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1.
Cell ; 181(7): 1518-1532.e14, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32497502

RESUMO

The rise of antibiotic resistance and declining discovery of new antibiotics has created a global health crisis. Of particular concern, no new antibiotic classes have been approved for treating Gram-negative pathogens in decades. Here, we characterize a compound, SCH-79797, that kills both Gram-negative and Gram-positive bacteria through a unique dual-targeting mechanism of action (MoA) with undetectably low resistance frequencies. To characterize its MoA, we combined quantitative imaging, proteomic, genetic, metabolomic, and cell-based assays. This pipeline demonstrates that SCH-79797 has two independent cellular targets, folate metabolism and bacterial membrane integrity, and outperforms combination treatments in killing methicillin-resistant Staphylococcus aureus (MRSA) persisters. Building on the molecular core of SCH-79797, we developed a derivative, Irresistin-16, with increased potency and showed its efficacy against Neisseria gonorrhoeae in a mouse vaginal infection model. This promising antibiotic lead suggests that combining multiple MoAs onto a single chemical scaffold may be an underappreciated approach to targeting challenging bacterial pathogens.


Assuntos
Bactérias Gram-Negativas/efeitos dos fármacos , Pirróis/metabolismo , Pirróis/farmacologia , Quinazolinas/metabolismo , Quinazolinas/farmacologia , Animais , Antibacterianos/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Feminino , Ácido Fólico/metabolismo , Bactérias Gram-Positivas/efeitos dos fármacos , Células HEK293 , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Ovariectomia , Proteômica , Pseudomonas aeruginosa/efeitos dos fármacos
2.
Blood ; 139(4): 538-553, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-34624079

RESUMO

Burkitt lymphoma (BL) is an aggressive lymphoma type that is currently treated by intensive chemoimmunotherapy. Despite the favorable clinical outcome for most patients with BL, chemotherapy-related toxicity and disease relapse remain major clinical challenges, emphasizing the need for innovative therapies. Using genome-scale CRISPR-Cas9 screens, we identified B-cell receptor (BCR) signaling, specific transcriptional regulators, and one-carbon metabolism as vulnerabilities in BL. We focused on serine hydroxymethyltransferase 2 (SHMT2), a key enzyme in one-carbon metabolism. Inhibition of SHMT2 by either knockdown or pharmacological compounds induced anti-BL effects in vitro and in vivo. Mechanistically, SHMT2 inhibition led to a significant reduction of intracellular glycine and formate levels, which inhibited the mTOR pathway and thereby triggered autophagic degradation of the oncogenic transcription factor TCF3. Consequently, this led to a collapse of tonic BCR signaling, which is controlled by TCF3 and is essential for BL cell survival. In terms of clinical translation, we also identified drugs such as methotrexate that synergized with SHMT inhibitors. Overall, our study has uncovered the dependency landscape in BL, identified and validated SHMT2 as a drug target, and revealed a mechanistic link between SHMT2 and the transcriptional master regulator TCF3, opening up new perspectives for innovative therapies.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/metabolismo , Glicina Hidroximetiltransferase/antagonistas & inibidores , Glicina Hidroximetiltransferase/metabolismo , Animais , Linfoma de Burkitt/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Descoberta de Drogas , Formiatos/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Glicina/metabolismo , Glicina Hidroximetiltransferase/genética , Humanos , Camundongos , Terapia de Alvo Molecular , Proteólise/efeitos dos fármacos
3.
Cerebrovasc Dis ; 52(2): 153-159, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35908539

RESUMO

INTRODUCTION: Early recognition and risk stratification of cardiovascular events are necessary in patients after ischemic stroke. Recent evidence suggests that elevated high-sensitive cardiac troponin is a predictor of mortality and vascular events. Therefore, we aimed to explore the prognostic role of high-sensitive cardiac troponin I (hs-TnI) on mortality and cardiovascular outcomes in patients after ischemic stroke. METHODS: From August 2014 to July 2017, 1,506 patients with acute ischemic stroke were pulled consecutively in a retrospective single-center registry. Of these, 1,019 patients were selected and classified into the elevated or non-elevated hs-TnI groups according to hs-TnI level of 99th percentile upper reference limit (URL) at the time of admission for ischemic stroke. The primary outcome was a major adverse cardiac and cerebrovascular event (MACCE) during follow-up. RESULTS: Among 1,019 patients, 708 patients were non-elevated hs-TnI group (<99th percentile URL of hs-TnI) and 311 patients were elevated hs-TnI group (≥99th percentile URL of hs-TnI). The median follow-up period was 22.5 (interquartile range 5.0-38.8) months. In a multivariable Cox regression model, the elevated hs-TnI group has a higher risk of MACCE (adjusted hazard ratio [HR]: 3.12; 95% confidence interval [CI]: 2.33-4.17; p < 0.01), all-cause mortality (adjusted HR: 4.15; 95% CI: 2.47-6.99; p < 0.01) and readmission caused by coronary revascularization (adjusted HR: 3.12; 95% CI: 1.41-6.90; p < 0.01), heart failure (adjusted HR: 2.76; 95% CI: 1.38-5.51; p < 0.01), and stroke (adjusted HR: 1.73; 95% CI: 1.07-2.78; p = 0.02) compared with the non-elevated hs-TnI group. CONCLUSIONS: Elevated hs-TnI is independently associated with higher mortality and cardiac and cerebrovascular events in patients with ischemic stroke and may serve as a valuable prognostic factor in management after ischemic stroke.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Troponina I , Estudos Retrospectivos , Prognóstico , Biomarcadores , Troponina T
4.
Nat Chem Biol ; 16(7): 731-739, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32393898

RESUMO

Glucose is catabolized by two fundamental pathways, glycolysis to make ATP and the oxidative pentose phosphate pathway to make reduced nicotinamide adenine dinucleotide phosphate (NADPH). The first step of the oxidative pentose phosphate pathway is catalyzed by the enzyme glucose-6-phosphate dehydrogenase (G6PD). Here we develop metabolite reporter and deuterium tracer assays to monitor cellular G6PD activity. Using these, we show that the most widely cited G6PD antagonist, dehydroepiandosterone, does not robustly inhibit G6PD in cells. We then identify a small molecule (G6PDi-1) that more effectively inhibits G6PD. Across a range of cultured cells, G6PDi-1 depletes NADPH most strongly in lymphocytes. In T cells but not macrophages, G6PDi-1 markedly decreases inflammatory cytokine production. In neutrophils, it suppresses respiratory burst. Thus, we provide a cell-active small molecule tool for oxidative pentose phosphate pathway inhibition, and use it to identify G6PD as a pharmacological target for modulating immune response.


Assuntos
Inibidores Enzimáticos/farmacologia , Glucosefosfato Desidrogenase/antagonistas & inibidores , Linfócitos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Via de Pentose Fosfato/efeitos dos fármacos , Animais , Linhagem Celular , Desidroepiandrosterona/farmacologia , Relação Dose-Resposta a Droga , Ensaios Enzimáticos , Glucose/metabolismo , Glucosefosfato Desidrogenase/imunologia , Glucosefosfato Desidrogenase/metabolismo , Glicólise/imunologia , Células HCT116 , Células Hep G2 , Humanos , Imunidade Inata , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/citologia , Linfócitos/enzimologia , Linfócitos/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/citologia , Macrófagos/enzimologia , Macrófagos/imunologia , NADP/antagonistas & inibidores , NADP/metabolismo , Neutrófilos/citologia , Neutrófilos/enzimologia , Neutrófilos/imunologia , Via de Pentose Fosfato/imunologia
5.
Int J Mol Sci ; 23(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36142661

RESUMO

Post-stroke cognitive impairment is one of the most common complications in stroke survivors. Concomitant vascular risk factors, including aging, diabetes mellitus, hypertension, dyslipidemia, or underlying pathologic conditions, such as chronic cerebral hypoperfusion, white matter hyperintensities, or Alzheimer's disease pathology, can predispose patients to develop post-stroke dementia (PSD). Given the various clinical conditions associated with PSD, a single animal model for PSD is not possible. Animal models of PSD that consider these diverse clinical situations have not been well-studied. In this literature review, diverse rodent models that simulate the various clinical conditions of PSD have been evaluated. Heterogeneous rodent models of PSD are classified into the following categories: surgical technique, special structure, and comorbid condition. The characteristics of individual models and their clinical significance are discussed in detail. Diverse rodent models mimicking the specific pathomechanisms of PSD could provide effective animal platforms for future studies investigating the characteristics and pathophysiology of PSD.


Assuntos
Isquemia Encefálica , Demência , Acidente Vascular Cerebral , Animais , Isquemia Encefálica/complicações , Demência/patologia , Fatores de Risco , Roedores , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/patologia
6.
Int J Mol Sci ; 23(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36498940

RESUMO

Sleep is a restorative period that plays a crucial role in the physiological functioning of the body, including that of the immune system, memory processing, and cognition. Sleep disturbances can be caused by various physical, mental, and social problems. Recently, there has been growing interest in sleep. Maydis stigma (MS, corn silk) is a female maize flower that is traditionally used as a medicinal plant to treat many diseases, including hypertension, edema, and diabetes. It is also used as a functional food in tea and other supplements. ß-Sitosterol (BS) is a phytosterol and a natural micronutrient in higher plants, and it has a similar structure to cholesterol. It is a major component of MS and has anti-inflammatory, antidepressive, and sedative effects. However, the potential effects of MS on sleep regulation remain unclear. Here, we investigated the effects of MS on sleep in mice. The effects of MS on sleep induction were determined using pentobarbital-induced sleep and caffeine-induced sleep disruption mouse models. MS extracts decreased sleep latency and increased sleep duration in both the pentobarbital-induced sleep induction and caffeine-induced sleep disruption models compared to the positive control, valerian root extract. The butanol fraction of MS extracts decreased sleep latency time and increased sleep duration. In addition, ß-sitosterol enhances sleep latency and sleep duration. Both MS extract and ß-sitosterol increased alpha activity in the EEG analysis. We measured the mRNA expression of melatonin receptors 1 and 2 (MT1/2) using qRT-PCR. The mRNA expression of melatonin receptors 1 and 2 was increased by MS extract and ß-sitosterol treatment in rat primary cultured neurons and the brain. In addition, MS extract increased the expression of clock genes including per1/2, cry1/2, and Bmal1 in the brain. MS extract and ß-sitosterol increased the phosphorylation of ERK1/2 and αCaMKII. Our results demonstrate for the first time that MS has a sleep-promoting effect via melatonin receptor expression, which may provide new scientific evidence for its use as a potential therapeutic agent for the treatment and prevention of sleep disturbance.


Assuntos
Extratos Vegetais , Transtornos do Sono-Vigília , Ratos , Camundongos , Animais , Receptores de Melatonina , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química , Transtornos do Sono-Vigília/tratamento farmacológico , Sono , RNA Mensageiro
7.
J Geriatr Psychiatry Neurol ; 34(6): 565-573, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-32912058

RESUMO

OBJECTIVE: The efficacy of antidepressants in post-stroke depressive symptoms (PSD) varies. We aimed to examine whether the effect of escitalopram on PSD differs according to individual depressive symptoms and stroke lesion location. METHODS: This is a post hoc analysis of EMOTION (ClinicalTrials.gov, NCT01278498), a randomized, placebo-controlled, double-blind trial that examined the efficacy of escitalopram on depression in acute stroke patients (237 with placebo, 241 with escitalopram). Depressive symptoms were evaluated with the 10-item Montgomery-Åsberg Depression Rating Scale (MADRS). Changes in MADRS and individual item scores at 12 weeks were compared between the treatment groups and among the stroke lesion location groups. Stroke lesion locations were grouped according to the anatomical distribution of serotonin fibers that originate from the midbrain/pons and spread to the forebrain via subcortical structures: "Midbrain-Pons," "Frontal-Subcortical," and "Others." Least-squares means were calculated to demonstrate the independent effect of lesion location. RESULTS: Total MADRS scores decreased more significantly in the escitalopram than in the placebo group, while a significant effect of escitalopram was observed in only 3 items: apparent sadness, reported sadness, pessimistic thoughts. In the lesion location analyses, escitalopram users in the Frontal-Subcortical group showed significant improvement in total MADRS scores (placebo [n = 130] vs. escitalopram [n = 148], least-square mean [95% CI]: -2.3 [-3.5 to -0.2] vs. -4.5 [-5.5 to -3.4], p = .005), while those in the Midbrain-Pons and Others groups did not. CONCLUSIONS: The effect of escitalopram on PSD may be more prominent in patients with particular depressive symptoms and stroke lesion locations, suggesting the need for tailored treatment strategies.


Assuntos
Transtorno Depressivo Maior , Acidente Vascular Cerebral , Citalopram/uso terapêutico , Depressão/tratamento farmacológico , Depressão/etiologia , Método Duplo-Cego , Escitalopram , Humanos , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Resultado do Tratamento
8.
Stroke ; 51(3): 931-937, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31856691

RESUMO

Background and Purpose- Although cilostazol has shown less hemorrhagic events than aspirin, only marginal difference was observed in hemorrhagic stroke events among patients at high risk for cerebral hemorrhage. To identify patients who would most benefit from cilostazol, this study analyzed interactions between treatment and subgroups of the PICASSO trial (Prevention of Cardiovascular Events in Asian Ischemic Stroke Patients With High Risk of Cerebral Hemorrhage). Methods- Ischemic stroke patients with a previous intracerebral hemorrhage or multiple microbleeds were randomized to treatment with cilostazol or aspirin and followed up for a mean 1.8 years. Efficacy, defined as the composite of any stroke, myocardial infarction, and vascular death, and safety, defined as the incidence of hemorrhagic stroke, were analyzed in the 2 groups. Interactions between treatment and age, sex, presence of hypertension and diabetes mellitus, index of high-risk cerebral hemorrhage, and white matter lesion burden were analyzed for primary and key secondary outcomes. Changes in vital signs and laboratory results were compared in the 2 groups. Results- Among all 1534 patients enrolled, a significant interaction between treatment group and index of high risk for cerebral hemorrhage on hemorrhagic stroke (P for interaction, 0.03) was observed. Hemorrhagic stroke was less frequent in the cilostazol than in the aspirin group in patients with multiple microbleeds (1 versus 13 events; hazard ratio, 0.08 [95% CI, 0.01-0.61]; P=0.01). A marginal interaction between treatment group and white matter change on any stroke (P for interaction, 0.08) was observed. Cilostazol reduced any stroke significantly in patients with mild (5 versus 16 events; hazard ratio, 0.36 [95% CI, 0.13-0.97]; P=0.04)-to-moderate (16 versus 32 events; hazard ratio, 0.50 [95% CI, 0.29-0.92]; P=0.03) white matter changes. Heart rate and HDL (high-density lipoprotein) cholesterol level were significantly higher in the cilostazol group than in the aspirin group at follow-up. Conclusions- Cilostazol may be more beneficial for ischemic stroke patients with multiple cerebral microbleeds and before white matter changes are extensive. Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT01013532.


Assuntos
Aspirina/administração & dosagem , Isquemia Encefálica/tratamento farmacológico , Hemorragia Cerebral/tratamento farmacológico , Cilostazol/administração & dosagem , Acidente Vascular Cerebral/tratamento farmacológico , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
9.
Cerebrovasc Dis ; 49(1): 19-25, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32023608

RESUMO

BACKGROUND: We aimed to examine sex differences in symptom characteristics and pharmacological responses in post-stroke depressive (PSD) symptoms. METHODS: This is a post hoc analysis of EMOTION (ClinicalTrials.gov, NCT01278498), a randomized, placebo-controlled, double-blind trial that examined the efficacy of escitalopram for 3 months on depression in patients with acute stroke. Depressive symptoms were evaluated using the 10-item Montgomery-Åsberg Depression Rating Scale (MADRS). Baseline characteristics, clinical variables, and treatment responses to escitalopram were compared between male and female patients. Treatment responses were defined as changes in MADRS (total score and its components) between baseline and 3 months and were compared between the escitalopram and placebo groups within each sex group. The least square mean was calculated to determine the independent effect of escitalopram, of which interaction was evaluated with patient sex. RESULTS: Of the 478 patients (intention-to-treat population), 187 (39%) were female. Female patients were significantly older than male patients and demonstrated more severe depressive symptoms at baseline (male vs. female, MADRS score, mean [SD]: 9.7 ± 8.0 vs. 12.2 ± 8.4, p = 0.001), especially in apparent sadness, reported sadness, and reduced appetite items. These differences were significant after adjustment for age and the severity of neurologic deficits. The female escitalopram group showed a significant 3-month improvement in MADRS scores (placebo [n = 86] vs. escitalopram [n = 101], least square mean [95% CI] -2.7 [-4.1 to -1.2] vs. -5.0 [-6.4 to -3.6], p = 0.007), and this efficacy was prominent in apparent sadness, reported sadness, and pessimistic thoughts items. However, there was no significant effect of escitalopram on depressive symptoms in the male group. The treatment responses of escitalopram tended to be more pronounced in the female group, particularly in alleviating a subset of depressive symptoms such as apparent sadness (p for interaction = 0.009). CONCLUSION: PSD may differ according to sex in its symptom characteristics and treatment responses to escitalopram, and tailored treatment strategies for PSD may therefore be needed.


Assuntos
Afeto/efeitos dos fármacos , Antidepressivos de Segunda Geração/uso terapêutico , Citalopram/uso terapêutico , Depressão/tratamento farmacológico , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Acidente Vascular Cerebral/complicações , Idoso , Idoso de 80 Anos ou mais , Depressão/diagnóstico , Depressão/etiologia , Depressão/psicologia , Método Duplo-Cego , Feminino , Disparidades nos Níveis de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia , Fatores de Risco , Fatores Sexuais , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/psicologia , Fatores de Tempo , Resultado do Tratamento
10.
Can J Neurol Sci ; 47(2): 242-244, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31657289

RESUMO

Migraine with aura is one of the causes of stroke mimics. We retrospectively reviewed the 10-year medical records of patients who were treated with acute stroke management protocol. We analyzed the frequency and characteristics of patients with a final diagnosis of migraine with aura. Among the 1355 patients with stroke mimics, migraine with aura was the final diagnosis in 36 patients (2.7%). The most common auras included sensory and brainstem auras followed by motor, visual, and speech/language auras. One patient manifested transient atrial fibrillation during the migraine attack, which can be a link with acute stroke.


Assuntos
Enxaqueca com Aura/diagnóstico , Acidente Vascular Cerebral/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Enxaqueca com Aura/epidemiologia , Sistema de Registros , Estudos Retrospectivos , Acidente Vascular Cerebral/epidemiologia
11.
Proc Natl Acad Sci U S A ; 114(43): 11404-11409, 2017 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-29073064

RESUMO

The enzyme serine hydroxymethyltransferse (SHMT) converts serine into glycine and a tetrahydrofolate-bound one-carbon unit. Folate one-carbon units support purine and thymidine synthesis, and thus cell growth. Mammals have both cytosolic SHMT1 and mitochondrial SHMT2, with the mitochondrial isozyme strongly up-regulated in cancer. Here we show genetically that dual SHMT1/2 knockout blocks HCT-116 colon cancer tumor xenograft formation. Building from a pyrazolopyran scaffold that inhibits plant SHMT, we identify small-molecule dual inhibitors of human SHMT1/2 (biochemical IC50 ∼ 10 nM). Metabolomics and isotope tracer studies demonstrate effective cellular target engagement. A cancer cell-line screen revealed that B-cell lines are particularly sensitive to SHMT inhibition. The one-carbon donor formate generally rescues cells from SHMT inhibition, but paradoxically increases the inhibitor's cytotoxicity in diffuse large B-cell lymphoma (DLBCL). We show that this effect is rooted in defective glycine uptake in DLBCL cell lines, rendering them uniquely dependent upon SHMT enzymatic activity to meet glycine demand. Thus, defective glycine import is a targetable metabolic deficiency of DLBCL.


Assuntos
Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Glicina Hidroximetiltransferase/antagonistas & inibidores , Glicina/metabolismo , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/metabolismo , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Inibidores Enzimáticos/química , Feminino , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Modelos Moleculares , Estrutura Molecular , Neoplasias Experimentais/metabolismo , Conformação Proteica
12.
Int J Mol Sci ; 21(18)2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32967251

RESUMO

Post-stroke dementia (PSD) is a major neurodegenerative consequence of stroke. Tauopathy has been reported in diverse neurodegenerative diseases. We investigated the cognitive impairment and pathomechanism associated with tauopathy in a rat model of PSD by modeling acute ischemic stroke and underlying chronic cerebral hypoperfusion (CCH). We performed middle cerebral artery occlusion (MCAO) surgery in rats to mimic acute ischemic stroke, followed by bilateral common carotid artery occlusion (BCCAo) surgery to mimic CCH. We performed behavioral tests and focused on the characterization of tauopathy through histology. Parenchymal infiltration of cerebrospinal fluid (CSF) tracers after intracisternal injection was examined to evaluate glymphatic function. In an animal model of PSD, cognitive impairment was aggravated when BCCAo was combined with MCAO. Tauopathy, manifested by tau hyperphosphorylation, was prominent in the peri-infarct area when CCH was combined. Synergistic accentuation of tauopathy was evident in the white matter. Microtubules in the neuronal axon and myelin sheath showed partial colocalization with the hyperphosphorylated tau, whereas oligodendrocytes showed near-complete colocalization. Parenchymal infiltration of CSF tracers was attenuated in the PSD model. Our experimental results suggest a hypothesis that CCH may aggravate cognitive impairment and tau hyperphosphorylation in a rat model of PSD by interfering with tau clearance through the glymphatic system. Therapeutic strategies to improve the clearance of brain metabolic wastes, including tau, may be a promising approach to prevent PSD after stroke.


Assuntos
Infarto Encefálico , Demência , Acidente Vascular Cerebral , Tauopatias , Animais , Infarto Encefálico/complicações , Infarto Encefálico/metabolismo , Infarto Encefálico/patologia , Infarto Encefálico/fisiopatologia , Demência/etiologia , Demência/metabolismo , Demência/patologia , Demência/fisiopatologia , Modelos Animais de Doenças , Masculino , Aprendizagem em Labirinto , Ratos , Ratos Wistar , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/fisiopatologia , Tauopatias/etiologia , Tauopatias/metabolismo , Tauopatias/patologia , Tauopatias/fisiopatologia
13.
Am J Emerg Med ; 37(10): 1871-1875, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30598373

RESUMO

BACKGROUND: Although seizure is one of the common causes of stroke mimics and can be an initial manifestation of acute stroke, accurate diagnosis of seizure during acute stroke management is frequently difficult. The objective of this study was to analyze the frequency, characteristics and results of neuroimaging including CT perfusion in patients with seizures manifesting initially as stroke-like symptoms. METHODS: We retrospectively reviewed the medical records of patients who were treated with code stroke alarming system. We studied the frequency and characteristics of patients who were finally diagnosed with seizures and further correlated their clinical features with the results of neuroimaging including CT perfusion. RESULTS: Among the 4673 patients who were treated with code stroke alarming system, seizure was the third most frequent diagnosis (188 patients, 4.0%) among the causes of stroke mimics including 27 patients who manifested seizure as an initial manifestation of acute stroke. CT perfusion showed perfusion changes in more than 25% of them (49 of 188 patients, 26.1%). Thrombolysis was not performed in six patients who presented with seizure as an initial presentation of stroke for delayed diagnosis while one patient underwent thrombolysis for misdiagnosis of seizure. CONCLUSIONS: Seizure is a frequent final diagnosis in acute stroke management. However, careful interpretation of clinical features and results of perfusion imaging is necessary to avoid unnecessary thrombolysis in patients with seizure as a stroke mimic and thrombolysis failure due to delayed diagnosis of seizure as an initial manifestation of stroke.


Assuntos
Convulsões/diagnóstico , Acidente Vascular Cerebral/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Tardio , Diagnóstico Diferencial , Erros de Diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem , Estudos Retrospectivos , Convulsões/etiologia , Acidente Vascular Cerebral/complicações , Tomografia Computadorizada por Raios X
14.
Int J Mol Sci ; 20(24)2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31888302

RESUMO

To investigate the changes in the expression of specific genes that occur during the acute-to-chronic post-stroke phase, we identified differentially expressed genes (DEGs) between naive cortical tissues and peri-infarct tissues at 1, 4, and 8 weeks after photothrombotic stroke. The profiles of DEGs were subjected to the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and gene ontology analyses, followed by string analysis of the protein-protein interactions (PPI) of the products of these genes. We found 3771, 536, and 533 DEGs at 1, 4, and 8 weeks after stroke, respectively. A marked decrease in biological-process categories, such as brain development and memory, and a decrease in neurotransmitter synaptic and signaling pathways were observed 1 week after stroke. The PPI analysis showed the downregulation of Dlg4, Bdnf, Gria1, Rhoa, Mapk8, and glutamatergic receptors. An increase in biological-process categories, including cell population proliferation, cell adhesion, and inflammatory responses, was detected at 4 and 8 weeks post-stroke. The KEGG pathways of complement and coagulation cascades, phagosomes, antigen processing, and antigen presentation were also altered. CD44, C1, Fcgr2b, Spp1, and Cd74 occupied a prominent position in network analyses. These time-dependent changes in gene profiles reveal the unique pathophysiological characteristics of stroke and suggest new therapeutic targets for this disease.


Assuntos
Isquemia Encefálica/genética , Encéfalo/patologia , Acidente Vascular Cerebral/genética , Transcriptoma/genética , Animais , Isquemia Encefálica/complicações , Ontologia Genética , Masculino , Mapas de Interação de Proteínas/genética , Ratos Wistar , Acidente Vascular Cerebral/complicações , Trombose/complicações , Fatores de Tempo
15.
J Biol Chem ; 292(10): 4064-4076, 2017 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-28119451

RESUMO

Quorum sensing is a process of cell-cell communication that bacteria use to regulate collective behaviors. Quorum sensing depends on the production, detection, and group-wide response to extracellular signal molecules called autoinducers. In many bacterial species, quorum sensing controls virulence factor production. Thus, disrupting quorum sensing is considered a promising strategy to combat bacterial pathogenicity. Several members of a family of naturally produced plant metabolites called flavonoids inhibit Pseudomonas aeruginosa biofilm formation by an unknown mechanism. Here, we explore this family of molecules further, and we demonstrate that flavonoids specifically inhibit quorum sensing via antagonism of the autoinducer-binding receptors, LasR and RhlR. Structure-activity relationship analyses demonstrate that the presence of two hydroxyl moieties in the flavone A-ring backbone are essential for potent inhibition of LasR/RhlR. Biochemical analyses reveal that the flavonoids function non-competitively to prevent LasR/RhlR DNA binding. Administration of the flavonoids to P. aeruginosa alters transcription of quorum sensing-controlled target promoters and suppresses virulence factor production, confirming their potential as anti-infectives that do not function by traditional bacteriocidal or bacteriostatic mechanisms.


Assuntos
Proteínas de Bactérias/antagonistas & inibidores , Flavonoides/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Percepção de Quorum/fisiologia , Transativadores/antagonistas & inibidores , Virulência/efeitos dos fármacos , Regulação Alostérica , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Pseudomonas aeruginosa/crescimento & desenvolvimento , Percepção de Quorum/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-Atividade
16.
Biochem Biophys Res Commun ; 495(1): 1214-1220, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29180007

RESUMO

The high concentrations of nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) in activated glial cells in response to neuroinflammatory stimuli have neurotoxic effects on the brain. At basal levels, iNOS expression is low, and proinflammatory stimuli induce iNOS expression in astrocytes, microglia, and oligodendrocytes. Fyn, a non-receptor tyrosine kinase, regulates iNOS expression in several types of immune cells. However, its role in stimulated astrocytes is less clear. In this study, we investigated the role of Fyn in the regulation of lipopolysaccharide (LPS)-induced iNOS expression in astrocytes from mice and rats. Intracerebroventricular LPS injections in cortical regions enhanced iNOS mRNA and protein levels, which were increased in Fyn-deficient mice. Accordingly, LPS-induced nitrite production was enhanced in primary astrocytes cultured from Fyn-deficient mice or rats. Similar results were observed in cultured astrocytes after the siRNA-induced knockdown of Fyn expression. Finally, we observed increased LPS-induced extracellular signal-regulated protein kinase (ERK) activation in Fyn-deficient astrocytes. These results suggested that Fyn has a regulatory role in iNOS expression in astrocytes during neuroinflammatory responses.


Assuntos
Astrócitos/imunologia , MAP Quinases Reguladas por Sinal Extracelular/imunologia , Regulação Enzimológica da Expressão Gênica/imunologia , Mediadores da Inflamação/imunologia , Lipopolissacarídeos/farmacologia , Óxido Nítrico Sintase Tipo II/imunologia , Proteínas Proto-Oncogênicas c-fyn/imunologia , Animais , Astrócitos/efeitos dos fármacos , Células Cultivadas , Sistema de Sinalização das MAP Quinases/imunologia , Camundongos , Camundongos Knockout , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
17.
J Neurol Neurosurg Psychiatry ; 89(3): 271-276, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29030421

RESUMO

OBJECTIVE: Selective serotonin reuptake inhibitors (SSRIs) putatively improve neurological recovery after stroke. We aimed to investigate whether serotonin transporter (SERT) gene polymorphisms are related to the responsiveness to SSRIs in the poststroke neurological recovery. METHODS: This was a post hoc analysis of the EMOTION study (ClinicalTrials.gov NCT01278498), a randomised, placebo-controlled, double-blind trial examining the efficacy of escitalopram on emotional and neurological disturbances after acute stroke. Patients with no/minimal disability initially (modified Rankin Scale (mRS) 0-1) were excluded. Of the participants, 301 underwent genetic studies of the STin2 (a variable number tandem repeat (VNTR) in intron 2) (STin2 12/10 and STin2 12/12 genotypes) and 5-HTTLPR (a variable-length repeat in the promoter region) polymorphisms of SERT. We explored whether neurological function (National Institutes of Health Stroke Scale (NIHSS) score and mRS) at 3 months would differ according to SERT polymorphisms within each treatment arm (escitalopram and placebo). RESULTS: Among the escitalopram users (n=159), neurological function in subjects with STin2 12/10 (n=29) improved significantly more than that in STin2 12/12 carriers (n=130) at 3 months. After adjusting for age, initial NIHSS and depression, STin2 12/10 independently predicted a good clinical outcome (mRS 0-1) (OR 2.99, 95% CI 1.04 to 8.58) at 3 months. However, differences between STin2 polymorphisms were not shown in the placebo group (n=142). 5-HTTLPR polymorphisms were not associated with neurological recovery in any treatment group. CONCLUSION: STin2 VNTR polymorphisms may be associated with poststroke neurological recovery after SSRI therapy. Further studies are needed to identify the role of serotonin in neurological recovery after stroke.


Assuntos
Citalopram/uso terapêutico , Variantes Farmacogenômicos , Recuperação de Função Fisiológica/genética , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Acidente Vascular Cerebral/tratamento farmacológico , Idoso , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/psicologia
18.
Eur Neurol ; 80(1-2): 42-49, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30205365

RESUMO

BACKGROUND: Transient global amnesia (TGA) is an interesting clinical syndrome characterized by sudden memory loss for recent events and an inability to retain new memories usually lasting several hours and recovering spontaneously. We conducted a literature search of medical procedure-related TGA and its predisposing conditions. METHODS: We performed PubMed searches using the keyword "transient global amnesia" combined with "procedure," "test," "therapy," or various other individual medical procedures. In addition, we described 2 cases of gastroscopy-related TGA. RESULTS: Eighty-nine patients with medical procedure-related TGA in 49 articles were summarized. The most common procedure was cerebral angiography (n = 45), followed by coronary angiography (n = 10) and general anesthesia (n = 9). After categorization, neurological procedures were most common (n = 46, 51.7%), followed by cardiac (n = 17, 19.1%), anesthetic (n = 11, 12.4%), gastrointestinal (n = 4, 4.5%), and pulmonary (n = 2, 2.2%) procedures. CONCLUSIONS: Diverse cases of medical procedure-related TGA have been reported in the literature. Valsalva-associated activities, emotional stress with anxiety, and acute pain were predisposing conditions. An understanding of medical procedure-related TGA may be important for clinicians who perform such medical procedures.


Assuntos
Amnésia Global Transitória/etiologia , Técnicas e Procedimentos Diagnósticos/efeitos adversos , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Adulto , Amnésia Global Transitória/epidemiologia , Ansiedade/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Eur Neurol ; 80(1-2): 106-114, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30347393

RESUMO

Although statins are established therapy for the secondary prevention of ischemic stroke, factors associated with adherence to statin treatment following ischemic stroke are not well known. To address this, we assessed the 6-month statin adherence using 8-item Morisky Medication Adherence Scale-8 in patients with acute ischemic stroke. Of 991 patients, 65.6% were adherent to statin at 6-month after discharge. Multiple logistic regression analysis showed that patients' awareness of hyperlipidemia (OR 1.62; 95% CI 1.07-2.43), large artery stroke subtype (versus non-large artery stroke, OR 1.79; 95% CI 1.19-2.68), and alcohol drinking habits (OR 1.64; 95% CI 1.06-2.53) were positively associated, while high statin dose (versus low dose, OR 0.6; 95% CI 0.40-0.90) and higher daily number of medication pills (OR 0.93; 95% CI 0.88-0.97) were found to have a negative association with self-reported good adherence to statin medication after acute ischemic stroke. However, stroke severity and diagnosis of hyperlipidemia were not associated with adherence. These results suggest that educational and motivational interventions may enhance statin adherence because modifiable factors were associated with statin adherence.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Adesão à Medicação/estatística & dados numéricos , Prevenção Secundária/métodos , Acidente Vascular Cerebral/prevenção & controle , Idoso , Feminino , Humanos , Hiperlipidemias/complicações , Hiperlipidemias/tratamento farmacológico , Masculino , Pessoa de Meia-Idade
20.
Int J Mol Sci ; 19(7)2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29997355

RESUMO

To develop new rehabilitation therapies for chronic stroke, this study examined the effectiveness of task-specific training (TST) and TST combined with DNA methyltransferase inhibitor in chronic stroke recovery. Eight weeks after photothrombotic stroke, 5-Aza-2'-deoxycytidine (5-Aza-dC) infusion was done on the contralesional cortex for four weeks, with and without TST. Functional recovery was assessed using the staircase test, the cylinder test, and the modified neurological severity score (mNSS). Axonal plasticity and expression of brain-derived neurotrophic factor (BDNF) were determined in the contralateral motor cortex. TST and TST combined with 5-Aza-dC significantly improved the skilled reaching ability in the staircase test and ameliorated mNSS scores and cylinder test performance. TST and TST with 5-Aza-dC significantly increased the crossing fibers from the contralesional red nucleus, reticular formation in medullar oblongata, and dorsolateral spinal cord. Mature BDNF was significantly upregulated by TST and TST combined with 5-Azd-dC. Functional recovery after chronic stroke may involve axonal plasticity and increased mature BDNF by modulating DNA methylation in the contralesional cortex. Our results suggest that combined therapy to enhance axonal plasticity based on TST and 5-Aza-dC constitutes a promising approach for promoting the recovery of function in the chronic stage of stroke.


Assuntos
Azacitidina/análogos & derivados , Metilação de DNA/efeitos dos fármacos , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/terapia , Animais , Axônios/metabolismo , Azacitidina/administração & dosagem , Azacitidina/farmacologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Decitabina , Modelos Animais de Doenças , Exercício Físico , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Plasticidade Neuronal , Ratos , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/fisiopatologia , Análise e Desempenho de Tarefas
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