de Adenosina/metabolismo , Biopterinas/metabolismo , Linhagem Celular Tumoral , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , GTP Cicloidrolase/genética , GTP Cicloidrolase/metabolismo , Regulação da Expressão Gênica , Guanosina Trifosfato/metabolismo , Humanos , Mitocôndrias/efeitos dos fármacos , Modelos Biológicos , Fosforilação Oxidativa , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , alfa-Sinucleína/antagonistas & inibidores , alfa-Sinucleína/metabolismo
20.
Brain Res ; 1508: 53-62, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23499562

RESUMO

The 3-O-demethylswertipunicoside (3-ODS) is extracted from Swertia punicea. Recent study from our laboratory has demonstrated that the 3-ODS protects against oxidative toxicity and apoptosis in PC12 cells (Zhang, S.P., Du, X.G., Pu, X.P., 2010. Biol. Pharm. Bull. 33, 1529-1533). The aim of our study is to further investigate the neuroprotective mechanisms of 3-ODS in 1-methyl-4-phenylpyridinium (MPP(+))-induced neurotoxicity in PC12 cells. The results indicated that pre-treatment with 3-ODS significantly increased the cell viability compared with MPP(+) treatment. It also alleviated the oxidative stress by increasing superoxide dismutase (SOD) activity and decreasing malondialdehyde (MDA) level and reactive oxygen specise (ROS) production. Moreover, 3-ODS also attenuated MPP(+)-induced apoptosis by inhibiting Bax and Bcl-2 expressions, activating caspase-9, caspase-3, poly (ADP-ribose) polymerase-1 (PARP-1) cleavage, apoptosis-inducing factor (AIF) translocation and α-synuclein expression. These results suggest that 3-ODS might has applications as a complementary medicine for the treatment of Parkinson's disease (PD) or other neurodegenerative diseases.


Assuntos
1-Metil-4-fenilpiridínio/antagonistas & inibidores , 1-Metil-4-fenilpiridínio/toxicidade , Apoptose/efeitos dos fármacos , Dopaminérgicos/toxicidade , Glucosídeos/farmacologia , Fármacos Neuroprotetores , Estresse Oxidativo/efeitos dos fármacos , Xantonas/farmacologia , Animais , Fator de Indução de Apoptose/metabolismo , Western Blotting , Malondialdeído/metabolismo , Mitocôndrias/efeitos dos fármacos , Células PC12 , Transporte Proteico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Espécies Reativas de Oxigênio , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo , alfa-Sinucleína/antagonistas & inibidores , alfa-Sinucleína/biossíntese , Proteína X Associada a bcl-2/metabolismo
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