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1.
Antioxidants (Basel) ; 13(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38539843

RESUMO

Alzheimer's disease is a neurodegeneration with protein deposits, altered proteolysis, and inflammatory and oxidative processes as major hallmarks. Despite the continuous search for potential therapeutic treatments, no cure is available to date. The use of natural molecules as adjuvants in the treatment of Alzheimer's disease is a very promising strategy. In this regard, ginsenosides from ginseng root show a variety of biological effects. Here, we dissected the role of ginsenosides Rg1 and Rg2 in modulating autophagy and oxidative stress in neuroblastoma cells overexpressing Aß(1-42). Key hallmarks of these cellular processes were detected through immunomethods and fluorometric assays. Our findings indicate that ginsenosides are able to upregulate autophagy in neuronal cells as demonstrated by increased levels of LC3II and Beclin-1 proteins and decreased amounts of p62. Simultaneously, an activation of lysosomal hydrolases was observed. Furthermore, autophagy activation promoted the clearance of Aß(1-42). Rg1 and Rg2 also reduced oxidative stress sources and macromolecule oxidation, promoting NRF2 nuclear translocation and the expression of antioxidant enzymes. Our data further clarify the mechanisms of action of Rg1 and Rg2, indicating new insights into their role in the management of disorders like Alzheimer's disease.

2.
Mol Neurobiol ; 60(5): 2787-2800, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36729287

RESUMO

Alzheimer's disease (AD) is a progressive neurodegeneration with dysfunctions in both the ubiquitin-proteasome system (UPS) and autophagy. Astroglia participation in AD is an attractive topic of research, but molecular patterns are partially defined and available in vitro models have technical limitations. Immortalized astrocytes from the hippocampus of 3xTg-AD and wild-type mice (3Tg-iAstro and WT-iAstro, respectively) have been obtained as an attempt to overcome primary cell line limitations and this study aims at characterizing their proteolytic systems, focusing on UPS and autophagy. Both 26S and 20S proteasomal activities were downregulated in 3Tg-iAstro, in which a shift in catalytic subunits from constitutive 20S proteasome to immunoproteasome occurred, with consequences on immune functions. In fact, immunoproteasome is the specific complex in charge of clearing damaged proteins under inflammatory conditions. Parallelly, augmented expression and activity of the lysosomal cathepsin B, enhanced levels of lysosomal-associated membrane protein 1, beclin1, and LC3-II, together with an increased uptake of monodansylcadaverine in autophagic vacuoles, suggested autophagy activation in 3Tg-iAstro. The two proteolytic pathways were linked by p62 that accumulated in 3Tg-iAstro due to both increased synthesis and decreased degradation in the UPS defective astrocytes. Treatment with 4-phenylbutyric acid, a neuroprotective small chemical chaperone, partially restored proteasome and autophagy-mediated proteolysis in 3Tg-iAstro. Our data shed light on the impaired proteostasis in 3Tg-iAstro with proteasome inhibition and autophagic compensatory activation, providing additional validation of this AD in vitro model, and propose a new mechanism of action of 4-phenylbutyric acid in neurodegenerative disorders.


Assuntos
Doença de Alzheimer , Camundongos , Animais , Proteólise , Doença de Alzheimer/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Astrócitos/metabolismo , Ubiquitina/metabolismo , Fatores de Transcrição/metabolismo , Autofagia/fisiologia
3.
Molecules ; 27(21)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36364419

RESUMO

BACKGROUND: Breast cancer is the most diagnosed cancer among women, and its incidence and mortality are rapidly growing worldwide. In this regard, plant-derived natural compounds have been shown to be effective as chemotherapeutic and preventative agents. Apricot kernels are a rich source of nutrients including proteins, lipids, fibers, and phenolic compounds and contain the aromatic cyanogenic glycoside amygdalin that has been shown to exert a cytotoxic effect on cancer cells by affecting the cell cycle, inducing apoptosis, and regulating the immune function. METHODS: Here, we describe a previously unexplored proapoptotic mechanism of action of amygdalin in breast cancer (MCF7) cells that involves the modulation of intracellular proteolysis. For comparative purposes, the same investigations were also conducted upon cell treatment with two apricot kernel aqueous extracts from Prunus armeniaca L. RESULTS: We observed that both the 20S and 26S proteasome activities were downregulated in the MCF7 cells upon 24 h treatments. Simultaneously, the autophagy cascade resulted in being impaired due to cathepsin B and L inhibition that also contributed to a reduction in cancer cell migration. The inhibition of these proteolytic systems finally promoted the activation of apoptotic events in the MCF7 cells. CONCLUSION: Collectively, our data unveil a novel mechanism of the anticancer activity of amygdalin, prompting further investigations for potential application in cancer preventative strategies.


Assuntos
Amigdalina , Neoplasias da Mama , Prunus armeniaca , Feminino , Humanos , Amigdalina/farmacologia , Proteólise , Neoplasias da Mama/tratamento farmacológico , Apoptose
4.
Int J Mol Sci ; 23(15)2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35955845

RESUMO

Alzheimer's disease (AD) is a fatal neurodegenerative disorder associated with severe dementia, progressive cognitive decline, and irreversible memory loss. Although its etiopathogenesis is still unclear, the aggregation of amyloid-ß (Aß) peptides into supramolecular structures and their accumulation in the central nervous system play a critical role in the onset and progression of the disease. On such a premise, the inhibition of the early stages of Aß aggregation is a potential prevention strategy for the treatment of AD. Since several natural occurring compounds, as well as metal-based molecules, showed promising inhibitory activities toward Aß aggregation, we herein characterized the interaction of an organoruthenium derivative of curcumin with Aß(1-40) and Aß(1-42) peptides, and we evaluated its ability to inhibit the oligomerization/fibrillogenesis processes by combining in silico and in vitro methods. In general, besides being less toxic to neuronal cells, the derivative preserved the amyloid binding ability of the parent compound in terms of equilibrium dissociation constants but (most notably) was more effective both in retarding the formation and limiting the size of amyloid aggregates by virtue of a higher hindering effect on the amyloid-amyloid elongation surface. Additionally, the complex protected neuronal cells from amyloid toxicity.


Assuntos
Doença de Alzheimer , Curcumina , Rutênio , Doença de Alzheimer/metabolismo , Amiloide/química , Peptídeos beta-Amiloides/metabolismo , Curcumina/farmacologia , Humanos , Rutênio/farmacologia
6.
Nutrients ; 14(12)2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35745108

RESUMO

Beer is the most consumed alcoholic beverage worldwide. It is rich in nutrients, and with its microbial component it could play a role in gut microbiota modulation. Conflicting data are currently available regarding the consequences of alcohol and alcohol-containing beverages on dementia and age-associated disorders including Alzheimer's disease (AD), a neurodegeneration characterized by protein aggregation, inflammatory processes and alterations of components of the gut-brain axis. The effects of an unfiltered and unpasteurized craft beer on AD molecular hallmarks, levels of gut hormones and composition of micro/mycobiota were dissected using 3xTg-AD mice. In addition, to better assess the role of yeasts, beer was enriched with the same Saccharomyces cerevisiae strain used for brewing. The treatment with the yeast-enriched beer ameliorated cognition and favored the reduction of Aß(1-42) and pro-inflammatory molecules, also contributing to an increase in the concentration of anti-inflammatory cytokines. A significant improvement in the richness and presence of beneficial taxa in the gut bacterial population of the 3xTg-AD animals was observed. In addition, the fungal order, Sordariomycetes, associated with gut inflammatory conditions, noticeably decreased with beer treatments. These data demonstrate, for the first time, the beneficial effects of a yeast-enriched beer on AD signs, suggesting gut microbiota modulation as a mechanism of action.


Assuntos
Doença de Alzheimer , Microbioma Gastrointestinal , Fármacos Neuroprotetores , Doença de Alzheimer/metabolismo , Animais , Cerveja/análise , Camundongos , Fármacos Neuroprotetores/metabolismo , Saccharomyces cerevisiae/metabolismo
7.
Biophys Chem ; 286: 106820, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35468399

RESUMO

The presence of citrullinated adenosine deaminase (ADA) was reported in the synovial fluids of rheumatoid arthritis individuals. This work reports the effects of ADA citrullination on the formation/stabilization of ADA complex with dipeptidyl peptidase IV (DPPIV). The electrophoretic mobility of in vivo citrullinated ADA was diminished compared to the native one. The biosensor binding study demonstrated approximately four-fold lower affinity of both in vivo and in vitro citrullinated ADAs to DPPIV (KD = 161 ± 51.3 and 171 ± 52.2 nM, respectively) compared with wild ADA (KD = 38 ± 9.4 nM). These results were confirmed by examining the ADA interaction with DPPIV using size-exclusion chromatography and fluorescence anisotropy methods. The computational modeling of Arg142 â†’ Cit142 modification in ADA showed a local structural rearrangement and a less favorable binding affinity to DPPIV. According to these observations, citrullinated ADA being a possible target triggering autoimmunity hinders also the formation of ADA-DPPIV complex, essential in immune system function.


Assuntos
Adenosina Desaminase , Citrulinação , Dipeptidil Peptidase 4 , Adenosina Desaminase/química , Adenosina Desaminase/metabolismo , Dipeptidil Peptidase 4/química , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidase 4/metabolismo , Humanos
8.
Clin Nutr ; 41(3): 698-708, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35158177

RESUMO

BACKGROUND & AIMS: Alzheimer's disease (AD) and age-related dementias represent a major and increasing global health challenge. Unhealthy diet and lifestyle can unbalance the intestinal microbiota composition and, consequently energy metabolism, contributing to AD pathogenesis. Impairment of cerebral cholesterol metabolism occurs in both aging and AD, and lipid-lowering agents have been associated to a lower risk of neurodegenerative diseases, but the link between blood lipid profile and AD remains a matter of debate. Recently, probiotics have emerged as a promising and safe strategy to manipulate gut microbiota composition and increase the host health status through a multi-level mechanism that is currently under investigation. Specifically, oral supplementation with a multi-strain probiotic formulation (SLAB51) reduced amyloid beta aggregates and brain damages in a triple transgenic mouse model of AD (3xTg-AD). Treated mice showed improved cognitive functions in response to an enrichment of gut anti-inflammatory metabolites, increased plasma concentrations of neuroprotective gut hormones, and ameliorated glucose uptake and metabolism. METHODS: This work focuses on the evaluation of the effects of SLAB51 chronic administration on lipid metabolism in 3xTg-AD mice and the respective wild-type counterpart. On this purpose, 8 weeks old mice were orally administered with SLAB51 for 4 and 12 months to analyze the plasma lipid profile (using lipidomic analyses and enzymatic colorimetric assays), along with the cerebral and hepatic expression levels of key regulators of cholesterol metabolism (through Western blotting and ELISA). RESULTS: Upon probiotics administration, cholesterol biosynthesis was inhibited in AD mice with a process involving sterol regulatory element binding protein 1c and liver X receptors mediated pathways. Decreased plasma and brain concentration of 27-hydroxycholesterol and increased brain expression of cholesterol 24S-hydroxylase indicated that alternative pathways of bile acid synthesis are influenced. The plasmatic increase of arachidonic acid in treated AD mice reflects dynamic interactions among several actors of a complex inflammatory response, in which polyunsaturated fatty acids can compete each other and simultaneously co-operate in the resolution of inflammation. CONCLUSIONS: These evidence, together with the hypocholesterolemic effects, the ameliorated fatty acids profile and the decreased omega 6/omega 3 ratio successfully demonstrated that microbiota modulation through probiotics can positively change lipid composition in AD mice, with arachidonic acid representing one important hub metabolite in the interactions among probiotic-induced lipid profile changes, insulin sensitivity, and inflammation.


Assuntos
Doença de Alzheimer , Microbioma Gastrointestinal , Doença de Alzheimer/metabolismo , Doença de Alzheimer/terapia , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/farmacologia , Animais , Ácidos Araquidônicos/farmacologia , Humanos , Inflamação/complicações , Metabolismo dos Lipídeos , Lipídeos/farmacologia , Camundongos
9.
J Biol Chem ; 298(3): 101669, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35120922

RESUMO

The secreted form of the enzyme nicotinamide phosphoribosyltransferase (NAMPT), which catalyzes a key reaction in intracellular NAD biosynthesis, acts as a damage-associated molecular pattern triggering Toll-like receptor 4 (TLR4)-mediated inflammatory responses. However, the precise mechanism of interaction is unclear. Using an integrated approach combining bioinformatics and functional and structural analyses, we investigated the interaction between NAMPT and TLR4 at the molecular level. Starting from previous evidence that the bacterial ortholog of NAMPT cannot elicit the inflammatory response, despite a high degree of structural conservation, two positively charged areas unique to the human enzyme (the α1-α2 and ß1-ß2 loops) were identified as likely candidates for TLR4 binding. However, alanine substitution of the positively charged residues within these loops did not affect either the oligomeric state or the catalytic efficiency of the enzyme. The kinetics of the binding of wildtype and mutated NAMPT to biosensor-tethered TLR4 was analyzed. We found that mutations in the α1-α2 loop strongly decreased the association rate, increasing the KD value from 18 nM, as determined for the wildtype, to 1.3 µM. In addition, mutations in the ß1-ß2 loop or its deletion increased the dissociation rate, yielding KD values of 0.63 and 0.22 µM, respectively. Mutations also impaired the ability of NAMPT to trigger the NF-κB inflammatory signaling pathway in human cultured macrophages. Finally, the involvement of the two loops in receptor binding was supported by NAMPT-TLR4 docking simulations. This study paves the way for future development of compounds that selectively target eNAMPT/TLR4 signaling in inflammatory disorders.


Assuntos
Citocinas , Nicotinamida Fosforribosiltransferase , Receptor 4 Toll-Like , Citocinas/genética , Citocinas/metabolismo , Humanos , NAD/metabolismo , NF-kappa B/metabolismo , Nicotinamida Fosforribosiltransferase/genética , Nicotinamida Fosforribosiltransferase/metabolismo , Ligação Proteica , Transdução de Sinais , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
10.
Nanomaterials (Basel) ; 11(7)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209361

RESUMO

Silver nanoparticles (AgNPs) can be used as a surface plasmon resonance (SPR) colorimetric sensor; the correlation between the SPR phenomenon and the aggregation state of nanoparticle allows the real-time detection of a target molecule. Surface functionalization of NPs with proper molecular baits is often performed to establish the selectivity of the sensor. This work reports on the synthesis of AgNPs under reducing conditions and on the functionalization thereof with mercaptoundecanoic acid (11-MUA). UV-VIS Spectroscopy confirmed the formation of AgNPs, eliciting a surface plasmon absorption band (SPAB) at 393 nm that shifted to 417 nm upon surface coating. Dynamic light scattering was used to investigate the surface coatings; moreover, pelleted AgNPs@11MUA nanoparticles were characterized by scanning electron microscopy (SEM), energy dispersive X-ray analyzers (EDX), and infrared spectroscopy to corroborate the presence of 11MUA on the surface. Most interestingly, the resulting AgNPs@11MUA selectively detected micromolar levels of Ni2+, also in the presence of other cations such as Mn2+, Co2+, Cd2+, Cu2+, Zn2+, Fe2+, Hg2+, Pb2+, and Cr3+.

11.
Mol Nutr Food Res ; 65(18): e2100380, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34318994

RESUMO

INTRODUCTION: Alzheimer's disease (AD) is a progressive neurodegeneration characterized by extensive protein aggregation and deposition in the brain, associated with defective proteasomal and autophagic-lysosomal proteolytic pathways. Since current drugs can only reduce specific symptoms, the identification of novel treatments is a major concern in AD research. Among natural compounds, (poly)phenols and their derivatives/metabolites are emerging as candidates in AD prevention due to their multiple beneficial effects. This study aims to investigate the ability of a selection of phenyl-γ-valerolactones, gut microbiota-derived metabolites of flavan-3-ols, to modulate the functionality of cellular proteolytic pathways. METHODS AND RESULTS: Neuronal SH-SY5Y cells transfected with either the wild-type or the 717 valine-to-glycine amyloid precursor protein mutated gene are used as an AD model and treated with 5-(4'-hydroxyphenyl)-γ-valerolactone, 5-(3',4'-dihydroxyphenyl)-γ-valerolactone and 5-(3'-hydroxyphenyl)-γ-valerolactone-4'-sulfate. Combining in vitro and in silico studies, it is observed that the phenyl-γ-valerolactones of interest modulated cellular proteolysis via proteasome inhibition and consequent autophagy upregulation and inhibited cathepsin B activity, eventually reducing the amount of intra- and extracellular amyloid-beta (1-42) peptides. CONCLUSION: The findings of this study establish, for the first time, that these metabolites exert a neuroprotective activity by regulating intracellular proteolysis and confirm the role of autophagy and cathepsin B as possible targets of AD preventive/therapeutic strategies.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Flavonoides/metabolismo , Lactonas/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fragmentos de Peptídeos/metabolismo , Doença de Alzheimer/metabolismo , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Catepsina B/metabolismo , Linhagem Celular Tumoral , Microbioma Gastrointestinal , Humanos , Ligação de Hidrogênio , Lactonas/química , Simulação de Acoplamento Molecular , Neurônios/patologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia , Complexo de Endopeptidases do Proteassoma/química , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise
12.
FEBS J ; 288(9): 2836-2855, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32969566

RESUMO

The gut microbiota coevolves with its host, and numerous factors like diet, lifestyle, drug intake and geographical location continuously modify its composition, deeply influencing host health. Recent studies demonstrated that gut dysbiosis can alter normal brain function through the so-called gut-brain axis, a bidirectional communication network between the central nervous system and the gastrointestinal tract, thus playing a key role in the pathogenesis of neurodegenerative disorders, such as Alzheimer's disease (AD). In this perspective, in the constant search for novel treatments in AD, the rational modulation of gut microbiota composition could represent a promising approach to prevent or delay AD onset or to counteract its progression. Preclinical and human studies on microbiota modulation through oral bacteriotherapy and faecal transplantation showed anti-inflammatory and antioxidant effects, upregulation of plasma concentration of neuroprotective hormones, restoration of impaired proteolytic pathways, amelioration of energy homeostasis with consequent decrease of AD molecular hallmarks and improvement of behavioural and cognitive performances. In this review, we dissect the role of gut microbiota in AD and highlight recent advances in the development of new multitarget strategies for microbiota modulation to be used as possible preventative and therapeutic approaches in AD.


Assuntos
Doença de Alzheimer/microbiologia , Microbioma Gastrointestinal/genética , Inflamação/tratamento farmacológico , Doença de Alzheimer/patologia , Doença de Alzheimer/prevenção & controle , Doença de Alzheimer/terapia , Antioxidantes/uso terapêutico , Encéfalo/metabolismo , Encéfalo/patologia , Humanos , Inflamação/genética , Fármacos Neuroprotetores/uso terapêutico
13.
Aging (Albany NY) ; 12(16): 15995-16020, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32855357

RESUMO

Alzheimer's disease (AD) is a progressive neurodegeneration characterized by neuron death ending in memory and cognitive decline. A major concern in AD research is the identification of new therapeutics that could prevent or delay the onset of the disorder, with current treatments being effective only in reducing symptoms. In this perspective, the use of engineered probiotics as therapeutic tools for the delivery of molecules to eukaryotic cells is finding application in several disorders. This work introduces a new strategy for AD treatment based on the use of a Lactobacilluslactis strain carrying one plasmid (pExu) that contains a eukaryotic expression cassette encoding the human p62 protein. 3xTg-AD mice orally administered with these bacteria for two months showed an increased expression of endogenous p62 in the brain, with a protein delivery mechanism involving both lymphatic vessels and neural terminations, and positive effects on the major AD hallmarks. Mice showed ameliorated memory, modulation of the ubiquitin-proteasome system and autophagy, reduced levels of amyloid peptides, and diminished neuronal oxidative and inflammatory processes. Globally, we demonstrate that these extremely safe, non-pathogenic and non-invasive bacteria used as delivery vehicles for the p62 protein represent an innovative and realistic therapeutic approach in AD.


Assuntos
Doença de Alzheimer/prevenção & controle , Encéfalo/metabolismo , Terapia Genética , Vetores Genéticos , Lactobacillus/genética , Probióticos , Proteína Sequestossoma-1/genética , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Animais , Comportamento Animal , Encéfalo/patologia , Encéfalo/fisiopatologia , Cognição , Modelos Animais de Doenças , Microbioma Gastrointestinal , Mediadores da Inflamação/metabolismo , Lactobacillus/metabolismo , Masculino , Memória , Camundongos Transgênicos , Teste de Campo Aberto , Estresse Oxidativo , Proteína Sequestossoma-1/biossíntese
14.
Sci Rep ; 10(1): 13150, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32753591

RESUMO

Virtual screening techniques and in vitro binding/inhibitory assays were used to search within a set of more than 8,000 naturally occurring small ligands for candidate inhibitors of 8-hydroxy-5-deazaflavin:NADPH oxidoreductase (FNO) from Methanobrevibacter smithii, the enzyme that catalyses the bidirectional electron transfer between NADP+ and F420H2 during the intestinal production of CH4 from CO2. In silico screening using molecular docking classified the ligand-enzyme complexes in the range between - 4.9 and - 10.5 kcal/mol. Molecular flexibility, the number of H-bond acceptors and donors, the extent of hydrophobic interactions, and the exposure to the solvent were the major discriminants in determining the affinity of the ligands for FNO. In vitro studies on a group of these ligands selected from the most populated/representative clusters provided quantitative kinetic, equilibrium, and structural information on ligands' behaviour, in optimal agreement with the predictive computational results.


Assuntos
Proteínas de Bactérias , Inibidores Enzimáticos/química , Methanobrevibacter/enzimologia , NADH NADPH Oxirredutases , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/química , Domínio Catalítico , NADH NADPH Oxirredutases/antagonistas & inibidores , NADH NADPH Oxirredutases/química
15.
ChemMedChem ; 15(1): 105-113, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31701643

RESUMO

The molecular targets and the modes of action behind the cytotoxicity of two structurally established N,O- or N,N-hydrazone ruthenium(II)-arene complexes were explored in human breast adenocarcinoma cells (MCF-7) and paralleled in non-cancerous and cisplatin-resistant counterparts (MCF-10A and MCF-7CR respectively). Both complexes, [Ru(hmb)(L1)Cl] (1, L1=4-((2-(2,4-dinitrophenyl)hydrazono)(phenyl)methyl)-3-methyl-1-phenyl-1H-pyrazol-5-olate) and [Ru(cym)(L2)Cl] (2, L2=1-((3-methyl-5-oxo-1-phenyl-1H-pyrazol-4(5H)-ylidene)(phenyl)methyl)-2-(pyridin-2-yl)hydrazin-1-ide), reversibly interact with moderate-to-high affinity with a number of molecular targets in cell-free assays, namely serum albumin, DNA, the 20S proteasome and hydroxymethylglutaryl-CoA reductase. Most interestingly, only 2 readily crosses the cell membrane and preserves its binding/modulatory ability toward the targets of interest upon rapid cellular internalization. The resulting action at multiple levels of the cancer cascade is likely the cause for the selective sensitization of tumour cells to p27-mediated apoptotic death, and for the ability of 2 to overcome the drug resistance problem.


Assuntos
Antineoplásicos/química , Complexos de Coordenação/química , Hidrazonas/química , Rutênio/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Sítios de Ligação , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular/efeitos dos fármacos , Complexos de Coordenação/metabolismo , Complexos de Coordenação/farmacologia , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , DNA/química , DNA/metabolismo , Humanos , Hidroximetilglutaril-CoA Redutases/química , Hidroximetilglutaril-CoA Redutases/metabolismo , Cinética , Simulação de Acoplamento Molecular , Conformação de Ácido Nucleico , Ligação Proteica
16.
Neurobiol Aging ; 87: 35-43, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31813629

RESUMO

Cerebral glucose homeostasis deregulation has a role in the pathogenesis and the progression of Alzheimer's disease (AD). Current therapies delay symptoms without definitively curing AD. We have previously shown that probiotics counteract AD progression in 3xTg-AD mice modifying gut microbiota and inducing energy metabolism and glycolysis-gluconeogenesis. Ameliorated cognition is based on higher neuroprotective gut hormones concentrations, reduced amyloid-ß burden, and restored proteolytic pathways. Here, we demonstrate that probiotics oral administration improves glucose uptake in 3xTg-AD mice by restoring the brain expression levels of key glucose transporters (GLUT3, GLUT1) and insulin-like growth factor receptor ß, in accordance with the diminished phosphorylation of adenosine monophosphate-activated protein kinase and protein-kinase B (Akt). In parallel, phosphorylated tau aggregates decrease in treated mice. Probiotics counteract the time-dependent increase of glycated hemoglobin and the accumulation of advanced glycation end products in AD mice, consistently with memory improvement. Collectively, our data elucidate the mechanism through which gut microbiota manipulation ameliorates impaired glucose metabolism in AD, finally delaying the disease progression.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/terapia , Encéfalo/metabolismo , Microbioma Gastrointestinal , Glucose/metabolismo , Homeostase , Probióticos/administração & dosagem , Probióticos/farmacologia , Doença de Alzheimer/etiologia , Doença de Alzheimer/microbiologia , Peptídeos beta-Amiloides/metabolismo , Animais , Modelos Animais de Doenças , Metabolismo Energético/efeitos dos fármacos , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 3/metabolismo , Glicólise/efeitos dos fármacos , Camundongos Transgênicos , Proteínas tau/metabolismo
17.
Toxins (Basel) ; 11(10)2019 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-31569379

RESUMO

The yeast Wickerhamomyces anomalus has several applications in the food industry due to its antimicrobial potential and wide range of biotechnological properties. In particular, a specific strain of Wickerhamomyces anomalus isolated from the malaria mosquito Anopheles stephensi, namely WaF17.12, was reported to secrete a killer toxin with strong anti-plasmodial effect on different developmental stages of Plasmodium berghei; therefore, we propose its use in the symbiotic control of malaria. In this study, we focused on the identification/characterization of the protein toxin responsible for the observed antimicrobial activity of the yeast. For this purpose, the culture medium of the killer yeast strain WaF17.12 was processed by means of lateral flow filtration, anion exchange and gel filtration chromatography, immunometric methods, and eventually analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Based on this concerted approach, we identified a protein with a molecular weight of approximately 140 kDa and limited electrophoretic mobility, corresponding to a high molecular weight ß-glucosidase, as confirmed by activity tests in the presence of specific inhibitors.


Assuntos
Anopheles/microbiologia , Glicosídeo Hidrolases/isolamento & purificação , Micotoxinas/isolamento & purificação , Pichia/patogenicidade , Animais , Cromatografia Líquida , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/farmacologia , Simulação de Acoplamento Molecular , Micotoxinas/química , Micotoxinas/farmacologia , Espectrometria de Massas em Tandem
18.
Talanta ; 184: 35-41, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29674053

RESUMO

African swine fever (ASF) virus is a DNA virus responsible for a severe haemorrhagic fever in pigs, which (still in the absence of vaccination strategies) results in high mortality rates. Herein, we present a biosensor-based method for the detection of ASF viral DNA in the blood of pigs. The biosensor exploits a single-strand DNA probe with locked nucleic acid nucleotides (LNA) substitutions as the complementary recognition element for the conserved region of vp72 gene of ASF virus. The biosensor was calibrated using qPCR-quantified ASF viral DNA extracted from the blood of pigs experimentally infected with the virulent Italian isolate 49/08, genotype I. Globally, the proposed biosensor showed good sensitivity and specificity, with the limits of detection (LOD) and quantification (LOQ) being 178 and 245 copies/µL of genomic ASF viral DNA, respectively. The reversible nature of the interaction between the DNA/LNA probe and the target DNA sequence granted multiple rapid analyses, with up to 40 analyses per single surface possible, and a single test requiring approximately 5 min. When applied to non-amplified DNA extracts from the blood of field-infected pigs, the assay discriminated between ASFV-infected and ASFV non-infected animals, and allowed the rapid quantification of ASF viral DNA, with values falling in the range 373-1058 copies/µL of genomic ASFV DNA. In this range, excellent correlation was observed between the results of this biosensor and OIE-approved qPCR. This method represents a promising screening assay for preliminary ASF diagnosis, having the major advantages in the relative rapidity, ease-of-use, the reusability of the sensing surface, and low cost per single test.


Assuntos
Vírus da Febre Suína Africana/isolamento & purificação , Febre Suína Africana/diagnóstico , Técnicas Biossensoriais , DNA Viral/química , Oligonucleotídeos/química , Animais , DNA Viral/genética , Suínos
19.
Mol Neurobiol ; 55(10): 7987-8000, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29492848

RESUMO

The gut-brain axis is a bidirectional communication network functionally linking the gut and the central nervous system (CNS). Based on this, the rational manipulation of intestinal microbiota represents a novel attractive therapeutic strategy for the treatment of CNS-associated disorders. In this study, we explored the properties of a probiotic formulation (namely SLAB51) in counteracting brain oxidative damages associated with Alzheimer's disease (AD). Specifically, transgenic AD mice (3xTg-AD) were treated with SLAB51 and the effects on protein oxidation, neuronal antioxidant defence and repair systems were monitored, with the particular focus on the role of SIRT1-related pathways. We demonstrated that SLAB51 markedly reduced oxidative stress in AD mice brain by activating SIRT1-dependent mechanisms, thus representing a promising therapeutic adjuvant in AD treatment.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Antioxidantes/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Probióticos/uso terapêutico , Sirtuína 1/metabolismo , Animais , DNA/metabolismo , Reparo do DNA/efeitos dos fármacos , Modelos Animais de Doenças , Lipídeos/química , Masculino , Camundongos Transgênicos , Oxirredução , Receptores do Ácido Retinoico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
20.
Sci Rep ; 7(1): 13169, 2017 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-29030601

RESUMO

Wheat amylase/trypsin bi-functional inhibitors (ATIs) are protein stimulators of innate immune response, with a recently established role in promoting both gastrointestinal and extra-gastrointestinal inflammatory syndromes. These proteins have been reported to trigger downstream intestinal inflammation upon activation of TLR4, a member of the Toll-like family of proteins that activates signalling pathways and induces the expression of immune and pro-inflammatory genes. In this study, we demonstrated the ability of ATI to directly interact with TLR4 with nanomolar affinity, and we kinetically and structurally characterized the interaction between these macromolecules by means of a concerted approach based on surface plasmon resonance binding analyses and computational studies. On the strength of these results, we designed an oligopeptide capable of preventing the formation of the complex between ATI and the receptor.


Assuntos
Técnicas Biossensoriais , Proteínas de Plantas/metabolismo , Receptor 4 Toll-Like/metabolismo , Triticum/metabolismo , Inibidores da Tripsina/metabolismo , Ligação Proteica , Ressonância de Plasmônio de Superfície
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