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1.
Blood ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38848513

RESUMO

Comparison of the 2007 EORTC/ISCL and the 2022 EORTC/ISCL/USCLC blood staging guidelines for cutaneous T-cell lymphoma at a single institution reveals the newer guidelines fail to detect a subset of Sézary syndrome patients with low blood burden.

2.
PLoS Biol ; 21(4): e3002066, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37053271

RESUMO

With emerging resistance to frontline treatments, it is vital that new antimalarial drugs are identified to target Plasmodium falciparum. We have recently described a compound, MMV020291, as a specific inhibitor of red blood cell (RBC) invasion, and have generated analogues with improved potency. Here, we generated resistance to MMV020291 and performed whole genome sequencing of 3 MMV020291-resistant populations. This revealed 3 nonsynonymous single nucleotide polymorphisms in 2 genes; 2 in profilin (N154Y, K124N) and a third one in actin-1 (M356L). Using CRISPR-Cas9, we engineered these mutations into wild-type parasites, which rendered them resistant to MMV020291. We demonstrate that MMV020291 reduces actin polymerisation that is required by the merozoite stage parasites to invade RBCs. Additionally, the series inhibits the actin-1-dependent process of apicoplast segregation, leading to a delayed death phenotype. In vitro cosedimentation experiments using recombinant P. falciparum proteins indicate that potent MMV020291 analogues disrupt the formation of filamentous actin in the presence of profilin. Altogether, this study identifies the first compound series interfering with the actin-1/profilin interaction in P. falciparum and paves the way for future antimalarial development against the highly dynamic process of actin polymerisation.


Assuntos
Antimaláricos , Malária Falciparum , Humanos , Plasmodium falciparum/metabolismo , Actinas/genética , Actinas/metabolismo , Profilinas/genética , Profilinas/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Malária Falciparum/tratamento farmacológico , Malária Falciparum/prevenção & controle , Malária Falciparum/genética , Eritrócitos/parasitologia , Antimaláricos/farmacologia
3.
Med Res Rev ; 43(6): 2303-2351, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37232495

RESUMO

Humans have lived in tenuous battle with malaria over millennia. Today, while much of the world is free of the disease, areas of South America, Asia, and Africa still wage this war with substantial impacts on their social and economic development. The threat of widespread resistance to all currently available antimalarial therapies continues to raise concern. Therefore, it is imperative that novel antimalarial chemotypes be developed to populate the pipeline going forward. Phenotypic screening has been responsible for the majority of the new chemotypes emerging in the past few decades. However, this can result in limited information on the molecular target of these compounds which may serve as an unknown variable complicating their progression into clinical development. Target identification and validation is a process that incorporates techniques from a range of different disciplines. Chemical biology and more specifically chemo-proteomics have been heavily utilized for this purpose. This review provides an in-depth summary of the application of chemo-proteomics in antimalarial development. Here we focus particularly on the methodology, practicalities, merits, and limitations of designing these experiments. Together this provides learnings on the future use of chemo-proteomics in antimalarial development.


Assuntos
Antimaláricos , Antagonistas do Ácido Fólico , Malária , Humanos , Antimaláricos/química , Proteômica , Malária/tratamento farmacológico , Malária/prevenção & controle , Resistência a Medicamentos
4.
J Drugs Dermatol ; 22(4): 393-397, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37026883

RESUMO

BACKGROUND: Chronic spontaneous urticaria (CSU) is a debilitating disease for which many patients are inadequately treated. However, recent advancements in our understanding of the disease pathophysiology allow us to develop therapies that are more effective for CSU. It may be possible in the future to select personalized treatments based on a patient’s autoimmune endotype. This paper reviews current knowledge on CSU pathogenesis and treatment. It also reviews data for drugs being developed for the treatment of CSU, as listed on ClinicalTrials.gov. J Drugs Dermatol. 2023;22(4): doi:10.36849/JDD.7113 Citation: Nguyen W, Liu W, Paul S. Yamauchi PS. Drugs in development for chronic spontaneous urticaria. J Drugs Dermatol. 2023;22(4):393-397. doi:10.36849/JDD.7113.


Assuntos
Urticária Crônica , Urticária , Humanos , Urticária/diagnóstico , Urticária/tratamento farmacológico , Doença Crônica , Urticária Crônica/diagnóstico , Urticária Crônica/tratamento farmacológico
5.
BMC Med Educ ; 22(1): 838, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36471288

RESUMO

BACKGROUND: Mental Health First Aid (MHFA) training teaches participants how to respond to mental health crises, including suicide. Little is known about the impact of training on participants' observed MHFA behaviours. This exploratory study aimed to compare MHFA-trained Australian and US student pharmacists' performance and suicide assessment language during simulated patient role-play (SPRP) assessments. METHODS: Student pharmacists (n = 265) completed MHFA training and participated (n = 81) in SPRPs with simulated patients (SP) who were people with lived experience of mental illness. Each SPRP was marked by three raters (student, tutor and SP). One-way ANOVA, chi-squared tests and independent samples t-tests were used to compare scores and pass/fail rates, where appropriate. Transcribed audio-recordings of suicide assessments underwent discourse analysis. A chi-squared test was conducted to investigate the differences in how suicide assessment language was coded across six discursive frames ('confident'/'timid', 'empathetic'/'apathetic', and 'direct'/'indirect'). RESULTS: Three raters assessed 81 SPRPs, resulting in quantitative analysis of 243 rubrics. There were no significant differences between student pharmacists' mean scores and pass/fail rates across countries. Overall, both cohorts across Australia and the US performed better during the mania scenario, with a low failure rate of 13.9 and 19.0%, respectively. Most students in both countries passed their SPRP assessment; however, 27.8% did not assess for suicide or used indirect language during suicide assessment, despite completing MHFA training. Australian student pharmacists demonstrated, more direct language (76.9% versus 67.9%) and empathy (42.3% versus 32.1%) but less confidence (57.7% versus 60.7%) compared to US student pharmacists, during their suicide assessment; however, these differences were not statistically significant. CONCLUSIONS: Findings indicate most MHFA-trained student pharmacists from Australia and the US can provide MHFA during SPRPs, as well as assess for suicide directly, empathetically and confidently. This exploratory study demonstrates the importance of practicing skills post-training and the need for further research exploring participants' hesitance to assess for suicide, despite training completion.


Assuntos
Saúde Mental , Suicídio , Humanos , Estados Unidos , Primeiros Socorros , Idioma , Austrália
6.
PLoS Biol ; 16(6): e2004663, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29889904

RESUMO

Nuclear factor κB (NF-κB) is a transcription factor important for regulating innate and adaptive immunity, cellular proliferation, apoptosis, and senescence. Dysregulation of NF-κB and its upstream regulator IκB kinase (IKK) contributes to the pathogenesis of multiple inflammatory and degenerative diseases as well as cancer. An 11-amino acid peptide containing the NF-κB essential modulator (NEMO)-binding domain (NBD) derived from the C-terminus of ß subunit of IKK, functions as a highly selective inhibitor of the IKK complex by disrupting the association of IKKß and the IKKγ subunit NEMO. A structure-based pharmacophore model was developed to identify NBD mimetics by in silico screening. Two optimized lead NBD mimetics, SR12343 and SR12460, inhibited tumor necrosis factor α (TNF-α)- and lipopolysaccharide (LPS)-induced NF-κB activation by blocking the interaction between IKKß and NEMO and suppressed LPS-induced acute pulmonary inflammation in mice. Chronic treatment of a mouse model of Duchenne muscular dystrophy (DMD) with SR12343 and SR12460 attenuated inflammatory infiltration, necrosis and muscle degeneration, demonstrating that these small-molecule NBD mimetics are potential therapeutics for inflammatory and degenerative diseases.


Assuntos
Materiais Biomiméticos/farmacologia , Quinase I-kappa B/antagonistas & inibidores , Distrofia Muscular de Duchenne/tratamento farmacológico , Pneumonia/tratamento farmacológico , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Materiais Biomiméticos/química , Linhagem Celular , Feminino , Células HEK293 , Humanos , Quinase I-kappa B/química , Quinase I-kappa B/metabolismo , Inflamação/tratamento farmacológico , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos C57BL , Necrose/tratamento farmacológico , Domínios Proteicos , Células RAW 264.7
7.
Bioorg Chem ; 115: 105244, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34452759

RESUMO

Malaria is a devastating parasitic disease caused by parasites from the genus Plasmodium. Therapeutic resistance has been reported against all clinically available antimalarials, threatening our ability to control the disease and therefore there is an ongoing need for the development of novel antimalarials. Towards this goal, we identified the 2-(N-phenyl carboxamide) triazolopyrimidine class from a high throughput screen of the Janssen Jumpstarter library against the asexual stages of the P. falciparum parasite. Here we describe the structure activity relationship of the identified class and the optimisation of asexual stage activity while maintaining selectivity against the human HepG2 cell line. The most potent analogues from this study were shown to exhibit equipotent activity against P. falciparum multidrug resistant strains and P. knowlesi asexual parasites. Asexual stage phenotyping studies determined the triazolopyrimidine class arrests parasites at the trophozoite stage, but it is likely these parasites are still metabolically active until the second asexual cycle, and thus have a moderate to slow onset of action. Non-NADPH dependent degradation of the central carboxamide and low aqueous solubility was observed in in vitro ADME profiling. A significant challenge remains to correct these liabilities for further advancement of the 2-(N-phenyl carboxamide) triazolopyrimidine scaffold as a potential moderate to slow acting partner in a curative or prophylactic antimalarial treatment.


Assuntos
Antimaláricos/farmacologia , Eritrócitos/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Plasmodium knowlesi/efeitos dos fármacos , Purinas/farmacologia , Antimaláricos/síntese química , Antimaláricos/química , Relação Dose-Resposta a Droga , Eritrócitos/parasitologia , Humanos , Estrutura Molecular , Testes de Sensibilidade Parasitária , Purinas/síntese química , Purinas/química , Relação Estrutura-Atividade
8.
BMC Public Health ; 21(1): 822, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33926403

RESUMO

BACKGROUND: Biannual distribution of azithromycin to children 1-59 months old reduced mortality by 14% in a cluster-randomized trial. The World Health Organization has proposed targeting this intervention to the subgroup of children 1-11 months old to reduce selection for antimicrobial resistance. Here, we describe a trial designed to determine the impact of age-based targeting of biannual azithromycin on mortality and antimicrobial resistance. METHODS: AVENIR is a cluster-randomized, placebo-controlled, double-masked, response-adaptive large simple trial in Niger. During the 2.5-year study period, 3350 communities are targeted for enrollment. In the first year, communities in the Dosso region will be randomized 1:1:1 to 1) azithromycin 1-11: biannual azithromycin to children 1-11 months old with placebo to children 12-59 months old, 2) azithromycin 1-59: biannual azithromycin to children 1-59 months old, or 3) placebo: biannual placebo to children 1-59 months old. Regions enrolled after the first year will be randomized with an updated allocation based on the probability of mortality in children 1-59 months in each arm during the preceding study period. A biannual door-to-door census will be conducted to enumerate the population, distribute azithromycin and placebo, and monitor vital status. Primary mortality outcomes are defined as all-cause mortality rate (deaths per 1000 person-years) after 2.5 years from the first enrollment in 1) children 1-59 months old comparing the azithromycin 1-59 and placebo arms, 2) children 1-11 months old comparing the azithromycin 1-11 and placebo arm, and 3) children 12-59 months in the azithromycin 1-11 and azithromycin 1-59 arms. In the Dosso region, 50 communities from each arm will be followed to monitor antimicrobial resistance. Primary resistance outcomes will be assessed after 2 years of distributions and include 1) prevalence of genetic determinants of macrolide resistance in nasopharyngeal samples from children 1-59 months old, and 2) load of genetic determinants of macrolide resistance in rectal samples from children 1-59 months old. DISCUSSION: As high-mortality settings consider this intervention, the results of this trial will provide evidence to support programmatic and policy decision-making on age-based strategies for azithromycin distribution to promote child survival. TRIAL REGISTRATION: This trial was registered on January 13, 2020 (clinicaltrials.gov: NCT04224987 ).


Assuntos
Antibacterianos , Azitromicina , Antibacterianos/uso terapêutico , Azitromicina/uso terapêutico , Criança , Pré-Escolar , Farmacorresistência Bacteriana , Humanos , Lactente , Macrolídeos , Administração Massiva de Medicamentos , Níger/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
J Am Pharm Assoc (2003) ; 61(6): 678-693.e3, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34483057

RESUMO

BACKGROUND: Patients may contribute to various aspects of student pharmacists' education within clinical, experiential and educational settings. There is an emerging body of literature describing and evaluating the contribution of patients to health care education; however, little is known about patients' contribution to pharmacy education specifically within educational settings. OBJECTIVE: To explore the evidence relating to the involvement of patients in the education of student pharmacists, in terms of the nature, extent, and outcomes of their contribution. METHODS: A systematic literature search was undertaken within Embase, MEDLINE, Education Resources Information Center, International Pharmaceutical Abstracts, PubMed, PsycINFO, CINAHL, and Scopus databases from inception to April 10, 2020. Inclusion criteria included primary research studies reporting on the active involvement of patients in pharmacy education, within an educational setting. Quality assessment appraisal for the included studies was conducted using the Mixed Methods Appraisal Tool. RESULTS: Twelve studies were eligible for inclusion in this systematic review. Nine studies explored the use of patients as educators providing valuable insight about their lived experience. Six studies involved patients in question-and-answer sessions, providing students with opportunities to inquire about their lived experience in relation to medicines, health care, and medical conditions. Studies that reported on students' learning outcomes demonstrated improvements in communication skills, deeper understanding of patients' lived experience particularly relating to mental illness, and increased confidence in providing care for patients. Among patients, participation in the educational process led to greater satisfaction, empowerment, and knowledge from sharing personal experiences. There were no clinical outcomes measured among patients participating in the included studies. The 5 nonrandomized quantitative studies ranged from low to moderate levels of quality, the 4 mixed-methods studies were of low quality, and the 3 qualitative studies were of high quality. CONCLUSION: The involvement of patients in the education of student pharmacists was found to benefit both patients and students. Student-specific outcomes included development of communication skills and new insights about patients' lived experience. Further research is needed to better understand the long-term impact of patient involvement in pharmacy education, in terms of students' learning outcomes and clinical outcomes among patients.


Assuntos
Farmacêuticos , Estudantes , Humanos , Participação do Paciente , Pesquisa Qualitativa
10.
Proc Natl Acad Sci U S A ; 114(36): 9731-9736, 2017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28827363

RESUMO

When food resources are scarce, endothermic animals can lower core body temperature (Tb). This phenomenon is believed to be part of an adaptive mechanism that may have evolved to conserve energy until more food becomes available. Here, we found in the mouse that the insulin-like growth factor 1 receptor (IGF-1R) controls this response in the central nervous system. Pharmacological or genetic inhibition of IGF-1R enhanced the reduction of temperature and of energy expenditure during calorie restriction. Full blockade of IGF-1R affected female and male mice similarly. In contrast, genetic IGF-1R dosage was effective only in females, where it also induced transient and estrus-specific hypothermia in animals fed ad libitum. These effects were regulated in the brain, as only central, not peripheral, pharmacological activation of IGF-1R prevented hypothermia during calorie restriction. Targeted IGF-1R knockout selectively in forebrain neurons revealed that IGF signaling also modulates calorie restriction-dependent Tb regulation in regions rostral of the canonical hypothalamic nuclei involved in controlling body temperature. In aggregate, these data identify central IGF-1R as a mediator of the integration of nutrient and temperature homeostasis. They also show that calorie restriction, IGF-1R signaling, and body temperature, three of the main regulators of metabolism, aging, and longevity, are components of the same pathway.


Assuntos
Restrição Calórica/efeitos adversos , Hipotermia/fisiopatologia , Receptor IGF Tipo 1/fisiologia , Envelhecimento/fisiologia , Animais , Metabolismo Energético/fisiologia , Feminino , Dosagem de Genes , Homeostase/fisiologia , Hipotermia/etiologia , Hipotermia/prevenção & controle , Longevidade/fisiologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Podofilotoxina/análogos & derivados , Podofilotoxina/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/genética , Caracteres Sexuais , Transdução de Sinais/fisiologia
11.
Appl Geochem ; 119: 1-104632, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33746355

RESUMO

Urbanization contributes to the formation of novel elemental combinations and signatures in terrestrial and aquatic watersheds, also known as 'chemical cocktails.' The composition of chemical cocktails evolves across space and time due to: (1) elevated concentrations from anthropogenic sources, (2) accelerated weathering and corrosion of the built environment, (3) increased drainage density and intensification of urban water conveyance systems, and (4) enhanced rates of geochemical transformations due to changes in temperature, ionic strength, pH, and redox potentials. Characterizing chemical cocktails and underlying geochemical processes is necessary for: (1) tracking pollution sources using complex chemical mixtures instead of individual elements or compounds; (2) developing new strategies for co-managing groups of contaminants; (3) identifying proxies for predicting transport of chemical mixtures using continuous sensor data; and (4) determining whether interactive effects of chemical cocktails produce ecosystem-scale impacts greater than the sum of individual chemical stressors. First, we discuss some unique urban geochemical processes which form chemical cocktails, such as urban soil formation, human-accelerated weathering, urban acidification-alkalinization, and freshwater salinization syndrome. Second, we review and synthesize global patterns in concentrations of major ions, carbon and nutrients, and trace elements in urban streams across different world regions and make comparisons with reference conditions. In addition to our global analysis, we highlight examples from some watersheds in the Baltimore-Washington DC region, which show increased transport of major ions, trace metals, and nutrients across streams draining a well-defined land-use gradient. Urbanization increased the concentrations of multiple major and trace elements in streams draining human-dominated watersheds compared to reference conditions. Chemical cocktails of major and trace elements were formed over diurnal cycles coinciding with changes in streamflow, dissolved oxygen, pH, and other variables measured by high-frequency sensors. Some chemical cocktails of major and trace elements were also significantly related to specific conductance (p<0.05), which can be measured by sensors. Concentrations of major and trace elements increased, peaked, or decreased longitudinally along streams as watershed urbanization increased, which is consistent with distinct shifts in chemical mixtures upstream and downstream of other major cities in the world. Our global analysis of urban streams shows that concentrations of multiple elements along the Periodic Table significantly increase when compared with reference conditions. Furthermore, similar biogeochemical patterns and processes can be grouped among distinct mixtures of elements of major ions, dissolved organic matter, nutrients, and trace elements as chemical cocktails. Chemical cocktails form in urban waters over diurnal cycles, decades, and throughout drainage basins. We conclude our global review and synthesis by proposing strategies for monitoring and managing chemical cocktails using source control, ecosystem restoration, and green infrastructure. We discuss future research directions applying the watershed chemical cocktail approach to diagnose and manage environmental problems. Ultimately, a chemical cocktail approach targeting sources, transport, and transformations of different and distinct elemental combinations is necessary to more holistically monitor and manage the emerging impacts of chemical mixtures in the world's fresh waters.

12.
Artigo em Inglês | MEDLINE | ID: mdl-30559138

RESUMO

A series of 4-amino 2-anilinoquinazolines optimized for activity against the most lethal malaria parasite of humans, Plasmodium falciparum, was evaluated for activity against other human Plasmodium parasites and related apicomplexans that infect humans and animals. Four of the most promising compounds from the 4-amino 2-anilinoquinazoline series were equally as effective against the asexual blood stages of the zoonotic P. knowlesi, suggesting that they could also be effective against the closely related P. vivax, another important human pathogen. The 2-anilinoquinazoline compounds were also potent against an array of P. falciparum parasites resistant to clinically available antimalarial compounds, although slightly less so than against the drug-sensitive 3D7 parasite line. The apicomplexan parasites Toxoplasma gondii, Babesia bovis, and Cryptosporidium parvum were less sensitive to the 2-anilinoquinazoline series with a 50% effective concentration generally in the low micromolar range, suggesting that the yet to be discovered target of these compounds is absent or highly divergent in non-Plasmodium parasites. The 2-anilinoquinazoline compounds act as rapidly as chloroquine in vitro and when tested in rodents displayed a half-life that contributed to the compound's capacity to clear P. falciparum blood stages in a humanized mouse model. At a dose of 50 mg/kg of body weight, adverse effects to the humanized mice were noted, and evaluation against a panel of experimental high-risk off targets indicated some potential off-target activity. Further optimization of the 2-anilinoquinazoline antimalarial class will concentrate on improving in vivo efficacy and addressing adverse risk.


Assuntos
Compostos de Anilina/farmacologia , Antiparasitários/farmacologia , Babesia bovis/efeitos dos fármacos , Cryptosporidium parvum/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Quinazolinas/farmacologia , Toxoplasma/efeitos dos fármacos , Animais , Antimaláricos/farmacologia , Linhagem Celular , Cloroquina/farmacologia , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Testes de Sensibilidade Parasitária , Ratos , Ratos Sprague-Dawley
13.
Alcohol Clin Exp Res ; 43(12): 2547-2558, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31589333

RESUMO

BACKGROUND: Adolescence is a critical period for neural development, and alcohol exposure during adolescence can lead to an elevated risk for health consequences as well as alcohol use disorders. Clinical and experimental data suggest that chronic alcohol exposure may produce immunomodulatory effects that can lead to the activation of pro-inflammatory cytokine pathways as well as microglial markers. The present study evaluated, in brain and blood, the effects of adolescent alcohol exposure and withdrawal on microglia and on the most representative pro- and anti-inflammatory cytokines and major chemokines that can contribute to the establishing of a neuroinflammatory environment. METHODS: Wistar rats (males, n = 96) were exposed to ethanol (EtOH) vapors, or air control, for 5 weeks over adolescence (PD22-PD58). Brains and blood samples were collected at 3 time points: (i) after 35 days of vapor/air exposure (PD58); (ii) after 1 day of withdrawal (PD59), and (iii) 28 days after withdrawal (PD86). The ionized calcium-binding adapter molecule 1 (Iba-1) was used to index microglial activation, and cytokine/chemokine responses were analyzed using magnetic bead panels. RESULTS: After 35 days of adolescent vapor exposure, a significant increase in Iba-1 immunoreactivity was seen in amygdala, frontal cortex, hippocampus, and substantia nigra. However, Iba-1 density returned to control levels at both 1 day and 28 days of withdrawal except in the hippocampus where Iba-1 density was significantly lower than controls. In serum, adolescent EtOH exposure induced a reduction in IL-13 and an increase in fractalkine at day 35. After 1 day of withdrawal, IL-18 was reduced, and IP-10 was elevated, whereas both IP-10 and IL-10 were elevated at 28 days following withdrawal. In the frontal cortex, adolescent EtOH exposure induced an increase in IL-1ß at day 35, and 28 days of withdrawal, and IL-10 was increased after 28 days of withdrawal. CONCLUSION: These data demonstrate that EtOH exposure during adolescence produces significant microglial activation; however, inflammatory markers seen in the blood appear to differ from those observed in the brain.


Assuntos
Encéfalo/metabolismo , Citocinas/metabolismo , Etanol/efeitos adversos , Síndrome de Abstinência a Substâncias/metabolismo , Fatores Etários , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Citocinas/sangue , Masculino , Proteínas dos Microfilamentos/metabolismo , Microglia/metabolismo , Ratos , Síndrome de Abstinência a Substâncias/sangue , Fatores de Tempo
14.
Proc Natl Acad Sci U S A ; 113(1): 26-33, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26668358

RESUMO

Diacylglycerol lipases (DAGLα and DAGLß) convert diacylglycerol to the endocannabinoid 2-arachidonoylglycerol. Our understanding of DAGL function has been hindered by a lack of chemical probes that can perturb these enzymes in vivo. Here, we report a set of centrally active DAGL inhibitors and a structurally related control probe and their use, in combination with chemical proteomics and lipidomics, to determine the impact of acute DAGL blockade on brain lipid networks in mice. Within 2 h, DAGL inhibition produced a striking reorganization of bioactive lipids, including elevations in DAGs and reductions in endocannabinoids and eicosanoids. We also found that DAGLα is a short half-life protein, and the inactivation of DAGLs disrupts cannabinoid receptor-dependent synaptic plasticity and impairs neuroinflammatory responses, including lipopolysaccharide-induced anapyrexia. These findings illuminate the highly interconnected and dynamic nature of lipid signaling pathways in the brain and the central role that DAGL enzymes play in regulating this network.


Assuntos
Ácidos Araquidônicos/metabolismo , Encéfalo/efeitos dos fármacos , Diglicerídeos/metabolismo , Endocanabinoides/metabolismo , Inibidores Enzimáticos/farmacologia , Glicerídeos/metabolismo , Lipase Lipoproteica/antagonistas & inibidores , Plasticidade Neuronal/efeitos dos fármacos , Animais , Encéfalo/enzimologia , Encéfalo/metabolismo , Inibidores Enzimáticos/química , Lipase Lipoproteica/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Canabinoides/metabolismo , Transdução de Sinais/efeitos dos fármacos
15.
J Neurosci ; 36(18): 5170-80, 2016 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-27147667

RESUMO

UNLABELLED: The proinflammatory cytokine IL-18 has central anorexigenic effects and was proposed to contribute to loss of appetite observed during sickness. Here we tested in the mouse the hypothesis that IL-18 can decrease food intake by acting on neurons of the bed nucleus of the stria terminalis (BST), a component of extended amygdala recently shown to influence feeding via its projections to the lateral hypothalamus (LH). We found that both subunits of the heterodimeric IL-18 receptor are highly expressed in the BST and that local injection of recombinant IL-18 (50 ng/ml) significantly reduced c-fos activation and food intake for at least 6 h. Electrophysiological experiments performed in BST brain slices demonstrated that IL-18 strongly reduces the excitatory input on BST neurons through a presynaptic mechanism. The effects of IL-18 are cell-specific and were observed in Type III but not in Type I/II neurons. Interestingly, IL-18-sensitve Type III neurons were recorded in the juxtacapsular BST, a region that contains BST-LH projecting neurons. Reducing the excitatory input on Type III GABAergic neurons, IL-18 can increase the firing of glutamatergic LH neurons through a disinhibitory mechanism. Imbalance between excitatory and inhibitory activity in the LH can induce changes in food intake. Effects of IL-18 were mediated by the IL-18R because they were absent in neurons from animals null for IL-18Rα (Il18ra(-/-)), which lack functional IL-18 receptors. In conclusion, our data show that IL-18 may inhibit feeding by inhibiting the activity of BST Type III GABAergic neurons. SIGNIFICANCE STATEMENT: Loss of appetite during sickness is a common and often debilitating phenomenon. Although proinflammatory cytokines are recognized as mediators of these anorexigenic effects, their mechanism and sites of action remain poorly understood. Here we show that interleukin 18, an anorexigenic cytokine, can act on neurons of the bed nucleus of the stria terminalis to reduce food intake via the IL-18 receptor. The findings identify a site and a mode of action that indicate targets for the treatment of cachexia or other eating disorders.


Assuntos
Comportamento Alimentar/fisiologia , Interleucina-18/fisiologia , Núcleos Septais/fisiologia , Animais , Fenômenos Eletrofisiológicos/fisiologia , Região Hipotalâmica Lateral/fisiologia , Interleucina-18/biossíntese , Interleucina-18/genética , Subunidade alfa de Receptor de Interleucina-18/genética , Subunidade alfa de Receptor de Interleucina-18/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/fisiologia , Proteínas Recombinantes/farmacologia , Sinapses/efeitos dos fármacos , Ácido gama-Aminobutírico/fisiologia
16.
J Neuroinflammation ; 14(1): 88, 2017 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-28427412

RESUMO

BACKGROUND: The majority of Parkinson's disease (PD) cases are sporadic and idiopathic suggesting that this neurodegenerative disorder is the result of both environmental and genetic factors. Stress and neuroinflammation are among the factors being investigated for their possible contributions to PD. Experiments in rodents showed that severe chronic stress can reduce the number of dopaminergic neurons in the substantia nigra pars compacta (SNc); the same cells that are lost in PD. These actions are at least in part mediated by increased oxidative stress. Here, we tested the hypothesis that the interleukin-13 receptor alpha 1 (IL-13Rα1), a cytokine receptor whose activation increases the vulnerability of dopaminergic neurons to oxidative damage, participates in the stress-dependent damage of these neurons. METHODS: Mice were subject to daily sessions of 8 h (acute) stress for 16 weeks (5 days a week), a procedure previously showed to induce loss of dopaminergic neurons in the SNc. The source and the kinetics of interleukin-13 (IL-13), the endogenous ligand of IL-13Rα1, were evaluated 0, 1, 3, 6, and 8 h and at 16 weeks of stress. Identification of IL-13 producing cell-type was performed by immunofluorescent and by in situ hybridization experiments. Markers of oxidative stress, microglia activation, and the number of dopaminergic neurons in IL-13Rα1 knock-out animals (Il13ra1 Y/ - ) and their wild-type littermates (Il13ra1 Y/+ ) were evaluated at 16 weeks of stress and at 20 weeks, following a 4 week non-stressed period and compared to non-stressed mice. RESULTS: IL-13 was expressed in microglial cells within the SN and in a fraction of the tyrosine hydroxylase-positive neurons in the SNc. IL-13 levels were elevated during daily stress and peaked at 6 h. 16 weeks of chronic restraint stress significantly reduced the number of SNc dopaminergic neurons in Il13ra1 Y/+ mice. Neuronal loss at 16 weeks was significantly lower in Il13ra1 Y/- mice. However, the loss of dopaminergic neurons measured at 20 weeks, after 4 weeks of non-stress following the 16 weeks of stress, was similar in Il13ra1 Y/+ and Il13ra1 Y/- mice. CONCLUSIONS: IL-13, a cytokine previously demonstrated to increase the susceptibility of SNc dopaminergic neurons to oxidative stress, is elevated in the SN by restraint stress. Lack of IL-13Rα1 did not prevent nor halted but delayed neuronal loss in the mouse model of chronic restraint stress. IL-13/IL-13Rα1 may represent a target to reduce the rate of DA neuronal loss that can occur during severe chronic restraint stress.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Subunidade alfa1 de Receptor de Interleucina-13/deficiência , Estresse Oxidativo/fisiologia , Estresse Psicológico/metabolismo , Animais , Contagem de Células/métodos , Neurônios Dopaminérgicos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estresse Psicológico/patologia , Substância Negra/metabolismo , Substância Negra/patologia
18.
J Am Chem Soc ; 136(31): 10996-1001, 2014 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-25051503

RESUMO

2,2',7,7'-Tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD), the prevalent organic hole transport material used in solid-state dye-sensitized solar cells and perovskite-absorber solar cells, relies on an uncontrolled oxidative process to reach appreciable conductivity. This work presents the use of a dicationic salt of spiro-OMeTAD, named spiro(TFSI)2, as a facile means of controllably increasing the conductivity of spiro-OMeTAD up to 10(-3) S cm(-1) without relying on oxidation in air. Spiro(TFSI)2 enables the first demonstration of solid-state dye-sensitized solar cells fabricated and operated with the complete exclusion of oxygen after deposition of the sensitizer with higher and more reproducible device performance. Perovskite-absorber solar cells fabricated with spiro(TFSI)2 show improved operating stability in an inert atmosphere. Gaining control of the conductivity of the HTM in both dye-sensitized and perovskite-absorber solar cells in an inert atmosphere using spiro(TFSI)2 is an important step toward the commercialization of these technologies.

19.
Nat Biotechnol ; 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273065

RESUMO

The utility of genetically encoded biosensors for sensing the activity of signaling proteins has been hampered by a lack of strategies for matching sensor sensitivity to the physiological concentration range of the target. Here we used computational protein design to generate intracellular sensors of Ras activity (LOCKR-based Sensor for Ras activity (Ras-LOCKR-S)) and proximity labelers of the Ras signaling environment (LOCKR-based, Ras activity-dependent Proximity Labeler (Ras-LOCKR-PL)). These tools allow the detection of endogenous Ras activity and labeling of the surrounding environment at subcellular resolution. Using these sensors in human cancer cell lines, we identified Ras-interacting proteins in oncogenic EML4-Alk granules and found that Src-Associated in Mitosis 68-kDa (SAM68) protein specifically enhances Ras activity in the granules. The ability to subcellularly localize endogenous Ras activity should deepen our understanding of Ras function in health and disease and may suggest potential therapeutic strategies.

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