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Vγ9Vδ2 T lymphocytes are programmed for broad antimicrobial responses with rapid production of Th1 cytokines even before birth, and thus thought to play key roles against pathogens in infants. The process regulating Vδ2 cell acquisition of cytotoxic potential shortly after birth remains understudied. We observed that perforin production in cord blood Vδ2 cells correlates with phenotypes defined by the concomitant assessment of PD-1 and CD56. Bulk RNA sequencing of sorted Vδ2 cell fractions indicated that transcripts related to cytotoxic activity and NK function are enriched in the subset with the highest proportion of perforin+ cells. Among differentially expressed transcripts, IRF8, previously linked to CD8 T cell effector differentiation and NK maturation, has the potential to mediate Vδ2 cell differentiation towards cytotoxic effectors. Our current and past results support the hypothesis that distinct mechanisms regulate Vδ2 cell cytotoxic function before and after birth, possibly linked to different levels of microbial exposure.
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Antígeno CD56 , Linfocitos T CD8-positivos , Citotoxicidad Inmunológica , Receptor de Muerte Celular Programada 1 , Receptores de Antígenos de Linfocitos T gamma-delta , Subgrupos de Linfocitos T , Humanos , Linfocitos T CD8-positivos/inmunología , Citocinas/metabolismo , Sangre Fetal , Perforina/genética , Perforina/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Subgrupos de Linfocitos T/inmunología , Antígeno CD56/metabolismoRESUMEN
BACKGROUND: While the efficacy of neoadjuvant chemotherapy (NACT) in treating triple-negative breast cancer (TNBC) is generally accepted, not all patients derive benefit from this preoperative treatment. Presently, there are no validated biomarkers to predict the NACT response, and previous attempts to develop predictive classifiers based on gene expression data have not demonstrated clinical utility. However, predictive models incorporating biological constraints have shown increased robustness and improved performance compared to agnostic classifiers. METHODS: We used the preoperative transcriptomic profiles from 298 patients with TNBC to train and test a rank-based classifier, k-top scoring pairs, to predict whether the patient will have pathological complete response (pCR) or residual disease (RD) following NACT. To reduce overfitting and enhance the signature's interpretability, we constrained the training process to genes involved in the Notch signaling pathway. Subsequently, we evaluated the signature performance on two independent cohorts with 75 and 71 patients. Finally, we assessed the prognostic value of the signature by examining its association with relapse-free survival (RFS) using KaplanâMeier (KM) survival estimates and a multivariate Cox proportional hazards model. RESULTS: The final signature consists of five gene pairs, whose relative ordering can be predictive of the NACT response. The signature has a robust performance at predicting pCR in TNBC patients with an area under the ROC curve (AUC) of 0.76 and 0.85 in the first and second testing cohorts, respectively, outperforming other gene signatures developed for the same purpose. Additionally, the signature was significantly associated with RFS in an independent TNBC patient cohort even after adjusting for T stage, patient age at the time of diagnosis, type of breast surgery, and menopausal status. CONCLUSION: We introduce a robust gene signature to predict pathological complete response (pCR) in patients with TNBC. This signature applies easily interpretable, rank-based decision rules to genes regulated by the Notch signaling pathway, a known determinant in breast cancer chemoresistance. The robust predictive and prognostic performance of the signature make it a strong candidate for clinical implementation, aiding in the stratification of TNBC patients undergoing NACT.
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Neoplasias de la Mama Triple Negativas , Humanos , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/patología , Terapia Neoadyuvante , Recurrencia Local de Neoplasia , Pronóstico , Transcriptoma/genéticaRESUMEN
We report the transmission of acute myeloid leukemia (AML) undetected at donation from a deceased organ donor to two kidneys and one liver recipients. We reviewed the medical records, and performed molecular analyses and whole exome sequencing (WES) to ascertain AML donor origin and its molecular evolution. The liver recipient was diagnosed 11 months after transplantation and died from complications 2 months later. The two kidney recipients (R1 and R2) were diagnosed 19 and 20 months after transplantation and both received treatment for leukemia. R1 died of complications 11 months after diagnosis, while R2 went into complete remission for 44 months, before relapsing. R2 died 10 months later of complications from allogenic bone marrow transplantation. Microsatellite analysis demonstrated donor chimerism in circulating cells from both kidney recipients. Targeted molecular analyses and medical records revealed NPM1 mutation present in the donor and recipients, while FLT3 was mutated only in R1. These findings were confirmed by WES, which revealed additional founder and clonal mutations, and HLA genomic loss in R2. In conclusion, we report the first in-depth genomic analysis of AML transmission following solid organ transplantation, revealing distinct clonal evolution, and providing a potential molecular explanation for tumor escape.
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Leucemia Mieloide Aguda , Trasplante de Órganos , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Mutación , Proteínas Nucleares/genética , Nucleofosmina , Trasplante de Órganos/efectos adversos , Donantes de TejidosRESUMEN
The Toll-like receptor 4 (TLR4) antagonists, (+)-naloxone and (+)-naltrexone, have been reported to decrease self-administration of opioids in rats and to reduce other preclinical indicators of abuse potential. However, under the self-administration conditions studied, the effects of TLR4 antagonists were not reinforcer selective, questioning the involvement of those receptors and their mediated inflammatory response specifically in opioid abuse. The objectives of the current study were to further characterize the reinforcer specificity of TLR4 antagonism in opioid self-administration and to explore its effects in a preclinical model of craving/relapse. The TLR4 antagonist (+)-naltrexone decreased responding in rats trained to self-administer the µ-opioid receptor agonist remifentanil, but with a potency that was not significantly different from that observed in another group of subjects in which responding was maintained by food reinforcement. Responding reinstated by heroin injection was decreased by (+)-naltrexone; however, a similar reduction was not reproduced with the administration of another TLR4 antagonist, lipopolysaccharide from Rhodobacter sphaeroides, administered into the NAcc shell. Thus, TLR4 antagonists lacked reinforcer selectivity in reducing opioid self-administration and were not uniformly effective in a model of craving/relapse, suggesting limitations on the development of (+)-naltrexone or TLR4 antagonists as treatments for opioid abuse.
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Naltrexona/farmacología , Trastornos Relacionados con Opioides/fisiopatología , Receptor Toll-Like 4/metabolismo , Analgésicos Opioides/metabolismo , Analgésicos Opioides/farmacología , Animales , Condicionamiento Operante/efectos de los fármacos , Heroína/administración & dosificación , Masculino , Naloxona/farmacología , Antagonistas de Narcóticos/farmacología , Ratas , Ratas Sprague-Dawley , Refuerzo en Psicología , Autoadministración , Receptor Toll-Like 4/antagonistas & inhibidores , Receptor Toll-Like 4/fisiologíaRESUMEN
Evidence shows that maternal care and postnatal traumatic events can exert powerful effects on brain circuitry development but little is known about the impact of early postnatal experiences on processing of rewarding and aversive stimuli related to the medial prefrontal cortex (mpFC) function in adult life. In this study, the unstable maternal environment induced by repeated cross-fostering (RCF) impaired palatable food conditioned place preference and disrupted the natural preference for sweetened fluids in the saccharin preference test. By contrast, RCF increased sensitivity to conditioned place aversion (CPA) and enhanced immobility in the forced swimming test. Intracerebral microdialysis data showed that the RCF prevents mpFC dopamine (DA) outflow regardless of exposure to rewarding or aversive stimuli, whereas it induces a strong and sustained prefrontal norepinephrine (NE) release in response to different aversive experiences. Moreover, the selective mpFC NE depletion abolished CPA, thus indicating that prefrontal NE is required for motivational salience attribution to aversion-related stimuli. These findings demonstrate that an unstable maternal environment impairs the natural propensity to seek pleasurable sources of reward, enhances sensitivity to negative events in adult life, blunts prefrontal DA outflow, and modulates NE release in the reverse manner depending on the exposure to rewarding or aversive stimuli.
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Conducta Animal/fisiología , Privación Materna , Corteza Prefrontal/fisiopatología , Recompensa , Estrés Psicológico/complicaciones , Envejecimiento , Animales , Animales Recién Nacidos , Dopamina/metabolismo , Femenino , Ratones , Microdiálisis , Norepinefrina/metabolismo , Corteza Prefrontal/metabolismoRESUMEN
We investigated the impact of antiviral treatment on the emergence of SARS-CoV-2 resistance during persistent infections in immunocompromised patients (n=15). All patients received remdesivir and some also received nirmatrelvir-ritonavir or monoclonal antibodies. Sequence analysis showed that nine patients carried viruses with mutations in the nsp12 (RNA dependent RNA polymerase), while four had viruses with nsp5 (3C protease) mutations. Infectious SARS-CoV-2 with a double mutation in nsp5 (T169I) and nsp12 (V792I) was recovered from respiratory secretions 77 days after initial COVID-19 diagnosis from a patient treated with remdesivir and nirmatrelvir-ritonavir. In vitro characterization confirmed its decreased sensitivity to remdesivir and nirmatrelvir, which was overcome by combined antiviral treatment. Studies in golden Syrian hamsters demonstrated efficient transmission to contact animals. This study documents the isolation of SARS-CoV-2 carrying resistance mutations to both nirmatrelvir and remdesivir from a patient and demonstrates its transmissibility in vivo.
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INTRODUCTION: Detection of malignant cells in serous fluids is an indicator of advanced stage of malignancy and is critical in clinical management decisions and prompt treatment initiation. The minimum volume which is ideal for detecting malignancy in serous fluid is not well established. In this study, we aim to identify optimal volume that will be ideal for adequate cytopathological diagnosis. MATERIALS AND METHODS: A total of 1597 samples of serous fluids from 1134 patients were included in the study. Samples were diagnosed based on International System for Reporting Serous Fluid Cytopathology (ISRSFC). Clinicopathologic results from different diagnostic groups were compared and statistically analyzed. RESULTS: Pleural fluids comprised 890 (55.7%) specimens, followed by 456 (28.6%) peritoneal, 128 (8%) ascites, and 123 (7.7%) pericardial fluid specimens. The majority were negative for malignancy (1138, 71.3%), followed by malignant (376, 23.5%), atypical (59, 3.7%), and suspicious for malignancy (24, 1.5%). Malignancy was identified in sample with volumes from 5 mL to 5000 mL. Rate of detection of malignant cells increased significantly with higher sample volumes. For malignancy detection the optimal volume for overall serous fluid is 70 mL. Pericardial fluid is an exception, with lower mean volume and significantly lower proportion of cases with malignant diagnosis. CONCLUSIONS: Our study indicates that higher fluid volumes have a higher rate of malignancy detection and a low false-negative rate. We recommend a minimum of 70 mL of serous fluid for optimal cytopathologic examination and malignancy detection. Pericardial fluid is an exception, with lower mean volume and thus lower requirement.
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Neoplasias , Humanos , Neoplasias/diagnóstico , Neoplasias/patología , Exudados y Transudados , Peritoneo/patología , CitologíaRESUMEN
Immunotherapy is now an integral aspect of cancer therapy. Strategies employing adoptive cell therapy (ACT) have seen the establishment of chimeric antigen receptor (CAR)-T cells using peripheral blood lymphocytes as well as tumor infiltrating lymphocytes (TILs) with significant clinical results. Despite these successes, the limitations of the current strategies are also emerging and novel approaches are needed. The bone marrow (BM) is an immunological niche that houses T cells with specificity for previously encountered antigens, including tumor-associated antigens from certain solid cancers. This study sought to improve our understanding of tumor-specific BM T cells in the context of solid tumors by comparing them with TILs, and to assess whether there is a rationale for using the BM as a source of T cells for ACT against solid malignancies. Herein, we demonstrate that T cells from the BM appear superior to TILs as a source of cells for cellular therapy. Specifically, they possess a memory-enriched phenotype and exhibit improved effector function, greater persistence within a tumor-bearing host, and the capacity for increased tumor infiltration. Taken together, these data provide a foundation for further exploring the BM as a source of tumor-specific T cells for ACT in solid malignancies.
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Many gene signatures have been developed by applying machine learning (ML) on omics profiles, however, their clinical utility is often hindered by limited interpretability and unstable performance. Here, we show the importance of embedding prior biological knowledge in the decision rules yielded by ML approaches to build robust classifiers. We tested this by applying different ML algorithms on gene expression data to predict three difficult cancer phenotypes: bladder cancer progression to muscle-invasive disease, response to neoadjuvant chemotherapy in triple-negative breast cancer, and prostate cancer metastatic progression. We developed two sets of classifiers: mechanistic, by restricting the training to features capturing specific biological mechanisms; and agnostic, in which the training did not use any a priori biological information. Mechanistic models had a similar or better testing performance than their agnostic counterparts, with enhanced interpretability. Our findings support the use of biological constraints to develop robust gene signatures with high translational potential.
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We evaluated the performance of SARS-CoV-2 TaqMan real-time reverse-transcription PCR (RT-qPCR) assays (ThermoFisher) for detecting 2 nonsynonymous spike protein mutations, E484K and N501Y. Assay accuracy was evaluated by whole genome sequencing (WGS). Residual nasopharyngeal SARS-CoV-2 positive samples (N = 510) from a diverse patient population in New York City submitted for routine SARS-CoV-2 testing during January-April 2020 were used. We detected 91 (18%) N501Y and 101 (20%) E484K variants. Four samples (0.8%) were positive for both variants. The assay had nearly perfect concordance with WGS in the validation subset, detecting B.1.1.7 and B.1.526 variants among others. Sensitivity and specificity ranged from 0.95 to 1.00. Positive and negative predictive values were 0.98-1.00. TaqMan genotyping successfully predicted the presence of B.1.1.7, but had significantly lower sensitivity, 62% (95% CI, 0.53, 0.71), for predicting B.1.526 sub-lineages lacking E484K. This approach is rapid and accurate for detecting SARS-CoV-2 variants and can be rapidly implemented in routine clinical setting.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Prueba de COVID-19 , Polimorfismo de Nucleótido Simple , Genotipo , COVID-19/diagnóstico , MutaciónRESUMEN
Targeting lineage-defined transcriptional dependencies has emerged as an effective therapeutic strategy in cancer treatment. Through screening for molecular vulnerabilities of mantle cell lymphoma (MCL), we identified a set of transcription factors (TFs) including FOXO1, EBF1, PAX5, and IRF4 that are essential for MCL propagation. Integrated chromatin immunoprecipitation and sequencing (ChIP-Seq) with transcriptional network reconstruction analysis revealed FOXO1 as a master regulator that acts upstream in the regulatory TF hierarchy. FOXO1 is both necessary and sufficient to drive MCL lineage commitment through supporting the lineage-specific transcription programs. We further show that FOXO1, but not its close paralog FOXO3, can reprogram myeloid leukemia cells and induce B-lineage gene expression. Finally, we demonstrate that cpd10, a small molecule identified from an enriched FOXO1 inhibitor library, induces a robust cytotoxic response in MCL cells in vitro and suppresses MCL progression in vivo. Our findings establish FOXO1 inhibition as a therapeutic strategy targeting lineage-driven transcriptional addiction in MCL.
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Linfoma de Células del Manto , Humanos , Adulto , Linfoma de Células del Manto/genética , Redes Reguladoras de Genes , Proteína Forkhead Box O1/genéticaRESUMEN
INTRODUCTION: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic revealed a worldwide lack of effective molecular surveillance networks at local, state, and national levels, which are essential to identify, monitor, and limit viral community spread. SARS-CoV-2 variants of concern (VOCs) such as Alpha and Omicron, which show increased transmissibility and immune evasion, rapidly became dominant VOCs worldwide. Our objective was to develop an evidenced-based genomic surveillance algorithm, combining reverse transcription polymerase chain reaction (RT-PCR) and sequencing technologies to quickly identify highly contagious VOCs, before cases accumulate exponentially. METHODS: Deidentified data were obtained from 508,969 patients tested for coronavirus disease 2019 (COVID-19) with the TaqPath COVID-19 RT-PCR Combo Kit (ThermoFisher) in four CLIA-certified clinical laboratories in Puerto Rico (n = 86,639) and in three CLIA-certified clinical laboratories in the United States (n = 422,330). RESULTS: TaqPath data revealed a frequency of S Gene Target Failure (SGTF) > 47% for the last week of March 2021 in both, Puerto Rico and US laboratories. The monthly frequency of SGTF in Puerto Rico steadily increased exponentially from 4% in November 2020 to 47% in March 2021. The weekly SGTF rate in US samples was high (>8%) from late December to early January and then also increased exponentially through April (48%). The exponential increase in SGFT prevalence in Puerto Rico was concurrent with a sharp increase in VOCs among all SARS-CoV-2 sequences from Puerto Rico uploaded to Global Influenza Surveillance and Response System (GISAID) (n = 461). Alpha variant frequency increased from <1% in the last week of January 2021 to 51.5% of viral sequences from Puerto Rico collected in the last week of March 2021. CONCLUSIONS: According to the proposed evidence-based algorithm, approximately 50% of all SGTF patients should be managed with VOCs self-quarantine and contact tracing protocols, while WGS confirms their lineage in genomic surveillance laboratories. Our results suggest this workflow is useful for tracking VOCs with SGTF.
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COVID-19 , SARS-CoV-2 , Secuencia de Bases , COVID-19/diagnóstico , COVID-19/epidemiología , Humanos , Medicina de Precisión , SARS-CoV-2/genética , Estados Unidos/epidemiologíaRESUMEN
Mice born from high care-giving females show, as adults, low anxiety levels, decreased responsiveness to stress, and substantial improvements in cognitive function and hippocampal plasticity. Given the relevance of this issue for preventing emotional and cognitive abnormalities in high-risk subjects, this study examines the possibility to further enhance the beneficial effects observed in the progeny by augmenting maternal care beyond the highest levels females can display in standard laboratory conditions. This was produced by placing a second female with the dam and its litter in the rearing cage from the partum until pups weaning. Maternal behavior of all females was scored during the first week postpartum, and behavioral indices of emotionality, prestress and poststress corticosterone levels, cognitive performance, and hippocampal morphology were assessed in the adult offspring. We found that pups reared by female dyads received more maternal care than pups reared by dams alone, but as adults, they did not exhibit alterations in emotionality or corticosterone response estimated in basal condition or following restraint stress. Conversely, they showed enhanced performance in hippocampal-dependent tasks including long-term object discrimination, reactivity to spatial change, and fear conditioning together with an increase in dendritic length and spine density in the CA1 region of the hippocampus. In general, the beneficial effects of dyadic maternal care were stronger when both the females were lactating. This study demonstrates that double-mothering exerts a long-term positive control on cognitive function and hippocampal neuronal connectivity. This experimental manipulation, especially if associated with increased feeding, might offer a concrete possibility to limit or reverse the consequences of negative predisposing conditions for normal cognitive development.
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Conducta Animal/fisiología , Región CA1 Hipocampal , Cognición/fisiología , Espinas Dendríticas/metabolismo , Conducta Materna/fisiología , Estrés Psicológico , Corteza Visual , Animales , Animales Recién Nacidos , Región CA1 Hipocampal/citología , Región CA1 Hipocampal/metabolismo , Corticosterona/sangre , Femenino , Vivienda para Animales , Lactancia/fisiología , Masculino , Conducta Materna/psicología , Ratones , Madres , Periodo Posparto , Embarazo , Corteza Visual/citología , Corteza Visual/metabolismoRESUMEN
Since the beginning of the coronavirus disease-2019 (COVID-19) pandemic in 2020, there has been a tremendous accumulation of data capturing different statistics including the number of tests, confirmed cases and deaths. This data wealth offers a great opportunity for researchers to model the effect of certain variables on COVID-19 morbidity and mortality and to get a better understanding of the disease at the epidemiological level. However, in order to draw any reliable and unbiased estimate, models also need to take into account other variables and metrics available from a plurality of official and unofficial heterogenous resources. In this study, we introduce covid19census, an R package that extracts from many different repositories and combines together COVID-19 metrics and other demographic, environment- and health-related variables of the USA and Italy at the county and regional levels, respectively. The package is equipped with a number of user-friendly functions that dynamically extract the data over different timepoints and contains a detailed description of the included variables. To demonstrate the utility of this tool, we used it to extract and combine different county-level data from the USA, which we subsequently used to model the effect of diabetes on COVID-19 mortality at the county level, taking into account other variables that may influence such effects. In conclusion, it was observed that the 'covid19census' package allows to easily extract area-level data from both the USA and Italy using few functions. These comprehensive data can be used to provide reliable estimates of the effect of certain variables on COVID-19 outcomes. Database URL: https://github.com/c1au6i0/covid19census.
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COVID-19/epidemiología , Bases de Datos Factuales , Conjuntos de Datos como Asunto , Pandemias , SARS-CoV-2 , Algoritmos , Comorbilidad , Demografía , Diabetes Mellitus/mortalidad , Encuestas Epidemiológicas , Humanos , Italia/epidemiología , Modelos Teóricos , Programas Informáticos , Estados Unidos/epidemiologíaRESUMEN
The COVID-19 mortality rate is higher in the elderly and in those with pre-existing chronic medical conditions. The elderly also suffer from increased morbidity and mortality from seasonal influenza infections; thus, an annual influenza vaccination is recommended for them. In this study, we explore a possible county-level association between influenza vaccination coverage in people aged 65 years and older and the number of deaths from COVID-19. To this end, we used COVID-19 data up to 14 December 2020 and US population health data at the county level. We fit quasi-Poisson regression models using influenza vaccination coverage in the elderly population as the independent variable and the COVID-19 mortality rate as the outcome variable. We adjusted for an array of potential confounders using different propensity score regression methods. Results show that, on the county level, influenza vaccination coverage in the elderly population is negatively associated with mortality from COVID-19, using different methodologies for confounding adjustment. These findings point to the need for studying the relationship between influenza vaccination and COVID-19 mortality at the individual level to investigate any underlying biological mechanisms.
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COVID-19 mortality rate is higher in the elderly and in those with preexisting chronic medical conditions. The elderly also suffer from increased morbidity and mortality from seasonal influenza infection, and thus annual influenza vaccination is recommended for them. In this study, we explore a possible area-level association between influenza vaccination coverage in people aged 65 years and older and the number of deaths from COVID-19. To this end, we used COVID-19 data until June 10, 2020 together with population health data for the United States at the county level. We fit quasi-Poisson regression models using influenza vaccination coverage in the elderly population as the independent variable and the number of deaths from COVID-19 as the outcome variable. We adjusted for a wide array of potential confounding variables using both county-level generalized propensity scores for influenza vaccination rates, as well as direct adjustment. Our results suggest that influenza vaccination coverage in the elderly population is negatively associated with mortality from COVID-19. This finding is robust to using different analysis periods, different thresholds for inclusion of counties, and a variety of methodologies for confounding adjustment. In conclusion, our results suggest a potential protective effect of the influenza vaccine on COVID-19 mortality in the elderly population. The significant public health implications of this possibility point to an urgent need for studying the relationship between influenza vaccination and COVID-19 mortality at the individual level, to investigate both the epidemiology and any underlying biological mechanism.
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The neuropeptide oxytocin (OT) alters behaviors related to the administration of drugs of abuse, including stimulants. OT also plays a key role in social bonding, which involves an interaction between OT and dopamine (DA) in the nucleus accumbens (NAc). The nature of the interaction between OT and DA in the striatum in the context of psychostimulants is unclear. We investigated the effect of OT, delivered intraperitoneally, on the methylphenidate (MP) dose-response function for self-administration in rats. Food was used as a control condition. In a microdialysis study, we measured the effect of intraperitoneal OT on MP-stimulated striatal DA levels. Systemic OT pretreatment caused a downward shift in the MP dose-response function for self-administration, while having no effect on motor activity. OT also caused a reduction in food self-administration, although a significantly higher dose of OT was required for this effect compared with that required for a reduction of MP self-administration. Systemic OT pretreatment caused a potentiation of MP-stimulated DA levels in the NAc shell but not in the core. The significance of these findings is discussed, including the potential of OT as a therapeutic agent for addictive disorders.
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Dopamina/metabolismo , Metilfenidato/administración & dosificación , Oxitocina/administración & dosificación , Animales , Relación Dosis-Respuesta a Droga , Ratas , Ratas Sprague-Dawley , AutoadministraciónRESUMEN
Atypical dopamine uptake inhibitors (DUIs) bind to the dopamine transporter and inhibit the reuptake of dopamine but have lower abuse potential than psychostimulants. Several atypical DUIs can block abuse-related effects of cocaine and methamphetamine, thus making them potential medication candidates for psychostimulant use disorders. The aim of the current study is to establish an in-vivo assay using EEG for the rapid identification of atypical DUIs with potential for medication development. The typical DUIs cocaine and methylphenidate dose-dependently decreased the power of the alpha, beta, and gamma bands. The atypical DUI modafinil and its F-analog, JBG1-049, decreased the power of beta, but in contrast to cocaine, none of the other frequency bands, while JHW007 did not significantly alter the EEG spectrum. The mu-opioid receptor agonists heroin and morphine dose-dependently decreased the power of gamma and increased power of the other bands. The effect of morphine on EEG power bands was antagonized by naltrexone. The NMDA receptor antagonist ketamine increased the power of all frequency bands. Therefore, typical and atypical DUIs and drugs of other classes differentially affected EEG spectra, showing distinctive features in the magnitude and direction of their effects on EEG. Comparative analysis of the effects of test drugs on EEG indicates a potential atypical profile of JBG1-049 with similar potency and effectiveness to its parent compound modafinil. These data suggest that EEG can be used to rapidly screen compounds for potential activity at specific pharmacological targets and provide valuable information for guiding the early stages of drug development. This article is part of the issue entitled 'Special Issue on Neurotransmitter Transporters'.
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Fármacos del Sistema Nervioso Central/farmacología , Inhibidores de Captación de Dopamina/farmacología , Electroencefalografía/efectos de los fármacos , Animales , Cocaína/farmacología , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Heroína/farmacología , Ketamina/farmacología , Masculino , Metilfenidato/farmacología , Modafinilo/farmacología , Morfina/farmacología , Naltrexona/farmacología , Antagonistas de Narcóticos/farmacología , Narcóticos/farmacología , Ratas , Ratas Sprague-Dawley , Receptores Opioides mu/agonistasRESUMEN
Recent discoveries have improved our understanding of the physiological and pathological roles of the dopamine transporter (DAT); however, only a few drugs are clinically available for DAT-implicated disorders. Among those drugs, modafinil (MOD) and its ( R)-enantiomer (R-MOD) have been used off-label as therapies for psychostimulant use disorders, but they have shown limited effectiveness in clinical trials. Recent preclinical studies on MOD and R-MOD have led to chemically modified structures aimed toward improving their neurobiological properties that might lead to more effective therapeutics for stimulant use disorders. This study examines three MOD analogues (JJC8-016, JJC8-088, and JJC8-091) with improved DAT affinities compared to their parent compound. These compounds were investigated for their effects on the neurochemistry (brain microdialysis and FSCV) and behavior (ambulatory activity) of male Swiss-Webster mice. Our data indicate that these compounds have dissimilar effects on tonic and phasic dopamine in the nucleus accumbens shell and variability in producing ambulatory activity. These results suggest that small changes in the chemical structure of a DAT inhibitor can cause compounds such as JJC8-088 to produce effects similar to abused psychostimulants like cocaine. In contrast, other compounds like JJC8-091 do not share cocaine-like effects and have a more atypical DAT-inhibitor profile, which may prove to be an advancement in the treatment of psychostimulant use disorders.
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Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/antagonistas & inhibidores , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Microdiálisis/métodos , Modafinilo/química , Modafinilo/farmacología , Núcleo Accumbens/metabolismo , Animales , Dopamina/metabolismo , Inhibidores de Captación de Dopamina/farmacología , Relación Dosis-Respuesta a Droga , Masculino , Ratones , Núcleo Accumbens/efectos de los fármacos , EstereoisomerismoRESUMEN
RATIONALE AND OBJECTIVES: Benztropine (BZT) analogs and other atypical dopamine uptake inhibitors selectively decrease cocaine self-administration at doses that do not affect responding maintained by other reinforcers. Those effects were further characterized in the current study using a behavioral economic assessment of how response requirement (price) affects reinforcers obtained (consumption) in rats. METHODS: Two groups of rats were trained to press levers with food (45-mg pellet) or cocaine (0.32 mg/kg/injection) reinforcement under fixed-ratio (FR) 5-response schedules. In selected sessions, the FR requirement was increased (5-80) during successive 20-min components to determine demand curves, which plot consumption against price. An exponential function was fitted to the data to derive the consumption at zero price (Q 0) and the rate of decrease in consumption (essential value, EV) with increased price. The BZT analogs, AHN1-055, AHN2-005, JHW007 (3.2-10 or 17.8 mg/kg, each), vehicle, or comparison drugs (methylphenidate, ketamine), were administered i.p. before selected demand-curve determinations. RESULTS: Consumption of cocaine or food decreased with increased FR requirement. Each drug shifted the demand curve rightward at the lowest doses and leftward/downward at higher doses. The effects on EV and Q 0 were greater for cocaine than for food-reinforced responding. Additionally, the effects of the BZT analogs on EV and Q 0 were greater than those obtained with a standard dopamine transport inhibitor, methylphenidate, and the NMDA antagonist, ketamine (1.0-10.0 mg/kg, each). With these latter drugs, the demand-curve parameters were affected similarly with cocaine and food-maintained responding. CONCLUSIONS: The current findings, obtained using a behavioral economic assessment, suggest that BZT analogs selectively decrease the reinforcing effectiveness of cocaine.