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1.
Cell ; 167(3): 587, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27768878

RESUMO

Since the 1970s, racetams have been in use as cognitive enhancers. Levetiracetam was discovered to have antiseizure activity in animal models and was then found to bind to SV2A in synaptic and endocrine vesicles. Brivaracetam, an analog of levetiracetam, was identified in a medicinal chemistry campaign with the objective of discovering analogs with higher affinity at racetam-binding sites and greater antiseizure potency.


Assuntos
Anticonvulsivantes/química , Epilepsias Parciais/tratamento farmacológico , Epilepsia Generalizada/tratamento farmacológico , Glicoproteínas de Membrana/química , Proteínas do Tecido Nervoso/química , Pirrolidinonas/química , Animais , Anticonvulsivantes/metabolismo , Anticonvulsivantes/uso terapêutico , Sítios de Ligação , Humanos , Levetiracetam , Ligantes , Piracetam/análogos & derivados , Piracetam/química , Piracetam/uso terapêutico , Ligação Proteica , Conformação Proteica , Pirrolidinonas/uso terapêutico
2.
Nucleic Acids Res ; 52(5): 2546-2564, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38214235

RESUMO

Thiolutin is a natural product transcription inhibitor with an unresolved mode of action. Thiolutin and the related dithiolopyrrolone holomycin chelate Zn2+ and previous studies have concluded that RNA Polymerase II (Pol II) inhibition in vivo is indirect. Here, we present chemicogenetic and biochemical approaches to investigate thiolutin's mode of action in Saccharomyces cerevisiae. We identify mutants that alter sensitivity to thiolutin. We provide genetic evidence that thiolutin causes oxidation of thioredoxins in vivo and that thiolutin both induces oxidative stress and interacts functionally with multiple metals including Mn2+ and Cu2+, and not just Zn2+. Finally, we show direct inhibition of RNA polymerase II (Pol II) transcription initiation by thiolutin in vitro in support of classical studies that thiolutin can directly inhibit transcription in vitro. Inhibition requires both Mn2+ and appropriate reduction of thiolutin as excess DTT abrogates its effects. Pause prone, defective elongation can be observed in vitro if inhibition is bypassed. Thiolutin effects on Pol II occupancy in vivo are widespread but major effects are consistent with prior observations for Tor pathway inhibition and stress induction, suggesting that thiolutin use in vivo should be restricted to studies on its modes of action and not as an experimental tool.


Assuntos
Pirrolidinonas , RNA Polimerase II , Proteínas de Saccharomyces cerevisiae , Pirrolidinonas/farmacologia , RNA Polimerase II/antagonistas & inibidores , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/genética , Transcrição Gênica , Zinco
3.
Proc Natl Acad Sci U S A ; 120(48): e2313197120, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37988466

RESUMO

A lead aryl pyrrolidinone anilide identified using high-throughput in vivo screening was optimized for efficacy, crop safety, and weed spectrum, resulting in tetflupyrolimet. Known modes of action were ruled out through in vitro enzyme and in vivo plant-based assays. Genomic sequencing of aryl pyrrolidinone anilide-resistant Arabidopsis thaliana progeny combined with nutrient reversal experiments and metabolomic analyses confirmed that the molecular target of the chemistry was dihydroorotate dehydrogenase (DHODH), the enzyme that catalyzes the fourth step in the de novo pyrimidine biosynthesis pathway. In vitro enzymatic and biophysical assays and a cocrystal structure with purified recombinant plant DHODH further confirmed this enzyme as the target site of this class of chemistry. Like known inhibitors of other DHODH orthologs, these molecules occupy the membrane-adjacent binding site of the electron acceptor ubiquinone. Identification of a new herbicidal chemical scaffold paired with a novel mode of action, the first such finding in over three decades, represents an important leap in combatting weed resistance and feeding a growing worldwide population.


Assuntos
Herbicidas , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Di-Hidro-Orotato Desidrogenase , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Herbicidas/farmacologia , Pirimidinas/farmacologia , Anilidas , Pirrolidinonas , Inibidores Enzimáticos/farmacologia
4.
Ann Neurol ; 93(5): 911-921, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36585914

RESUMO

OBJECTIVE: The purpose of this study was to explore longitudinal changes in synaptic density after ischemic stroke in vivo with synaptic vesicle protein 2A (SV2A) positron emission tomography (PET). METHODS: We recruited patients with an ischemic stroke to undergo 11 C-UCB-J PET/MR within the first month and 6 months after the stroke. We investigated longitudinal changes of partial volume corrected 11 C-UCB-J standardized uptake value ratio (SUVR; relative to centrum semiovale) within the ischemic lesion, peri-ischemic area and unaffected ipsilesional and contralesional grey matter. We also explored crossed cerebellar diaschisis at 6 months. Additionally, we defined brain regions potentially influencing upper limb motor recovery after stroke and studied 11 C-UCB-J SUVR evolution in comparison to baseline. RESULTS: In 13 patients (age = 67 ± 15 years) we observed decreasing 11 C-UCB-J SUVR in the ischemic lesion (ΔSUVR = -1.0, p = 0.001) and peri-ischemic area (ΔSUVR = -0.31, p = 0.02) at 6 months after stroke compared to baseline. Crossed cerebellar diaschisis as measured with 11 C-UCB-J SUVR was present in 11 of 13 (85%) patients at 6 months. The 11 C-UCB-J SUVR did not augment in ipsilesional or contralesional brain regions associated with motor recovery. On the contrary, there was an overall trend of declining 11 C-UCB-J SUVR in these brain regions, reaching statistical significance only in the nonlesioned part of the ipsilesional supplementary motor area (ΔSUVR = -0.83, p = 0.046). INTERPRETATION: At 6 months after stroke, synaptic density further declined in the ischemic lesion and peri-ischemic area compared to baseline. Brain regions previously demonstrated to be associated with motor recovery after stroke did not show increases in synaptic density. ANN NEUROL 2023;93:911-921.


Assuntos
Diásquise , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Pirrolidinonas/metabolismo , Glicoproteínas de Membrana/metabolismo , Piridinas/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/metabolismo
5.
Epilepsia ; 65(2): 456-472, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38052481

RESUMO

OBJECTIVE: There are few comparative data on the third-generation antiseizure medications (ASMs). We aimed to assess and compare the effectiveness of brivaracetam (BRV), eslicarbazepine acetate (ESL), lacosamide (LCM), and perampanel (PER) in people with epilepsy (PWE). Efficacy and tolerability were compared as secondary objectives. METHODS: This multicenter, retrospective study collected data from 22 Italian neurology/epilepsy centers. All adult PWE who started add-on treatment with one of the studied ASMs between January 2018 and October 2021 were included. Retention rate was established as effectiveness measure and described using Kaplan-Meier curves and the best fitting survival model. The responder status and the occurrence of adverse events (AEs) were used to evaluate efficacy and safety, respectively. The odds of AEs and drug efficacy were estimated by two multilevel logistic models. RESULTS: A total of 960 patients (52.92% females, median age = 43 years) met the inclusion criteria. They mainly suffered from structural epilepsy (52.29%) with monthly (46.2%) focal seizures (69.58%). Compared with LCM, all the studied ASMs had a higher dropout risk, statistically significant in the BRV levetiracetam (LEV)-naïve (hazard ratio [HR] = 1.97, 95% confidence interval [CI] = 1.17-3.29) and PER groups (HR = 1.64, 95% CI = 1.06-2.55). Women were at higher risk of discontinuing ESL (HR = 5.33, 95% CI = 1.71-16.61), as well as PER-treated patients with unknown epilepsy etiology versus those with structural etiology (HR = 1.74, 95% CI = 1.05-2.88). BRV with prior LEV therapy showed lower odds of efficacy (odds ratio [OR] = .08, 95% CI = .01-.48) versus LCM, whereas a higher efficacy was observed in women treated with BRV and LEV-naïve (OR = 10.32, 95% CI = 1.55-68.78) versus men. PER (OR = 6.93, 95% CI = 3.32-14.44) and BRV in LEV-naïve patients (OR = 6.80, 95% CI = 2.64-17.52) had a higher chance of AEs than LCM. SIGNIFICANCE: Comparative evidence from real-world studies may help clinicians to tailor treatments according to patients' demographic and clinical characteristics.


Assuntos
Epilepsias Parciais , Epilepsia , Nitrilas , Piridonas , Masculino , Adulto , Humanos , Feminino , Anticonvulsivantes/efeitos adversos , Epilepsias Parciais/tratamento farmacológico , Estudos Retrospectivos , Levetiracetam/uso terapêutico , Lacosamida/uso terapêutico , Epilepsia/tratamento farmacológico , Pirrolidinonas/uso terapêutico , Resultado do Tratamento
6.
Epilepsia ; 65(3): 620-629, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38158709

RESUMO

OBJECTIVE: The aim of this study was to determine whether clinical efficacy and reported adverse effects (AEs) of the newer antiseizure medications (ASMs) brivaracetam (BRV), lacosamide (LCM), and perampanel (PER) have been associated with plasma levels of these ASMs. We also investigated whether plasma levels outside the reference range has led to dose adjustments. METHODS: Plasma levels of 300 people with epilepsy (PWE) seen at our tertiary epilepsy center were determined by liquid chromatography-tandem mass spectrometry. PWE received BRV (n = 100), LCM (n = 100), or PER (n = 100), in most cases in polytherapy. Demographic and clinical data were retrospectively analyzed and related to plasma levels. Clinical efficacy of BRV, LCM, or PER was assessed retrospectively by comparing seizure frequency at the time of current blood draw with seizure frequency at the time of first administration. AEs were also recorded and, if reported, compared retrospectively with the time of first administration. RESULTS: No significant associations were found between plasma levels of BRV, LCM, or PER and seizure freedom (BRV, p = 1.000; LCM, p = .243; PER, p = .113) or responder status (BRV, p = .118; LCM, p = .478; PER, p = .069) at presentation. There was also no pattern between plasma levels and the occurrence of AEs. In the majority of cases, drug levels outside the reference ranges have not led to adjustments in the daily doses of BRV (93.5%), LCM (93.9%), or PER (89.1%). SIGNIFICANCE: Plasma levels at a given time point did not allow conclusions to be drawn about seizure control or the occurrence of AEs. Our findings indicate that efficacy and tolerability cannot be predicted based on averaged data from a single plasma measurement due to high interindividual variability. Instead, individual reference values should be established when sufficient clinical data are available, in line with the 2008 International League Against Epilepsy position paper on therapeutic drug monitoring.


Assuntos
Anticonvulsivantes , Epilepsia , Nitrilas , Piridonas , Humanos , Lacosamida/uso terapêutico , Anticonvulsivantes/efeitos adversos , Estudos Retrospectivos , Epilepsia/tratamento farmacológico , Epilepsia/induzido quimicamente , Pirrolidinonas/efeitos adversos , Convulsões/tratamento farmacológico , Convulsões/induzido quimicamente , Resultado do Tratamento , Quimioterapia Combinada
7.
Microb Cell Fact ; 23(1): 87, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515152

RESUMO

BACKGROUND: Natural tetramates are a family of hybrid polyketides bearing tetramic acid (pyrrolidine-2,4-dione) moiety exhibiting a broad range of bioactivities. Biosynthesis of tetramates in microorganisms is normally directed by hybrid polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) machineries, which form the tetramic acid ring by recruiting trans- or cis-acting thioesterase-like Dieckmann cyclase in bacteria. There are a group of tetramates with unique skeleton of 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione, which remain to be investigated for their biosynthetic logics. RESULTS: Herein, the tetramate type compounds bripiodionen (BPD) and its new analog, featuring the rare skeleton of 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione, were discovered from the sponge symbiotic bacterial Streptomyces reniochalinae LHW50302. Gene deletion and mutant complementation revealed the production of BPDs being correlated with a PKS-NRPS biosynthetic gene cluster (BGC), in which a Dieckmann cyclase gene bpdE was identified by sit-directed mutations. According to bioinformatic analysis, the tetramic acid moiety of BPDs should be formed on an atypical NRPS module constituted by two discrete proteins, including the C (condensation)-A (adenylation)-T (thiolation) domains of BpdC and the A-T domains of BpdD. Further site-directed mutagenetic analysis confirmed the natural silence of the A domain in BpdC and the functional necessities of the two T domains, therefore suggesting that an unusual aminoacyl transthiolation should occur between the T domains of two NRPS subunits. Additionally, characterization of a LuxR type regulator gene led to seven- to eight-fold increasement of BPDs production. The study presents the first biosynthesis case of the natural molecule with 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione skeleton. Genomic mining using BpdD as probe reveals that the aminoacyl transthiolation between separate NRPS subunits should occur in a certain population of NRPSs in nature.


Assuntos
Vias Biossintéticas , Policetídeo Sintases , Pirrolidinonas , Policetídeo Sintases/metabolismo , Bactérias/metabolismo , Piranos/metabolismo , Esqueleto/metabolismo , Peptídeo Sintases/genética
8.
Rapid Commun Mass Spectrom ; 38(2): e9651, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38124167

RESUMO

RATIONALE: Pyrrolidone-based drugs find widespread use in treating conditions such as epilepsy and Alzheimer's disease, and in various other medical applications. Brivaracetam, the latest generation of pyrrolidone drugs, has exhibited significant promise owing to chemical structure modifications. Its affinity to the SV2A receptor is double that of the previous-generation drug, levetiracetam. Consequently, brivaracetam holds substantial potential for diverse applications. As a novel drug not yet included in the pharmacopeias of developed nations, comprehensive analysis and research are necessary to guarantee its safe utilization in clinical settings. METHODS: A liquid chromatography quadrupole time-of-flight tandem mass spectrometry (LC/QTOFMS) method has been developed to effectively separate, identify and characterize both the degradation products and process-related substances of brivaracetam. Stress testing of the sample was carried out following the guidelines outlined in ICH Q1A(R2). The structures of these impurities were identified through positive electrospray ionization QTOF high-resolution MS and NMR spectroscopy. Additionally, the formation mechanism of each degradation product is thoroughly discussed. RESULTS: Under the analytical conditions outlined in this paper, brivaracetam and its degradation products were effectively separated. Thirteen degradation products were detected and characterized, shedding light on their origins and degradation pathways. Among these, three degradation products align with previously reported impurities, and two unreported degradation products were synthesized and confirmed through NMR spectroscopy. The stress testing results revealed the instability of brivaracetam under acidic, alkaline, oxidative and thermal stress conditions, while it exhibited relative stability under photolytic stress conditions. CONCLUSION: The study developed an analytical method for brivaracetam that enabled the effective detection and separation of brivaracetam and its 13 degradation products. This method addresses a gap in both current domestic and foreign drug standards. The structures of all the major degradation products were characterized by high-resolution LC/QTOFMS, which is essential for quality control during the drug production process, stability evaluation and the establishment of proper storage conditions.


Assuntos
Pirrolidinonas , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Hidrólise , Cromatografia Líquida/métodos , Oxirredução , Fotólise , Estabilidade de Medicamentos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos
9.
Epilepsy Behav ; 156: 109844, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38788664

RESUMO

OBJECTIVE: We previously analyzed data from three phase lll trials of adjunctive brivaracetam (BRV) in adults showing that the incidence and prevalence of drug-related central nervous system treatment-emergent adverse events (TEAEs) quickly peaked and decreased over several weeks following BRV treatment initiation. However, that analysis did not assess psychiatric and behavioral side effects which can occur with antiseizure medication (ASM) treatment. Here, we investigate the time-course of psychiatric and behavioral TEAEs by week of BRV treatment and how these TEAEs were managed. METHODS: Data were pooled from three trials (N01252 [NCT00490035]; N01253 [NCT00464269]; N01358 [NCT01261325]) in adult patients (≥16 years of age) with focal-onset seizures receiving BRV adjunctive therapy. This post hoc analysis reports data on the incidence and prevalence of drug-related psychiatric or behavioral TEAEs over time in patients who received BRV doses of 50-200 mg/day (without titration) or placebo (PBO) during the 12-week treatment period. A logistic regression model was used to determine if psychiatric or behavioral comorbid conditions were predictors for drug-related psychiatric or behavioral TEAEs, or BRV discontinuation due to psychiatric or behavioral TEAEs. RESULTS: A total of 803 patients received BRV 50-200 mg/day, and 459 patients received PBO. Drug-related psychiatric or behavioral TEAEs were reported by 11.0 % of patients during adjunctive BRV treatment (PBO: 4.8 %) with onset early after BRV initiation (median time to onset of first drug-related psychiatric or behavioral TEAE: 15 days). Incidence peaked at week 1 and decreased over the first 4 weeks following BRV initiation. Prevalence peaked at week 4 and then remained stable between weeks 5-12. In an analysis excluding patients on concomitant levetiracetam (BRV: n = 744; PBO: n = 422), the incidence of drug-related psychiatric or behavioral TEAEs was similar to the incidence in the overall population. The most common drug-related psychiatric or behavioral TEAEs were irritability, insomnia, depression, and anxiety. Only 2 % of patients discontinued BRV due to psychiatric or behavioral TEAEs (PBO: 1.3 %), while most patients on BRV who reported drug-related psychiatric or behavioral TEAEs did not require a change in dose (84.1 %; PBO: 63.6 %). A history of psychiatric or behavioral comorbid conditions (not ongoing at BRV initiation) was not associated with an increased likelihood of drug-related psychiatric or behavioral TEAEs, or BRV discontinuation due to psychiatric or behavioral TEAEs. Ongoing psychiatric or behavioral comorbid conditions at BRV initiation increased the likelihood of drug-related psychiatric or behavioral TEAEs, but not the likelihood of BRV discontinuation due to psychiatric or behavioral TEAEs. CONCLUSIONS: Drug-related psychiatric and behavioral TEAEs occurred early during BRV treatment, and most patients did not require a change in BRV dose. These data can help guide clinician monitoring and patient expectations after starting BRV.


Assuntos
Anticonvulsivantes , Pirrolidinonas , Convulsões , Humanos , Masculino , Adulto , Feminino , Anticonvulsivantes/efeitos adversos , Pirrolidinonas/efeitos adversos , Pirrolidinonas/administração & dosagem , Pirrolidinonas/uso terapêutico , Pessoa de Meia-Idade , Convulsões/induzido quimicamente , Convulsões/epidemiologia , Transtornos Mentais/epidemiologia , Transtornos Mentais/tratamento farmacológico , Transtornos Mentais/induzido quimicamente , Fatores de Tempo , Adulto Jovem , Método Duplo-Cego , Epilepsias Parciais/tratamento farmacológico , Idoso , Adolescente
10.
Epilepsy Behav ; 150: 109561, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38070405

RESUMO

OBJECTIVE: Here we present a multicenter series of patients with developmental epileptic encephalopathies (DEE) who were treated with brivaracetam (BRV) as add-on therapy. METHODS: Medical records of 42 patients with DEE treated with add-on BRV seen at four pediatric neurology centers in Argentina between January 2021 and July 2023 were retrospectively analyzed. RESULTS: We included 42 patients (26 males, 16 females) with a mean age of 7 years (SD, ± 3.8; median, 9; range, 2-16). The children had different types of childhood-onset treatment-resistant DEEs and received BRV as add-on therapy for a mean period of 2 years (SD, ± 1.3 years; median, 1.5 years; range, 0.5-3 years). Thirty-three patients received levetiracetam (LEV) before the introduction of BRV. In nine patients, BRV was started without prior LEV because of behavioral disturbances. Three patients (9.5 %) became seizure free and 26/42 patients (62.1 %) had a greater than 50 % decrease in seizures after a mean follow-up of 21 months. Ten patients (23.8 %) had a 25-50 % seizure reduction, while seizure frequency remained unchanged in two (4.7 %) and increased in one patient (2.4 %). The interictal EEG abnormalities improved in all the responders. Adverse effects, consisting of drowsiness, irritability, and decreased appetite, were observed in seven patients (16.6 %), but did not lead to treatment discontinuation. CONCLUSION: Brivaracetam was found to be effective, safe, and well tolerated in children with DEE. In patients on LEV with behavioral disturbances, BRV may be tried. BRV may also be given without a previous trial with LEV in patients with behavioral problems.


Assuntos
Anticonvulsivantes , Encefalopatias , Masculino , Criança , Feminino , Humanos , Anticonvulsivantes/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento , Pirrolidinonas/efeitos adversos , Levetiracetam/uso terapêutico , Quimioterapia Combinada , Convulsões/tratamento farmacológico
11.
Biometals ; 37(2): 507-517, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38133869

RESUMO

Siderophores are small-molecule iron chelators produced by many microorganisms that capture and uptake iron from the natural environment and host. Their biosynthesis in microorganisms is generally performed using non-ribosomal peptide synthetase (NRPS) or NRPS-independent siderophore (NIS) enzymes. Vibrio parahaemolyticus secretes its cognate siderophore vibrioferrin under iron-starvation conditions. Vibrioferrin is a dehydrated condensate composed of α-ketoglutarate, L-alanine, aminoethanol, and citrate, and pvsA (the gene encoding the ATP-grasp enzyme), pvsB (the gene encoding the NIS enzyme), pvsD (the gene encoding the NIS enzyme), and pvsE (the gene encoding decarboxylase) are engaged in its biosynthesis. Here, we elucidated the biosynthetic pathway of vibrioferrin through in vitro enzymatic reactions using recombinant PvsA, PvsB, PvsD, and PvsE proteins. We also found that PvsD condenses L-serine and citrate to generate O-citrylserine, and that PvsE decarboxylates O-citrylserine to form O-citrylaminoethanol. In addition, we showed that O-citrylaminoethanol is converted to alanyl-O-citrylaminoethanol by amidification with L-Ala by PvsA and that alanyl-O-citrylaminoethanol is then converted to vibrioferrin by amidification with α-ketoglutarate by PvsB.


Assuntos
Pirrolidinonas , Vibrio parahaemolyticus , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/química , Vibrio parahaemolyticus/metabolismo , Vias Biossintéticas , Ácidos Cetoglutáricos/metabolismo , Ferro/metabolismo , Sideróforos/química , Citratos/metabolismo
12.
J Nat Prod ; 87(6): 1521-1531, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38754059

RESUMO

The title marine natural products have been prepared by total synthesis and in the case of congeners 3, 6, and 7 for the first time. Each of these was obtained by manipulation of readily prepared denigrin B (2). The structure, 3, assigned to denigrin C is shown to be incorrect. Reaction of compound 2 with DDQ has led, in high yield, to the related natural product spirodactylone (16), while treating the corresponding permethyl ether 15 with PIFA/BF3·Et2O provides compound 20, embodying an isomeric framework.


Assuntos
Alcaloides , Pirróis , Pirrolidinonas , Estrutura Molecular , Alcaloides/química , Alcaloides/síntese química , Pirróis/síntese química , Pirróis/química , Pirrolidinonas/química , Pirrolidinonas/síntese química , Produtos Biológicos/química , Produtos Biológicos/síntese química , Biologia Marinha , Estereoisomerismo , Animais
13.
J Nat Prod ; 87(6): 1582-1590, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38785214

RESUMO

Bioactivity-based molecular networking-guided fractionation enabled the isolation of three new polycyclic tetramic acids bearing cis-decalin, epicolidines A-C (1-3), along with one known compound, PF 1052 (4), from the endophytic fungus Epicoccum sp. 1-042 collected in Tibet, China. Their structures were assigned on the basis of extensive spectroscopic data, partial hydrolysis, advanced Marfey's method, quantum chemistry calculations, and X-ray diffraction analysis. Compounds 2-4 displayed promising activities against Gram-positive bacteria in vitro. Particularly, compound 4 displayed remarkable potential against vancomycin-resistant Enterococcus faecium (VRE) with an MIC value of 0.25 µg/mL, lower than the MIC (0.5 µg/mL) of the antibiotic combination quinupristin/dalfopristin (Q/D). In a further in vivo study, compound 4 increased the survival rate to 100% in the VRE-G. mellonella infection model at a concentration of 10 mg/kg.


Assuntos
Antibacterianos , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química , Estrutura Molecular , Ascomicetos/química , Tibet , Animais , Enterococcus faecium/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Pirrolidinonas/farmacologia , Pirrolidinonas/química , Pirrolidinonas/isolamento & purificação
14.
Acta Pharmacol Sin ; 45(3): 490-501, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37935896

RESUMO

Oligodendrocytes (OLs) are glial cells that ensheath neuronal axons and form myelin in the central nervous system (CNS). OLs are differentiated from oligodendrocyte precursor cells (OPCs) during development and myelin repair, which is often insufficient in the latter case in demyelinating diseases such as multiple sclerosis (MS). Many factors have been reported to regulate OPC-to-OL differentiation, including a number of G protein-coupled receptors (GPCRs). In an effort to search pathways downstream of GPCRs that might be involved in OPC differentiation, we discover that U73122, a phosphoinositide specific phospholipase C (PI-PLC) inhibitor, dramatically promotes OPC-to-OL differentiation and myelin regeneration in experimental autoimmune encephalomyelitis model. Unexpectedly, U73343, a close analog of U73122 which lacks PI-PLC inhibitory activity also promotes OL differentiation, while another reported PI-PLC inhibitor edelfosine does not have such effect, suggesting that U73122 and U73343 enhance OPC differentiation independent of PLC. Although the structures of U73122 and U73343 closely resemble 17ß-estradiol, and both compounds do activate estrogen receptors Erα and Erß with low efficacy and potency, further study indicates that these compounds do not act through Erα and/or Erß to promote OPC differentiation. RNA-Seq and bioinformatic analysis indicate that U73122 and U73343 may regulate cholesterol biosynthesis. Further study shows both compounds increase 14-dehydrozymostenol, a steroid reported to promote OPC differentiation, in OPC culture. In conclusion, the aminosteroids U73122 and U73343 promote OPC-to-OL generation and myelin formation by regulating cholesterol biosynthesis pathway.


Assuntos
Estrenos , Receptor alfa de Estrogênio , Bainha de Mielina , Pirrolidinonas , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Oligodendroglia/metabolismo , Diferenciação Celular , Colesterol/metabolismo
15.
Mar Drugs ; 22(4)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38667788

RESUMO

A new tetramic acid glycoside, aurantoside L (1), was isolated from the sponge Siliquariaspongia japonica collected at Tsushima Is., Nagasaki Prefecture, Japan. The structure of aurantoside L (1) composed of a tetramic acid bearing a chlorinated polyene system and a trisaccharide part was elucidated using spectral analysis. Aurantoside L (1) showed anti-parasitic activity against L. amazonensis with an IC50 value of 0.74 µM.


Assuntos
Glicosídeos , Leishmania , Poríferos , Poríferos/química , Animais , Glicosídeos/farmacologia , Glicosídeos/química , Glicosídeos/isolamento & purificação , Leishmania/efeitos dos fármacos , Antiprotozoários/farmacologia , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Pirrolidinonas/farmacologia , Pirrolidinonas/química , Pirrolidinonas/isolamento & purificação , Japão , Concentração Inibidora 50
16.
Luminescence ; 39(1): e4609, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37880857

RESUMO

The new drug linagliptin belongs to the class of dipeptidyl peptidase-4 enzyme inhibitors. Linagliptin is used to treat type 2 diabetes and is taken orally either alone or in combination with other drugs. In this instance, a new, simple, and economical technique for analyzing linagliptin was developed by the effective use of a pyrrolidone derivative. The primary amine group of linagliptin permits its condensation with ninhydrin (0.14% w/v) to produce a fluorescent product in the presence of phenylacetaldehyde (0.02% v/v). All experimental parameters were carefully examined and adjusted in order to monitor the generation of the pyrrolidone derivative at excitation and emission wavelengths of 385 and 475 nm, respectively. The calibration graph was made by plotting the intensity of the fluorescence in relation to linagliptin concentration. A significant linearity was found for values ranging from 20 to 460 ng/mL. The process's validity has been verified by a thorough assessment of the instructions provided by the International Conference on Harmonization (ICH). The results indicate excellent uniformity with a reference method, showing that there is no substantial difference in precision and accuracy. The proposed approach was utilized for determining linagliptin in real rat plasma successfully owing to its high sensitivity. Additionally, the proposed approach was evaluated using the Eco-Scale evaluation tool and showed a high degree of eco-friendliness (86/100).


Assuntos
Acetaldeído/análogos & derivados , Diabetes Mellitus Tipo 2 , Linagliptina , Animais , Ratos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Ninidrina/química , Pirrolidinonas
17.
Immunopharmacol Immunotoxicol ; 46(2): 172-182, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38174705

RESUMO

OBJECTIVE: The activation of the NLRP3 inflammasome has been implicated in male infertility. Our study aimed to investigate the therapeutic role of Thiolutin (THL), an inhibitor of the NLRP3 inflammasome, on oligoasthenospermia (OA) and to elucidate its mechanisms. MATERIALS AND METHODS: Semen from 50 OA and 20 healthy males were analyzed to assess the sperm quality and levels of inflammatory markers. Their correlation was determined using Pearson's correlation coefficient. The BALB/c mice were intraperitoneal injected by cyclophosphamide at 60 mg/kg/day for five days to induce OA, followed by a two-week treatment with THL or L-carnitine. Reproductive organ size and H&E staining were determined to observe the organ and seminiferous tubule morphology. ELISA and western blotting were utilized to measure sex hormone levels, inflammatory markers, and NLRP3 inflammasome levels. Furthermore, male and female mice were co-housed to observe pregnancy success rates. RESULTS: OA patients exhibited a decrease in sperm density and motility compared to healthy individuals, along with elevated levels of IL-1ß, IL-18 and NLRP3 inflammasome. In vivo, THL ameliorated OA-induced atrophy of reproductive organs, hormonal imbalance, and improved sperm density, motility, spermatogenesis and pregnancy success rates with negligible adverse effects on weight or liver-kidney function. THL also demonstrated to be able to inhibit the activation of NLRP3 inflammasome and associated proteins in OA mice. DISCUSSION: THL can improve sperm quality and hormonal balance in OA mice through the inhibition of NLRP3 inflammasome activation. Thus, THL holds promising potential as a therapeutic agent for OA.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Masculino , Humanos , Feminino , Camundongos , Animais , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Sêmen/metabolismo , Ciclofosfamida/efeitos adversos , Fertilidade , Espermatozoides/metabolismo , Pirrolidinonas
18.
Int J Mol Sci ; 25(3)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38339112

RESUMO

A series of hydrazones, azoles, and azines bearing a 4-dimethylaminophenyl-5-oxopyrrolidine scaffold was synthesized. Their cytotoxic effect against human pancreatic carcinoma Panc-1 and triple-negative breast cancer MDA-MB-231 cell lines was established by MTT assay. Pyrrolidinone derivatives 3c and 3d, with incorporated 5-chloro and 5-methylbenzimidazole fragments; hydrazone 5k bearing a 5-nitrothien-2-yl substitution; and hydrazone 5l with a naphth-1-yl fragment in the structure significantly decreased the viability of both cancer cell lines. Compounds 3c and 5k showed the highest selectivity, especially against the MDA-MB-231 cancer cell line. The EC50 values of the most active compound 5k against the MDA-MB231 cell line was 7.3 ± 0.4 µM, which were slightly higher against the Panc-1 cell line (10.2 ± 2.6 µM). Four selected pyrrolidone derivatives showed relatively high activity in a clonogenic assay. Compound 5k was the most active in both cell cultures, and it completely disturbed MDA-MB-231 cell colony growth at 1 and 2 µM and showed a strong effect on Panc-1 cell colony formation, especially at 2 µM. The compounds did not show an inhibitory effect on cell line migration by the 'wound-healing' assay. Compound 3d most efficiently inhibited the growth of Panc-1 spheroids and reduced cell viability in MDA-MB-231 spheroids. Considering these different activities in biological assays, the selected pyrrolidinone derivatives could be further tested to better understand the structure-activity relationship and their mechanism of action.


Assuntos
Antineoplásicos , Neoplasias Pancreáticas , Neoplasias de Mama Triplo Negativas , Humanos , Antineoplásicos/uso terapêutico , Relação Estrutura-Atividade , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Proliferação de Células , Hidrazonas/farmacologia , Pirrolidinonas/farmacologia , Linhagem Celular Tumoral , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
19.
Epilepsia ; 64(11): 2934-2946, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37597326

RESUMO

OBJECTIVE: This study was undertaken to evaluate the long-term safety, tolerability, and efficacy of adjunctive brivaracetam (BRV) treatment in pediatric patients with epilepsy. METHODS: A phase 3, open-label, multicenter, long-term follow-up trial (N01266; NCT01364597) was conducted on patients (aged 1 month to <17 years at core trial entry; direct enrollers aged 4 to <17 years) treated with BRV. Outcomes included treatment-emergent adverse events (TEAEs), behavior assessments (Achenbach Child Behavior Checklist [CBCL], Behavior Rating Inventory of Executive Function [BRIEF]/BRIEF-Preschool version [BRIEF-P]), and efficacy outcomes (percent change in focal seizure frequency, 50% responder rate for all seizure types for patient subgroups <2 years and ≥2 years of age using daily record card data). RESULTS: Of 257 patients with ≥1 dose of BRV (141 [54.9%] male; mean age = 8.0 years [SD = 4.5]), 36 patients were <2 years of age, and 72.0% of patients had a history of focal seizures. Mean BRV exposure was 3.2 patient-years. At least one TEAE occurred in 93.4% patients, and 32.3% had serious TEAEs. Seven patients died during the trial; no deaths were considered treatment-related. Patients ≥2 years of age had a median decrease in 28-day adjusted focal seizure frequency of 62.9%, and 50.9% had a ≥50% response in all seizures. Patients <2 years of age had a median decrease in 28-day adjusted focal seizure frequency of 96.9%, and 68.2% had a ≥50% response in all seizures. Kaplan-Meier estimated treatment retention was 72.7%, 64.5%, 57.8%, 53.3%, 50.1%, and 44.8% at 1, 2, 3, 4, 5, and 6 years, respectively. Mean changes (baseline to last evaluation) for all Achenbach CBCL and BRIEF-P/BRIEF subscale scores were negative, reflecting stability/slight improvement. SIGNIFICANCE: Long-term adjunctive BRV treatment was generally well tolerated and efficacious in reducing seizure frequency, and had high retention rates, with generally stable cognitive/behavioral scores in pediatric patients with epilepsy.


Assuntos
Anticonvulsivantes , Epilepsia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Anticonvulsivantes/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada , Epilepsia/tratamento farmacológico , Epilepsia/induzido quimicamente , Seguimentos , Pirrolidinonas/efeitos adversos , Convulsões/tratamento farmacológico , Resultado do Tratamento , Lactente , Adolescente
20.
Epilepsia ; 64(11): 2922-2933, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38079181

RESUMO

OBJECTIVE: This study aimed to explore the effectiveness of brivaracetam (BRV) according to baseline seizure frequency and past treatment history in subjects with focal epilepsy who were included in the Brivaracetam Add-On First Italian Network Study (BRIVAFIRST). METHODS: BRIVAFIRST was a 12-month retrospective, multicenter study including adults prescribed adjunctive BRV. Study outcomes included sustained seizure response (SSR), sustained seizure freedom (SSF), and the rates of treatment discontinuation and adverse events (AEs). Baseline seizure frequency was stratified as <5, 5-20, and >20 seizures per month, and the number of prior antiseizure medications (ASMs) as <5 and ≥6. RESULTS: A total of 994 participants were included. During the 1-year study period, SSR was reached by 45.8%, 39.3%, and 22.6% of subjects with a baseline frequency of <5, 5-20, and >20 seizures per month (p < .001); the corresponding figures for the SSF were 23.4%, 9.8%, and 2.8% (p < .001). SSR was reached by 51.2% and 26.5% participants with a history of 1-5 and ≥6 ASMs (p < .001); the corresponding rates of SSF were 24.7% and 4.5% (p < .001). Treatment discontinuation due to lack of efficacy was more common in participants with >20 seizures compared to those with <5 seizures per month (25.8% vs. 9.3%, p < .001), and in participants with history of ≥6 prior ASMs compared to those with history of 1-5 ASMs (19.6% vs. 12.2%, p = .002). There were no differences in the rates of BRV withdrawal due to AEs and the rates of AEs across the groups of participants defined according to the number of seizures at baseline and the number of prior ASMs. SIGNIFICANCE: The baseline seizure frequency and the number of previous ASMs were predictors of sustained seizure frequency reduction with adjunctive BRV in subjects with focal epilepsy.


Assuntos
Anticonvulsivantes , Epilepsias Parciais , Adulto , Humanos , Anticonvulsivantes/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Quimioterapia Combinada , Convulsões/tratamento farmacológico , Convulsões/induzido quimicamente , Epilepsias Parciais/tratamento farmacológico , Pirrolidinonas/uso terapêutico
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