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1.
Gut Microbes ; 16(1): 2414798, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39468827

RESUMO

Weaning, the transition from a milk-based diet to solid food, coincides with the most significant shift in gut microbiome composition in the lifetime of most mammals. Notably, this period also marks a "window of opportunity" where key components of the immune system develop, and host-microbe interactions shape long-term immune homeostasis thereby influencing the risk of autoimmune and inflammatory diseases. This review provides a comprehensive analysis of the changes in nutrition, microbiota, and host physiology that occur during weaning. We explore how these weaning-associated processes differ across species, lifestyles, and regions of the intestine. Using prinicples of microbial ecology, we propose that the weaning transition is an optimal period for microbiome-targeted therapeutic interventions. Additionally, we suggest that replicating features of the weaning microbiome in adults could promote the successful engraftment of probiotics. Finally, we highlight key research areas that could deepen our understanding of the complex relationships between diet, commensal microbes, and the host, informing the development of more effective microbial therapies.


Assuntos
Microbioma Gastrointestinal , Probióticos , Desmame , Humanos , Animais , Probióticos/administração & dosagem , Interações entre Hospedeiro e Microrganismos , Dieta , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/genética , Bactérias/metabolismo , Intestinos/microbiologia , Intestinos/imunologia
2.
Cell ; 187(19): 5431-5452.e20, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39303691

RESUMO

Breastfeeding and microbial colonization during infancy occur within a critical time window for development, and both are thought to influence the risk of respiratory illness. However, the mechanisms underlying the protective effects of breastfeeding and the regulation of microbial colonization are poorly understood. Here, we profiled the nasal and gut microbiomes, breastfeeding characteristics, and maternal milk composition of 2,227 children from the CHILD Cohort Study. We identified robust colonization patterns that, together with milk components, predict preschool asthma and mediate the protective effects of breastfeeding. We found that early cessation of breastfeeding (before 3 months) leads to the premature acquisition of microbial species and functions, including Ruminococcus gnavus and tryptophan biosynthesis, which were previously linked to immune modulation and asthma. Conversely, longer exclusive breastfeeding supports a paced microbial development, protecting against asthma. These findings underscore the importance of extended breastfeeding for respiratory health and highlight potential microbial targets for intervention.


Assuntos
Aleitamento Materno , Leite Humano , Humanos , Feminino , Leite Humano/microbiologia , Lactente , Pré-Escolar , Asma/microbiologia , Asma/prevenção & controle , Asma/imunologia , Microbiota , Microbioma Gastrointestinal , Masculino , Estudos de Coortes , Recém-Nascido
3.
Gut Microbes ; 16(1): 2387875, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39133869

RESUMO

The intestinal microbiome during infancy and childhood has distinct metabolic functions and microbial composition compared to adults. We recently published a gnotobiotic mouse model of the pre-weaning microbiome (PedsCom), which retains a pre-weaning configuration during the transition from a milk-based diet to solid foods, leads to a stunted immune system, and increases susceptibility to enteric infection. Here, we compared the phylogenetic and metabolic relationships of the PedsCom consortium to two adult-derived gnotobiotic communities, Altered Schaedler Flora and Oligo-Mouse Microbiota 12 (Oligo-MM12). We find that PedsCom contains several unique functions relative to these adult-derived mouse consortia, including differences in carbohydrate and lipid metabolism genes. Notably, amino acid degradation metabolic modules are more prevalent among PedsCom isolates, which is in line with the ready availability of these nutrients in milk. Indeed, metabolomic analysis revealed significantly lower levels of total free amino acids and lower levels of specific amino acids abundant in milk (e.g. glutamine and glutamic acid) in the intestinal contents of adult PedsCom colonized mice compared to Oligo-MM12 controls. Metabolomic analysis of pre-weaning intestinal contents also showed lower levels of amino acids that are replete in milk compared to germ-free controls. Thus, enhanced amino acid metabolism is a prominent feature of the pre-weaning microbiome that may facilitate design of early-life microbiome interventions.


Assuntos
Aminoácidos , Bactérias , Microbioma Gastrointestinal , Vida Livre de Germes , Leite , Desmame , Animais , Aminoácidos/metabolismo , Microbioma Gastrointestinal/fisiologia , Camundongos , Leite/microbiologia , Leite/metabolismo , Bactérias/classificação , Bactérias/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Filogenia , Feminino , Camundongos Endogâmicos C57BL
4.
medRxiv ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38854006

RESUMO

Sepsis is the leading postnatal cause of neonatal mortality worldwide. Globally Klebsiella pneumoniae is the leading cause of sepsis in hospitalized neonates. This study reports development and evaluation of ELISA for anti-Klebsiella IgG using dried blood spot samples and evaluates the association of anti-Klebsiella IgG (anti-Kleb IgG) antibodies in maternal and neonatal samples and the risk of neonatal sepsis. Neonates and their mothers were enrolled at 0-96 hours of life in the neonatal unit of a tertiary referral hospital in Gaborone, Botswana and followed until death or discharge to assess for episodes of blood culture-confirmed neonatal sepsis. Neonates with sepsis had significantly lower levels of Kleb-IgG compared to neonates who did not develop sepsis (Mann-Whitney U, p=0.012). Similarly, samples from mothers of neonates who developed sepsis tended to have less Kleb-IgG compared to mothers of controls (p=0.06). The inverse correlation between Kleb-IgG levels and all-cause bacteremia suggests that maternal Kleb-IgG is broadly protective through cross-reactivity with common bacterial epitopes. These data support the continued use of immunoglobulin assays using DBS samples to explore the role of passive immunity on neonatal sepsis risk and reaffirm the critical need for research supporting the development of maternal vaccines for neonatal sepsis.

5.
Biochem Biophys Res Commun ; 721: 150025, 2024 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-38768546

RESUMO

The causes of Alzheimer's disease (AD) are poorly understood, although many genes are known to be involved in this pathology. To gain insights into the underlying molecular mechanisms, it is essential to identify the relationships between individual AD genes. Previous work has shown that the splice variant E of KLC1 (KLC1_vE) promotes AD, and that the CELF1 gene, which encodes an RNA-binding protein involved in splicing regulation, is at a risk locus for AD. Here, we identified a functional link between CELF1 and KLC1 in AD pathogenesis. Transcriptomic data from human samples from different ethnic groups revealed that CELF1 mRNA levels are low in AD brains, and the splicing pattern of KLC1 is strongly correlated with CELF1 expression levels. Specifically, KLC1_vE is negatively correlated with CELF1. Depletion and overexpression experiments in cultured cells demonstrated that the CELF1 protein down-regulates KLC1_vE. In a cross-linking and immunoprecipitation sequencing (CLIP-seq) database, CELF1 directly binds to KLC1 RNA, following which it likely modulates terminal exon usage, hence KLC1_vE formation. These findings reveal a new pathogenic pathway where a risk allele of CELF1 is associated with reduced CELF1 expression, which up-regulates KLC1_vE to promote AD.


Assuntos
Processamento Alternativo , Doença de Alzheimer , Proteínas CELF1 , Humanos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Proteínas CELF1/metabolismo , Proteínas CELF1/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética
6.
Sci Immunol ; 8(83): eade2335, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37235682

RESUMO

The ability of most patients with selective immunoglobulin A (IgA) deficiency (SIgAD) to remain apparently healthy has been a persistent clinical conundrum. Compensatory mechanisms, including IgM, have been proposed, yet it remains unclear how secretory IgA and IgM work together in the mucosal system and, on a larger scale, whether the systemic and mucosal anti-commensal responses are redundant or have unique features. To address this gap in knowledge, we developed an integrated host-commensal approach combining microbial flow cytometry and metagenomic sequencing (mFLOW-Seq) to comprehensively define which microbes induce mucosal and systemic antibodies. We coupled this approach with high-dimensional immune profiling to study a cohort of pediatric patients with SIgAD and household control siblings. We found that mucosal and systemic antibody networks cooperate to maintain homeostasis by targeting a common subset of commensal microbes. In IgA-deficiency, we find increased translocation of specific bacterial taxa associated with elevated levels of systemic IgG targeting fecal microbiota. Associated features of immune system dysregulation in IgA-deficient mice and humans included elevated levels of inflammatory cytokines, enhanced follicular CD4 T helper cell frequency and activation, and an altered CD8 T cell activation state. Although SIgAD is clinically defined by the absence of serum IgA, the symptomatology and immune dysregulation were concentrated in the SIgAD participants who were also fecal IgA deficient. These findings reveal that mucosal IgA deficiency leads to aberrant systemic exposures and immune responses to commensal microbes, which increase the likelihood of humoral and cellular immune dysregulation and symptomatic disease in patients with IgA deficiency.


Assuntos
Deficiência de IgA , Humanos , Criança , Camundongos , Animais , Imunoglobulina A Secretora , Imunoglobulina M , Homeostase
7.
Cell Host Microbe ; 31(4): 554-570.e7, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-36996818

RESUMO

Disruptions to the intestinal microbiome during weaning lead to negative effects on host immune function. However, the critical host-microbe interactions during weaning that are required for immune system development remain poorly understood. We find that restricting microbiome maturation during weaning stunts immune system development and increases susceptibility to enteric infection. We developed a gnotobiotic mouse model of the early-life microbiome Pediatric Community (PedsCom). These mice develop fewer peripheral regulatory T cells and less IgA, hallmarks of microbiota-driven immune system development. Furthermore, adult PedsCom mice retain high susceptibility to Salmonella infection, which is characteristic of young mice and children. Altogether, our work illustrates how the post-weaning transition in microbiome composition contributes to normal immune maturation and protection from infection. Accurate modeling of the pre-weaning microbiome provides a window into the microbial requirements for healthy development and suggests an opportunity to design microbial interventions at weaning to improve immune development in human infants.


Assuntos
Microbioma Gastrointestinal , Microbiota , Lactente , Adulto , Animais , Humanos , Camundongos , Criança , Vida Livre de Germes , Desmame , Sistema Imunitário
8.
Nature ; 611(7937): 780-786, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36385534

RESUMO

Enteric pathogens are exposed to a dynamic polymicrobial environment in the gastrointestinal tract1. This microbial community has been shown to be important during infection, but there are few examples illustrating how microbial interactions can influence the virulence of invading pathogens2. Here we show that expansion of a group of antibiotic-resistant, opportunistic pathogens in the gut-the enterococci-enhances the fitness and pathogenesis of Clostridioides difficile. Through a parallel process of nutrient restriction and cross-feeding, enterococci shape the metabolic environment in the gut and reprogramme C. difficile metabolism. Enterococci provide fermentable amino acids, including leucine and ornithine, which increase C. difficile fitness in the antibiotic-perturbed gut. Parallel depletion of arginine by enterococci through arginine catabolism provides a metabolic cue for C. difficile that facilitates increased virulence. We find evidence of microbial interaction between these two pathogenic organisms in multiple mouse models of infection and patients infected with C. difficile. These findings provide mechanistic insights into the role of pathogenic microbiota in the susceptibility to and the severity of C. difficile infection.


Assuntos
Clostridioides difficile , Enterococcus , Interações Microbianas , Animais , Humanos , Camundongos , Antibacterianos/farmacologia , Arginina/deficiência , Arginina/metabolismo , Clostridioides difficile/metabolismo , Clostridioides difficile/patogenicidade , Clostridioides difficile/fisiologia , Modelos Animais de Doenças , Farmacorresistência Bacteriana , Enterococcus/efeitos dos fármacos , Enterococcus/metabolismo , Enterococcus/patogenicidade , Enterococcus/fisiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Intestinos/metabolismo , Intestinos/microbiologia , Leucina/metabolismo , Ornitina/metabolismo , Virulência , Suscetibilidade a Doenças
9.
J Pediatric Infect Dis Soc ; 10(Supplement_4): S106-S111, 2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-34951471

RESUMO

Antibody-based assays have been a cornerstone of infectious disease diagnostics for over 100 years [1]. These assays rely on the exquisite sensitivity and specificity of humoral response to almost all infections. While next-generation sequencing (NGS) has tremendous potential to improve diagnostics and uncover host-microbial relationships by directly identifying nucleic acids from infectious microbes, challenges and opportunities for new approaches remain. Here, we review a group of cutting-edge techniques that couple antibody responses with flow cytometry of antibody tagged microbes and NGS. These studies are bringing into focus the dynamic relationship between our immune systems and endogenous microbial communities, which are an important source of pathogens. For simplicity, we use the umbrella term mFLOW-Seq (microbial flow cytometry coupled to NGS) to describe these approaches.


Assuntos
Doenças Transmissíveis , Microbiota , Citometria de Fluxo , Sequenciamento de Nucleotídeos em Larga Escala , Interações entre Hospedeiro e Microrganismos , Humanos
10.
Front Pediatr ; 9: 719679, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34447731

RESUMO

Disseminated toxoplasmosis is an uncommon but highly lethal cause of hyperferritinemic sepsis after hematopoietic cell transplantation (HCT). We report two cases of disseminated toxoplasmosis from two centers in critically ill adolescents after HCT: a 19-year-old who developed fever and altered mental status on day +19 after HCT and a 20-year-old who developed fever and diarrhea on day +52 after HCT. Both patients developed hyperferritinemia with multiple organ dysfunction syndrome and profound immune dysregulation, which progressed to death despite maximal medical therapies. Because disseminated toxoplasmosis is both treatable and challenging to diagnose, it is imperative that intensivists maintain a high index of suspicion for Toxoplasma gondii infection when managing immunocompromised children, particularly in those with known positive T. gondii serologies.

11.
J Alzheimers Dis ; 83(1): 379-394, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34308901

RESUMO

BACKGROUND: Microtubule stabilizing drugs, commonly used as anti-cancer therapeutics, have been proposed for treatment of Alzheimer's disease (AD); however, many do not cross the blood-brain barrier. OBJECTIVE: This research investigated if paclitaxel (PTX) delivered via the intranasal (IN) route could alter the phenotypic progression of AD in 3xTg-AD mice. METHODS: We administered intranasal PTX in 3XTg-AD mice (3xTg-AD n = 15, 10 weeks and n = 10, 44 weeks, PTX: 0.6 mg/kg or 0.9%saline (SAL)) at 2-week intervals. After treatment, 3XTg-AD mice underwent manganese-enhanced magnetic resonance imaging to measure in vivo axonal transport. In a separate 3XTg-AD cohort, PTX-treated mice were tested in a radial water tread maze at 52 weeks of age after four treatments, and at 72 weeks of age, anxiety was assessed by an elevated-plus maze after 14 total treatments. RESULTS: PTX increased axonal transport rates in treated 3XTg-AD compared to controls (p≤0.003). Further investigation using an in vitro neuron model of Aß-induced axonal transport disruption confirmed PTX prevented axonal transport deficits. Confocal microscopy after treatment found fewer phospho-tau containing neurons (5.25±3.8 versus 8.33±2.5, p < 0.04) in the CA1, altered microglia, and reduced reactive astrocytes. PTX improved performance of 3xTg-AD on the water tread maze compared to controls and not significantly different from WT (Day 5, 143.8±43 versus 91.5±77s and Day 12, 138.3±52 versus 107.7±75s for SAL versus PTX). Elevated plus maze revealed that PTX-treated 3xTg-AD mice spent more time exploring open arms (Open arm 129.1±80 versus 20.9±31s for PTX versus SAL, p≤0.05). CONCLUSION: Taken collectively, these findings indicate that intranasal-administered microtubule-stabilizing drugs may offer a potential therapeutic option for treating AD.


Assuntos
Doença de Alzheimer/metabolismo , Antineoplásicos Fitogênicos/uso terapêutico , Barreira Hematoencefálica/metabolismo , Camundongos Transgênicos , Neurônios/metabolismo , Paclitaxel/uso terapêutico , Administração Intranasal , Animais , Transporte Axonal , Encéfalo/metabolismo , Modelos Animais de Doenças , Humanos , Imageamento por Ressonância Magnética , Masculino , Camundongos , Teste do Labirinto Aquático de Morris
12.
Cell Rep ; 31(13): 107825, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32610126

RESUMO

Activated macrophages must carefully calibrate their inflammatory responses to balance efficient pathogen control with inflammation-mediated tissue damage, but the molecular underpinnings of this "balancing act" remain unclear. Using genetically engineered mouse models and primary macrophage cultures, we show that Toll-like receptor (TLR) signaling induces the expression of the transcription factor Spic selectively in patrolling monocytes and tissue macrophages by a nuclear factor κB (NF-κB)-dependent mechanism. Functionally, Spic downregulates pro-inflammatory cytokines and promotes iron efflux by regulating ferroportin expression in activated macrophages. Notably, interferon-gamma blocks Spic expression in a STAT1-dependent manner. High levels of interferon-gamma are indicative of ongoing infection, and in its absence, activated macrophages appear to engage a "default" Spic-dependent anti-inflammatory pathway. We also provide evidence for the engagement of this pathway in sterile inflammation. Taken together, our findings uncover a pathway wherein counter-regulation of Spic by NF-κB and STATs attune inflammatory responses and iron metabolism in macrophages.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Inflamação/metabolismo , Inflamação/patologia , Ferro/metabolismo , Macrófagos/metabolismo , NF-kappa B/metabolismo , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Animais , Transporte Biológico , Regulação para Baixo/genética , Feminino , Heme/metabolismo , Interferon gama/metabolismo , Ligantes , Ativação de Macrófagos , Masculino , Camundongos Endogâmicos C57BL , Monócitos/metabolismo , Receptores Toll-Like/metabolismo
13.
Am J Hosp Palliat Care ; 37(11): 885-889, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32191116

RESUMO

OBJECTIVES: The purpose of this quality improvement (QI) project was to improve the overall process of implementing continuous subcutaneous infusion of opioids (CSCIOs) at the West Palm Beach Veterans Affairs Medical Center and characterize their use in the hospice unit. METHODS: A retrospective chart review from July 2014 to August 2017 was conducted to identify patients who had received CSCIO. Results were analyzed with descriptive statistics.The business philosphy, LEAN methodology "The 5 Whys" was utilized to identify the root causes for delayed infusion timeliness and corrections were implemented by August 2018. Follow-up retrospective time study completed from September 2018 to February 2019. RESULTS: Of the 107 patients identified, 7 were excluded and 100 were reviewed. The mean age was 73 years, 94% male, and 86% Caucasian. A total of 55 veterans received morphine with an average final infusion rate of 2.5 mg/h. A total of 45 Veterans received hydromorphone with a final infusion rate of 1.3 mg/h. The average infusion duration until death was 5 days. Pharmacy verified 94 (94%) orders and nursing verified 55 (55%) orders within 1 hour (gold standard). Sixteen (16%) patients received CSCIO within 1 hour. The 5 Whys identified nursing order verification and pharmacy lack of visual STAT order notification for priority as the potential sources for infusion timeliness improvement. The follow-up time study confirmed improvement in pharmacy delivery time from 29% to 75% on time. CONCLUSION: Pharmacist-led intervention directed to improve CSCIO processes in an inpatient hospice unit utilizing LEAN QI methodology increased timeliness of pharmacy CSCIO delivery.


Assuntos
Hospitais para Doentes Terminais , Farmácia , Idoso , Analgésicos Opioides/uso terapêutico , Feminino , Humanos , Infusões Subcutâneas , Pacientes Internados , Masculino , Dor/tratamento farmacológico , Melhoria de Qualidade , Estudos Retrospectivos
14.
Front Cell Neurosci ; 13: 419, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31616253

RESUMO

Proper intracellular trafficking is essential for neuronal development and function, and when any aspect of this process is dysregulated, the resulting "transportopathy" causes neurological disorders. Hereditary spastic paraplegias (HSPs) are a family of such diseases attributed to over 80 spastic gait genes (SPG), specifically characterized by lower extremity spasticity and weakness. Multiple genes in the trafficking pathway such as those relating to microtubule structure and function and organelle biogenesis are representative disease loci. Microtubule motor proteins, or kinesins, are also causal in HSP, specifically mutations in Kinesin-I/KIF5A (SPG10) and two kinesin-3 family members; KIF1A (SPG30) and KIF1C (SPG58). KIF1A is a motor enriched in neurons, and involved in the anterograde transport of a variety of vesicles that contribute to pre- and post-synaptic assembly, autophagic processes, and neuron survival. KIF1C is ubiquitously expressed and, in addition to anterograde cargo transport, also functions in retrograde transport between the Golgi and the endoplasmic reticulum. Only a handful of KIF1C cargos have been identified; however, many have crucial roles such as neuronal differentiation, outgrowth, plasticity and survival. HSP-related kinesin-3 mutants are characterized mainly as loss-of-function resulting in deficits in motility, regulation, and cargo binding. Gain-of-function mutants are also seen, and are characterized by increased microtubule-on rates and hypermotility. Both sets of mutations ultimately result in misdelivery of critical cargos within the neuron. This likely leads to deleterious cell biological cascades that likely underlie or contribute to HSP clinical pathology and ultimately, symptomology. Due to the paucity of histopathological or cell biological data assessing perturbations in cargo localization, it has been difficult to positively link these mutations to the outcomes seen in HSPs. Ultimately, the goal of this review is to encourage future academic and clinical efforts to focus on "transportopathies" through a cargo-centric lens.

15.
Eur J Immunol ; 49(12): 2252-2254, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31429932

RESUMO

Microbial flow cytometry is a powerful emerging technology with a broad range of applications including the study of complex microbial communities. Immunologists are increasingly using this technology to study antibody responses against pathogenic and commensal microbes. We employed microbial flow cytometry to quantify the proportion of fecal microbes bound by six different Ig isotypes: IgA, IgM, IgG1, IgG2b, IgG2c, and IgG3. In healthy mammals, secretory IgA (sIgA) binds to a subset of commensal microbes in the gut whereas IgG is not typically found in the intestinal tract of healthy mammals. Unexpectedly, fecal microbes isolated from SPF C57BL/6 mice housed in the Hill facility and imported from the vendors The Jackson Laboratory and Taconic Biosciences showed a strong signal in the Brilliant Violet 711 (BV711) channel. Unstained fecal samples from these mice demonstrated that the BV711 signal was due to bacterial autofluorescence. We found that murine diets containing alfalfa induce ex vivo microbial autofluorescence in the far red spectrum, likely due to chlorophyll. Analysis of unstained intestinal microbes is an important step in microbial flow cytometry to identify diet-induced autofluorescence. We recommend fluorophores with emission spectra below 650 nm (e.g. BV421, PE).


Assuntos
Ração Animal , Anticorpos Antibacterianos/imunologia , Fezes/microbiologia , Citometria de Fluxo , Microbioma Gastrointestinal , Imagem Óptica , Animais , Camundongos
16.
Chem Sci ; 10(6): 1634-1643, 2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30842826

RESUMO

Alzheimer's disease (AD) is a multifaceted disease that is characterized by increased oxidative stress, metal-ion dysregulation, and the formation of intracellular neurofibrillary tangles and extracellular amyloid-ß (Aß) aggregates. In this work we report the large affinity binding of the iron(iii) 2,17-bis-sulfonato-5,10,15-tris(pentafluorophenyl)corrole complex FeL1 to the Aß peptide (K d ∼ 10-7) and the ability of the bound FeL1 to act as a catalytic antioxidant in both the presence and absence of Cu(ii) ions. Specific findings are that: (a) an Aß histidine residue binds axially to FeL1; (b) that the resulting adduct is an efficient catalase; (c) this interaction restricts the formation of high molecular weight peptide aggregates. UV-Vis and electron paramagnetic resonance (EPR) studies show that although the binding of FeL1 does not influence the Aß-Cu(ii) interaction (K d ∼ 10-10), bound FeL1 still acts as an antioxidant thereby significantly limiting reactive oxygen species (ROS) generation from Aß-Cu. Overall, FeL1 is shown to bind to the Aß peptide, and modulate peptide aggregation. In addition, FeL1 forms a ternary species with Aß-Cu(ii) and impedes ROS generation, thus showing the promise of discrete metal complexes to limit the toxicity pathways of the Aß peptide.

17.
Acta Neuropathol Commun ; 6(1): 131, 2018 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-30497524

RESUMO

Exposure to the ß-amyloid peptide (Aß) is toxic to neurons and other cell types, but the mechanism(s) involved are still unresolved. Synthetic Aß oligomers can induce ion-permeable pores in synthetic membranes, but whether this ability to damage membranes plays a role in the ability of Aß oligomers to induce tau hyperphosphorylation, or other disease-relevant pathological changes, is unclear. To examine the cellular responses to Aß exposure independent of possible receptor interactions, we have developed an in vivo C. elegans model that allows us to visualize these cellular responses in living animals. We find that feeding C. elegans E. coli expressing human Aß induces a membrane repair response similar to that induced by exposure to the CRY5B, a known pore-forming toxin produced by B. thuringensis. This repair response does not occur when C. elegans is exposed to an Aß Gly37Leu variant, which we have previously shown to be incapable of inducing tau phosphorylation in hippocampal neurons. The repair response is also blocked by loss of calpain function, and is altered by loss-of-function mutations in the C. elegans orthologs of BIN1 and PICALM, well-established risk genes for late onset Alzheimer's disease. To investigate the role of membrane repair on tau phosphorylation directly, we exposed hippocampal neurons to streptolysin O (SLO), a pore-forming toxin that induces a well-characterized membrane repair response. We find that SLO induces tau hyperphosphorylation, which is blocked by calpain inhibition. Finally, we use a novel biarsenical dye-tagging approach to show that the Gly37Leu substitution interferes with Aß multimerization and thus the formation of potentially pore-forming oligomers. We propose that Aß-induced tau hyperphosphorylation may be a downstream consequence of induction of a membrane repair process.


Assuntos
Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/toxicidade , Endossomos/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/toxicidade , Acrilatos/farmacologia , Peptídeos beta-Amiloides/metabolismo , Animais , Animais Geneticamente Modificados , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/toxicidade , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Células Cultivadas , Embrião de Mamíferos , Endossomos/metabolismo , Endotoxinas/toxicidade , Inibidores Enzimáticos/farmacologia , Proteínas Hemolisinas/toxicidade , Hipocampo/citologia , Humanos , Intestinos/citologia , Intestinos/efeitos dos fármacos , Modelos Animais , Morfolinos/farmacologia , Fragmentos de Peptídeos/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Esfingomielina Fosfodiesterase/farmacologia , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo , Cicatrização/efeitos dos fármacos
18.
Consult Pharm ; 33(4): 215-221, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29609700

RESUMO

INTRODUCTION: Topical morphine is a potential treatment option for painful pressure ulcers in hospice and palliative care patients who favor avoidance of systemic opioid therapy. CASE: A 65-year-old male African-American veteran with a painful stage 3 sacral pressure injury was hesitant to take systemic opioids to control his pain, as he wished to stay alert for family and friends. Topical morphine was initiated, and within 24 hours the patient reported a significant reduction in pain on the numeric rating scale. DISCUSSION: Palliative pharmacotherapy is focused on reducing the symptoms of disease while avoiding side effects that impair quality of life. Evidence suggests topical morphine can be an effective treatment option for painful pressure ulcers and can reduce the need for systemic opioids in select patients. CONCLUSION: In the palliative care setting, topical morphine may be considered for compassionate use when treatment with systemic analgesics is undesired, inadequate, or poorly tolerated.


Assuntos
Analgésicos Opioides/administração & dosagem , Morfina/administração & dosagem , Úlcera por Pressão/tratamento farmacológico , Administração Tópica , Idoso , Humanos , Masculino , Dor/tratamento farmacológico , Medição da Dor , Cuidados Paliativos/métodos , Resultado do Tratamento
19.
ACS Chem Neurosci ; 9(6): 1366-1379, 2018 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-29460617

RESUMO

The glycosylation of nucleocytoplasmic proteins with O-linked N-acetylglucosamine residues (O-GlcNAc) is conserved among metazoans and is particularly abundant within brain. O-GlcNAc is involved in diverse cellular processes ranging from the regulation of gene expression to stress response. Moreover, O-GlcNAc is implicated in various diseases including cancers, diabetes, cardiac dysfunction, and neurodegenerative diseases. Pharmacological inhibition of O-GlcNAcase (OGA), the sole enzyme that removes O-GlcNAc, reproducibly slows neurodegeneration in various Alzheimer's disease (AD) mouse models manifesting either tau or amyloid pathology. These data have stimulated interest in the possibility of using OGA-selective inhibitors as pharmaceuticals to alter the progression of AD. The mechanisms mediating the neuroprotective effects of OGA inhibitors, however, remain poorly understood. Here we show, using a range of methods in neuroblastoma N2a cells, in primary rat neurons, and in mouse brain, that selective OGA inhibitors stimulate autophagy through an mTOR-independent pathway without obvious toxicity. Additionally, OGA inhibition significantly decreased the levels of toxic protein species associated with AD pathogenesis in the JNPL3 tauopathy mouse model as well as the 3×Tg-AD mouse model. These results strongly suggest that OGA inhibitors act within brain through a mechanism involving enhancement of autophagy, which aids the brain in combatting the accumulation of toxic protein species. Our study supports OGA inhibition being a feasible therapeutic strategy for hindering the progression of AD and other neurodegenerative diseases. Moreover, these data suggest more targeted strategies to stimulate autophagy in an mTOR-independent manner may be found within the O-GlcNAc pathway. These findings should aid the advancement of OGA inhibitors within the clinic.


Assuntos
Autofagia/efeitos dos fármacos , Serina-Treonina Quinases TOR/farmacologia , Doença de Alzheimer/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Modelos Animais de Doenças , Humanos , Neurônios/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Tauopatias/tratamento farmacológico , Tauopatias/metabolismo , Proteínas tau/efeitos dos fármacos , Proteínas tau/metabolismo
20.
J Pain Palliat Care Pharmacother ; 32(4): 240-247, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31290723

RESUMO

Clinical pharmacy interventions have been shown to improve medication therapy, prevent undesirable side effects, and improve patients' clinical outcomes in a number of settings; however, limited data exist to characterize clinical pharmacy specialist (CPS) providers' interventions in an inpatient hospice Veteran Affairs (VA) setting. The primary objective of this quality improvement (QI) project was to quantify the number and types of pharmacy interventions implemented from the Pharmacists Achieve Results with Medications Documentation (PhARMD) tool for inpatient hospice patient encounters in a VA medical center. A total of 453 interventions during 185 patient care encounters were documented by CPS providers between September 1, 2016, and December 31, 2016. These interventions were documented across 32 unique patients, with an average of 14.2 interventions made per patient during this period. CPS providers frequently intervened to optimize pharmacotherapy for the treatment of pain (42.38%), terminal agitation (5.08%), and nausea (3.97%). Additionally, CPS providers played a significant role in the deprescribing of medication by discontinuing drugs no longer indicated (18.3%). These results substantiate the valuable contribution to patient care that the CPS providers make in optimizing symptom management and deprescribing at end-of-life. Future studies are needed to characterize the potential cost savings of CPS provider services in the inpatient hospice setting.


Assuntos
Hospitais para Doentes Terminais/estatística & dados numéricos , Hospitais de Veteranos/estatística & dados numéricos , Erros de Medicação/prevenção & controle , Farmacêuticos/estatística & dados numéricos , Serviço de Farmácia Hospitalar/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos , Melhoria de Qualidade , Estados Unidos , United States Department of Veterans Affairs , United States Government Agencies , Veteranos
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