RESUMO
Scorpion venoms have proven to be excellent sources of antimicrobial agents. However, although many of them have been functionally characterized, they remain underutilized as pharmacological agents, despite their evident therapeutic potential. In this review, we discuss the physicochemical properties of short scorpion venom antimicrobial peptides (ssAMPs). Being generally short (13-25 aa) and amidated, their proven antimicrobial activity is generally explained by parameters such as their net charge, the hydrophobic moment, or the degree of helicity. However, for a complete understanding of their biological activities, also considering the properties of the target membranes is of great relevance. Here, with an extensive analysis of the physicochemical, structural, and thermodynamic parameters associated with these biomolecules, we propose a theoretical framework for the rational design of new antimicrobial drugs. Through a comparison of these physicochemical properties with the bioactivity of ssAMPs in pathogenic bacteria such as Staphylococcus aureus or Acinetobacter baumannii, it is evident that in addition to the net charge, the hydrophobic moment, electrostatic energy, or intrinsic flexibility are determining parameters to understand their performance. Although the correlation between these parameters is very complex, the consensus of our analysis suggests that there is a delicate balance between them and that modifying one affects the rest. Understanding the contribution of lipid composition to their bioactivities is also underestimated, which suggests that for each peptide, there is a physiological context to consider for the rational design of new drugs.
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Peptídeos Antimicrobianos , Venenos de Escorpião , Venenos de Escorpião/química , Venenos de Escorpião/farmacologia , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/farmacologia , Animais , Humanos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Interações Hidrofóbicas e Hidrofílicas , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , TermodinâmicaRESUMO
OBJECTIVE: This study was undertaken to study pareidolias, or perceived meaningful objects in a meaningless stimulus, in patients across the Lewy body (LB) disease spectrum, where most do not report hallucinations or delusions. METHODS: We studied illusory responses on the Noise Pareidolia Task in 300 participants (38 cognitively impaired LB, 65 cognitively unimpaired LB, 51 Alzheimer disease spectrum [AD-s], 146 controls). Pairwise between-group comparisons examined how diagnosis impacts the number of illusory responses. Ordinal regression analysis compared the number of illusory responses across diagnosis groups, adjusting for age, sex, and education. Analyses were repeated after removing participants with reported hallucinations or delusions. RESULTS: Cognitively impaired LB participants were 12.3, 4.9, and 4.6 times more likely than control, cognitively unimpaired LB, and AD-s participants, respectively, to endorse illusory responses. After adjusting for age, sex, and education, the probability of endorsing 1 or more illusory responses was 61% in the cognitively impaired LB group, compared to 26% in AD-s, 25% in cognitively unimpaired LB, and 12% in control participants. All results were similar after repeated analysis only in participants without hallucinations or delusions. In LB without hallucinations or delusions, 52% with mild cognitive impairment and 66.7% with dementia endorsed at least 1 illusory response. INTERPRETATION: We found illusory responses are common in cognitively impaired LB patients, including those without any reported psychosis. Our data suggest that, prior to the onset of hallucinations and delusions, the Noise Pareidolia Task can easily be used to screen for unobtrusive pareidolias in all LB patients. ANN NEUROL 2023;93:702-714.
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Doença de Alzheimer , Disfunção Cognitiva , Ilusões , Doença por Corpos de Lewy , Humanos , Doença por Corpos de Lewy/psicologia , Doença de Alzheimer/psicologia , AlucinaçõesRESUMO
Fucosyltransferases (Fut) regulate the fucosylation process associated with tumorogenesis in different cancer types. Ascitic fluid (AF) from patients diagnosed with advanced stage of epithelial ovarian cancer (EOC) is considered as a dynamic tumor microenvironment associated with poor prognosis. Previous studies from our laboratory showed increased fucosylation in SKOV-3 and OVCAR-3, cancer-derived cell lines, when these cells were incubated with AFs derived from patients diagnosed with EOC. In the present work we studied three fucosyltransferases (Fut 2, Fut 4, and Fut 8) in SKOV-3, OVCAR-3 and CAOV-3 cell lines in combination with five different AFs from patients diagnosed with this disease, confirming that all tested AFs increased fucosylation. Then, we demonstrate that mRNAs of these three enzymes were overexpressed in the three cell lines under treatment with AFs. SKOV-3 showed the higher overexpression of Fut 2, Fut 4, and Fut 8 in comparison with the control condition. We further confirmed, in the SKOV-3 cell line, by endpoint PCR, WB, and confocal microscopy, that the three enzymes were overexpressed, being Fut 4 the most overexpressed enzyme compared to Fut 2 and Fut 8. These enzymes were concentrated in vesicular structures with a homogeneous distribution pattern throughout the cytoplasm. Moreover, we found that among the three enzymes, only Fut 4 was located inside the nuclei. The nuclear location of Fut 4 was confirmed for the three cell lines. These results allow to propose Fut 2, Fut 4, and Fut 8 as potential targets for EOC treatment or as diagnostic tools for this disease.
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Neoplasias Ovarianas , Humanos , Feminino , Neoplasias Ovarianas/metabolismo , Carcinoma Epitelial do Ovário , Líquido Ascítico/metabolismo , Líquido Ascítico/patologia , Galactosídeo 2-alfa-L-Fucosiltransferase , Apoptose , Linhagem Celular Tumoral , Fucosiltransferases/genética , Fucosiltransferases/metabolismo , Microambiente TumoralRESUMO
INTRODUCTION: Clinical research in Alzheimer's disease (AD) lacks cohort diversity despite being a global health crisis. The Asian Cohort for Alzheimer's Disease (ACAD) was formed to address underrepresentation of Asians in research, and limited understanding of how genetics and non-genetic/lifestyle factors impact this multi-ethnic population. METHODS: The ACAD started fully recruiting in October 2021 with one central coordination site, eight recruitment sites, and two analysis sites. We developed a comprehensive study protocol for outreach and recruitment, an extensive data collection packet, and a centralized data management system, in English, Chinese, Korean, and Vietnamese. RESULTS: ACAD has recruited 606 participants with an additional 900 expressing interest in enrollment since program inception. DISCUSSION: ACAD's traction indicates the feasibility of recruiting Asians for clinical research to enhance understanding of AD risk factors. ACAD will recruit > 5000 participants to identify genetic and non-genetic/lifestyle AD risk factors, establish blood biomarker levels for AD diagnosis, and facilitate clinical trial readiness. HIGHLIGHTS: The Asian Cohort for Alzheimer's Disease (ACAD) promotes awareness of under-investment in clinical research for Asians. We are recruiting Asian Americans and Canadians for novel insights into Alzheimer's disease. We describe culturally appropriate recruitment strategies and data collection protocol. ACAD addresses challenges of recruitment from heterogeneous Asian subcommunities. We aim to implement a successful recruitment program that enrolls across three Asian subcommunities.
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Doença de Alzheimer , População Norte-Americana , Humanos , Doença de Alzheimer/genética , Projetos Piloto , Asiático/genética , Canadá , Fatores de RiscoRESUMO
In Leishmania mexicana, the protease gp63 has been documented as the protein responsible for cyclooxygenase (COX) activity. The present work aimed to obtain a monoclonal antibody capable of recognizing this protein without blocking the COX-like enzymatic activity. The antibody produced by the selected hybridoma was named D12 mAb. The antigen recognized by the D12 mAb was characterized by the determination of COX activity associated with immune complexes in the presence of exogenous arachidonic acid (AA) using the commercial Activity Assay Abcam kit. LSM-SMS analysis validated the identity of the antigen associated with the D12 mAb as the L. mexicana protease gp63. Confocal microscopy assays with the D12 mAb detected, by cross-recognition, similar proteins in other protozoan parasites. COX-like molecules are located in vesicular structures, homogeneously distributed throughout the cytoplasm in amastigotes (intracellular infectious phase) and promastigotes of L. mexicana, and trophozoites of Entamoeba histolytica, Acanthamoeba castellanii, and Naegleria fowleri. However, in Giardia duodenalis trophozoites, the distribution of the COX-like molecule was also in perinuclear areas. In comparison, in Trypanosoma cruzi trypomastigotes, the distribution was mainly observed in the plasma membrane. Structural analyses of COX-2-like antigens revealed continuous and discontinuous epitopes for B cells, which could be relevant in the cross-reaction of D12 mAb with the analyzed parasites. These results indicate that the D12 mAb against the L. mexicana gp63 also recognizes a COX-like molecule in several protozoan parasites, suggesting that this D12 mAb could potentially be used in combined therapies against infectious diseases.
Assuntos
Anticorpos Monoclonais , Leishmania mexicana , Ciclo-Oxigenase 2 , Relevância Clínica , Antígenos de Protozoários , Peptídeo HidrolasesRESUMO
BACKGROUND: Ovarian cancer is the most aggressive gynecological malignancy. Transcriptional regulators impact the tumor phenotype and, consequently, clinical progression and response to therapy. PHD finger protein 20-like protein 1 (PHF20L1) is a transcriptional regulator with several isoforms, and studies on its role in ovarian cancer are limited. We previously reported that PHF20L1 is expressed as a fucosylated protein in SKOV-3 cells stimulated with ascites from patients with ovarian cancer. METHODS: We decided to analyze the expression of PHF20L1 in ovarian cancer tissues, determine whether a correlation exists between PHF20L1 expression and patient clinical data, and analyze whether ascites can modulate the different isoforms of this protein. Ovarian cancer biopsies from 29 different patients were analyzed by immunohistochemistry, and the expression of the isoforms in ovarian cancer cells with or without exposure to the tumor microenvironment, i.e., the ascitic fluid, was determined by western blotting assays. RESULTS: Immunohistochemical results suggest that PHF20L1 exhibits increased expression in sections of tumor tissues from patients with ovarian cancer and that higher PHF20L1 expression correlates with shorter progression-free survival and shorter overall survival. Furthermore, western blotting assays determined that protein isoforms are differentially regulated in SKOV-3 cells in response to stimulation with ascites from patients with epithelial ovarian cancer. CONCLUSION: The results suggest that PHF20L1 could play a relevant role in ovarian cancer given that higher PHF20L1 protein expression is associated with lower overall patient survival.
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AIM: The genus Fusarium comprises plant pathogenic species with agricultural relevance. Fusarium oxysporum causes tomato wilt disease with significant production losses. The use of agrochemicals to control the Fusarium wilt of tomato is not environmentally friendly. Bacillus species, as biocontrol agents, provide a safe and sustainable means to control Fusarium-induced plant diseases. In this study, the ability of Bacillus cereus MH778713, a strain isolated from root nodules of Prosopis laevigata, to protect tomato plants against Fusarium wilt was evaluated. METHODS AND RESULTS: Bacillus cereus MH778713 and its volatiles inhibited the radial growth of F. oxysporum and stimulated tomato seedling growth in in vitro and in vivo tests. When tomato plants growing in the greenhouse were inoculated with B. cereus MH778713, the percentage of wilted plants decreased from 96% to 12%, indicating an effective crop protection against Fusarium wilt. Among the metabolites produced by B. cereus MH778713, hentriacontane and 2,4-di-tert-butylphenol promoted tomato seedling growth and showed antifungal activity against the target pathogen. CONCLUSION: The inoculation of B. cereus MH778713 on tomato seedlings helped plants to manage Fusarium wilt, suggesting the potential of B. cereus MH778713 as a biocontrol agent. SIGNIFICANCE AND IMPACT OF THE STUDY: These results complement our previous studies on chromium tolerance and bioremediation traits of B. cereus MH778713 by highlighting the potential of this metal-resistant micro-organism to boost crop growth and disease resistance.
Assuntos
Bacillus cereus/fisiologia , Agentes de Controle Biológico , Fusarium , Doenças das Plantas/prevenção & controle , Solanum lycopersicum , Fusarium/patogenicidade , Solanum lycopersicum/microbiologia , Doenças das Plantas/microbiologiaRESUMO
Emotions are essential processes for integrating events into autobiographical memory. Different children react differently to the same event. The process through which these different responses are generated from subjective evaluations of an event is called emotional appraisal. The main purpose of this study was to analyze the variations in the emotional appraisal of autobiographical events of 4- and 5-year-old children from homes with different socioenvironmental conditions. We compared preschoolers' emotional appraisal responses with those of their families. The emotional accuracy of the preschoolers was found to differ according to the different socioenvironmental conditions of their homes. Greater appraisal accuracy was observed in the favorable condition, and it was greater for emotional events than for neutral events. Appraisal accuracy also differed with age, with 5-year-olds showing greater appraisal accuracy than 4-year-olds. Therefore, the emotional appraisal of these events may also be affected by age and valence when attributing emotions to personal experiences.
Assuntos
Emoções , Memória Episódica , Meio Social , Pré-Escolar , Feminino , Humanos , Masculino , Rememoração MentalRESUMO
The effects of acute sleep deprivation on ß-amyloid (Aß) clearance in the human brain have not been documented. Here we used PET and 18F-florbetaben to measure brain Aß burden (ABB) in 20 healthy controls tested after a night of rested sleep (baseline) and after a night of sleep deprivation. We show that one night of sleep deprivation, relative to baseline, resulted in a significant increase in Aß burden in the right hippocampus and thalamus. These increases were associated with mood worsening following sleep deprivation, but were not related to the genetic risk (APOE genotype) for Alzheimer's disease. Additionally, baseline ABB in a range of subcortical regions and the precuneus was inversely associated with reported night sleep hours. APOE genotyping was also linked to subcortical ABB, suggesting that different Alzheimer's disease risk factors might independently affect ABB in nearby brain regions. In summary, our findings show adverse effects of one-night sleep deprivation on brain ABB and expand on prior findings of higher Aß accumulation with chronic less sleep.
Assuntos
Peptídeos beta-Amiloides/metabolismo , Hipocampo/metabolismo , Privação do Sono/diagnóstico por imagem , Privação do Sono/metabolismo , Tálamo/metabolismo , Adulto , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/genética , Apolipoproteínas E/genética , Feminino , Genótipo , Hipocampo/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Privação do Sono/genética , Tálamo/diagnóstico por imagemRESUMO
A phytoremediation process for lead (Pb) under laboratory conditions on contaminated soil from the Puchuncaví commune, Valparaíso Province, Chile, was carried out. It analyzed the phytoremediation potential of Sarcocornia neei (Lag.) M.A. Alonso and M.B. Crespo. The plants were propagated beforehand and extracted from the El Yali wetland, a RAMSAR 878 site in Valparaíso. Soil fertility and heavy metal concentration analyses of composite samples were conducted, complying with established protocols and standard methodology for chemical and metal analyses. These analyses were conducted in the Soil Analysis Laboratory of the Pontificia Universidad Católica de Valparaíso. The aim was to analyse not only the tissue of plants from both areas but also the soil to identify the changes in different conditions in which the plants live. To determine the type of inferential analysis to be performed, a normality test was applied; however, it was deemed unsuitable, and therefore, the contrasts were developed using nonparametric tests, particularly Wilcoxon. R project software was used in the tests, especially the RCommander package, together with the Jamovi free-license statistical spreadsheet application. The analyses results of the soil samples indicated high concentrations of heavy metals, predominantly Pb at a concentration of 77.97 mg/kg, acidic soil indicated by pH between 5.77 and 6.38, low levels of electrical conductivity, and the presence of organic matter. A phytoremediation efficiency of 99% on soil samples was achieved. Preliminary results were compared against international regulations on the concentration of metals in soil. The histological sections showed that individual plants probably adapted to their environmental conditions.
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Biodegradação Ambiental , Chenopodiaceae/metabolismo , Chumbo/metabolismo , Poluentes do Solo/toxicidade , Chile , Humanos , Chumbo/química , Chumbo/toxicidade , Metais Pesados/química , Metais Pesados/metabolismo , Metais Pesados/toxicidade , Poluentes do Solo/metabolismoRESUMO
Early steps of tissue invasion by Entamoeba histolytica are mediated by adhesion and migration through matrix components such as fibronectin with the participation of the actin cytoskeleton. Striking differences in their produced structures, movement, and migration were found. These observations suggest differential changes in their ability to organize the actin cytoskeleton and, therefore, to modify its morphology after adhesion to fibronectin. To understand these observations, we explore deeper the cytoskeleton pathway of E. histolytica compared to Entamoeba dispar, analyzing the activation and involvement of actin cytoskeleton regulatory proteins such as small GTPases (Rho, Rac1 and Cdc42), myosin IB, paxillin, alpha-actinin, and ARP2/3 during interaction with fibronectin. Results showed a higher activation of Rac1 in E. histolytica compared to E. dispar, while Cdc42 and RhoA were equally activated in both amebae; besides, variations in the amount of myosin IB, paxillin, and ARP2/3 were detected among these species, coinciding and reflected in formation of lamellipodia in E. histolytica and filopodia in E. dispar. These could partially explain the higher invasive capacity of E. histolytica compared to E. dispar, due to its pleomorphic ability, high motility, migration, activation, and abundance of proteins involved in the cytoskeleton arrangement.
Assuntos
Entamoeba/fisiologia , Fibronectinas/farmacologia , GTP Fosfo-Hidrolases/metabolismo , Proteínas dos Microfilamentos/metabolismo , Entamoeba/efeitos dos fármacos , Entamoeba/ultraestrutura , Entamoeba histolytica/ultraestrutura , Regulação da Expressão Gênica/efeitos dos fármacos , Microscopia Confocal , Proteínas de Protozoários/metabolismoRESUMO
Linearolactone (1) and kaempferol (2) have amebicidal activity in in vitro studies. The type of cell death induced by 1 and 2 and their effects on the virulence of E. histolytica were analyzed by transmission and confocal electron microscopy, reactive oxygen species (ROS) production, and apoptosis, detected by flow cytometry with dichlorofluorescein 2',7'-diacetate and annexin-V binding, respectively, and confirmed by TUNEL. The interaction of 1 and 2 with actin was analyzed by docking, and the in vivo amoebicidal activity was established with the Mesocricetus auratus model; amebic liver abscess (ALA) development was evaluated by magnetic resonance (MR) and validated post mortem. In vitro, compounds 1 and 2 caused chromatin condensation, intracellular ROS, and loss of actin structures. Coupling analysis showed that they bind to the allosteric and catalytic sites of actin with binding energies of -11.30 and -8.45 kcal/mol, respectively. Treatments with 1 and 2 induced a decrease in ALA formation without toxic effects on the liver and kidney. Thus, compound 1, but not 2, was able to induce apoptosis-like effects in E. histolytica trophozoites by intracellular production of ROS that affected the actin cytoskeleton structuration. In vivo, compound 1 was more active than compound 2 to reduce the development of ALA.
Assuntos
Citoesqueleto de Actina/efeitos dos fármacos , Diterpenos Clerodânicos/farmacologia , Quempferóis/farmacologia , Abscesso Hepático Amebiano/prevenção & controle , Animais , Cricetinae , Cricetulus , Humanos , Simulação de Acoplamento MolecularRESUMO
Rab proteins constitute the largest group of small GTPases and act as molecular switches in a wide variety of cellular processes, including proliferation, cytoskeleton assembly, and membrane trafficking in all eukaryotic cells. Rab21 has been reported in several eukaryotic cells, and our results suggest that in Entamoeba histolytica, Rab21 is involved in the vesicular traffic associated with the Golgi apparatus, where its function appears to be important to maintain the structure of this organelle. In addition, proteins such as Rab1A and Sec24, identified in this work associated with EhRab21, participate in the traffic of COPII vesicles from the endoplasmic reticulum to the Golgi apparatus and are necessary to maintain the latter's structure in human cells. In addition, EhRab21 probably affects the lysosome biogenesis, as indicated by an increase in the number of lysosomes as a result of the increase in EhRab21 activity. The participation of EhRab21 in the pathogenesis of amebiasis was verified on the amoebic liver abscess formation model using hamsters (Mesocricetus auratus), in which the overexpression of EhRab21Q64L (positive dominant mutant protein) decreased the number of liver abscesses formed.
Assuntos
Vesículas Revestidas pelo Complexo de Proteína do Envoltório/metabolismo , Entamoeba histolytica/metabolismo , Complexo de Golgi/metabolismo , Transporte Proteico/fisiologia , Proteínas rab de Ligação ao GTP/metabolismo , Amebíase/patologia , Animais , Cricetinae , Retículo Endoplasmático/metabolismo , Humanos , Abscesso Hepático Amebiano/patologia , Lisossomos/metabolismo , Proteínas de Transporte Vesicular/metabolismoRESUMO
Epigenetic dysregulation plays a crucial role in cardiovascular diseases. Previously, we reported that acetyltransferase p300 (ATp300) inhibitor L002 prevents hypertension-induced cardiac hypertrophy and fibrosis in a murine model. In this short communication, we show that treatment of hypertensive mice with ATp300-specific small molecule inhibitor L002 or C646 reverses hypertension-induced left ventricular hypertrophy, cardiac fibrosis and diastolic dysfunction, without reducing elevated blood pressures. Biochemically, treatment with L002 and C646 also reverse hypertension-induced histone acetylation and myofibroblast differentiation in murine ventricles. Our results confirm and extend the role of ATp300, a major epigenetic regulator, in the pathobiology of cardiac hypertrophy and fibrosis. Most importantly, we identify the efficacies of ATp300 inhibitors C646 and L002 in reversing hypertension-induced cardiac hypertrophy and fibrosis, and discover new anti-hypertrophic and anti-fibrotic candidates.
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Benzoatos/farmacologia , Cardiomegalia/prevenção & controle , Fibrose/prevenção & controle , Inibidores de Histona Desacetilases/farmacologia , Hipertensão/complicações , Pirazóis/farmacologia , Fatores de Transcrição de p300-CBP/antagonistas & inibidores , Acetilação , Animais , Cardiomegalia/etiologia , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Células Cultivadas , Fibrose/etiologia , Fibrose/metabolismo , Fibrose/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nitrobenzenos , PirazolonasRESUMO
The role of sleep in brain physiology is poorly understood. Recently rodent studies have shown that the glymphatic system clears waste products from brain more efficiently during sleep compared to wakefulness due to the expansion of the interstitial fluid space facilitating entry of cerebrospinal fluid (CSF) into the brain. Here, we studied water diffusivity in the brain during sleep and awake conditions, hypothesizing that an increase in water diffusivity during sleep would occur concomitantly with an expansion of CSF volume - an effect that we predicted based on preclinical findings would be most prominent in cerebellum. We used MRI to measure slow and fast components of the apparent diffusion coefficient (ADC) of water in the brain in 50 healthy participants, in 30 of whom we compared awake versus sleep conditions and in 20 of whom we compared rested-wakefulness versus wakefulness following one night of sleep-deprivation. Sleep compared to wakefulness was associated with increases in slow-ADC in cerebellum and left temporal pole and with decreases in fast-ADC in thalamus, insula, parahippocampus and striatal regions, and the density of sleep arousals was inversely associated with ADC changes. The CSF volume was also increased during sleep and was associated with sleep-induced changes in ADCs in cerebellum. There were no differences in ADCs with wakefulness following sleep deprivation compared to rested-wakefulness. Although we hypothesized increases in ADC with sleep, our findings uncovered both increases in slow ADC (mostly in cerebellum) as well as decreases in fast ADC, which could reflect the distinct biological significance of fast- and slow-ADC values in relation to sleep. While preliminary, our findings suggest a more complex sleep-related glymphatic function in the human brain compared to rodents. On the other hand, our findings of sleep-induced changes in CSF volume provide preliminary evidence that is consistent with a glymphatic transport process in the human brain.
Assuntos
Encéfalo/metabolismo , Líquido Cefalorraquidiano/metabolismo , Sistema Glinfático/fisiologia , Sono/fisiologia , Adulto , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , MasculinoRESUMO
BACKGROUND: Excessive alcohol consumption is associated with reduced cortical thickness (CT) and lower cerebral metabolic rate of glucose (CMRGlu), but the correlation between these 2 measures has not been investigated. METHODS: We tested the association between CT and cerebral CMRGlu in 19 participants with alcohol use disorder (AUD) and 20 healthy controls. Participants underwent 2-Deoxy-2-[18F]fluoroglucose positron emission tomography to map CMRGlu and magnetic resonance imaging to assess CT. RESULTS: Although performance accuracy on a broad range of cognitive domains did not differ significantly between AUD and HC, AUD had widespread decreases in CT and CMRGlu. CMRGlu, normalized to cerebellum (rCMRGlu), showed significant correlation with CT across participants. Although there were large group differences in CMRGlu (>17%) and CT (>6%) in medial orbitofrontal and BA 47, the superior parietal cortex showed large reductions in CMRGlu (~17%) and minimal CT differences (~2.2%). Though total lifetime alcohol (TLA) was associated with CT and rCMRGlu, the causal mediation analysis revealed significant direct effects of TLA on rCMRGlu but not on CT, and there were no significant mediation effects of TLA, CT, and rCMRGlu. CONCLUSIONS: The significant correlation between decrements in CT and CMRGlu across AUD participants is suggestive of alcohol-induced neurotoxicity, whereas the findings that the most metabolically affected regions in AUD had minimal atrophy and vice versa indicates that changes in CT and CMRGlu reflect distinct responses to alcohol across brain regions.
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Alcoolismo/metabolismo , Alcoolismo/patologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Etanol/efeitos adversos , Glucose/metabolismo , Atrofia , Estudos de Casos e Controles , Córtex Cerebral/efeitos dos fármacos , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem , Testes Neuropsicológicos , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Tomografia por Emissão de PósitronsRESUMO
Urinary concentrating ability is central to mammalian water balance and depends on a medullary osmotic gradient generated by a countercurrent multiplication mechanism. Medullary hyperosmolarity is protected from washout by countercurrent exchange and efficient removal of interstitial fluid resorbed from the loop of Henle and collecting ducts. In most tissues, lymphatic vessels drain excess interstitial fluid back to the venous circulation. However, the renal medulla is devoid of classic lymphatics. Studies have suggested that the fenestrated ascending vasa recta (AVRs) drain the interstitial fluid in this location, but this function has not been conclusively shown. We report that late gestational deletion of the angiopoietin receptor endothelial tyrosine kinase 2 (Tie2) or both angiopoietin-1 and angiopoietin-2 prevents AVR formation in mice. The absence of AVR associated with rapid accumulation of fluid and cysts in the medullary interstitium, loss of medullary vascular bundles, and decreased urine concentrating ability. In transgenic reporter mice with normal angiopoietin-Tie2 signaling, medullary AVR exhibited an unusual hybrid endothelial phenotype, expressing lymphatic markers (prospero homeobox protein 1 and vascular endothelial growth factor receptor 3) as well as blood endothelial markers (CD34, endomucin, platelet endothelial cell adhesion molecule 1, and plasmalemmal vesicle-associated protein). Taken together, our data redefine the AVRs as Tie2 signaling-dependent specialized hybrid vessels and provide genetic evidence of the critical role of AVR in the countercurrent exchange mechanism and the structural integrity of the renal medulla.
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Angiopoietina-1/fisiologia , Angiopoietina-2/fisiologia , Líquido Extracelular/metabolismo , Capacidade de Concentração Renal/fisiologia , Medula Renal/irrigação sanguínea , Receptor TIE-2/fisiologia , Angiopoietina-1/deficiência , Angiopoietina-1/genética , Angiopoietina-2/deficiência , Angiopoietina-2/genética , Animais , Padronização Corporal , Linhagem da Célula , Endotélio Vascular , Genes Reporter , Idade Gestacional , Proteínas de Homeodomínio/análise , Doenças Renais Císticas/genética , Medula Renal/embriologia , Medula Renal/fisiologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Miofibroblastos/patologia , Osmose , Receptor TIE-2/deficiência , Receptor TIE-2/genética , Circulação Renal , Transdução de Sinais , Proteínas Supressoras de Tumor/análise , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/análiseRESUMO
Humans can contract anisakiasis by eating fish or squid containing live larvae of the third stage (L3) of the parasitic nematodes of the genus Anisakis, majorly from Anisakis simplex s.s. and Anisakis pegreffii, sibling species of the A. simplex s.l. complex. Most cases diagnosed molecularly are due to A. simplex s.s., although A. pegreffii has also been identified in human cases. Cathepsins are mostly lysosomal multifunctional cysteine proteases and can participate in the pathogenicity of parasites. Cathepsin B and L activities were investigated in the two sibling species of Anisakis mentioned. L3 and L4 of both species were collected during their in vitro development, and cathepsin activity was determined in the range of pH 4.0-8.5, using specific fluorogenic substrates. The activity detected with the substrate Z-FR-AMC (N-α-benzyloxycarbonyl-L-phenylalanyl-L-arginine-7-amido-4-methyl-coumarin) was identified as cathepsin L (optimum pH = 5.0, range 4.0-6.0, p < 0.001). Activity was highest in L3 freshly collected from fish, especially in A. simplex s.s., and decreased during development, which could be related to virulence, invasion of host tissues, and/or intracellular digestion. Cathepsin B-like activity was not identified with either of the substrates used (Z-RR-AMC [N-α-benzyloxycarbonyl-L-arginyl-L-arginine-7-amido-4-methyl-coumarin] and Z-FR-AMC). With Z-RR-AMC, cleaving activity was detected almost exclusively in L4 of A. simplex s.s. (p < 0.05) with optimum pH = 8.0 (range 7.0-8.5). Assays with class-specific protease inhibitors showed that this activity was mainly due to serine proteases [up to 90% inhibition with 4-(2-aminoethyl) benzenesulfonyl fluoride hydrochloride (AEBSF)], although metalloproteases (up to 40-45% inhibition with 1,10 phenanthroline) and slight cysteine protease activity (<15% inhibition with E64 [L-trans-epoxysuccinyl-leucylamido-(4-guanidino)-butane]; putative cathepsin B-like) were also detected. These results show differential serine protease activity between sibling Anisakis species, regulated by larval development, at least in A. simplex s.s. The higher cathepsin L and serine protease activities detected in this species could be related to its greater pathogenicity, reported in experimental animals, compared to that of A. pegreffii.
Assuntos
Anisakis/classificação , Anisakis/enzimologia , Catepsinas/metabolismo , Cisteína Proteases/metabolismo , Serina Proteases/metabolismo , Animais , Anisaquíase/parasitologia , Catepsina L/metabolismo , Decapodiformes/parasitologia , Peixes/parasitologia , Doenças Transmitidas por Alimentos/parasitologia , Humanos , Alimentos Marinhos/parasitologia , Espanha , Especificidade da Espécie , Especificidade por SubstratoRESUMO
Angiotensin-converting enzyme 2 (ACE2) is a carboxypeptidase that potently degrades angiotensin II to angiotensin 1-7. Previous studies showed that injection of the enzymatic ectodomain of recombinant ACE2 (rACE2) markedly increases circulatory levels of ACE2 activity, and effectively lowered blood pressure in angiotensin II-induced hypertension. However, due to the short plasma half-life of rACE2, its therapeutic potential for chronic use is limited. To circumvent this, we generated a chimeric fusion of rACE2 and the immunoglobulin fragment Fc segment to increase its plasma stability. This rACE2-Fc fusion protein retained full peptidase activity and exhibited greatly extended plasma half-life in mice, from less than two hours of the original rACE2, to over a week. A single 2.5 mg/kg injection of rACE2-Fc increased the overall angiotensin II-conversion activities in blood by up to 100-fold and enhanced blood pressure recovery from acute angiotensin II induced hypertension seven days after administration. To assess rACE2-Fc given weekly on cardiac protection, we performed studies in mice continuously infused with angiotensin II for 28 days and in a Renin transgenic mouse model of hypertension. The angiotensin II infused mice achieved sustained blood pressure control and reduced cardiac hypertrophy and fibrosis. In chronic hypertensive transgenic mice, weekly injections of rACE2-Fc effectively lowered plasma angiotensin II and blood pressure. Additionally, rACE2-Fc ameliorated albuminuria, and reduced kidney and cardiac fibrosis. Thus, our chimeric fusion strategy for rACE2-Fc is suitable for future development of new renin angiotensin system-based inhibition therapies.
Assuntos
Hipertensão/tratamento farmacológico , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Peptidil Dipeptidase A/uso terapêutico , Proteínas Recombinantes de Fusão/uso terapêutico , Angiotensina II/administração & dosagem , Angiotensina II/sangue , Enzima de Conversão de Angiotensina 2 , Animais , Linhagem Celular , Modelos Animais de Doenças , Feminino , Meia-Vida , Humanos , Hipertensão/etiologia , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/isolamento & purificação , Fragmentos Fc das Imunoglobulinas/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/isolamento & purificação , Peptidil Dipeptidase A/farmacologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/farmacologia , Renina/genética , Sistema Renina-Angiotensina/efeitos dos fármacos , Resultado do TratamentoRESUMO
Caloric restriction (CR) has anti-epileptic effects in different animal models, at least partially due to inhibition of the mechanistic or mammalian target of rapamycin (mTOR) signaling pathway. Adenosine monophosphate-activated protein kinase (AMPK) inhibits mTOR cascade function if energy levels are low. Since hyper-activation of mTOR participates in epilepsy, its inhibition results in beneficial anti-convulsive effects. A way to attain this is to activate AMPK with metformin. The effects of metformin, alone or combined with CR, on the electrical kindling epilepsy model and the mTOR cascade in the hippocampus and the neocortex were studied. Combined metformin plus CR beneficially affected many kindling aspects, especially those relating to generalized convulsive seizures. Therefore, metformin plus CR could decrease measures of epileptic activity in patients with generalized convulsive seizures. Patients that are obese, overweight or that have metabolic syndrome in addition to having an epileptic disease are an ideal population for clinical trials to test the effectiveness of metformin plus CR.