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1.
Eur J Nutr ; 63(1): 303-321, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37875637

RESUMO

BACKGROUND: Dietary nitrate (NO3-) has been shown to be useful as an ergogenic aid with potential applications in health and disease (e.g., blood pressure control). However, there is no consensus about the effects of dietary NO3- or beetroot (BR) juice supplementation on cognitive function. OBJECTIVE: The aim of this study was to evaluate the effects of a single dose of a chewable BR-based supplement on cognitive performance. METHODS: A double-blind randomized placebo-controlled two-period crossover clinical trial was carried out based on the extension of the CONSORT guidelines for randomized crossover trials. A total of 44 participants (24 F; 20 M; 32.7 [12.5] years; 66.3 [9.0] kg; 170 [9.2] cm; 22.8 [1.4] kg/m2) were randomly allocated to receive first either four BR-based chewable tablets (BR-CT) containing 3 g of a Beta vulgaris extract (RedNite®) or four tablets of a placebo (maltodextrin). A 4-day washout period was used before crossover. Ninety minutes after ingestion of the treatments, a neuropsychological testing battery was administered in each period. The trial was registered at clinicaltrials.gov NCT05509075. RESULTS: Significant improvements with moderate effect size were found on memory consolidation at the short and long term only after BR-CT supplementation via the Rey Auditory Verbal Learning Test immediate (+ 20.69%) and delayed (+ 12.34%) recalls. Likewise, enhancement on both frontal lobe functions (+ 2.57%) and cognitive flexibility (+ 11.16%) were detected after BR-CT. There was no significant change (p < 0.05) on verbal memory of short-term digits, working memory and information processing speed. Mixed results were found on mood and anxiety through the Beck Depression Inventory-II (BDI-II) and the State-Trait Anxiety Inventory (STAI-Y1 and STAI-Y2); however, sequence and period effects were seen on STAI-Y2. CONCLUSIONS: The acute administration of a chewable BR-based supplement improves certain aspects of cognitive function in healthy females and males, particularly memory capacity and frontal skills.


Assuntos
Beta vulgaris , Nitratos , Masculino , Feminino , Humanos , Estudos Cross-Over , Suplementos Nutricionais , Antioxidantes , Cognição , Método Duplo-Cego
2.
Int J Mol Sci ; 25(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38612567

RESUMO

Autophagy, a catabolic process orchestrating the degradation of proteins and organelles within lysosomes, is pivotal for maintaining cellular homeostasis. However, its dual role in cancer involves preventing malignant transformation while fostering progression and therapy resistance. Vacuole Membrane Protein 1 (VMP1) is an essential autophagic protein whose expression, per se, triggers autophagy, being present in the whole autophagic flux. In pancreatic cancer, VMP1-whose expression is linked to the Kirsten Rat Sarcoma Virus (KRAS) oncogene-significantly contributes to disease promotion, progression, and chemotherapy resistance. This investigation extends to breast cancer, colon cancer, hepatocellular carcinoma, and more, highlighting VMP1's nuanced nature, contingent on specific tissue contexts. The examination of VMP1's interactions with micro-ribonucleic acids (miRNAs), including miR-21, miR-210, and miR-124, enhances our understanding of its regulatory network in cancer. Additionally, this article discusses VMP1 gene fusions, especially with ribosomal protein S6 kinase B1 (RPS6KB1), shedding light on potential implications for tumor malignancy. By deciphering the molecular mechanisms linking VMP1 to cancer progression, this exploration paves the way for innovative therapeutic strategies to disrupt these pathways and potentially improve treatment outcomes.


Assuntos
Carcinoma Hepatocelular , Neoplasias do Colo , Neoplasias Hepáticas , Proteínas de Membrana , MicroRNAs , Humanos , Autofagia/genética , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , MicroRNAs/genética
3.
Neurol Sci ; 44(11): 3895-3903, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37354323

RESUMO

BACKGROUND: Previous literature has shown that executive functions (EF) are related to performance in memory (M) tasks. The Test of Memory strategies (TMS) is a psychometric test that examines EF and M simultaneously and it was recently validated on an Italian healthy cohort. The first aim of the study was to apply TMS, for the first time, on a sample of patients with Parkinson's disease (PD), who are characterized by mild cognitive impairment. The second aim is to investigate whether TMS scores can discriminate PD patients from healthy controls. METHOD: Ninety-eight subjects were enrolled, including 68 patients with PD, and 30 Italian healthy controls (HC), who also underwent a memory evaluation through well-known tests. RESULTS: Confirmatory factor analysis (CFA) demonstrated that TMS of PD patients had a bi-dimensional structure as previously found in healthy cohort. In detail, The TMS-1 and TMS-2 lists require greater involvement of the EF factor, while TMS-3, TMS-4 and TMS-5 the M factor. Receiver operating characteristic (ROC) curves and precision-recall (PR) curves showed that the M subscale can distinguish between HC and PD, while EF had poor discrimination power. CONCLUSION: The hypothesized prediction model of TMS test seems to have adequate ability to discriminate PD from HC especially for the M function.

4.
Int J Mol Sci ; 24(5)2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36902354

RESUMO

The coronavirus disease pandemic, which profoundly reshaped the world in 2019 (COVID-19), and is currently ongoing, has affected over 200 countries, caused over 500 million cumulative cases, and claimed the lives of over 6.4 million people worldwide as of August 2022. The causative agent is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Depicting this virus' life cycle and pathogenic mechanisms, as well as the cellular host factors and pathways involved during infection, has great relevance for the development of therapeutic strategies. Autophagy is a catabolic process that sequesters damaged cell organelles, proteins, and external invading microbes, and delivers them to the lysosomes for degradation. Autophagy would be involved in the entry, endo, and release, as well as the transcription and translation, of the viral particles in the host cell. Secretory autophagy would also be involved in developing the thrombotic immune-inflammatory syndrome seen in a significant number of COVID-19 patients that can lead to severe illness and even death. This review aims to review the main aspects that characterize the complex and not yet fully elucidated relationship between SARS-CoV-2 infection and autophagy. It briefly describes the key concepts regarding autophagy and mentions its pro- and antiviral roles, while also noting the reciprocal effect of viral infection in autophagic pathways and their clinical aspects.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Autofagia , Antivirais/farmacologia , Lisossomos/metabolismo
5.
Int J Mol Sci ; 24(16)2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37629161

RESUMO

Autophagy is a tightly regulated catabolic process involved in the degradation and recycling of proteins and organelles. Ubiquitination plays an important role in the regulation of autophagy. Vacuole Membrane Protein 1 (VMP1) is an essential autophagy protein. The expression of VMP1 in pancreatic cancer stem cells carrying the activated Kirsten rat sarcoma viral oncogene homolog (KRAS) triggers autophagy and enables therapy resistance. Using biochemical and cellular approaches, we identified ubiquitination as a post-translational modification of VMP1 from the initial steps in autophagosome biogenesis. VMP1 remains ubiquitinated as part of the autophagosome membrane throughout autophagic flux until autolysosome formation. However, VMP1 is not degraded by autophagy, nor by the ubiquitin-proteasomal system. Mass spectrometry and immunoprecipitation showed that the cell division cycle protein cdt2 (Cdt2), the substrate recognition subunit of the E3 ligase complex associated with cancer, cullin-RING ubiquitin ligase complex 4 (CRL4), is a novel interactor of VMP1 and is involved in VMP1 ubiquitination. VMP1 ubiquitination decreases under the CRL inhibitor MLN4924 and increases with Cdt2 overexpression. Moreover, VMP1 recruitment and autophagosome formation is significantly affected by CRL inhibition. Our results indicate that ubiquitination is a novel post-translational modification of VMP1 during autophagy in human tumor cells. VMP1 ubiquitination may be of clinical relevance in tumor-cell-therapy resistance.


Assuntos
Proteínas de Membrana , Neoplasias , Processamento de Proteína Pós-Traducional , Humanos , Autofagia/genética , Macroautofagia , Proteínas de Membrana/metabolismo , Ubiquitina , Ubiquitinação
6.
Arch Sex Behav ; 51(6): 2879-2889, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34791581

RESUMO

Previous studies have shown that olfactory function plays an essential role in the bonding of a romantic relationship. Body odors, in particular, seem involved in both mate choices and other intimate behaviors. Our sense of smell is also crucial to detect possible pathogen threats, by activating a suitable disgust reaction. Previous studies have shown that disgust sensitivity is negatively related to sociosexuality, and disgust generally inhibits our sexual drive. In the present study, we explored the possible relation between olfactory function, pathogen disgust sensitivity, sociosexuality, sexual well-being, and infidelity through a web survey. Our exploratory analyses found that, in a large Italian sample (N = 1107), among those in a stable relationship, self-reported olfactory function predicted sexual well-being (p < .05) and negatively predicted infidelity (p < .05) when controlling for other relevant sociodemographics variables. Moreover, the relation between self-reported olfactory function and sexual well-being was mediated by pathogen disgust sensitivity. Although significant, these results must be interpreted with caution, because the effect sizes were small.


Assuntos
Odorantes , Comportamento Sexual , Humanos , Autorrelato , Parceiros Sexuais , Olfato
7.
Neurol Sci ; 43(1): 643-650, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33931819

RESUMO

Deep grey nuclei of the human brain accumulate minerals both in aging and in several neurodegenerative diseases. Mineral deposition produces a shortening of the transverse relaxation time which causes hypointensity on magnetic resonance (MR) imaging. The physician often has difficulties in determining whether the incidental hypointensity of grey nuclei seen on MR images is related to aging or neurodegenerative pathology. We investigated the hypointensity patterns in globus pallidus, putamen, caudate nucleus, thalamus and dentate nucleus of 217 healthy subjects (ages, 20-79 years; men/women, 104/113) using 3T MR imaging. Hypointensity was detected more frequently in globus pallidus (35.5%) than in dentate nucleus (32.7%) and putamen (7.8%). A consistent effect of aging on hypointensity (p < 0.001) of these grey nuclei was evident. Putaminal hypointensity appeared only in elderly subjects whereas we did not find hypointensity in the caudate nucleus and thalamus of any subject. In conclusion, the evidence of hypointensity in the caudate nucleus and thalamus at any age or hypointensity in the putamen seen in young subjects should prompt the clinician to consider a neurodegenerative disease.


Assuntos
Doenças Neurodegenerativas , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Feminino , Substância Cinzenta , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doenças Neurodegenerativas/diagnóstico por imagem , Putamen/diagnóstico por imagem , Adulto Jovem
8.
EMBO J ; 36(14): 2018-2033, 2017 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-28550152

RESUMO

The double-membrane-bound autophagosome is formed by the closure of a structure called the phagophore, origin of which is still unclear. The endoplasmic reticulum (ER) is clearly implicated in autophagosome biogenesis due to the presence of the omegasome subdomain positive for DFCP1, a phosphatidyl-inositol-3-phosphate (PI3P) binding protein. Contribution of other membrane sources, like the plasma membrane (PM), is still difficult to integrate in a global picture. Here we show that ER-plasma membrane contact sites are mobilized for autophagosome biogenesis, by direct implication of the tethering extended synaptotagmins (E-Syts) proteins. Imaging data revealed that early autophagic markers are recruited to E-Syt-containing domains during autophagy and that inhibition of E-Syts expression leads to a reduction in autophagosome biogenesis. Furthermore, we demonstrate that E-Syts are essential for autophagy-associated PI3P synthesis at the cortical ER membrane via the recruitment of VMP1, the stabilizing ER partner of the PI3KC3 complex. These results highlight the contribution of ER-plasma membrane tethers to autophagosome biogenesis regulation and support the importance of membrane contact sites in autophagy.


Assuntos
Autofagossomos/metabolismo , Membrana Celular/metabolismo , Retículo Endoplasmático/metabolismo , Biogênese de Organelas , Fosfatos de Fosfatidilinositol/metabolismo , Animais , Proteínas de Transporte/metabolismo , Cães , Células HeLa , Humanos , Células Madin Darby de Rim Canino , Proteínas de Membrana/metabolismo , Sinaptotagminas/metabolismo
9.
World J Surg ; 45(1): 252-260, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33063199

RESUMO

BACKGROUND: Laparoscopic distal pancreatectomy (LDP) represents a challenging procedure with a high conversion rate. A nomogram is a simple statistical predictive tool which is superior to risk groups. The aim of this study was to develop and validate a preoperative nomogram for predicting the probability of conversion from laparoscopic to open distal pancreatectomy. METHODS: This is a retrospective study of 100 consecutive patients who underwent LDP. For each patient demographic, pre-intra- and postoperative data were collected. Univariate and multivariate analyses were carried out to identify the factors significantly influencing the conversion rate. The effect of each factor was weighted using the beta coefficient (ß), and a nomogram was built. Finally, a logistic regression between the score and the conversion rate was carried out to calibrate the nomogram. RESULTS: The conversion rate was 19.0%. At multivariate analysis, female (ß = - 1.8 ± 0.9; P = 0.047) and tail location of the tumor (ß = - 2.1 ± 1.1; P = 0.050) were significantly related to a low probability of conversion. Body mass index (BMI) (ß = 0.2 ± 0.1; P = 0.011) and subtotal pancreatectomy (ß = 2.4 ± 0.9; P = 0.006) were factors independently related to a high probability of conversion. The nomogram constructed had a minimum value of 4 and a maximum value of 18 points. The probability of conversion increased significantly starting from a minimum score of 6 points (P = 0.029; conversion probability 14.4%; 95%CI, 1.5-27.3%) up to 16 (P = 0.048; 27.8%; 95%CI, 0.2-48.7%). CONCLUSION: The nomogram proposed could serve as an effective preoperative tool capable of assessing the probability of conversion, allowing to take reliable decisions regarding indications and adequate stepwise training program of LDP.


Assuntos
Laparoscopia , Idoso , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Nomogramas , Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Complicações Pós-Operatórias , Estudos Retrospectivos , Resultado do Tratamento
10.
Psychiatr Danub ; 33(Suppl 9): 169-171, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34559798

RESUMO

The COVID-19 outbreak has dramatically impacted on socioeconomic structure, individual freedom, general wellbeing, psychological health and sexuality. Indeed, social distancing, home confinement and the fear of contagion have reduced the possibility of romantic encounters thus influencing sexual activity, desire and behavior and, consequently, modifying socio-sexual experiences. The aim of this study is to examine sociosexuality and sociosexual experiences in southern Italians during the COVID-19 pandemic.


Assuntos
COVID-19 , Pandemias , Análise por Conglomerados , Humanos , Itália/epidemiologia , SARS-CoV-2 , Comportamento Sexual
11.
Epilepsy Behav ; 97: 8-14, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31181431

RESUMO

Déjà vu (DV) is a fascinating and mysterious human experience that has attracted interest from psychologists and neuroscientists for over a century. In recent years, several studies have been conducted to unravel the psychological and neurological correlates of this phenomenon. However, the neural mechanisms underlying the DV experience in benign manifestations are still poorly understood. Thirty-three healthy volunteers completed an extensive neuropsychiatric and neuropsychological battery including personality evaluation. The presence of DV was assessed with the Inventory for Deja vu Experiences Assessment. Participants underwent episodic memory learning test, and 2 days later during event-related functional magnetic resonance imaging (fMRI), they are asked to rate old and new pictures as a novel, moderately/very familiar, or recollected. We identified 18 subjects with DV (DV+) and 15 without DV (DV-) matched for demographical, neuropsychological, and personality characteristics. At a behavioral level, no significant difference was detected in the episodic memory tasks between DV+ and DV-. Functional magnetic resonance imaging analysis revealed that DV+, independently from task conditions, were characterized by increased activity of the bilateral insula coupled with reduced activation in the right parahippocampal, both hippocampi, superior/middle temporal gyri, thalami, caudate nuclei, and superior frontal gyri with respect to DV-. Our study demonstrates that individuals who experienced DV are not characterized by different performance underlying familiarity/recollection memory processes. However, fMRI results provide evidence that the physiological DV experience is associated with the employment of different neural responses of brain regions involved in memory and emotional processes.


Assuntos
Encéfalo/fisiopatologia , Déjà Vu , Emoções/fisiologia , Memória Episódica , Memória/fisiologia , Adulto , Mapeamento Encefálico/métodos , Cognição/fisiologia , Déjà Vu/psicologia , Feminino , Hipocampo/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Rememoração Mental , Córtex Pré-Frontal/fisiologia , Lobo Temporal/fisiopatologia
12.
Bioorg Med Chem ; 26(14): 3953-3957, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-29934219

RESUMO

The natural product magnolol (1) and a selection of its bioinspired derivatives 2-5, were investigated by Inverse Virtual Screening in order to identify putative biological targets from a panel of 308 proteins involved in cancer processes. By this in silico analysis we selected tankyrase-2 (TNKS2), casein kinase 2 (CK2) and bromodomain 9 (Brd9) as potential targets for experimental evaluations. The Surface Plasmon Resonance assay revealed that 3-5 present a good affinity for tankyrase-2, and, in particular, 3 showed an antiproliferative activity on A549 cells higher than the well-known tankyrase-2 inhibitor XAV939 used as reference compound.


Assuntos
Antineoplásicos/farmacologia , Compostos de Bifenilo/farmacologia , Lignanas/farmacologia , Tanquirases/antagonistas & inibidores , Algoritmos , Antineoplásicos/síntese química , Antineoplásicos/química , Compostos de Bifenilo/síntese química , Compostos de Bifenilo/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lignanas/síntese química , Lignanas/química , Estrutura Molecular , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade , Ressonância de Plasmônio de Superfície , Tanquirases/metabolismo , Termodinâmica , Células Tumorais Cultivadas
13.
Epilepsy Behav ; 85: 222-226, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30032811

RESUMO

OBJECTIVE: In the current literature, whether patients with mild mesial temporal lobe epilepsy (mMTLE) have typical neurocognitive profile similar to patients with treatment-refractory seizures still remains unknown. The purpose of the present work was to analyze the neuropsychological profile in a group of consecutive patients with mMTLE. METHODS: Forty consecutive patients whose conditions were diagnosed with mMTLE and 30 healthy controls (HC) were evaluated with an extensive neuropsychological battery. In addition, self-report questionnaires were also administered to evaluate the subjective impairments in prospective and retrospective memories. Finally, the levels of depression and anxiety were evaluated using the Beck Depression Inventory II (BDI-II) and the State-Trait Anxiety Inventory - Form Y1 (STAI-YI e 2). RESULTS: Patients with mMTLE patients showed higher BDI-II scores (15.9 ±â€¯13.9 vs 7.2 ±â€¯6.7; p =, 002), and higher STAI-Y1 (41.2 ±â€¯14.6 vs 32.6 ± 9.8; p =, 005) together with both objective and subjective memory deficits. Although BDI-II and STAI scores strongly correlated to the outcome in Rey Auditory Verbal Learning Test (RAVLT) and prospective and retrospective memory questionnaire (PRMQ) (p < 0.0021), these results did not change without depression scores. CONCLUSION: We showed that a specific neurocognitive profile in patients with mMTLE exists. The neuropsychological features are mood depression, verbal memory immediate and delayed deficits, and subjective prospective and retrospective memory deficits.


Assuntos
Epilepsia do Lobo Temporal/diagnóstico , Epilepsia do Lobo Temporal/psicologia , Memória Episódica , Testes Neuropsicológicos , Adulto , Ansiedade/diagnóstico , Ansiedade/epidemiologia , Ansiedade/psicologia , Depressão/diagnóstico , Depressão/epidemiologia , Depressão/psicologia , Epilepsia do Lobo Temporal/epidemiologia , Feminino , Humanos , Masculino , Transtornos da Memória/diagnóstico , Transtornos da Memória/epidemiologia , Transtornos da Memória/psicologia , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Autorrelato , Inquéritos e Questionários
14.
J Nat Prod ; 81(8): 1786-1794, 2018 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-30063349

RESUMO

Two new glucopyranosylbianthrones (1 and 2) were isolated from the aerial part of the plant Asphodelus tenuifolius, collected in Southwest Algeria. The 2D structures of 1 and 2 were defined by NMR analysis, HRESIMS data, and comparison with literature data. The comparison of experimental and calculated electronic circular dichroism and NMR data led to characterization of the ( M) and ( P) atropisomeric forms of the glucopyranosylbianthrones, asphodelins (1) and (2), respectively. The in vitro activities of these two metabolites were evaluated in human melanoma A375 cells, and both the compounds inhibited cell proliferation in a concentration-dependent manner, with IC50 values of 20.6 ± 0.8 and 23.2 ± 1.1 µM, respectively. Considering their biological profile, an inverse virtual screening approach was employed to identify and suggest putative anticancer interacting targets.


Assuntos
Antracenos/química , Antracenos/farmacologia , Liliaceae/química , Argélia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Simulação por Computador , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade
15.
Clin Sci (Lond) ; 131(8): 673-687, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28188238

RESUMO

The aim of the present study was to demonstrate the role of autophagy and incretins in the fructose-induced alteration of ß-cell mass and function. Normal Wistar rats were fed (3 weeks) with a commercial diet without (C) or with 10% fructose in drinking water (F) alone or plus sitagliptin (CS and FS) or exendin-4 (CE and FE). Serum levels of metabolic/endocrine parameters, ß-cell mass, morphology/ultrastructure and apoptosis, vacuole membrane protein 1 (VMP1) expression and glucose-stimulated insulin secretion (GSIS) were studied. Complementary to this, islets isolated from normal rats were cultured (3 days) without (C) or with F and F + exendin-4 or chloroquine. Expression of autophagy-related proteins [VMP1 and microtubule-associated protein light chain 3 (LC3)], apoptotic/antiapoptotic markers (caspase-3 and Bcl-2), GSIS and insulin mRNA levels were measured. F rats developed impaired glucose tolerance (IGT) and a significant increase in plasma triacylglycerols, thiobarbituric acid-reactive substances, insulin levels, homoeostasis model assessment (HOMA) for insulin resistance (HOMA-IR) and ß-cell function (HOMA-ß) indices. A significant reduction in ß-cell mass was associated with an increased apoptotic rate and morphological/ultrastructural changes indicative of autophagic activity. All these changes were prevented by either sitagliptin or exendin-4. In cultured islets, F significantly enhanced insulin mRNA and GSIS, decreased Bcl-2 mRNA levels and increased caspase-3 expression. Chloroquine reduced these changes, suggesting the participation of autophagy in this process. Indeed, F induced the increase of both VMP1 expression and LC3-II, suggesting that VMP1-related autophagy is activated in injured ß-cells. Exendin-4 prevented islet-cell damage and autophagy development. VMP1-related autophagy is a reactive process against F-induced islet dysfunction, being prevented by exendin-4 treatment. This knowledge could help in the use of autophagy as a potential target for preventing progression from IGT to type 2 diabetes mellitus.


Assuntos
Autofagia/efeitos dos fármacos , Dieta/efeitos adversos , Frutose/farmacologia , Incretinas/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Proteínas de Membrana/fisiologia , Animais , Autofagia/fisiologia , Peso Corporal , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos/métodos , Ingestão de Energia , Exenatida , Frutose/administração & dosagem , Intolerância à Glucose/etiologia , Intolerância à Glucose/patologia , Intolerância à Glucose/prevenção & controle , Teste de Tolerância a Glucose , Hipoglicemiantes/farmacologia , Insulina/biossíntese , Insulina/genética , Células Secretoras de Insulina/ultraestrutura , Masculino , Microscopia Eletrônica , Peptídeos/farmacologia , RNA Mensageiro/genética , Ratos Wistar , Fosfato de Sitagliptina/farmacologia , Peçonhas/farmacologia
16.
J Org Chem ; 82(17): 8848-8863, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28763612

RESUMO

Cyclic peptoids have recently emerged as important examples of peptidomimetics for their interesting complexing properties and innate ability to permeate biological barriers. In the present contribution, experimental and theoretical data evidence the intricate conformational and stereochemical properties of five novel hexameric peptoids decorated with N-isopropyl, N-isobutyl, and N-benzyl substituents. Complexation studies by NMR, in the presence of sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate (NaTFPB), theoretical calculations, and single-crystal X-ray analyses indicate that the conformationally stable host/guest metal adducts display architectural ordering comparable to that of the enniatins and beauvericin mycotoxins. Similarly to the natural depsipeptides, the synthetic oligolactam analogues show a correlation between ion transport abilities in artificial liposomes and cytotoxic activity on human cancer cell lines. The reported results demonstrate that the versatile cyclic peptoid scaffold, for its remarkable conformational and complexing properties, can morphologically mimic related natural products and elicit powerful biological activities.


Assuntos
Micotoxinas/farmacologia , Peptidomiméticos/farmacologia , Peptoides/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Humanos , Modelos Moleculares , Micotoxinas/síntese química , Micotoxinas/química , Peptidomiméticos/síntese química , Peptidomiméticos/química , Peptoides/síntese química , Peptoides/química , Conformação Proteica , Teoria Quântica , Relação Estrutura-Atividade
17.
Chemistry ; 22(37): 13236-50, 2016 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-27492719

RESUMO

The identification of inhibitors of Hsp90 is currently a primary goal in the development of more effective drugs for the treatment of various types of multidrug resistant malignancies. In an attempt to identify new small molecules modulating the activity of Hsp90, we screened a small library of tetranortriterpenes. A high-affinity interaction with Hsp90 inducible form was uncovered for eight of these compounds, five of which are described here for the first time. By monitoring the ATPase activity and the citrate synthase thermal induced aggregation, compound 1 (cedrelosin A), 3 (7α-limonylacetate), and 5 (cedrelosin B), containing a limonol moiety, were found to be the most effective in compromising the Hsp90α chaperone activity. Consistent with these findings, the three compounds caused a depletion of c-Raf and pAkt Hsp90 client proteins in HeLa and MCF/7 cell lines. Induced fit docking protocol and molecular dynamics were used to rationalize the structural basis of the biological activity of the limonol derivatives. Taken together, these results point to limonol-derivatives as promising scaffolds for the design of novel Hsp90α inhibitors.


Assuntos
Antineoplásicos/química , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Extratos Vegetais/química , Triterpenos/química , Adenosina Trifosfatases/metabolismo , Antineoplásicos/farmacologia , Sítios de Ligação , Sobrevivência Celular , Chromolaena/química , Citrato (si)-Sintase/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Células HeLa , Humanos , Células MCF-7 , Simulação de Acoplamento Molecular , Folhas de Planta/química , Ligação Proteica , Conformação Proteica , Dobramento de Proteína , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Triterpenos/farmacologia
19.
Zygote ; 23(5): 669-82, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25230050

RESUMO

Actin-based cytoskeleton (CSK) and microtubules may bind to RNAs and related molecules implicated in translation. However, many questions remain to be answered regarding the role of cytoskeletal components in supporting the proteins involved in steps in the maturation and translation processes. Here, we performed co-immunoprecipitation and immunofluorescence to examine the association between spectrins, keratins and tubulin and proteins involved in 60S ribosomal maturation and translation in Xenopus stage I oocytes, including ribosomal rpl10, eukaryotic initiation factor 6 (Eif6), thesaurins A/B, homologs of the eEF1α elongation factor, and P0, the ribosomal stalk protein. We found that rpl10 and eif6 cross-reacted with the actin-based CSK and with tubulin. rpl10 co-localizes with spectrin, particularly in the perinuclear region. eif6 is similarly localized. Given that upon ribosomal maturation, the insertion of rpl10 into the 60S subunit occurs simultaneously with the release of eif6, one can hypothesise that actin-based CSK and microtubules provide the necessary scaffold for the insertion/release of these two molecules and, subsequently, for eif6 transport and binding to the mature 60S subunit. P0 and thesaurins cross-reacted with only spectrin and cytokeratins. Thesaurins aggregated at the oocyte periphery, rendering this a territory favourable site for protein synthesis; the CSK may support the interaction between thesaurins and sites of the translating ribosome. Moreover, given that the assembly of the ribosome stalk, where P0 is located, to the 60S subunit is essential for the release of eif6, it can be hypothesised that the CSK can facilitate the binding of the stalk to the 60S.


Assuntos
Citoesqueleto de Actina/metabolismo , Proteínas do Citoesqueleto/metabolismo , Oócitos/metabolismo , Proteínas Ribossômicas/metabolismo , Ribossomos/fisiologia , Proteínas de Xenopus/metabolismo , Xenopus laevis/metabolismo , Animais , Western Blotting , Imunofluorescência , Imunoprecipitação , Xenopus laevis/crescimento & desenvolvimento
20.
Front Neurol ; 15: 1372262, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38585347

RESUMO

Objective: To investigate the performance of structural MRI cortical and subcortical morphometric data combined with blink-reflex recovery cycle (BRrc) values using machine learning (ML) models in distinguishing between essential tremor (ET) with resting tremor (rET) and classic ET. Methods: We enrolled 47 ET, 43 rET patients and 45 healthy controls (HC). All participants underwent brain 3 T-MRI and BRrc examination at different interstimulus intervals (ISIs, 100-300 msec). MRI data (cortical thickness, volumes, surface area, roughness, mean curvature and subcortical volumes) were extracted using Freesurfer on T1-weighted images. We employed two decision tree-based ML classification algorithms (eXtreme Gradient Boosting [XGBoost] and Random Forest) combining MRI data and BRrc values to differentiate between rET and ET patients. Results: ML models based exclusively on MRI features reached acceptable performance (AUC: 0.85-0.86) in differentiating rET from ET patients and from HC. Similar performances were obtained by ML models based on BRrc data (AUC: 0.81-0.82 in rET vs. ET and AUC: 0.88-0.89 in rET vs. HC). ML models combining imaging data (cortical thickness, surface, roughness, and mean curvature) together with BRrc values showed the highest classification performance in distinguishing between rET and ET patients, reaching AUC of 0.94 ± 0.05. The improvement in classification performances when BRrc data were added to imaging features was confirmed by both ML algorithms. Conclusion: This study highlights the usefulness of adding a simple electrophysiological assessment such as BRrc to MRI cortical morphometric features for accurately distinguishing rET from ET patients, paving the way for a better classification of these ET syndromes.

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