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1.
Int J Mol Sci ; 25(14)2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39063111

RESUMO

Inflammatory bowel disease (IBD) incidence has increased in the last decades due to changes in dietary habits. IBDs are characterized by intestinal epithelial barrier disruption, increased inflammatory mediator production and excessive tissue injury. Since the current treatments are not sufficient to achieve and maintain remission, complementary and alternative medicine (CAM) becomes a primary practice as a co-adjuvant for the therapy. Thus, the intake of functional food enriched in vegetal extracts represents a promising nutritional strategy. This study evaluates the anti-inflammatory effects of artichoke, caihua and fenugreek vegetal extract original blend (ACFB) in an in vitro model of gut barrier mimicking the early acute phases of the disease. Caco2 cells cultured on transwell supports were treated with digested ACFB before exposure to pro-inflammatory cytokines. The pre-treatment counteracts the increase in barrier permeability induced by the inflammatory stimulus, as demonstrated by the evaluation of TEER and CLDN-2 parameters. In parallel, ACFB reduces p65NF-κB pro-inflammatory pathway activation that results in the decrement of COX-2 expression as PGE2 and IL-8 secretion. ACFB properties might be due to the synergistic effects of different flavonoids, indicating it as a valid candidate for new formulation in the prevention/mitigation of non-communicable diseases.


Assuntos
Flavonoides , NF-kappa B , Extratos Vegetais , Humanos , Células CACO-2 , Extratos Vegetais/farmacologia , Flavonoides/farmacologia , NF-kappa B/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/tratamento farmacológico , Interleucina-8/metabolismo , Transdução de Sinais/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Ciclo-Oxigenase 2/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Trigonella/química , Dinoprostona/metabolismo
2.
Int J Mol Sci ; 24(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37298151

RESUMO

Epigenetic changes, host-gut microbiota interactions, and environmental factors contribute to inflammatory bowel disease (IBD) onset and progression. A healthy lifestyle may help to slow down the chronic or remitting/relapsing intestinal tract inflammation characteristic of IBD. In this scenario, the employment of a nutritional strategy to prevent the onset or supplement disease therapies included functional food consumption. Its formulation consists of the addition of a phytoextract enriched in bioactive molecules. A good candidate as an ingredient is the Cinnamon verum aqueous extract. Indeed, this extract, subjected to a process of gastrointestinal digestion simulation (INFOGEST), exhibits beneficial antioxidant and anti-inflammatory properties in an in vitro model of the inflamed intestinal barrier. Here, we deepen the study of the mechanisms related to the effect of digested cinnamon extract pre-treatment, showing a correlation between transepithelial electrical resistance (TEER) decrement and alterations in claudin-2 expression under Tumor necrosis factor-α/Interleukin-1ß (TNF-α/IL-1) ß cytokine administration. Our results show that pre-treatment with cinnamon extract prevents TEER loss by claudin-2 protein level regulation, influencing both gene transcription and autophagy-mediated degradation. Hence, cinnamon polyphenols and their metabolites probably work as mediators in gene regulation and receptor/pathway activation, leading to an adaptive response against renewed insults.


Assuntos
Cinnamomum zeylanicum , Doenças Inflamatórias Intestinais , Humanos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Claudina-2 , Interleucina-1beta/genética , Casca de Planta/metabolismo , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/metabolismo , Expressão Gênica
3.
Molecules ; 27(3)2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35164314

RESUMO

Age-related injuries are often connected to alterations in redox homeostasis. The imbalance between free radical oxygen species and endogenous antioxidants defenses could be associated with a growing risk of transient ischemic attack and stroke. In this context, a daily supply of dietary antioxidants could counteract oxidative stress occurring during ischemia/reperfusion injury (I/R), preventing brain damage. Here we investigated the potential antioxidant properties of coffee-derived circulating metabolites and a coffee pulp phytoextract, testing their efficacy as ROS scavengers in an in vitro model of ischemia. Indeed, the coffee fruit is an important source of phenolic compounds, such as chlorogenic acids, present both in the brewed seed and in the discarded pulp. Therefore, rat brain endothelial cells, subjected to oxygen and glucose deprivation (OGD) and recovery (ogR) to mimic reperfusion, were pretreated or not with coffee by-products. The results indicate that, under OGD/ogR, the ROS accumulation was reduced by coffee by-product. Additionally, the coffee extract activated the Nrf2 antioxidant pathway via Erk and Akt kinases phosphorylation, as shown by increased Nrf2 and HO-1 protein levels. The data indicate that the daily intake of coffee by-products as a dietary food supplement represents a potential nutritional strategy to counteract aging.


Assuntos
Antioxidantes/farmacologia , Coffea/química , Fator 2 Relacionado a NF-E2/agonistas , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Traumatismo por Reperfusão/terapia , Animais , Antioxidantes/química , Isquemia Encefálica/metabolismo , Isquemia Encefálica/terapia , Linhagem Celular , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fenóis/química , Extratos Vegetais/química , Ratos , Traumatismo por Reperfusão/metabolismo
4.
Biochim Biophys Acta ; 1860(4): 746-56, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26774643

RESUMO

BACKGROUND: Amyloid ß (Aß) peptide aggregation is the main molecular mechanism underlying the development of Alzheimer's disease, the most widespread form of senile dementia worldwide. Increasing evidence suggests that the key factor leading to impaired neuronal function is accumulation of water-soluble Aß oligomers rather than formation of the senile plaques created by the deposition of large fibrillary aggregates of Aß. However, several questions remain about the preliminary steps and the progression of Aß oligomerization. METHODS: We show that the initial stages of the aggregation of fluorescently labeled Aß can be determined with a high degree of precision and at physiological (i.e., nanomolar) concentrations by using either steady-state fluorimetry or time-correlated single-photon counting. RESULTS: We study the dependence of the oligomerization extent and rate on the Aß concentration. We determine the chemical binding affinity of fluorescently labeled Aß for liposomes that have been recently shown to be pharmacologically active in vivo, reducing the Aß burden within the brain. We also probe their capacity to hinder the Aß oligomerization process in vitro. CONCLUSIONS: We introduced a fluorescence assay allowing investigation of the earliest steps of Aß oligomerization, the peptide involved in Alzheimer's disease. The assay proved to be sensitive even at Aß concentrations as low as those physiologically observed in the cerebrospinal fluid. GENERAL SIGNIFICANCE: This work represents an extensive and quantitative study on the initial events of Aß oligomerization at physiological concentration. It may enhance our comprehension of the molecular mechanisms leading to Alzheimer's disease, thus paving the way to novel therapeutic strategies.


Assuntos
Peptídeos beta-Amiloides/química , Lipossomos/química , Fragmentos de Peptídeos/química , Agregação Patológica de Proteínas , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Humanos , Fragmentos de Peptídeos/metabolismo , Espectrometria de Fluorescência
5.
Nanomedicine ; 10(7): 1583-90, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24333591

RESUMO

Targeting amyloid-ß peptide (Aß) within the brain is a strategy actively sought for therapy of Alzheimer's disease (AD). We investigated the ability of liposomes bi-functionalized with phosphatidic acid and with a modified ApoE-derived peptide (mApoE-PA-LIP) to affect Aß aggregation/disaggregation features and to cross in vitro and in vivo the blood-brain barrier (BBB). Surface plasmon resonance showed that bi-functionalized liposomes strongly bind Aß (kD=0.6 µM), while Thioflavin-T and SDS-PAGE/WB assays show that liposomes inhibit peptide aggregation (70% inhibition after 72 h) and trigger the disaggregation of preformed aggregates (60% decrease after 120 h incubation). Moreover, experiments with dually radiolabelled LIP suggest that bi-functionalization enhances the passage of radioactivity across the BBB either in vitro (permeability=2.5×10(-5) cm/min, 5-fold higher with respect to mono-functionalized liposomes) or in vivo in healthy mice. Taken together, our results suggest that mApoE-PA-LIP are valuable nanodevices with a potential applicability in vivo for the treatment of AD. From the clinical editor: Bi-functionalized liposomes with phosphatidic acid and a modified ApoE-derived peptide were demonstrated to influence Aß aggregation/disaggregation as a potential treatment in an Alzheimer's model. The liposomes were able to cross the blood-brain barrier in vitro and in vivo. Similar liposomes may become clinically valuable nanodevices with a potential applicability for the treatment of Alzheimer's disease.


Assuntos
Doença de Alzheimer/terapia , Apolipoproteínas E/química , Barreira Hematoencefálica , Lipossomos , Peptídeos/química , Ácidos Fosfatídicos/química , Apolipoproteínas E/administração & dosagem , Western Blotting , Eletroforese em Gel de Poliacrilamida , Humanos , Ácidos Fosfatídicos/administração & dosagem , Ressonância de Plasmônio de Superfície
6.
Artigo em Inglês | MEDLINE | ID: mdl-38791840

RESUMO

The transition to higher education at University is a critical moment for young adults to acquire unhealthy habits regarding physical activity (PA) and adherence to a healthy diet. Negative behaviors might be maintained in the years to come with a major risk of suffering from a Non-Communicable Disease. This study aims to determine the relationship between diet and PA in the student community of University of Milano-Bicocca. Students between 18 and 30 years old completed an online survey (6949 students). Two analyses of covariance (ANCOVA), chi-square tests of independence, and a binomial logistic regression were performed to examine the relationship between adequacy of food consumption and PA, in association also with sociodemographic characteristics. Data show a strong correlation between behaviors analyzed, with a proportional positive association between PA and healthy diet. Nevertheless, a third of the sample students incur in incorrect habits for both diet and PA. Further, students performing intensive PA have the healthiest food consumption in general but the worst red meat and pork intake. Accordingly, men practice more PA but have a less adequate diet, exactly contrary to women. In conclusion, policies promoting consciousness of well-being would transform Universities into healthy hubs for virtuous habits.


Assuntos
Exercício Físico , Comportamento Alimentar , Estudantes , Humanos , Estudantes/estatística & dados numéricos , Estudantes/psicologia , Masculino , Feminino , Universidades , Adulto Jovem , Adulto , Adolescente , Estilo de Vida , Itália , Dieta , Inquéritos e Questionários , Comportamentos Relacionados com a Saúde
7.
FASEB J ; 26(7): 3065-74, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22508690

RESUMO

Mutations in the presenilin 1 (PS1) gene are associated with early onset familial Alzheimer's disease (FAD). In this study, we found that the expression of mutant-PS1 in stable transfectants of SH-SY5Y neuroblastoma cells results in a reduction of the biosynthesis and steady-state levels of glucosylceramide. As an in vivo corroboration of these data, there was a significant reduction of brain glucosylceramide and gangliosides in an animal model of FAD. In mutant-PS1-transfectants (I143T, G384A), immunocytochemistry disclosed a remarkable reduction of glucosylceramide synthase (GlcT-1)-like immunoreactivity in the cells when compared with those of mock- and wild-PS1 transfectants. Immunoprecipitation of GlcT-1 protein from mutant-PS1 transfectants demonstrated a marked reduction in GlcT-1 protein, but there was no reduction in the levels of GlcT-1 mRNA. Both coprecipitation and γ-secretase inhibition experiments suggest that mutant-PS1 seems to form a complex with GlcT-1 protein and to be involved in GlcT-1 degradation, which was never found in other cell types. Thus, mutations in the PS1 gene result in profound glycosphingolipids abnormalities by abnormal molecular interaction with GlcT-1.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Glicoesfingolipídeos/biossíntese , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Presenilina-1/genética , Presenilina-1/metabolismo , Substituição de Aminoácidos , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Animais , Sequência de Bases , Encéfalo/metabolismo , Carbamatos/farmacologia , Linhagem Celular , Primers do DNA/genética , Dipeptídeos/farmacologia , Inibidores Enzimáticos/farmacologia , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Humanos , Camundongos , Camundongos Transgênicos , Mutação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transfecção
8.
Mol Cell Neurosci ; 49(4): 415-22, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22326856

RESUMO

Although the diverse triggers of AD are still under debate, the hypothesis of the contribution of cerebrovascular deficiencies has emerged in recent years. Cerebrovascular dysfunction may precede cognitive decline and onset of neurodegeneration. Indeed, the toxic Aß(42) aggregates constituting senile plaques, one of AD hallmarks, is often detected as amorphous material or fine fibrils in the brain capillary of AD patients. Aß(42) causing cerebral microangiopathy might originate either from the circulating blood, the vessel wall itself or the brain parenchyma. In the present investigation we show, for the first time, that in rat brain capillary endothelial cells (RBE4), in vitro oxygen glucose deprivation treatment elicits 250% of Aß(42) peptide production increase through a mechanism that involves the hypoxia inducible factor-1-mediated ß-secretase (BACE1) up-regulation. Furthermore, we observed a time dependent increase of amyloid protein precursor (AßPP) gene and protein expression, confirming previous reports which established the existence of AßPP in the cerebrovascular domain. Our experimental evidences point out that ischemic events may directly contribute in brain capillary endothelial cells to the enhancement of the amyloidogenic metabolism, leading to intracellular deposition of Aß(42). This events may contribute to the impairment of Aß brain clearance and AD related blood brain barrier dysfunctions.


Assuntos
Peptídeos beta-Amiloides/biossíntese , Barreira Hematoencefálica/metabolismo , Hipóxia Celular/fisiologia , Células Endoteliais/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Fragmentos de Peptídeos/biossíntese , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/biossíntese , Animais , Ácido Aspártico Endopeptidases/biossíntese , Western Blotting , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Capilares/metabolismo , Ensaio de Imunoadsorção Enzimática , Perfilação da Expressão Gênica , Glucose/deficiência , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Neurônios/metabolismo , RNA Mensageiro/análise , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Artigo em Inglês | MEDLINE | ID: mdl-36901403

RESUMO

Particulate matter (PM) is a harmful component of urban air pollution and PM2.5, in particular, can settle in the deep airways. The RAS system plays a crucial role in the pathogenesis of pollution-induced inflammatory diseases: the ACE/AngII/AT1 axis activates a pro-inflammatory pathway counteracted by the ACE2/Ang(1-7)/MAS axis, which in turn triggers an anti-inflammatory and protective pathway. However, ACE2 acts also as a receptor through which SARS-CoV-2 penetrates host cells to replicate. COX-2, HO-1, and iNOS are other crucial proteins involved in ultrafine particles (UFP)-induced inflammation and oxidative stress, but closely related to the course of the COVID-19 disease. BALB/c male mice were subjected to PM2.5 sub-acute exposure to study its effects on ACE2 and ACE, COX-2, HO-1 and iNOS proteins levels, in the main organs concerned with the pathogenesis of COVID-19. The results obtained show that sub-acute exposure to PM2.5 induces organ-specific modifications which might predispose to greater susceptibility to severe symptomatology in the case of SARS-CoV-2 infection. The novelty of this work consists in using a molecular study, carried out in the lung but also in the main organs involved in the disease, to analyze the close relationship between exposure to pollution and the pathogenesis of COVID-19.


Assuntos
COVID-19 , Animais , Humanos , Masculino , Camundongos , Enzima de Conversão de Angiotensina 2 , Ciclo-Oxigenase 2 , Pandemias , Material Particulado , Peptidil Dipeptidase A/metabolismo , SARS-CoV-2
10.
Artigo em Inglês | MEDLINE | ID: mdl-36497802

RESUMO

Chronic noncommunicable diseases (NCDs) have become the major cause of morbidity and mortality in the Maldives, triggered by the nutrition transition to a "Western diet" that dramatically increases the prevalence of excess weight and hypertension. Our study aimed to evaluate dietary habits, blood pressure (BP) and body mass index in Maghoodoo Public School's students. A sample of 145 students (72 males and 73 females, age 9.37 ± 2.97 years) was enrolled. Factors causing excess weight were investigated through descriptive statistics. The relationship between blood pressure percentiles and possible influencing factors was investigated by a linear regression model.. Excess weight was present in 15.07% and 12.5% females and males, respectively. 15.18% of the subjects had elevated BP, with a significant difference according to gender detected only in the PAS z-score. Eating habits were investigated through a parent-filled questionnaire; 70.15% of the students consumed less than two portions of fruit per day, with a significant difference between gender (84.06% and 55.38% for boys and girls, respectively, p < 0.0001) and 71.64% ate less than two servings of vegetables per day. An alarming finding emerged for sweet snacks (30.6% of the students consumed 2-3 servings per day) and sugary drinks (2-3 servings per day for 32.84% of students) consumption. Our findings suggest that excess weight and hypertension in this population could be due to energy-rich, packaged-foods consumption. A nutrition education approach might thus help to reduce cardiovascular risk.


Assuntos
Dieta , Hipertensão , Masculino , Feminino , Humanos , Criança , Estudos Transversais , Maldivas , Comportamento Alimentar , Verduras , Estado Nutricional , Frutas , Inquéritos e Questionários , Hipertensão/epidemiologia
11.
Neurochem Res ; 36(5): 863-9, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21287268

RESUMO

We investigated whether the toxicity of oligomeric amyloid-beta peptide (Abeta1-42) upon differentiated human neuroblastoma SH-SY5Y cells, can be affected by changes of membrane lipid composition. An immunostaining technique, using lipids extracted from the cells and separated by thin layer chromatography, suggested that Abeta preferentially binds to phosphatidylethanolamine (PE), one of the major lipids in the cell extract. For this reason, we utilized treatments with putative inhibitors of phosphatidylethanolamine biosynthesis (choline, phosphocholine, R59949) to decrease its proportion in the cell membrane; choline treatment (2.5 mM, 24 h) showed the best performance, reducing phosphatidylethanolamine content from 5.7 to 3.3 µg phosphorous/mg protein. Either the extent of Abeta binding or its toxicity decreased onto choline-treated cells. These data may open the possibility to develop future strategies aiming to reduce Abeta toxicity in Alzheimer disease.


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Diferenciação Celular , Neuroblastoma/metabolismo , Fragmentos de Peptídeos/antagonistas & inibidores , Fosfatidiletanolaminas/metabolismo , Peptídeos beta-Amiloides/fisiologia , Linhagem Celular Tumoral , Cromatografia em Camada Fina , Humanos , Neuroblastoma/patologia , Fragmentos de Peptídeos/fisiologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-33801527

RESUMO

The strong spread of COVID-19 and the significant number of deaths associated with it could be related to improper lifestyles, which lead to a low-grade inflammation (LGI) that not only increases the risk of chronic diseases, but also the risk of facing complications relating to infections and a greater susceptibility to infections themselves. Recently, scientific research has widely demonstrated that the microbiota plays a fundamental role in modulating metabolic responses in the immune system. There is, in fact, a two-way interaction between lifestyle, infection, and immunity. The immune response is compromised if nutrition is unbalanced or insufficient, because diet affects the intestinal flora predisposing people to infections and, at the same time, the nutritional state can be aggravated by the immune response itself to the infection. We evaluate the link between balanced diet, the efficiency of the immune system, and microbiota with the aim of providing some practical advice for individuals, with special attention to the elderly. A correct lifestyle that follows the Mediterranean model, which is especially rich in plant-based foods along with the use of extra-virgin olive oil, are the basis of preventing LGI and other chronic pathologies, directly influencing the intestinal microbiota and consequently the immune response.


Assuntos
COVID-19 , Dieta Mediterrânea , Viroses , Idoso , Dieta , Humanos , Sistema Imunitário , Inflamação , Azeite de Oliva , SARS-CoV-2
13.
Artigo em Inglês | MEDLINE | ID: mdl-34299762

RESUMO

A balanced diet is a fundamental component of athletes' health, training, and performance. The majority of athletes choose adequate quantities of macronutrients but, at the same time, do not respect World Health Organization dietary guidelines, eating a lot of discretionary food and not drinking enough water. Athletes need more nutritional education to improve the quality of their food choice. By modifying their eating habits, they could also enhance their performance. Our study aimed to evaluate the impact of nutritional intervention on eating habits in a group of Northern Italian athletes. A sample of 87 athletes (41 males and 46 females) aged 16.5 ± 2.9 was enrolled. We organized meetings and detected eating habits (before and after the meetings) using a food frequencies questionnaire. We found that nutritional intervention positively affected participants consumption of vegetables (p < 0.05), nuts (p < 0.001), legumes (p < 0.001), and fish (p < 0.05). Other aspects of the athletes' eating habits were not significantly improved. Some gender differences were found; males increased their consumption of vegetables (p < 0.05) and nuts (p < 0.001), while females increased their intake of legumes (p < 0.001). Our finding suggested that nutritional intervention could promote healthy eating habits among athletes. If sports nutrition experts, coaches, personal trainers, sports medicine experts, and athletes cooperated, they could guarantee athletes' health status.


Assuntos
Ingestão de Energia , Comportamento Alimentar , Atletas , Dieta , Feminino , Preferências Alimentares , Humanos , Itália , Masculino
14.
Antioxidants (Basel) ; 10(8)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34439417

RESUMO

The contributing role of environmental factors to the development of neurodegenerative diseases has become increasingly evident. Here, we report that exposure of C6 glioma cells to diesel exhaust particles (DEPs), a major constituent of urban air pollution, causes intracellular reactive oxygen species (ROS) production. In this scenario, we suggest employing the possible protective role that coffee phenolic metabolites may have. Coffee is a commonly consumed hot beverage and a major contributor to the dietary intake of (poly) phenols. Taking into account physiological concentrations, we analysed the effects of two different coffee phenolic metabolites mixes consisting of compounds derived from bacterial metabolization reactions or phase II conjugations, as well as caffeic acid. The results showed that these mixes were able to counteract DEP-induced oxidative stress. The cellular components mediating the downregulation of ROS included extracellular signal-regulated kinase 1/2 (ERK1/2), nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and uncoupling protein 2 (UCP2). Contrary to coffee phenolic metabolites, the treatment with N-acetylcysteine (NAC), a known antioxidant, was found to be ineffective in preventing the DEP exposure oxidant effect. These results revealed that coffee phenolic metabolites could be promising candidates to protect against some adverse health effects of daily exposure to air pollution.

15.
Mol Cell Neurosci ; 42(1): 75-80, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19520166

RESUMO

We show that in hippocampal cultured neurons, dephosphorylation of peptidyl-prolyl cis-trans isomerase Pin1 on Ser16 is occurring during the early stages of exposure to Abeta (1-42) oligomers. This occurrence, resulting in Pin1 activation, is paralleled by Tau(Thr231) dephosphorylation, probably due to Pin1-mediated Tau isomerisation. Indeed, in the presence of the specific Pin1 inhibitor juglone, Abeta-induced Tau(Thr231)dephosphorylation is prevented. The involvement of protein phosphatase 2A (PP2A) in dephosphorylation of isomerised Tau is shown by the co-treatment of neurons with Abeta (1-42) and okadaic acid, a PP2A inhibitor, leading to Tau(Thr231) hyperphosphorylation. We also report the modulation, via Pin1, of Ser199, Ser396, Ser400 and Ser404 phosphorylation state in response to Abeta treatment. Taken together, these data suggest for the first time that an early Pin1 response might be transiently evoked by Abeta 1-42 oligomers, preventing Tau hyperphosphorylation. This evidence highlights the role of Pin1 as Tau phosphorylation modulator during Alzheimer onset.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Peptídeos beta-Amiloides/farmacologia , Neurônios/metabolismo , Fragmentos de Peptídeos/farmacologia , Proteínas tau/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citarabina/farmacologia , Embrião de Mamíferos , Inibidores Enzimáticos/farmacologia , Formazans , Hipocampo/citologia , Imunossupressores/farmacologia , Microscopia de Força Atômica/métodos , Naftoquinonas/farmacologia , Neurônios/efeitos dos fármacos , Ácido Okadáico/farmacologia , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Propanóis/farmacologia , Ratos , Sais de Tetrazólio , Fatores de Tempo
16.
Mol Cell Neurosci ; 40(3): 365-73, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19162192

RESUMO

Amyloid-beta (Abeta), a cytotoxic fragment of Amyloid Precursor Protein (APP), has been implicated in the etiopathogenesis of Alzheimer's disease (AD). Since several neurotrophins signalling pathways may be activated in response to toxic insults, we investigated whether a similar response is triggered also by Abeta. After Abeta (25-35) peptide administration to cultured rat hippocampal neurons, the nerve growth factor (NGF) and its receptor (TrkA) mRNA expression is up-regulated. Moreover, we observe an increased cellular TrkA expression (4.5 fold) and NGF release in the culture medium (5-fold). Concomitantly, TrkA, Akt and glycogen synthase kinase 3beta (Gsk3beta) phosphorylation significantly increase. Interestingly, when cells were treated with Abeta (25-35) in the presence of blocking antibody against NGF, only a partial TrkA activation (2-fold) was observed. These results have been confirmed by using pathophysiological Abeta (1-42) oligomers. Our data provide the evidence that Abeta induces the TrkA pathway activation directly by itself and indirectly promoting NGF secretion.


Assuntos
Peptídeos beta-Amiloides/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fragmentos de Peptídeos/farmacologia , Receptor trkA/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Caspases/metabolismo , Células Cultivadas , Ativação Enzimática , Hipocampo/citologia , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/metabolismo , Neurônios/citologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Receptor trkA/genética , Transdução de Sinais/fisiologia
17.
Hypertens Res ; 42(8): 1192-1199, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30923371

RESUMO

The aim of this study was to investigate the relationship between endothelin-1, nitric oxide, insulin resistance, and blood pressure in young subjects with a high prevalence of excess weight and/or elevated blood pressure. In a cohort of 238 children (mean age = 11.1 years), height, weight, waist circumference, and blood pressure were assessed. Body mass index, waist-to-height ratio, and blood pressure percentiles were calculated, and the children were classified as having excess weight and elevated blood pressure according to the International Obesity Task Force and the US blood pressure nomograms specific for gender, age and height, respectively. Endothelin-1 and nitric oxide production were assessed, and the homeostatic model assessment index was calculated. Forty-three percent of children were male, 71% had excess weight, and 37% had systolic and/or diastolic values above the ninetieth percentile. Plasma endothelin-1 and nitric oxide production were independently correlated (p < 0.05). In multivariate analyses, the HOMA index was associated with systolic and diastolic blood pressure (p = 0.01), and nitric oxide was independently related to diastolic blood pressure (p = 0.04), even after adjustment for measures of body composition. By using the waist-to-height ratio instead of BMI in the statistical model, the association between the homeostatic model assessment index and blood pressure was attenuated, while the results remained similar for nitric oxide. No correlation was found between endothelin-1 and blood pressure. In our study population, the correlation between nitric oxide and blood pressure and the lack of a relationship between endothelin-1 and blood pressure could be explained by an increase in the vasodilator effect of local and systemic nitric oxide, which counteracts the possible hypertensive effect of endothelin-1.


Assuntos
Pressão Sanguínea , Endotelina-1/sangue , Hipertensão/etiologia , Resistência à Insulina , Óxido Nítrico/sangue , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Hipertensão/sangue , Masculino , Sobrepeso/complicações
18.
Biochemistry ; 47(19): 5433-40, 2008 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-18416535

RESUMO

The influence of membrane lipid environment on the activity of GPI-anchored enzymes was investigated with human placental alkaline phosphatase reconstituted by a detergent-dialysis technique in liposomes composed of palmitoyloleoylphosphatidylcholine, alone or in mixture with lipids enriched along with the protein within lipid rafts: cholesterol, sphingomyelin, and GM1 ganglioside. The highest V max was recorded for a phosphatidylcholine/10% GM1 mixture (143 +/- 5 nmol of substrate hydrolyzed per minute per microgram of protein), while the lowest for a phosphatidylcholine/30% cholesterol mixture and for raft-mimicking 1:1:1 phosphatidylcholine/sphingolipid/cholesterol liposomes (M:M:M) (57 +/- 3 and 52 +/- 3, respectively). No significant differences in K m were detected. The protein segregation, assessed using the chemical cross-linker bis(sulfosuccinimidyl)suberate, increased with the protein:lipid ratio, within the 1:1200-1:4800 protein:lipid molar ratio range, but did not affect enzyme activity. The activity decreased when the order of the lipid bilayers was increased, higher for those containing cholesterol, as judged by steady-state fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene. Finally, the GPI-enzyme activity was affected by membrane curvature. This result was suggested by a strong inverse correlation (Pearson's correlation coefficient = 0.91; p < 0.0001) between activity and liposome diameter, measured by laser light scattering and ranging between 59 +/- 6 nm for a phosphatidylcholine/10% GM1 mixture (displaying the highest activity) and 188 +/- 25 nm for a phosphatidylcholine/30% cholesterol mixture and 185 +/- 23 nm for raft-mimicking liposomes (displaying the lowest activities). The activity-membrane curvature relationship was further confirmed by comparing the activity of proteoliposomes having different sizes but identical lipid compositions. These data open the possibility that the activity of GPI-anchored enzymes may be modulated by membrane microenvironment features, in particular by membrane curvature and cholesterol-enriched ordered microenvironments, such as those of lipid rafts.


Assuntos
Fosfatase Alcalina/metabolismo , Glicosilfosfatidilinositóis/química , Glicosilfosfatidilinositóis/metabolismo , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Modelos Biológicos , Fosfatase Alcalina/isolamento & purificação , Anisotropia , Humanos , Cinética , Lipossomos/metabolismo , Tamanho da Partícula , Placenta/enzimologia
19.
FEBS Lett ; 582(2): 215-20, 2008 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-18082145

RESUMO

Interaction of full length recombinant hamster prion protein with liposomes mimicking lipid rafts or non-raft membrane regions was studied by circular dichroism, chemical cross-linking and sucrose gradient ultracentrifugation. At pH 7.0, the protein bound palmitoyloleoylphosphatidylcholine/cholesterol/sphingomyelin/monosialoganglioside GM1 (GM1) ganglioside liposomes but not palmitoyloleoylphosphatidylcholine alone (bound/free=0.33 and 0.01, respectively), maintaining the native alpha-helical structure and monomeric form. At pH 5.0, though still binding to quaternary mixtures, in particular GM1, the protein bound also to palmitoyloleoylphosphatidylcholine (bound/free 0.35) becoming unfolded and oligomeric. The pH-dependent interaction with raft or non-raft membranes might have implication in vivo, by stabilizing or destabilizing the protein.


Assuntos
Concentração de Íons de Hidrogênio , Modelos Moleculares , Príons/química , Animais , Membrana Celular/metabolismo , Cricetinae , Lipossomos , Conformação Proteica , Proteínas Recombinantes/química
20.
Neurosci Lett ; 436(3): 317-20, 2008 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-18406523

RESUMO

We compared the levels of serum folate from Alzheimer's disease (AD) patients and from age-matched healthy subjects and used primary cultures of fibroblasts, obtained from the two groups, to assess possible differences in their ability to bind folate. The results show that the levels of circulating folate are significantly (p<0.01; n=30) lower in AD patients than in controls (4.91+/-2.44 and 7.56+/-2.5 ng/mL, respectively). Moreover, the folate binding of AD fibroblasts is significantly (p<0.01; n=8) higher (2-4-fold) with respect to controls. RT-PCR experiments suggest that the higher folate binding could be due to an enhanced expression in AD fibroblasts of folate receptor alpha.


Assuntos
Doença de Alzheimer/patologia , Proteínas de Transporte/metabolismo , Fibroblastos/metabolismo , Ácido Fólico/metabolismo , Receptores de Superfície Celular/metabolismo , Idoso , Idoso de 80 Anos ou mais , Proteínas de Transporte/genética , Células Cultivadas , Feminino , Fibroblastos/efeitos dos fármacos , Receptores de Folato com Âncoras de GPI , Regulação da Expressão Gênica/fisiologia , Humanos , Masculino , Entrevista Psiquiátrica Padronizada , RNA Mensageiro/metabolismo , Radioatividade , Receptores de Superfície Celular/genética
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