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1.
Br J Nutr ; 115(3): 449-65, 2016 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-26652155

RESUMO

Curcumin derived from turmeric is well documented for its anti-carcinogenic, antioxidant and anti-inflammatory properties. Recent studies show that curcumin also possesses neuroprotective and cognitive-enhancing properties that may help delay or prevent neurodegenerative diseases, including Alzheimer's disease (AD). Currently, clinical diagnosis of AD is onerous, and it is primarily based on the exclusion of other causes of dementia. In addition, phase III clinical trials of potential treatments have mostly failed, leaving disease-modifying interventions elusive. AD can be characterised neuropathologically by the deposition of extracellular ß amyloid (Aß) plaques and intracellular accumulation of tau-containing neurofibrillary tangles. Disruptions in Aß metabolism/clearance contribute to AD pathogenesis. In vitro studies have shown that Aß metabolism is altered by curcumin, and animal studies report that curcumin may influence brain function and the development of dementia, because of its antioxidant and anti-inflammatory properties, as well as its ability to influence Aß metabolism. However, clinical studies of curcumin have revealed limited effects to date, most likely because of curcumin's relatively low solubility and bioavailability, and because of selection of cohorts with diagnosed AD, in whom there is already major neuropathology. However, the fresh approach of targeting early AD pathology (by treating healthy, pre-clinical and mild cognitive impairment-stage cohorts) combined with new curcumin formulations that increase bioavailability is renewing optimism concerning curcumin-based therapy. The aim of this paper is to review the current evidence supporting an association between curcumin and modulation of AD pathology, including in vitro and in vivo studies. We also review the use of curcumin in emerging retinal imaging technology, as a fluorochrome for AD diagnostics.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/prevenção & controle , Curcumina/farmacologia , Animais , Cognição/efeitos dos fármacos , Modelos Animais de Doenças , Corantes Fluorescentes/análise , Humanos , Emaranhados Neurofibrilares/efeitos dos fármacos , Emaranhados Neurofibrilares/metabolismo , Fármacos Neuroprotetores/farmacologia , Nootrópicos/farmacologia , Ensaio Radioligante/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
IBRO Neurosci Rep ; 14: 264-272, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36926592

RESUMO

Melatonin is a hormone secreted by the pineal gland, it can be associated with circadian rhythms, aging and neuroprotection. Melatonin levels are decreased in sporadic Alzheimer's disease (sAD) patients, which suggests a relationship between the melatonergic system and sAD. Melatonin may reduce inflammation, oxidative stress, TAU protein hyperphosphorylation, and the formation of ß-amyloid (Aß) aggregates. Therefore, the objective of this work was to investigate the impact of treatment with 10 mg/kg of melatonin (i.p) in the animal model of sAD induced by the intracerebroventricular (ICV) infusion of 3 mg/kg of streptozotocin (STZ). ICV-STZ causes changes in the brain of rats similar to those found in patients with sAD. These changes include; progressive memory decline, the formation of neurofibrillary tangles, senile plaques, disturbances in glucose metabolism, insulin resistance and even reactive astrogliosis characterized by the upregulation of glucose levels and glial fibrillary acidic protein (GFAP). The results show that ICV-STZ caused short-term spatial memory impairment in rats after 30 days of STZ infusion without locomotor impairment which was evaluated on day 27 post-injury. Furthermore, we observed that a prolonged 30-day treatment with melatonin can improve the cognitive impairment of animals in the Y-maze test, but not in the object location test. Finally, we demonstrated that animals receiving ICV-STZ have high levels of Aß and GFAP in the hippocampus and that treatment with melatonin reduces Aß levels but does not reduce GFAP levels, concluding that melatonin may be useful to control the progression of amyloid pathology in the brain.

3.
J Biochem ; 174(5): 409-420, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37488092

RESUMO

Amyloid-ß (Aß) accumulation caused by an imbalance of the production and clearance of Aß in the brain is associated with the development of Alzheimer's disease (ad). Apolipoprotein E (ApoE) (the strongest genetic risk factor) enhances Aß clearance, preventing Aß deposition. Sirtuin 2 (Sirt2) is an NAD+-dependent histone deacetylase and its inhibition has been reported to ameliorate memory impairment in ad-like model mice. However, the role of Sirt2 in ApoE secretion is unknown. Here, we found that inhibition of Sirt2 activity in primary cultured astrocytes and BV2 cells decreased ApoE secretion, resulting in the accumulation of intracellular ApoE and inhibiting extracellular Aß degradation. However, the reduction of Sirt2 protein level by Sirt2 siRNA decreased ApoE protein level, which ultimately reduces ApoE secretion. In addition, the knockdown of Sirt2 in the HEK293-APP cells also decreased levels of intracellular ApoE leading to reduction of its secretion, which is accompanied by increased Aß levels without altering APP and APP processing enzymes. Our findings provide a novel role of Sirt2 in ApoE secretion.


Assuntos
Doença de Alzheimer , Sirtuína 2 , Animais , Humanos , Camundongos , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Astrócitos , Encéfalo/metabolismo , Células HEK293 , Camundongos Transgênicos , Microglia/metabolismo , Sirtuína 2/metabolismo
4.
Front Cell Neurosci ; 16: 846459, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35614968

RESUMO

The amyloid precursor protein (APP) processing pathway was altered in Alzheimer's disease (AD) and contributed to abnormal amyloid-beta (Aß) production, which forms insoluble interneuron protein aggregates known as amyloid plaques in the brain. Targeting the APP processing pathway is still fundamental for AD modifying therapy. Extensive research has evaluated the protective effects of vitamin E as an antioxidant and as a signaling molecule. The present study aimed to investigate the modulatory effects of different tocopherol isomers on the expression of genes involved in regulating the APP processing pathway in vitro. The screening for the effective tocopherol isomers in reducing APP expression and Aß-42 was carried out in SH-SY5Y stably overexpressed APP Swedish. Subsequently, quantitative one-step real-time PCR was performed to determine the modulatory effects of selected tocopherol isomers on the expression of genes in SH-SY5Y stably overexpressed three different types of APP (wild-type, APP Swedish, and APP Swedish/Indiana). Our results showed that all tocopherol isomers, especially at higher concentrations (80-100 µM), significantly increased (p < 0.05) the cell viability in all cells group, but only α-tocopherol (ATF) and γ-tocopherol (GTF) significantly decreased (p < 0.05) the APP mRNA level without statistically significant APP protein level, accompanied with a reduced significance (p < 0.05) on the level of Aß-42 in SH-SY5Y APP Swedish. On the other hand, ß- and δ-tocopherol (BTF and DTF) showed no effects on the level of APP expression and Aß-42. Subsequent results demonstrated that ATF and GTF significantly decreased (p < 0.05) the expression of gene beta-site APP cleaving enzyme (BACE1), APH1B, and Nicastrin (NCSTN), but significantly increased (p < 0.05) the expression of Sirtuin 1 (SIRT1) in SH-SY5Y stably expressed the mutant APP form. These findings suggested that ATF and GTF could modulate altered pathways and may help ameliorate the burden of amyloid load in AD.

5.
IBRO Neurosci Rep ; 12: 131-141, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35146484

RESUMO

Lysosomal network abnormalities are an increasingly recognised feature of Alzheimer's disease (AD), which appear early and are progressive in nature. Sandhoff disease and Tay-Sachs disease (neurological lysosomal storage diseases caused by mutations in genes that code for critical subunits of ß-hexosaminidase) result in accumulation of amyloid-ß (Aß) and related proteolytic fragments in the brain. However, experiments that determine whether mutations in genes that code for ß-hexosaminidase are risk factors for AD are currently lacking. To determine the relationship between ß-hexosaminidase and AD, we investigated whether a heterozygous deletion of Hexb, the gene that encodes the beta subunit of ß-hexosaminidase, modifies the behavioural phenotype and appearance of disease lesions in App NL-G-F/NL-G-F (App KI/KI ) mice. App KI/KI and Hexb +/- mice were crossed and evaluated in a behavioural test battery. Neuropathological hallmarks of AD and ganglioside levels in the brain were also examined. Heterozygosity of Hexb in App KI/KI mice reduced learning flexibility during the Reversal Phase of the Morris water maze. Contrary to expectation, heterozygosity of Hexb caused a small but significant decrease in amyloid beta deposition and an increase in the microglial marker IBA1 that was region- and age-specific. Hexb heterozygosity caused detectable changes in the brain and in the behaviour of an AD model mouse, consistent with previous reports that described a biochemical relationship between HEXB and AD. This study reveals that the lysosomal enzyme gene Hexb is not haplosufficient in the mouse AD brain.

6.
J Adv Res ; 35: 231-243, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35024199

RESUMO

Introduction: Honokiol (HO) exerts neuroprotective effects in several animal models of Alzheimer's disease (AD), but the poor dissolution hampers its bioavailability and therapeutic efficacy. Objectives: A novel honokiol nanoscale drug delivery system (Nano-HO) with smaller size and excellent stability was developed in this study to improve the solubility and bioavailability of HO. The anti-AD effects of Nano-HO was determined. Methods: Male TgCRND8 mice were daily orally administered Nano-HO or HO at the same dosage (20 mg/kg) for 17 consecutive weeks, followed by assessment of the spatial learning and memory functions using the Morris Water Maze test (MWMT). Results: Our pharmacokinetic study indicated that the oral bioavailability was greatly improved by Nano-HO. In addition, Nano-HO significantly improved cognitive deficits and inhibited neuroinflammation via suppressing the levels of TNF-α, IL-6 and IL-1ß in the brain, preventing the activation of microglia (IBA-1) and astrocyte (GFAP), and reducing ß-amyloid (Aß) deposition in the cortex and hippocampus of TgCRND8 mice. Moreover, Nano-HO was more effective than HO in modulating amyloid precursor protein (APP) processing via suppressing ß-secretase, as well as enhancing Aß-degrading enzymes like neprilysin (NEP). Furthermore, Nano-HO more markedly inhibited tau hyperphosphorylation via decreasing the ratio of p-Tau (Thr 205)/tau and regulating tau-related apoptosis proteins (caspase-3 and Bcl-2). In addition, Nano-HO more markedly attenuated the ratios of p-JNK/JNK and p-35/CDK5, while enhancing the ratio of p-GSK-3ß (Ser9)/GSK-3ß. Finally, Nano-HO prevented the gut microflora dysbiosis in TgCRND8 mice in a more potent manner than free HO. Conclusion: Nano-HO was more potent than free HO in improving cognitive impairments in TgCRND8 mice via inhibiting Aß deposition, tau hyperphosphorylation and neuroinflammation through suppressing the activation of JNK/CDK5/GSK-3ß signaling pathway. Nano-HO also more potently modulated the gut microbiota community to protect its stability than free HO. These results suggest that Nano-HO has good potential for further development into therapeutic agent for AD treatment.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Microbioma Gastrointestinal , Doença de Alzheimer/tratamento farmacológico , Animais , Compostos de Bifenilo , Cognição , Disfunção Cognitiva/tratamento farmacológico , Glicogênio Sintase Quinase 3 beta , Lignanas , Masculino , Camundongos , Doenças Neuroinflamatórias
7.
Brain Behav Immun Health ; 21: 100435, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35252893

RESUMO

Despite the rise of Alzheimer's disease (AD) in an ageing population, no cure is currently available for this disorder. This study assessed the role of a natural compound, Antroquinonol, in modifying the progression of AD when administered at the start and/or before appearance of symptoms and when the disease was well established, in a transgenic animal model. Antroquinonol was administered daily for 8 weeks, in 11 week (early stage) and 9 month (late stage) male transgenic mice (3 times Transgenic mice PS1M146V, APPSwe, and tauP301L, 3 â€‹Tg XAD) and their respective aged controls. Behavioural testing (including Elevated Plus Maze Watermaze, Recognition object testing and Y maze) was performed at the end of the drug administration. In addition AD biomarkers (Amyloid beta 42 (Aß42), tau and phospho-tau levels), oxidative stress and inflammatory markers, were assessed in tested mice brains after their sacrifice at the end of the treatment. When administered before the start of symptoms at 11 weeks, Antroquinonol treatment at 34 â€‹mg/kg (D2) and more consistently at 75 â€‹mg/kg (D3), had a significant effect on reducing systemic inflammatory markers (Interleukin 1, IL-1ß and TNF-α) and AD biomarker (Amyloid Beta 42, Aß42 and tau) levels in the brain. The reduction of behavioural impairment reported for 3TgXAD mice was observed significantly for the D3 drug dose only and for all behavioural tests, when administered at 11 weeks. Similarly, beneficial effects of Antroquinonol (at higher dose D3) were noted in the transgenic mice in terms of AD biomarkers (tau and phosphorylated-tau), systemic inflammatory (IL-1ß), brain anti-inflammatory (Nrf2) and oxidative (3-Nitrotyrosine, 3NT) markers. Improvement of memory impairment was also reported when Antroquinonol (D3) was administered at late stage (9 months). Since Antroquinonol has been used without adverse effects in previous successful clinical trials, this drug may offer a new avenue of treatment to modify AD development and progression.

8.
J Adv Res ; 34: 1-12, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-35024177

RESUMO

Introduction: Alzheimer's disease (AD) is a progressive brain disorder, and one of the most common causes of dementia and amnesia. Due to the complex pathogenesis of AD, the underlying mechanisms remain unclear. Although scientists have made increasing efforts to develop drugs for AD, no effective therapeutic agents have been found. Objectives: Natural products and their constituents have shown promise for treating neurodegenerative diseases, including AD. Thus, in-depth study of medical plants, and the main active ingredients thereof against AD, is necessary to devise therapeutic agents. Methods: In this study, N2a/APP cells and SAMP8 mice were employed as in vitro and in vivo models of AD. Multiple molecular biological methods were used to investigate the potential therapeutic actions of oxyphylla A, and the underlying mechanisms. Results: Results showed that oxyphylla A, a novel compound extracted from Alpinia oxyphylla, could reduce the expression levels of amyloid precursor protein (APP) and amyloid beta (Aß) proteins, and attenuate cognitive decline in SAMP8 mice. Further investigation of the underlying mechanisms showed that oxyphylla A exerted an antioxidative effect through the Akt-GSK3ß and Nrf2-Keap1-HO-1 pathways.Conclusions.Taken together, our results suggest a new horizon for the discovery of therapeutic agents for AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Animais , Caproatos , Cognição , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Cresóis , Modelos Animais de Doenças , Glicogênio Sintase Quinase 3 beta , Proteína 1 Associada a ECH Semelhante a Kelch , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt
9.
Comput Struct Biotechnol J ; 19: 6490-6504, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34976306

RESUMO

The adenosine-triphosphate-(ATP)-binding cassette (ABC) transporter ABCA7 is a genetic risk factor for Alzheimer's disease (AD). Defective ABCA7 promotes AD development and/or progression. Unfortunately, ABCA7 belongs to the group of 'under-studied' ABC transporters that cannot be addressed by small-molecules. However, such small-molecules would allow for the exploration of ABCA7 as pharmacological target for the development of new AD diagnostics and therapeutics. Pan-ABC transporter modulators inherit the potential to explore under-studied ABC transporters as novel pharmacological targets by potentially binding to the proposed 'multitarget binding site'. Using the recently reported cryogenic-electron microscopy (cryo-EM) structures of ABCA1 and ABCA4, a homology model of ABCA7 has been generated. A set of novel, diverse, and potent pan-ABC transporter inhibitors has been docked to this ABCA7 homology model for the discovery of the multitarget binding site. Subsequently, application of pharmacophore modelling identified the essential pharmacophore features of these compounds that may support the rational drug design of innovative diagnostics and therapeutics against AD.

10.
J Ginseng Res ; 44(4): 538-543, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32617033

RESUMO

Cardiovascular diseases are a rapidly growing epidemic with high morbidity and mortality. There is an urgent need to develop nutraceutical-based therapy with minimum side effects to reduce cardiovascular risk. Panax ginseng occupies a prominent status in herbal medicine for its various therapeutic effects against inflammation, allergy, diabetes, cardiovascular diseases, and even cancer, with positive, beneficial, and restorative effects. The active components found in most P. ginseng varieties are known to include ginsenosides, polysaccharides, peptides, alkaloids, polyacetylene, and phenolic compounds, which are considered to be the main pharmacologically active constituents in ginseng. P. ginseng is an adaptogen. That is, it supports living organisms to maintain optimal homeostasis by exerting effects that counteract physiological changes caused by physical, chemical, or biological stressors. P. ginseng possesses immunomodulatory (including both immunostimulatory and immunosuppressive), neuromodulatory, and cardioprotective effects; suppresses anxiety; and balances vascular tone. P. ginseng has an antihypertensive effect that has been explained by its vasorelaxant action, and paradoxically, it is also known to increase blood pressure by vasoconstriction and help maintain cardiovascular health. Here, we discuss the potential adaptogenic effects of P. ginseng on the cardiovascular system and outline a future research perspective in this area.

11.
Acta Pharm Sin B ; 10(4): 646-666, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32322468

RESUMO

Drug repurposing is an efficient strategy for new drug discovery. Our latest study found that nitazoxanide (NTZ), an approved anti-parasite drug, was an autophagy activator and could alleviate the symptom of Alzheimer's disease (AD). In order to further improve the efficacy and discover new chemical entities, a series of NTZ-based derivatives were designed, synthesized, and evaluated as autophagy activator against AD. All compounds were screened by the inhibition of phosphorylation of p70S6K, which was the direct substrate of mammalian target of rapamycin (mTOR) and its phosphorylation level could reflect the mTOR-dependent autophagy level. Among these analogs, compound 22 exhibited excellent potency in promoting ß-amyloid (Aß) clearance, inhibiting tau phosphorylation, as well as stimulating autophagy both in vitro and in vivo. What's more, 22 could effectively improve the memory and cognitive impairments in APP/PS1 transgenic AD model mice. These results demonstrated that 22 was a potential candidate for the treatment of AD.

12.
Front Neuroinform ; 13: 75, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31849633

RESUMO

Transgenic animal models are invaluable research tools for elucidating the pathways and mechanisms involved in the development of neurodegenerative diseases. Mechanistic clues can be revealed by applying labelling techniques such as immunohistochemistry or in situ hybridisation to brain tissue sections. Precision in both assigning anatomical location to the sections and quantifying labelled features is crucial for output validity, with a stereological approach or image-based feature extraction typically used. However, both approaches are restricted by the need to manually delineate anatomical regions. To circumvent this limitation, we present the QUINT workflow for quantification and spatial analysis of labelling in series of rodent brain section images based on available 3D reference atlases. The workflow is semi-automated, combining three open source software that can be operated without scripting knowledge, making it accessible to most researchers. As an example, a brain region-specific quantification of amyloid plaques across whole transgenic Tg2576 mouse brain series, immunohistochemically labelled for three amyloid-related antigens is demonstrated. First, the whole brain image series were registered to the Allen Mouse Brain Atlas to produce customised atlas maps adapted to match the cutting plan and proportions of the sections (QuickNII software). Second, the labelling was segmented from the original images by the Random Forest Algorithm for supervised classification (ilastik software). Finally, the segmented images and atlas maps were used to generate plaque quantifications for each region in the reference atlas (Nutil software). The method yielded comparable results to manual delineations and to the output of a stereological method. While the use case demonstrates the QUINT workflow for quantification of amyloid plaques only, the workflow is suited to all mouse or rat brain series with labelling that is visually distinct from the background, for example for the quantification of cells or labelled proteins.

13.
Clin Mass Spectrom ; 14 Pt B: 83-88, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34917764

RESUMO

In the field of Alzheimer's disease, there is an urgent need for novel analytical tools to identify disease-specific biomarkers and to evaluate therapeutics. Preclinical trials commonly employ amyloid beta (Aß) peptide signatures as a read-out. In this paper, we report a simplified and detailed protocol for robust immunoprecipitation of Aß in brain tissue prior to mass spectrometric detection exemplified by a study using transgenic mice. The established method employed murine monoclonal and rabbit polyclonal antibodies and was capable of yielding well-reproducible peaks of high intensity with low background signal intensities corresponding to various Aß forms.

14.
Comput Struct Biotechnol J ; 17: 963-971, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31360335

RESUMO

Alzheimer's disease (AD) is a neurodegenerative process characterized by the accumulation of extracellular deposits of amyloid ß-peptide (Aß), which induces neuronal death. Monomeric Aß is not toxic but tends to aggregate into ß-sheets that are neurotoxic. Therefore to prevent or delay AD onset and progression one of the main therapeutic approaches would be to impair Aß assembly into oligomers and fibrils and to promote disaggregation of the preformed aggregate. Albumin is the most abundant protein in the cerebrospinal fluid and it was reported to bind Aß impeding its aggregation. In a previous work we identified a 35-residue sequence of clusterin, a well-known protein that binds Aß, that is highly similar to the C-terminus (CTerm) of albumin. In this work, the docking experiments show that the average binding free energy of the CTerm-Aß1-42 simulations was significantly lower than that of the clusterin-Aß1-42 binding, highlighting the possibility that the CTerm retains albumin's binding properties. To validate this observation, we performed in vitro structural analysis of soluble and aggregated 1 µM Aß1-42 incubated with 5 µM CTerm, equimolar to the albumin concentration in the CSF. Reversed-phase chromatography and electron microscopy analysis demonstrated a reduction of Aß1-42 aggregates when the CTerm was present. Furthermore, we treated a human neuroblastoma cell line with soluble and aggregated Aß1-42 incubated with CTerm obtaining a significant protection against Aß-induced neurotoxicity. These in silico and in vitro data suggest that the albumin CTerm is able to impair Aß aggregation and to promote disassemble of Aß aggregates protecting neurons.

15.
Heliyon ; 5(3): e01293, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30923761

RESUMO

Niemann-Pick type C disease (NPC) is a fatal autosomal recessive disorder characterized by a defect in the intracellular transport of lipoproteins leading to the accumulation of lipids in diverse tissues. A visceral and neuronal phenotype mimicking human NPC1 disease has been described in NPC1 mutant mice. These mice are by now the most widely used NPC1 rodent model to study NPC and developmental compounds against this devastating disease. Here we characterized NPC1-/- mice for their hepatic and neuronal phenotype to confirm the stability of the phenotype, provide a characterization of disease progression and pinpoint the age of robust phenotype onset. Animals of 4-10 weeks of age were analyzed for general health, motor deficits as well as hepatic and neuronal alterations with a special focus on cerebellar pathology. Our results show that NPC1-/- mice have a reduced general health at the age of 9-10 weeks. Robust motor deficits can be observed even earlier at 8 weeks of age. Hepatic changes included increased organ weight and cholesterol levels at 6 weeks of age accompanied by severely increased liver enzyme levels. Analysis of NPC1-/- brain pathology showed decreased cholesterol and increased Aß levels in the hippocampus at the age of 6 weeks. Further analysis revealed a decrease of the cytokine IL-12p70 in the cerebellum along with a very early increase of astrocytosis. Hippocampal IL-12p70 levels were increased at the age of 6 weeks followed by increased activated microglia levels. By the age of 10 weeks, also cerebellar Aß levels were increased along with strongly reduced Calbindin D-28k levels. Our results validate and summarize the progressive development of the hepatic and neuronal phenotype of NPC1-/- mice that starts with cerebellar astrocytosis, making this mouse model a valuable tool for the development of new compounds against NPC.

16.
J Biomol Struct Dyn ; 37(5): 1282-1306, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29578387

RESUMO

Alzheimer's disease (AD) is a multi-factorial disease, which can be simply outlined as an irreversible and progressive neurodegenerative disorder with an unclear root cause. It is a major cause of dementia in old aged people. In the present study, utilizing the structural and biological activity information of ligands for five important and mostly studied vital targets (i.e. cyclin-dependant kinase 5, ß-secretase, monoamine oxidase B, glycogen synthase kinase 3ß, acetylcholinesterase) that are believed to be effective against AD, we have developed five classification models using linear discriminant analysis (LDA) technique. Considering the importance of data curation, we have given more attention towards the chemical and biological data curation, which is a difficult task especially in case of big data-sets. Thus, to ease the curation process we have designed Konstanz Information Miner (KNIME) workflows, which are made available at http://teqip.jdvu.ac.in/QSAR_Tools/ . The developed models were appropriately validated based on the predictions for experiment derived data from test sets, as well as true external set compounds including known multi-target compounds. The domain of applicability for each classification model was checked based on a confidence estimation approach. Further, these validated models were employed for screening of natural compounds collected from the InterBioScreen natural database ( https://www.ibscreen.com/natural-compounds ). Further, the natural compounds that were categorized as 'actives' in at least two classification models out of five developed models were considered as multi-target leads, and these compounds were further screened using the drug-like filter, molecular docking technique and then thoroughly analyzed using molecular dynamics studies. Finally, the most potential multi-target natural compounds against AD are suggested.


Assuntos
Produtos Biológicos/química , Produtos Biológicos/farmacologia , Descoberta de Drogas , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Doença de Alzheimer/tratamento farmacológico , Biomarcadores , Bases de Dados Genéticas , Bases de Dados de Produtos Farmacêuticos , Desenho de Fármacos , Humanos , Ligantes , Curva ROC , Fluxo de Trabalho
17.
Tissue Cell ; 50: 89-95, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29429523

RESUMO

In middle and old age, Alzheimer's disease (AD) is a progressive neurodegenerative disorder of brain. As an increasingly aging population, AD represents a huge burden for the patients' family and the country. However, current therapeutical strategies have shown limited effectiveness. Allicin, which is the main composition of garlic, was reported to prevent the learning and memory impairment of AD mouse model. As the mechanism is not clear, in this study, we used the APP (amyloid precursor protein)/PS1 (presenilin 1) double transgenic mice, which express human mutant APP and PS1, to determine the protective effect of allicin on neurons. AD involves a broad range of clinical, cellular, and biochemical manifestations. This has led to many views of AD, e.g. the amyloid, presenilin, oxidative stress, and mitochondrial dysfunction. We confirmed that allicin improves the cognitive function of APP/PS1 double transgenic mice by reducing the expression levels of Aß, oxidative stress, and improving mitochondrial dysfunction. Application of behavioral, morphological and molecular biology, and other means were conducted to investigate the effect of allicin, which provide an experimental basis for the reliable application of allicin in the treatment of neurodegenerative diseases.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Precursor de Proteína beta-Amiloide/genética , Disfunção Cognitiva/tratamento farmacológico , Presenilina-1/genética , Ácidos Sulfínicos/administração & dosagem , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Disfunção Cognitiva/genética , Disfunção Cognitiva/patologia , Modelos Animais de Doenças , Dissulfetos , Humanos , Camundongos , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
18.
Comput Struct Biotechnol J ; 16: 77-87, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29977480

RESUMO

The field of machine learning has allowed researchers to generate and analyse vast amounts of data using a wide variety of methodologies. Artificial Neural Networks (ANN) are some of the most commonly used statistical models and have been successful in biomarker discovery studies in multiple disease types. This review seeks to explore and evaluate an integrated ANN pipeline for biomarker discovery and validation in Alzheimer's disease, the most common form of dementia worldwide with no proven cause and no available cure. The proposed pipeline consists of analysing public data with a categorical and continuous stepwise algorithm and further examination through network inference to predict gene interactions. This methodology can reliably generate novel markers and further examine known ones and can be used to guide future research in Alzheimer's disease.

19.
Data Brief ; 20: 1877-1883, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30294639

RESUMO

We herein present behavioral data regarding whether COA-Cl, a novel adenosine-like nucleic acid analog that promotes angiogenesis and features neuroprotective roles, improves cognitive and behavioral deficits in a murine model for Alzheimer׳s disease (AD). COA-Cl induced significant spatial memory improvement in the amyloid precursor protein/presenilin 2 double-transgenic mouse model of AD (PS2Tg2576 mice). Correspondingly, non-spatial novel object cognition test performance also significantly improved in COA-Cl-treated PS2Tg2576 mice; however, these mice demonstrated no significant changes in physical activity or motor performance. COA-Cl did not change the spontaneous activities and cognitive ability in the wild-type mice.

20.
Neuroimage Clin ; 17: 263-271, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29159043

RESUMO

People with Down syndrome (DS) develop Alzheimer's disease (AD) at higher rates and a younger age of onset compared to the general population. As the average lifespan of people with DS is increasing, AD is becoming an important health concern in this group. Neuroimaging is becoming an increasingly useful tool in understanding the pathogenesis of dementia development in relation to clinical symptoms. Furthermore, neuroimaging has the potential to play a role in AD diagnosis and monitoring of therapeutics. This review describes major recent findings from in vivo neuroimaging studies analysing DS and AD via ligand-based positron emission tomography (PET), [18F] fluorodeoxyglucose (FDG)-PET, structural magnetic resonance imaging (sMRI), and diffusion tensor imaging (DTI). Electroencephalography (EEG) and retinal imaging are also discussed as emerging modalities. The review is organized by neuroimaging method and assesses the relationship between cognitive decline and neuroimaging changes. We find that amyloid accumulation seen on PET occurs prior to dementia onset, possibly as a precursor to the atrophy and white matter changes seen in MRI studies. Future PET studies relating tau distribution to clinical symptoms will provide further insight into the role this protein plays in dementia development. Brain activity changes demonstrated by EEG and metabolic changes seen via FDG-PET may also follow predictable patterns that can help track dementia progression. Finally, newer approaches such as retinal imaging will hopefully overcome some of the limitations of neuroimaging and allow for detection of dementia at an earlier stage.


Assuntos
Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico por imagem , Encéfalo/patologia , Síndrome de Down/complicações , Síndrome de Down/diagnóstico por imagem , Neuroimagem , Doença de Alzheimer/patologia , Imagem de Tensor de Difusão , Síndrome de Down/patologia , Eletroencefalografia , Humanos , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons
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