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1.
Nature ; 585(7824): 303-308, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32879488

RESUMO

Most general anaesthetics and classical benzodiazepine drugs act through positive modulation of γ-aminobutyric acid type A (GABAA) receptors to dampen neuronal activity in the brain1-5. However, direct structural information on the mechanisms of general anaesthetics at their physiological receptor sites is lacking. Here we present cryo-electron microscopy structures of GABAA receptors bound to intravenous anaesthetics, benzodiazepines and inhibitory modulators. These structures were solved in a lipidic environment and are complemented by electrophysiology and molecular dynamics simulations. Structures of GABAA receptors in complex with the anaesthetics phenobarbital, etomidate and propofol reveal both distinct and common transmembrane binding sites, which are shared in part by the benzodiazepine drug diazepam. Structures in which GABAA receptors are bound by benzodiazepine-site ligands identify an additional membrane binding site for diazepam and suggest an allosteric mechanism for anaesthetic reversal by flumazenil. This study provides a foundation for understanding how pharmacologically diverse and clinically essential drugs act through overlapping and distinct mechanisms to potentiate inhibitory signalling in the brain.


Assuntos
Anestésicos Gerais/química , Anestésicos Gerais/farmacologia , Barbitúricos/química , Barbitúricos/farmacologia , Benzodiazepinas/química , Benzodiazepinas/farmacologia , Microscopia Crioeletrônica , Receptores de GABA-A/química , Regulação Alostérica/efeitos dos fármacos , Anestésicos Gerais/metabolismo , Barbitúricos/metabolismo , Benzodiazepinas/metabolismo , Bicuculina/química , Bicuculina/metabolismo , Bicuculina/farmacologia , Sítios de Ligação , Ligação Competitiva/efeitos dos fármacos , Diazepam/química , Diazepam/metabolismo , Diazepam/farmacologia , Eletrofisiologia , Etomidato/química , Etomidato/metabolismo , Etomidato/farmacologia , Flumazenil/farmacologia , Antagonistas de Receptores de GABA-A/química , Antagonistas de Receptores de GABA-A/metabolismo , Antagonistas de Receptores de GABA-A/farmacologia , Humanos , Ligantes , Modelos Moleculares , Conformação Molecular , Simulação de Dinâmica Molecular , Fenobarbital/química , Fenobarbital/metabolismo , Fenobarbital/farmacologia , Picrotoxina/química , Picrotoxina/metabolismo , Picrotoxina/farmacologia , Propofol/química , Propofol/metabolismo , Propofol/farmacologia , Receptores de GABA-A/metabolismo , Receptores de GABA-A/ultraestrutura , Ácido gama-Aminobutírico/química , Ácido gama-Aminobutírico/metabolismo , Ácido gama-Aminobutírico/farmacologia
3.
Pediatrics ; 146(2)2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32680879

RESUMO

OBJECTIVES: Cardiorespiratory and pulse oximetry monitoring in children who are hospitalized should balance benefits of detecting deterioration with potential harms of alarm fatigue. We developed recommendations for monitoring outside the ICU on the basis of available evidence and expert opinion. METHODS: We conducted a comprehensive literature search for studies addressing the utility of cardiorespiratory and pulse oximetry monitoring in common pediatric conditions and drafted candidate monitoring recommendations based on our findings. We convened a panel of nominees from national professional organizations with diverse expertise: nursing, medicine, respiratory therapy, biomedical engineering, and family advocacy. Using the RAND/University of California, Los Angeles Appropriateness Method, panelists rated recommendations for appropriateness and necessity in 3 sequential rating sessions and a moderated meeting. RESULTS: The panel evaluated 56 recommendations for intermittent and continuous monitoring for children hospitalized outside the ICU with 7 common conditions (eg, asthma, croup) and/or receiving common therapies (eg, supplemental oxygen, intravenous opioids). The panel reached agreement on the appropriateness of monitoring recommendations for 55 of 56 indications and on necessity of monitoring for 52. For mild or moderate asthma, croup, pneumonia, and bronchiolitis, the panel recommended intermittent vital sign or oximetry measurement only. The panel recommended continuous monitoring for severe disease in each respiratory condition as well as for a new or increased dose of intravenous opiate or benzodiazepine. CONCLUSIONS: Expert panel members agreed that intermittent vital sign assessment, rather than continuous monitoring, is appropriate management for a set of specific conditions of mild or moderate severity that require hospitalization.


Assuntos
Eletrocardiografia , Monitorização Fisiológica/métodos , Oximetria , Guias de Prática Clínica como Assunto , Transtornos Respiratórios/fisiopatologia , Testes de Função Respiratória , Analgésicos Opioides/efeitos adversos , Analgésicos Opioides/farmacologia , Benzodiazepinas/efeitos adversos , Benzodiazepinas/farmacologia , Criança , Criança Hospitalizada , Técnica Delfos , Relação Dose-Resposta a Droga , Humanos , Oxigenoterapia , Respiração/efeitos dos fármacos , Transtornos Respiratórios/etiologia , Sepse/fisiopatologia
4.
J Med Chem ; 63(13): 6941-6958, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32515951

RESUMO

It is urgent to find new antibiotic classes with activity against multidrug-resistant (MDR) Gram-negative pathogens as the pipeline of antibiotics is essentially empty. Modified pyrrolobenzodiazepines with a C8-linked aliphatic heterocycle provide a new class of broad-spectrum antibacterial agents with activity against MDR Gram-negative bacteria, including WHO priority pathogens. The structure-activity relationship established that the third ring was particularly important for Gram-negative activity. Minimum inhibitory concentrations for the lead compounds ranged from 0.125 to 2 mg/L for MDR Gram-negative, excluding Pseudomonas aeruginosa, and between 0.03 and 1 mg/L for MDR Gram-positive species. The lead compounds were rapidly bactericidal with >5 log reduction in viable count within 4 h for Acinetobacter baumannii and Klebsiella pneumoniae. The lead compound inhibited DNA gyrase in gel-based assays, with an IC50 of 3.16 ± 1.36 mg/L. This study provides a new chemical scaffold for developing novel broad-spectrum antibiotics which can help replenish the pipeline of antibiotics.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Benzodiazepinas/química , Benzodiazepinas/farmacologia , Desenho de Fármacos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Antibacterianos/metabolismo , Benzodiazepinas/metabolismo , Linhagem Celular , DNA Girase/química , DNA Girase/metabolismo , Bactérias Gram-Negativas/enzimologia , Humanos , Simulação de Acoplamento Molecular , Conformação Proteica
5.
Curr Opin Anaesthesiol ; 33(4): 506-511, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32530890

RESUMO

PURPOSE OF REVIEW: Anaesthesia and sedation are ubiquitous in contemporary medical practice. Developments in anaesthetic pharmacology are targeted on reducing physiological disturbance whilst maintaining or improving titrateability, recovery profile and patient experience. Remimazolam is a new short-acting benzodiazepine in the final stages of clinical development. RECENT FINDINGS: Clinical experience with remimazolam comprises volunteer studies and a limited number of clinical investigations. In addition, laboratory investigations explore the implications of its 'soft drug' pharmacology. SUMMARY: Remimazolam provides effective procedural sedation with superior success rates and recovery profile when compared to midazolam. Comparisons with propofol are required. Preliminary studies suggest potential for using remimazolam as the hypnotic component of general anaesthesia. Definitive studies are awaited. As a benzodiazepine, remimazolam could be evaluated as an anticonvulsant and for intensive care sedation.


Assuntos
Benzodiazepinas/farmacologia , Benzodiazepinas/uso terapêutico , Hipnóticos e Sedativos/farmacologia , Hipnóticos e Sedativos/uso terapêutico , Sedação Consciente , Humanos , Midazolam , Propofol
6.
Sleep Med Clin ; 15(2): 133-145, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32386689

RESUMO

The scope of this article is to review the effects on sleep of prescription drugs that are commonly prescribed for chronic insomnia in adults. The following groups are discussed: benzodiazepines and its receptor agonists, the dual orexin receptor antagonist suvorexant, melatonin and its receptor agonists, sedating antidepressants, and antipsychotics. Together with the neurobiologic and pharmacologic properties of these drugs, clinical effects are described, including subjective and objective effects on sleep duration, continuity, and architecture. Medical prescription information is given when available. Recently published American and European guidelines for the treatment of insomnia serve as reference frame.


Assuntos
Benzodiazepinas/uso terapêutico , Melatonina/uso terapêutico , Medicamentos Indutores do Sono/uso terapêutico , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Sono/efeitos dos fármacos , Antipsicóticos/farmacologia , Antipsicóticos/uso terapêutico , Azepinas/farmacologia , Azepinas/uso terapêutico , Benzodiazepinas/farmacologia , Humanos , Melatonina/farmacologia , Antagonistas dos Receptores de Orexina/farmacologia , Antagonistas dos Receptores de Orexina/uso terapêutico , Medicamentos sob Prescrição/farmacologia , Medicamentos sob Prescrição/uso terapêutico , Medicamentos Indutores do Sono/farmacologia , Triazóis/farmacologia , Triazóis/uso terapêutico
7.
Psychiatry Res ; 288: 112993, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32334277

RESUMO

Using prescription drugs during pregnancy is challenging and approached with caution. In this study, we present population-based information on prescription patterns of benzodiazepines and benzodiazepine-related drugs in the peripartum period. A population-based study of 1,154,817 pregnancies between 1997 and 2015 in Denmark, of which 205,406 (17.8%) pregnancies in women with a psychiatric history. Prescription drugs starting with Anatomical Therapeutic Chemical codes N05BA, N05CD, and N05CF from 12 months before pregnancy to 12 months following pregnancy were identified. We used generalised estimating equations to estimate the adjusted 5 year risk difference in the proportion of women redeeming benzodiazepines from 1 year to 5 years after. Logistic regression was used to analyze the association between characteristics and discontinuation of benzodiazepines during pregnancy. The prevalence of benzodiazepine prescriptions was 1.9% before pregnancy, 0.6% during pregnancy, and 1.3% after pregnancy. In women with a psychiatric history, the prevalence was 5-6 times higher. A significant decrease in prescriptions to women with a psychiatric history was observed, which was less profound among women with no psychiatric history. Approximately 90% of women discontinue benzodiazepines during pregnancy, with a higher percentage of women discontinuing from 1997 to 2015. The observed decrease is likely explained by changing treatment guidelines.


Assuntos
Benzodiazepinas/uso terapêutico , Prescrições de Medicamentos , Transtornos Mentais/tratamento farmacológico , Período Periparto/efeitos dos fármacos , Vigilância da População , Complicações na Gravidez/tratamento farmacológico , Adolescente , Adulto , Benzodiazepinas/farmacologia , Dinamarca/epidemiologia , Feminino , Humanos , Masculino , Transtornos Mentais/epidemiologia , Transtornos Mentais/psicologia , Pessoa de Meia-Idade , Período Periparto/psicologia , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/psicologia , Sistema de Registros , Estudos Retrospectivos , Adulto Jovem
8.
Life Sci ; 252: 117643, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32298738

RESUMO

AIMS: Non-peptide ligands of oxytocin receptor (OTR) have promising potentialities as therapeutic agents with improved pharmacological properties. WAY-267,464 is a non-peptide agonist which loses its agonist activity when its resorcinol moiety is methylated, yielding a partial antagonist (denoted here, WAY-Methylated). This study attempts to rationalize these opposing activities by comparative analyses of structural dynamicsof OTR in complex with these ligands. MAIN METHODS: Glide extra precision (XP) docking with and without positional constraints was employed to probe alternative binding poses of both WAY-267,464 and WAY-Methylated. The more preferred configuration of each system was subjected to an extended 2 µs MD simulation and the physics-based Molecular Mechanics-Generalized Born Surface Area (MM-GBSA) binding energy was used to rank the complexes with improved accuracy, in addition to empirical-based Glide docking score. Network analysis was performed, and the identified critical residues were cross-referenced with the experimental mutagenesis data. KEY FINDINGS: The added methyl groups in the antagonist WAY-Methylated enhanced hydrophobicity, resulting in a flipped binding pose deeper in the binding pocket. Interestingly, OTR responded to the methylation by stabilizing the initial inactive conformation, decreasing fluctuations and increasing the overall secondary structural composition. Conversely, the agonist WAY-267,464 produced larger fluctuations to allow the receptor to change from the default inactive state to a state of partial activation. These transitions were further supported by the identified critical residues overlapping with experimental mutagenesis data. SIGNIFICANCE: These findings provide insights into the activation mechanism of OTR by WAY-267.464 and its antagonism by WAY-Methylated.


Assuntos
Benzodiazepinas/farmacologia , Simulação de Dinâmica Molecular , Pirazóis/farmacologia , Receptores de Ocitocina/agonistas , Benzodiazepinas/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Metilação , Simulação de Acoplamento Molecular , Ligação Proteica , Pirazóis/química , Receptores de Ocitocina/antagonistas & inibidores , Receptores de Ocitocina/metabolismo
9.
Pediatr Blood Cancer ; 67(6): e28267, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32307821

RESUMO

BACKGROUND: The treatment of high-risk neuroblastoma continues to present a formidable challenge to pediatric oncology. Previous studies have shown that Bromodomain and extraterminal (BET) inhibitors can inhibit MYCN expression and suppress MYCN-amplified neuroblastoma in vivo. Furthermore, alterations within RAS-MAPK (mitogen-activated protein kinase) signaling play significant roles in neuroblastoma initiation, maintenance, and relapse, and mitogen-activated extracellular signal-regulated kinase (MEK) inhibitors demonstrate efficacy in subsets of neuroblastoma preclinical models. Finally, hyperactivation of RAS-MAPK signaling has been shown to promote resistance to BET inhibitors. Therefore, we examined the antitumor efficacy of combined BET/MEK inhibition utilizing I-BET726 or I-BET762 and trametinib in high-risk neuroblastoma. PROCEDURE: Utilizing a panel of genomically annotated neuroblastoma cell line models, we investigated the in vitro effects of combined BET/MEK inhibition on cell proliferation and apoptosis. Furthermore, we evaluated the effects of combined inhibition in neuroblastoma xenograft models. RESULTS: Combined BET and MEK inhibition demonstrated synergistic effects on the growth and survival of a large panel of neuroblastoma cell lines through augmentation of apoptosis. A combination therapy slowed tumor growth in a non-MYCN-amplified, NRAS-mutated neuroblastoma xenograft model, but had no efficacy in an MYCN-amplified model harboring a loss-of-function mutation in NF1. CONCLUSIONS: Combinatorial BET and MEK inhibition was synergistic in the vast majority of neuroblastoma cell lines in the in vitro setting but showed limited antitumor activity in vivo. Collectively, these data do not support clinical development of this combination in high-risk neuroblastoma.


Assuntos
Antineoplásicos/farmacologia , Benzodiazepinas/farmacologia , MAP Quinase Quinase 1/antagonistas & inibidores , Neuroblastoma/tratamento farmacológico , Proteínas/antagonistas & inibidores , Piridonas/farmacologia , Pirimidinonas/farmacologia , Animais , Apoptose , Proliferação de Células , Feminino , Humanos , Camundongos , Camundongos SCID , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
10.
J Exp Clin Cancer Res ; 39(1): 50, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32164732

RESUMO

BACKGROUND: Inhibition of ABC transporters is considered the most effective way to circumvent multidrug resistance (MDR). In the present study, we evaluated the MDR modulatory potential of ERK5-IN-1, a potent extracelluar signal regulated kinase 5 (ERK5) inhibitor. METHODS: The cytotoxicity and MDR reversal effect of ERK5-IN-1 were assessed by MTT assay. The KBv200-inoculated nude mice xenograft model was used for the in vivo study. Doxorubicin efflux and accumulation were measured by flow cytometry. The modulation of ABCB1 activity was measured by colorimetric ATPase assay and [125I]-iodoarylazidoprazosin (IAAP) photolabeling assay. Effect of ERK5-IN-1 on expression of ABCB1 and its downstream markers was measured by PCR and/or Western blot. Cell surface expression and subcellular localization of ABCB1 were tested by flow cytometry and immunofluorescence. RESULTS: Our results showed that ERK5-IN-1 significantly increased the sensitivity of vincristine, paclitaxel and doxorubicin in KBv200, MCF7/adr and HEK293/ABCB1 cells, respectively. This effect was not found in respective drug sensitive parental cell lines. Moreover, in vivo combination studies showed that ERK5-IN-1 effectively enhanced the antitumor activity of paclitaxel in KBv200 xenografts without causing addition toxicity. Mechanistically, ERK5-IN-1 increased intracellular accumulation of doxorubicin dose dependently by directly inhibiting the efflux function of ABCB1. ERK5-IN-1 stimulated the ABCB1 ATPase activity and inhibited the incorporation of [125I]-iodoarylazidoprazosin (IAAP) into ABCB1 in a concentration-dependent manner. In addition, ERK5-IN-1 treatment neither altered the expression level of ABCB1 nor blocked the phosphorylation of downstream Akt or Erk1/2. No significant reversal effect was observed on ABCG2-, ABCC1-, MRP7- and LRP-mediated drug resistance. CONCLUSIONS: Collectively, these results indicated that ERK5-IN-1 efficiently reversed ABCB1-mediated MDR by competitively inhibiting the ABCB1 drug efflux function. The use of ERK5-IN-1 to restore sensitivity to chemotherapy or to prevent resistance could be a potential treatment strategy for cancer patients.


Assuntos
Benzodiazepinas/administração & dosagem , Doxorrubicina/administração & dosagem , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Inibidores de Proteínas Quinases/administração & dosagem , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Benzodiazepinas/química , Benzodiazepinas/farmacologia , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Células HEK293 , Células HL-60 , Humanos , Camundongos , Camundongos Nus , Proteína Quinase 7 Ativada por Mitógeno/antagonistas & inibidores , Neoplasias , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Sci Rep ; 10(1): 2148, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32041972

RESUMO

Down syndrome (DS) is frequently comorbid with congenital heart disease and has recently been shown to reduce the sedative effect of benzodiazepine (BDZ)-class anesthesia but this effect in a clinical setting has not been studied. Therefore, this study compared midazolam sedation after heart surgery in DS and normal children. We retrospectively reviewed patient records in our pediatric intensive care unit (PICU) of pediatric cardiovascular operations between March 2015 and March 2018. We selected five days of continuous post-operative data just after termination of muscle relaxants. Midazolam sedation was estimated by Bayesian inference for generalized linear mixed models. We enrolled 104 patients (average age 26 weeks) of which 16 (15%) had DS. DS patients had a high probability of receiving a higher midazolam dosage and dexmedetomidine dosage over the study period (probability = 0.99, probability = 0.97) while depth of sedation was not different in DS patients (probability = 0.35). Multi regression modeling included severity scores and demographic data showed DS decreases midazolam sedation compared with controls (posterior OR = 1.32, 95% CrI = 1.01-1.75). In conclusion, midazolam dosages should be carefully adjusted as DS significantly decreases midazolam sedative effect in pediatric heart surgery patients.


Assuntos
Síndrome de Down/metabolismo , Cardiopatias Congênitas/metabolismo , Midazolam/farmacologia , Teorema de Bayes , Benzodiazepinas/farmacologia , Sistema Cardiovascular , Sedação Profunda/métodos , Síndrome de Down/fisiopatologia , Feminino , Cardiopatias Congênitas/cirurgia , Humanos , Hipnóticos e Sedativos/farmacologia , Lactente , Recém-Nascido , Unidades de Terapia Intensiva Pediátrica , Tempo de Internação , Masculino , Midazolam/administração & dosagem , Respiração Artificial , Estudos Retrospectivos
12.
Rev Med Suisse ; 16(681): 314-317, 2020 Feb 12.
Artigo em Francês | MEDLINE | ID: mdl-32049453

RESUMO

Suicide is a common cause of death in Switzerland. It often occurs during a period of crisis marked by a disruption of the subject's intrapsychic, interpersonal or social balance. The management of this crisis is crucial and essentially psychotherapeutic. Drug therapy may be necessary for the management of acute symptoms or for the prevention of long-term suicidal risk. Benzodiazepines and atypical antipsychotics are often used for acute symptoms such as anxiety or sleep disorders while other molecules are recognized in reducing long-term suicidal risk. Some disorders, such as borderline personality disorder, account for more frequent suicidal behaviors. The pharmacological management of these specific situations is discussed.


Assuntos
Antipsicóticos/farmacologia , Suicídio/prevenção & controle , Suicídio/psicologia , Benzodiazepinas/farmacologia , Transtorno da Personalidade Borderline/psicologia , Humanos , Fatores de Risco , Ideação Suicida , Suíça
13.
J Neurosci ; 40(11): 2282-2295, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32024781

RESUMO

Oxytocin (OT) is critical for the expression of social behavior across a wide array of species; however, the role of this system in the encoding of socially relevant information is not well understood. In the present study, we show that chemogenetic activation of OT neurons within the paraventricular nucleus of the hypothalamus (PVH) of male mice (OT-Ires-Cre) enhanced social investigation during a social choice test, while chemogenetic inhibition of these neurons abolished typical social preferences. These data suggest that activation of the OT system is necessary to direct behavior preferentially toward social stimuli. To determine whether the presence of a social stimulus is sufficient to induce activation of PVH-OT neurons, we performed the first definitive recording of OT neurons in awake mice using two-photon calcium imaging. These recordings demonstrate that social stimuli activate PVH-OT neurons and that these neurons differentially encode social and nonsocial stimuli, suggesting that PVH-OT neurons may act to convey social salience of environmental stimuli. Finally, an attenuation of social salience is associated with social disorders, such as autism. We therefore also examined possible OT system dysfunction in a mouse model of autism, Shank3b knock-out (KO) mice. Male Shank3b KO mice showed a marked reduction in PVH-OT neuron number and administration of an OT receptor agonist improved social deficits. Overall, these data suggest that the presence of a social stimulus induces activation of the PVH-OT neurons to promote adaptive social behavior responses.SIGNIFICANCE STATEMENT Although the oxytocin (OT) system is well known to regulate a diverse array of social behaviors, the mechanism in which OT acts to promote the appropriate social response is poorly understood. One hypothesis is that the presence of social conspecifics activates the OT system to generate an adaptive social response. Here, we selectively recorded from OT neurons in the paraventricular hypothalamic nucleus (PVH) to show that social stimulus exposure indeed induces activation of the OT system. We also show that activation of the OT system is necessary to promote social behavior and that mice with abnormal social behavior have reduced numbers of PVH-OT neurons. Finally, aberrant social behavior in these mice was rescued by administration of an OT receptor agonist.


Assuntos
Neurônios/fisiologia , Ocitocina/fisiologia , Núcleo Hipotalâmico Paraventricular/fisiologia , Comportamento Social , Potenciais de Ação/efeitos dos fármacos , Animais , Comportamento Apetitivo/efeitos dos fármacos , Comportamento Apetitivo/fisiologia , Transtorno Autístico/fisiopatologia , Benzodiazepinas/farmacologia , Sinalização do Cálcio , Clozapina/farmacologia , Modelos Animais de Doenças , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Genes Reporter , Masculino , Camundongos , Camundongos Knockout , Neurônios/efeitos dos fármacos , Ocitocina/análise , Núcleo Hipotalâmico Paraventricular/fisiopatologia , Técnicas de Patch-Clamp , Pirazóis/farmacologia , Receptores de Ocitocina/agonistas , Receptores de Ocitocina/antagonistas & inibidores , Receptores de Ocitocina/fisiologia , Vigília
14.
Phytother Res ; 34(6): 1436-1445, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31985131

RESUMO

Stress is an increasing problem that can result in various psychiatric and somatoform symptoms. Among others, benzodiazepines and valerian preparations are used to treat stress symptoms. The aim of this study was to investigate whether the prescription of a fixed herbal extract combination of valerian, lemon balm, passionflower, and butterbur (Ze 185) changes the prescription pattern of benzodiazepines in hospitalized psychiatric patients. In a retrospective case-control study, anonymized medical record data from 3,252 psychiatric in-house patients were analysed over a 3.5-year period. Cases (n = 1,548) with a prescription of Ze 185 and controls (n = 1,704) were matched by age, gender, hospitalization interval, and main International Classification of Diseases, Version 10 F-diagnoses. The primary objective was to investigate the effect of Ze 185 on the prescription pattern of benzodiazepines. Secondary objectives investigated the prescriptions of concomitant drugs and effectiveness of the hospital stay. Distribution of drug classes was analysed using the WHO's anatomic-therapeutic-chemical code. Data showed that both treatment modalities had a comparable clinical effectiveness but with significantly less prescriptions of benzodiazepines in the Ze 185 group (p = .006). This is of clinical importance because suitable alternatives to benzodiazepines are desirable. To obtain more support for this hypothesis, a dedicated randomized, controlled clinical trial monitoring drug safety is required.


Assuntos
Benzodiazepinas/uso terapêutico , Hipnóticos e Sedativos/uso terapêutico , Melissa/química , Passiflora/química , Petasites/química , Extratos Vegetais/uso terapêutico , Valeriana/química , Benzodiazepinas/farmacologia , Estudos de Casos e Controles , Feminino , Humanos , Hipnóticos e Sedativos/farmacologia , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/farmacologia , Estudos Retrospectivos
15.
J Am Chem Soc ; 142(7): 3440-3448, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-31944685

RESUMO

Antitumor pyrrolobenzodiazepines (PBDs), lincosamide antibiotics, quorum-sensing molecule hormaomycin, and antimicrobial griselimycin are structurally and functionally diverse groups of actinobacterial metabolites. The common feature of these compounds is the incorporation of l-tyrosine- or l-leucine-derived 4-alkyl-l-proline derivatives (APDs) in their structures. Here, we report that the last reaction in the biosynthetic pathway of APDs, catalyzed by F420H2-dependent Apd6 reductases, contributes to the structural diversity of APD precursors. Specifically, the heterologous overproduction of six Apd6 enzymes demonstrated that Apd6 from the biosynthesis of PBDs and hormaomycin can reduce only an endocyclic imine double bond, whereas Apd6 LmbY and partially GriH from the biosyntheses of lincomycin and griselimycin, respectively, also reduce the more inert exocyclic double bond of the same 4-substituted Δ1-pyrroline-2-carboxylic acid substrate, making LmbY and GriH unusual, if not unique, among reductases. Furthermore, the differences in the reaction specificity of the Apd6 reductases determine the formation of the fully saturated APD moiety of lincomycin versus the unsaturated APD moiety of PBDs, providing molecules with optimal shapes to bind their distinct biological targets. Moreover, the Apd6 reductases establish the first F420H2-dependent enzymes from the luciferase-like hydride transferase protein superfamily in the biosynthesis of bioactive molecules. Finally, our bioinformatics analysis demonstrates that Apd6 and their homologues, widely distributed within several bacterial phyla, play a role in the formation of novel yet unknown natural products with incorporated l-proline-like precursors and likely in the microbial central metabolism.


Assuntos
Benzodiazepinas/metabolismo , Lincomicina/biossíntese , Oxirredutases/metabolismo , Pirróis/metabolismo , Benzodiazepinas/química , Benzodiazepinas/farmacologia , Catálise , Depsipeptídeos/biossíntese , Depsipeptídeos/química , Depsipeptídeos/farmacologia , Lincomicina/química , Lincomicina/farmacologia , Modelos Moleculares , Oxirredutases/química , Peptídeos Cíclicos/biossíntese , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Prolina/análogos & derivados , Prolina/metabolismo , Pirróis/química , Pirróis/farmacologia , Riboflavina/análogos & derivados , Riboflavina/química , Riboflavina/metabolismo , Especificidade por Substrato , Tirosina/análogos & derivados , Tirosina/metabolismo
16.
Int J Mol Sci ; 21(1)2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31947863

RESUMO

Many allosteric binding sites that modulate gamma aminobutyric acid (GABA) effects have been described in heteropentameric GABA type A (GABAA) receptors, among them sites for benzodiazepines, pyrazoloquinolinones and etomidate. Diazepam not only binds at the high affinity extracellular "canonical" site, but also at sites in the transmembrane domain. Many ligands of the benzodiazepine binding site interact also with homologous sites in the extracellular domain, among them the pyrazoloquinolinones that exert modulation at extracellular α+/ß- sites. Additional interaction of this chemotype with the sites for etomidate has also been described. We have recently described a new indole-based scaffold with pharmacophore features highly similar to pyrazoloquinolinones as a novel class of GABAA receptor modulators. Contrary to what the pharmacophore overlap suggests, the ligand presented here behaves very differently from the identically substituted pyrazoloquinolinone. Structural evidence demonstrates that small changes in pharmacophore features can induce radical changes in ligand binding properties. Analysis of published data reveals that many chemotypes display a strong tendency to interact promiscuously with binding sites in the transmembrane domain and others in the extracellular domain of the same receptor. Further structural investigations of this phenomenon should enable a more targeted path to less promiscuous ligands, potentially reducing side effect liabilities.


Assuntos
Antagonistas de Receptores de GABA-A/química , Antagonistas de Receptores de GABA-A/farmacologia , Domínios Proteicos/efeitos dos fármacos , Receptores de GABA-A/metabolismo , Regulação Alostérica/efeitos dos fármacos , Animais , Benzodiazepinas/química , Benzodiazepinas/farmacologia , Sítios de Ligação/efeitos dos fármacos , Desenho de Fármacos , Humanos , Ligantes , Modelos Moleculares , Quinolonas/química , Quinolonas/farmacologia , Receptores de GABA-A/química , Ácido gama-Aminobutírico/metabolismo
17.
Biochimie ; 168: 297-306, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31770565

RESUMO

The main function of AChE is the hydrolysis of the neurotransmitter acetylcholine (ACh) at the neuromuscular and in cholinergic brain synapses. In some pathologies, loss of cholinergic neurons may be associated with a deficiency of ACh in specific brain areas. Consequently, the study of new safe drugs that inhibit AChE is important, because they can increase ACh levels in the synaptic cleft without adverse effects. Here, we evaluated the effects of JM-20 (a benzodiazepine-dihydropyridine hybrid molecule) on cholinesterase (ChE) activities from distinct sources (AChE from Electrophorus electricus (EeAChE), human erythrocyte membranes (HsAChE (ghost)), total erythrocyte (HsAChE (erythrocyte)) and BChE from plasma (HsBChE) and purified enzyme from the horse (EcBChE)). Kinetic parameters were determined in the presence of 0.05-1.6 mM of substrate concentration. The interactions ChEs with JM-20 were performed using molecular docking simulations. JM-20 inhibited all tested AChE but not BChE. The IC50 values were 123 nM ± 0.2 (EeAChE), 158 nM ± 0.1 (ghost HsAChE), and 172 nM ± 0.2 (erythrocytic HsAChE). JM-20 caused a mixed type of inhibition (it altered Km and Vmax of AChE). The molecular docking indicated the binding poses and the most plausible active isomer of JM-20. Besides giving important data for future drug design, our results help us understand the mode of action of JM-20 as a specific inhibitor of AChE enzymes.


Assuntos
Acetilcolinesterase/metabolismo , Benzodiazepinas/farmacologia , Inibidores da Colinesterase/farmacologia , Niacina/análogos & derivados , Animais , Desenho de Fármacos , Electrophorus , Cavalos , Humanos , Cinética , Niacina/farmacologia
18.
Gastroenterology ; 158(3): 625-637.e13, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31622625

RESUMO

BACKGROUND & AIMS: Gamma chain (γc) cytokines (interleukin [IL]2, IL4, IL7, IL9, IL15, and IL21) signal via a common γc receptor. IL2 regulates the immune response, whereas IL21 and IL15 contribute to development of autoimmune disorders, including celiac disease. We investigated whether BNZ-2, a peptide designed to inhibit IL15 and IL21, blocks these cytokines selectively and its effects on intraepithelial cytotoxic T cells. METHODS: We obtained duodenal biopsies from 9 patients with potential celiac disease (positive results from tests for anti-TG2 but no villous atrophy), 30 patients with untreated celiac disease (with villous atrophy), and 5 patients with treated celiac disease (on a gluten-free diet), as well as 43 individuals without celiac disease (controls). We stimulated primary intestinal intraepithelial CD8+ T-cell lines, or CD8+ T cells directly isolated from intestinal biopsies, with γc cytokines in presence or absence of BNZ-2. Cells were analyzed by immunoblots, flow cytometry, or RNA-sequencing analysis for phosphorylation of signaling molecules, gene expression profiles, proliferation, and levels of granzyme B. RESULTS: Duodenal tissues from patients with untreated celiac disease had increased levels of messenger RNAs encoding IL15 receptor subunit alpha (IL15RA) and IL21 compared with tissues from patients with potential celiac disease and controls. Activation of intraepithelial cytotoxic T cells with IL15 or IL21 induced separate signaling pathways; incubation of the cells with IL15 and IL21 cooperatively increased their transcriptional activity, proliferation, and cytolytic properties. BNZ-2 specifically inhibited the effects of IL15 and IL21, but not of other γc cytokines. CONCLUSIONS: We found increased expression of IL15RA and IL21 in duodenal tissues from patients with untreated celiac disease compared with controls. IL15 and IL21 cooperatively activated intestinal intraepithelial cytotoxic T cells. In particular, they increased their transcriptional activity, proliferation, and cytolytic activity. The peptide BNZ-2 blocked these effects, but not those of other γc cytokines, including IL2. BNZ-2 might be used to prevent cytotoxic T-cell-mediated tissue damage in complex immune disorders exhibiting upregulation of IL15 and IL21.


Assuntos
Benzodiazepinas/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/fisiologia , Subunidade gama Comum de Receptores de Interleucina/antagonistas & inibidores , Interleucina-15/farmacologia , Interleucinas/farmacologia , Estudos de Casos e Controles , Doença Celíaca/imunologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Reprogramação Celular/efeitos dos fármacos , Duodeno/patologia , Humanos , Interleucina-15/genética , Interleucinas/genética , Cultura Primária de Células , RNA Mensageiro , Receptores de Interleucina-15/genética , Transdução de Sinais/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos
19.
Anesth Analg ; 130(4): 1077-1084, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31490256

RESUMO

BACKGROUND: Neuromodulation, as a therapeutic modality for pain treatment, is an alternative to opioid therapies and therefore receiving increased interest and use. Neuromodulation at a peripheral nerve target, in the form of bilateral electrical pudendal nerve stimulation (bPNS), has been shown to reduce bladder hypersensitivity in rats and anecdotally reduces pain in humans with pelvic pain of urological origin. Recent studies have identified a role for spinal γ-aminobutyric acid (GABA) receptors in this effect. Concomitant medication use, such as benzodiazepines, could alter responses to neuromodulation, and so before the development of a clinical trial to confirm translation of this potential therapy, the potential interactions between acute and chronic use of benzodiazepines and bPNS were examined in a preclinical model. METHODS: Bladder hypersensitivity was produced by neonatal bladder inflammation in rat pups coupled with a second inflammatory insult as an adult. Diazepam (1-5 mg/kg intraperitoneal [i.p.]) or vehicle was administered acutely (with or without bPNS) and chronically (5 mg/kg subcutaneous [s.c.] daily for 2 weeks before the final experiment). bPNS was delivered as bilateral biphasic electrical stimulation of the mixed motor/sensory component of the pudendal nerves. Visceromotor responses (VMRs; abdominal muscle contractile responses to urinary bladder distension [UBD]) were used as nociceptive end points. Due to the profound effects of diazepam, the effect of midazolam (0.5-1.0 mg/kg i.p.) on VMRs and bPNS effects was also studied. RESULTS: Diazepam and midazolam both produced a dose-dependent, flumazenil-reversible inhibition of VMRs to UBD. bPNS resulted in statistically significant inhibition of VMRs to UBD in hypersensitive rats that had received vehicle injections. Select doses of diazepam and midazolam suppressed the inhibitory effect of bPNS on VMRs. CONCLUSIONS: This study suggests that inhibitory effects of bPNS on bladder pain could be suppressed in subjects receiving benzodiazepine therapy, suggesting that potential clinical testing of pudendal nerve stimulation for the treatment of painful bladder syndromes may be confounded by the use of benzodiazepines. Clinical assessment of other forms of neuromodulation should also be screened for impacts of benzodiazepines.


Assuntos
Benzodiazepinas/farmacologia , Nociceptividade/efeitos dos fármacos , Nervo Pudendo/efeitos dos fármacos , Bexiga Urinária/efeitos dos fármacos , Animais , Diazepam/farmacologia , Relação Dose-Resposta a Droga , Estimulação Elétrica , Feminino , Flumazenil/farmacologia , Moduladores GABAérgicos/farmacologia , Midazolam/farmacologia , Neurônios Motores/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Células Receptoras Sensoriais/efeitos dos fármacos
20.
Life Sci ; 239: 117033, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31697950

RESUMO

AIMS: Benzodiazepines (BZDs) produce various pharmacological actions by binding to and allosterically regulating GABAA receptors. Several in vitro studies have demonstrated diazepam, the prototypic BZD, produces a high-dose action that cannot be countered with the classical BZD-binding site antagonist flumazenil. Here, we investigate the existence and behavioral relevance of non-classical BZD binding sites in zebrafish larvae. MAIN METHODS: Zebrafish larvae were treated with a series of BZDs alone or combined with flumazenil, bicuculline (a non-selective GABAA receptor antagonist), or RO 15-4513 (a general BZD antagonist and a proposed antagonist interacting with α+/ß- interfaces in α4/6/ß3δ receptors), and their locomotor activities and behavioral phenotypes were recorded. KEY FINDINGS: Diazepam-induced hypolocomotion (sedation-like state) at low doses (10 and 20 mg L-1) was effectively antagonized by flumazenil or bicuculline, while diazepam-induced immobility (anesthesia-like state) at higher dose (30 mg L-1) was prevented by bicuculline (3 mg L-1) but not flumazenil, even at doses up to 150 mg L-1. Ro 15-4513 also failed to efficiently antagonize diazepam-induced immobility. Immobility induced by high dose of another 1,4-BZD, clonazepam, was also resistant to flumazenil. SIGNIFICANCE: These results provide direct in vivo evidence for non-classical BZD-binding sites, which may be located at the second transmembrane domain of GABAA receptors and contribute to BZD-induced anesthesia.


Assuntos
Benzodiazepinas/metabolismo , Benzodiazepinas/farmacologia , Flumazenil/farmacologia , Moduladores GABAérgicos/farmacologia , Atividade Motora/efeitos dos fármacos , Receptores de GABA-A/efeitos dos fármacos , Animais , Azidas/farmacologia , Benzodiazepinas/toxicidade , Bicuculina/farmacologia , Sítios de Ligação/efeitos dos fármacos , Clonazepam/farmacologia , Relação Dose-Resposta a Droga , Feminino , Flumazenil/toxicidade , Antagonistas GABAérgicos/farmacologia , Moduladores GABAérgicos/toxicidade , Larva , Masculino , Peixe-Zebra
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