RESUMEN
Higher sensitivity to reward (SR) and weaker sensitivity to punishment (SP) construct the fundamental craving characteristics of methamphetamine abuse. However, few studies have appraised relationships between SR/SP (SR or SP) and cortical morphological alterations in methamphetamine abusers and whether hereditary factors take effects on SR/SP is unclear. Based on surface-based morphometric analysis, cortical discrepancy was investigated between 38 methamphetamine abusers and 37 healthy controls. Within methamphetamine abusers, correlation profiling was performed to discover associations among aberrant neuroimaging substrates, SR, SP, and craving. According to nine single nucleotide polymorphism sites of dopamine-related genes, we conducted univariate general linear model to find different effects of genotypes on cortical alterations and SR/SP/craving (SR, SP, or craving). Ultimately, mediation analyses were conducted among single nucleotide polymorphism sites, SR/SP/craving, and cortical morphological alterations to discover their association pathways. Compared to healthy controls, thinner cortices in inferior temporal gyrus, lateral orbitofrontal cortex, medial orbitofrontal cortex, inferior parietal lobule, and lateral occipital cortex in the left hemisphere were found in methamphetamine abusers (P < 0.05, family-wise error corrected). Cortical thickness in the inferior temporal gyrus was negatively correlated with SR scores. We found that rs1800497 A-containing genotypes had lower cortical thickness in the left inferior parietal lobule than the GG genotype. The rs5751876 had effects on SR scores. This study would provide convincing biomarkers for SR in methamphetamine abusers and offer potential genetic targets for personalizing relapse prevention.
Asunto(s)
Trastornos Relacionados con Anfetaminas , Corteza Cerebral , Imagen por Resonancia Magnética , Metanfetamina , Polimorfismo de Nucleótido Simple , Recompensa , Humanos , Masculino , Adulto , Trastornos Relacionados con Anfetaminas/genética , Trastornos Relacionados con Anfetaminas/diagnóstico por imagen , Trastornos Relacionados con Anfetaminas/patología , Metanfetamina/efectos adversos , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Femenino , Adulto Joven , Síndrome de Abstinencia a Sustancias/genética , Síndrome de Abstinencia a Sustancias/patología , Síndrome de Abstinencia a Sustancias/psicología , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Ansia/fisiología , CastigoRESUMEN
Individuals with methamphetamine use disorder (MUD) often experience anxiety and depressive symptoms during abstinence, which can worsen the likelihood of relapse. Thus, it is essential to understand the neuro-mechanism behind methamphetamine use and its associated emotional withdrawal symptoms in order to develop effective clinical strategies. This study aimed to evaluate associations between emotional withdrawal symptoms and structural covariance networks (SCNs) based on cortical thickness (CTh) across the brain. The CTh measures were obtained from Tl-weighted MRI data from a sample of 48 males with MUD during abstinence and 48 male healthy controls. The severity of anxiety and depressive symptoms was assessed by the Hamilton Anxiety Scale (HAMA) and depression (HAMD) scales. Two important nodes belonging to the brain reward system, the right rostral anterior cingulate cortex (rACC) and medial prefrontal cortex (medPFC), were selected as seeds to conduct SCNs and modulation analysis by emotional symptoms. MUDs showed higher structural covariance between the right rACC and regions in the dorsal attention, right frontoparietal, auditory, visual and limbic networks. They also displayed higher structural covariance between the right medPFC and regions in the limbic network. Moreover, the modulation analysis showed that higher scores on HAMA were associated with increased covariance between the right rACC and the left parahippocampal and isthmus cingulate cortex in the default mode network. These outcomes shed light on the complex neurobiological mechanisms underlying methamphetamine use and its associated emotional withdrawal symptoms and may provide new insights into the development of effective treatments for MUD.
Asunto(s)
Emociones , Síndrome de Abstinencia a Sustancias , Humanos , Masculino , Encéfalo/diagnóstico por imagen , Ansiedad/diagnóstico por imagen , Imagen por Resonancia Magnética , Mapeo Encefálico , Síndrome de Abstinencia a Sustancias/diagnóstico por imagenRESUMEN
Chronic alcohol use increases risk of alcohol withdrawal symptoms (AW) and disrupts stress biology and resilient coping, thereby promoting excessive alcohol intake. Chronic alcohol intake and multiple alcohol detoxifications are known to impair brain medial prefrontal cortex (mPFC) and striatal functioning, regions involved in regulating stress, craving and alcohol intake. In two related studies, we examined whether AW predicts this functional brain pathology and whether Prazosin versus Placebo treatment may reverse these effects. In Study 1, patients with Alcohol Use Disorder (AUD) (N = 45) with varying AW levels at treatment entry were assessed to examine AW effects on corticostriatal responses to stress, alcohol cue and neutral visual images with functional magnetic resonance imaging (fMRI). In Study 2, 23 AUD patients entering a 12-week randomised controlled trial (RCT) of Prazosin, an alpha1 adrenergic antagonist that decreased withdrawal-related alcohol intake in laboratory animals, participated in two fMRI sessions at pretreatment and also at week 9-10 of chronic treatment (Placebo: N = 13; Prazosin: N = 10) to assess Prazosin treatment effects on alcohol-related cortico-striatal dysfunction. Study 1 results indicated that higher AW predicted greater disruption in brain mPFC and striatal response to stress and alcohol cues (p < 0.001, family-wise error [FWE] correction) and also subsequently greater heavy drinking days (HDD) in early treatment (p < 0.01). In Study 2, Prazosin versus Placebo treatment reversed mPFC-striatal dysfunction (p < 0.001, FWE), which in turn predicted fewer drinking days (p < 0.01) during the 12-week treatment period. These results indicate that AW is a significant predictor of alcohol-related prefrontal-striatal dysfunction, and Prazosin treatment reversed these effects that in turn contributed to improved alcohol treatment outcomes.
Asunto(s)
Alcoholismo , Síndrome de Abstinencia a Sustancias , Consumo de Bebidas Alcohólicas , Alcoholismo/diagnóstico por imagen , Alcoholismo/tratamiento farmacológico , Ansia/fisiología , Humanos , Prazosina/farmacología , Prazosina/uso terapéutico , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Síndrome de Abstinencia a Sustancias/tratamiento farmacológicoRESUMEN
As a critical component of cortico-striato-thalamo-cortical loop in addiction, our understanding of the thalamus in impaired cognition of heroin users (HU) has been limited. Due to the complex thalamic connection with cortical and subcortical regions, thalamus was divided into prefrontal (PFC), occipital (OC), premotor, primary motor, sensory, temporal, and posterior parietal association subregions according to white matter tractography. We adopted seven subregions of bilateral thalamus as regions of interest to systematically study the implications of distinct thalamic nuclei in acute abstinent HU. The volume and resting-state functional connectivity (RSFC) differences of the thalamus were investigated between age-, gender-, and alcohol-matched 37 HU and 33 healthy controls (HCs). Trail making test-A (TMT-A) was adopted to assess cognitive function deficits, which were then correlated with neuroimaging findings. Although no significant different volumes were found, HU group showed decreased RSFC between left PFC_thalamus and middle temporal gyrus as well as between left OC_thalamus and inferior frontal gyrus and supplementary motor area relative to HCs. Meanwhile, the higher TMT-A scores in HU were negatively correlated with PFC_thalamic RSFC with inferior temporal gyrus, fusiform, and precuneus. Craving scores were negatively correlated with OC_thalamic RSFC with accumbens, hippocampus, and insula. Opiate Withdrawal Scale scores were negatively correlated with left PFC/OC_thalamic RSFC with orbitofrontal cortex and medial PFC. We indicated two thalamus subregions separately involvement in cognitive control and craving to reveal the implications of thalamic subnucleus in pathology of acute abstinent HU.
Asunto(s)
Corteza Cerebral/fisiopatología , Conectoma , Dependencia de Heroína/fisiopatología , Red Nerviosa/fisiopatología , Síndrome de Abstinencia a Sustancias/fisiopatología , Tálamo/fisiopatología , Enfermedad Aguda , Adulto , Corteza Cerebral/diagnóstico por imagen , Femenino , Dependencia de Heroína/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Red Nerviosa/diagnóstico por imagen , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Tálamo/diagnóstico por imagenRESUMEN
Anxiety and depression are the most common withdrawal symptoms of methamphetamine (METH) abuse, which further exacerbate relapse of METH abuse. To date, no effective pharmacotherapy exists for METH abuse and its withdrawal symptoms. Therefore, understanding the neuromechanism underlying METH abuse and its withdrawal symptoms is essential for developing clinical strategies and improving patient care. The aims of this study were to investigate brain network abnormalities in METH abusers (MAs) and their associations with affective symptoms. Forty-eight male abstinent MAs and 48 age-gender matched healthy controls were recruited and underwent resting state functional magnetic resonance imaging (fMRI). The severity of patient anxiety and depressive symptoms were measured by Hamilton anxiety and depression rating scales, which decreased across the duration of abstinence. Independent component analysis was used to investigate the brain network functional connectivity (FC) properties. Compared with healthy controls, MAs demonstrated hypo-intra-network FC in the cerebellar network and hyper-intra-network FC in the posterior salience network. A whole-brain regression analysis revealed that FC strength of clusters located in the right rostral anterior cingulate cortex (rACC) within the ventromedial network (VMN) was associated with affective symptoms in the patients. Importantly, the intra-network FC strength of the rACC in VMN mediated the association between abstinence duration and the severity level of affective symptoms. Our results demonstrate alterations in brain functional networks underlying METH abuse, and that the FC of rACC within VMN serve as a neural substrate in the association between abstinence length and affective symptom severity in the MAs.
Asunto(s)
Trastornos Relacionados con Anfetaminas/fisiopatología , Ansiedad/fisiopatología , Estimulantes del Sistema Nervioso Central/efectos adversos , Corteza Cerebral/fisiopatología , Conectoma , Depresión/fisiopatología , Metanfetamina/efectos adversos , Red Nerviosa/fisiopatología , Síndrome de Abstinencia a Sustancias/fisiopatología , Sustancia Blanca/fisiopatología , Adulto , Trastornos Relacionados con Anfetaminas/complicaciones , Trastornos Relacionados con Anfetaminas/diagnóstico por imagen , Ansiedad/diagnóstico por imagen , Ansiedad/etiología , Corteza Cerebral/diagnóstico por imagen , Depresión/diagnóstico por imagen , Depresión/etiología , Humanos , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/diagnóstico por imagen , Síndrome de Abstinencia a Sustancias/complicaciones , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Adulto JovenRESUMEN
Although 60% of the US population have tried smoking cigarettes, only 16% smoke regularly. Identifying this susceptible subset of the population before the onset of nicotine dependence may encourage targeted early interventions to prevent regular smoking and/or minimize severity. While prospective neuroimaging in human populations can be challenging, preclinical neuroimaging models before chronic nicotine administration can help to develop translational biomarkers of disease risk. Chronic, intermittent nicotine (0, 1.2, or 4.8 mg/kg/d; N = 10-11/group) was administered to male Sprague Dawley rats for 14 d; dependence severity was quantified using precipitated withdrawal behaviors collected before, during, and following forced nicotine abstinence. Resting-state fMRI functional connectivity (FC) before drug administration was subjected to a graph theory analytical framework to form a predictive model of subsequent individual differences in nicotine dependence. Whole-brain modularity analysis identified five modules in the rat brain. A metric of intermodule connectivity, participation coefficient, of an identified insular-frontal cortical module predicted subsequent dependence severity, independent of nicotine dose. To better spatially isolate this effect, this module was subjected to a secondary exploratory modularity analysis, which segregated it into three submodules (frontal-motor, insular, and sensory). Higher FC among these three submodules and three of the five originally identified modules (striatal, frontal-executive, and sensory association) also predicted dependence severity. These data suggest that predispositional, intrinsic differences in circuit strength between insular-frontal-based brain networks before drug exposure may identify those at highest risk for the development of nicotine dependence.SIGNIFICANCE STATEMENT Developing biomarkers of individuals at high risk for addiction before the onset of this brain-based disease is essential for prevention, early intervention, and/or subsequent treatment decisions. Using a rodent model of nicotine dependence and a novel data-driven, network-based analysis of resting-state fMRI data collected before drug exposure, functional connections centered on an intrinsic insular-frontal module predicted the severity of nicotine dependence after drug exposure. The predictive capacity of baseline network measures was specific to inter-regional but not within-region connectivity. While insular and frontal regions have consistently been implicated in nicotine dependence, this is the first study to reveal that innate, individual differences in their circuit strength have the predictive capacity to identify those at greatest risk for and resilience to drug dependence.
Asunto(s)
Corteza Cerebral/diagnóstico por imagen , Lóbulo Frontal/diagnóstico por imagen , Red Nerviosa/diagnóstico por imagen , Nicotina/administración & dosificación , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Tabaquismo/diagnóstico por imagen , Animales , Corteza Cerebral/efectos de los fármacos , Lóbulo Frontal/efectos de los fármacos , Neuroimagen Funcional , Pruebas Genéticas , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/efectos de los fármacos , Nicotina/efectos adversos , Ratas , Ratas Sprague-Dawley , Índice de Severidad de la EnfermedadRESUMEN
Cognitive dysfunction affects 40-80% of patients with multiple sclerosis. Smoking cannabis may add to these deficits. It is unclear whether coming off cannabis results in cognitive improvement. To address this question, 40 patients with multiple sclerosis who started using cannabis after the onset of multiple sclerosis and who used it for at least 4 days a week over many years were divided by odd-even number selection into two groups: cannabis continuation and cannabis withdrawal. Assessments took place at baseline and after 28 days and included serial versions of the Brief Repeatable Neuropsychological Battery for multiple sclerosis containing tests of verbal and visual memory, processing speed and executive function; structural and functional MRI, the latter entailing a compatible version of the Symbol Digit Modalities Test; urine for cannabinoid metabolites to detect compliance with abstinence. Only those participants deemed globally impaired at baseline (failure on at least two cognitive domains) were enrolled. The results revealed that the two groups were well matched demographically and neurologically. One subject was removed from the withdrawal group because of failed abstinence. Urine analysis revealed the cannabinoid consumed was predominantly tetrahydrocannabinol (THC). There were no baseline between group cognitive differences, but by Day 28 the withdrawal group performed significantly better on every cognitive index (P < 0.0001 for all). Significant within group differences were present for every test over time, but only in the abstinent group (P < 0.0001 for all tests). There were no between group baseline or Day 28 differences in structural MRI indices (global atrophy, total T1 and T2 lesion volume). At index assessment the two groups had a similar performance on the functional MRI-compatible Symbol Digit Modalities Test and there were no group differences in brain activation. However, by Day 28, the withdrawal group completed more trials correctly (P < 0.012) and had a faster reaction time (P < 0.002), associated with significantly increased activation in brain regions known to be associated with performance of the test (bilateral inferior frontal gyri, caudate and declive/cerebellum, P < 0.001 for all regions). These results reveal that patients with multiple sclerosis who are frequent, long-term cannabis users can show significant improvements in memory, processing speed and executive function after 28 days of drug abstinence. The absence of similar improvements in a matched multiple sclerosis group that remained on cannabis shows that beneficial cognitive change after stopping cannabis is not solely attributable to the effects of practice.
Asunto(s)
Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/psicología , Imagen por Resonancia Magnética/tendencias , Marihuana Medicinal/efectos adversos , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/psicología , Adulto , Cognición/efectos de los fármacos , Cognición/fisiología , Disfunción Cognitiva/inducido químicamente , Función Ejecutiva/efectos de los fármacos , Función Ejecutiva/fisiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Marihuana Medicinal/uso terapéutico , Pruebas de Estado Mental y Demencia , Persona de Mediana Edad , Esclerosis Múltiple/tratamiento farmacológico , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Síndrome de Abstinencia a Sustancias/psicología , Privación de Tratamiento/tendenciasRESUMEN
Many seizure-free patients who consider withdrawing from antiepileptic drugs (AEDs) hope to discontinue treatment to avoid adverse effects. However, withdrawal has certain risks that are difficult to predict. In this study, we performed a literature review, summarized the causes of significant variability in the risk of postwithdrawal recurrent seizures, and reviewed study data on the age at onset, cause, types of seizures, epilepsy syndrome, magnetic resonance imaging (MRI) abnormalities, epilepsy surgery, and withdrawal outcomes of patients with epilepsy. Many factors are associated with recurrent seizures after AED withdrawal. For patients who are seizure-free after treatment, the role of an electroencephalogram (EEG) alone in ensuring safe withdrawal is limited. A series of prediction models for the postwithdrawal recurrence risk have incorporated various potentially important factors in a comprehensive analysis. We focused on the populations of studies investigating five risk prediction models and analyzed the predictive variables and recommended applications of each model, aiming to provide a reference for personalized withdrawal for patients with epilepsy in clinical practice.
Asunto(s)
Anticonvulsivantes/uso terapéutico , Epilepsia/diagnóstico por imagen , Epilepsia/tratamiento farmacológico , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Electroencefalografía/tendencias , Epilepsia/fisiopatología , Humanos , Imagen por Resonancia Magnética/tendencias , Valor Predictivo de las Pruebas , Estudios Prospectivos , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Convulsiones/diagnóstico por imagen , Convulsiones/tratamiento farmacológico , Convulsiones/fisiopatología , Síndrome de Abstinencia a Sustancias/fisiopatologíaRESUMEN
BACKGROUND: Success of treatment withdrawal in patients with non-radiographic axial spondyloarthritis who are in remission remains unknown. The ABILITY-3 study explored the ability to withdraw adalimumab treatment in patients with non-radiographic axial spondyloarthritis who achieved sustained clinical remission after open-label treatment with adalimumab. METHODS: ABILITY-3 was a multicentre, two-period study done in 107 sites in 20 countries. We enrolled adult patients (≥18 years) diagnosed with non-radiographic axial spondyloarthritis, fulfilling Assessment of SpondyloArthritis international Society classification criteria but not the modified New York radiologic criterion, who had objective evidence of active inflammation, active disease, and inadequate response to at least two non-steroidal anti-inflammatory drugs. Patients who achieved Ankylosing Spondylitis Disease Activity Score (ASDAS) inactive disease (<1·3) with open-label adalimumab (40 mg subcutaneously every other week for 28 weeks) at weeks 16, 20, 24, and 28 were randomly assigned (1:1) using an interactive voice or web response system to 40-week, double-blind treatment with adalimumab (continuation) or placebo (withdrawal). The primary efficacy endpoint was the proportion of patients who did not experience a flare (defined as ASDAS ≥2·1 at two consecutive visits) during the double-blind period. Patients who flared were rescued with open-label adalimumab. This study is registered with ClinicalTrials.gov, number NCT01808118. FINDINGS: Between June 27, 2013, and October 22, 2015, 673 patients were enrolled to the study. The trial completed on April 14, 2017. Of 673 enrolled patients, 305 (45%) achieved sustained remission and were randomly assigned to double-blind treatment (152 patients to adalimumab and 153 to placebo). A greater proportion of patients continuing adalimumab than those receiving placebo did not experience a flare (107 [70%] of 152 patients vs 72 [47%] of 153 patients; p<0·0001) up to and including week 68. Among 673 patients receiving adalimumab at any time, 516 (77%) patients reported an adverse event and 28 (4%) experienced a serious adverse event. The most common adverse events in both the adalimumab and placebo groups were nasopharyngitis (25 [16%] vs 20 [13%]), upper respiratory tract infection (20 [13%] vs 12 [8%]), and worsening of axial spondyloarthritis (ten [7%] vs 21 [14%]). INTERPRETATION: In patients with active non-radiographic axial spondyloarthritis who achieved sustained remission with adalimumab, continued therapy was associated with significantly fewer patients flaring than was treatment withdrawal. FUNDING: AbbVie.
Asunto(s)
Adalimumab/administración & dosificación , Adalimumab/efectos adversos , Espondilitis Anquilosante/diagnóstico por imagen , Espondilitis Anquilosante/tratamiento farmacológico , Síndrome de Abstinencia a Sustancias/etiología , Adulto , Método Doble Ciego , Femenino , Humanos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Recurrencia , Síndrome de Abstinencia a Sustancias/diagnóstico por imagenRESUMEN
OBJECTIVE: Focal edema of the splenium of the corpus callosum (FESCC) is infrequently seen in patients with epilepsy who are undergoing video-electroencephalography (EEG) monitoring. It is diagnosed by qualitative visual inspection of the magnetic resonance imaging (MRI) and is usually assumed to be a dichotomous phenomenon. Rapid reduction of anticonvulsants has been proposed as a cause. In this study we investigate the relationship between dose reduction of anticonvulsants and the occurrence of FESCC, based on absolute drug doses. METHODS: We examined in detail the anticonvulsive therapy of all patients during video-EEG monitoring between 2014 and 2018. We compared patients with a radiologically diagnosed FESCC to controls in a 1:2 case-control analysis matched by age, epilepsy syndrome, and adjacent time of admission. In a separate correlation analysis, we examined quantitative effects of reduction of antiseizure drugs on diffusion restriction in the corpus callosum. RESULTS: Of 326 patients who had an MRI following video-EEG monitoring, 12 (3.7%) had FESCC. Antiseizure drugs were reduced to a significantly greater extent in FESCC patients than in the 24 controls (P < 0.001). Sodium channel-blocking antiseizure drugs were reduced (P < 0.001) and reintroduced (P < 0.001) significantly faster in FESCC patients, and the duration of anticonvulsant discontinuation was longer in FESCC patients (P < 0.001). The separate correlation analysis in 325 patients shows a weak correlation between diffusion restriction in the splenium and the reduction rate of sodium channel-blocking anticonvulsants (r = -0.15, P = 0.03) as well as the duration of their discontinuation (r = -0.16, P = 0.01). No such effects were found for anticonvulsants with other modes of action. SIGNIFICANCE: Our findings substantiate that FESCC is associated with high rates of dose reduction of anticonvulsants, specifically those acting on sodium channels. Our results cautiously suggest that reducing sodium-channel blockers has a small effect on diffusivity in the splenium below the visual threshold.
Asunto(s)
Anticonvulsivantes/efectos adversos , Edema Encefálico/inducido químicamente , Cuerpo Calloso , Bloqueadores de los Canales de Sodio/efectos adversos , Síndrome de Abstinencia a Sustancias/etiología , Adolescente , Adulto , Anciano , Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/uso terapéutico , Edema Encefálico/diagnóstico por imagen , Estudios de Casos y Controles , Niño , Preescolar , Cuerpo Calloso/diagnóstico por imagen , Cuerpo Calloso/patología , Electroencefalografía , Epilepsia/tratamiento farmacológico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Bloqueadores de los Canales de Sodio/administración & dosificación , Bloqueadores de los Canales de Sodio/uso terapéutico , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Adulto JovenRESUMEN
Smoking-induced relief of craving and withdrawal promotes continued cigarette use. Understanding how relief is produced and the role of nicotine in this process may facilitate development of new smoking-cessation therapies. As the US Food and Drug Administration considers setting a standard for reduced nicotine content in cigarettes to improve public health, knowledge of how nicotine contributes to relief also can inform policy. We assessed effects of nicotine using resting state functional magnetic resonance imaging (MRI) and behavioral assessments of craving and negative affect. Twenty-one young (18-25 years old) daily smokers underwent overnight abstinence on 4 days. On each of the following mornings, they self-rated their cigarette craving and negative affect and underwent resting-state functional MRI (fMRI) before and after smoking a cigarette that delivered 0.027, 0.110, 0.231, or 0.763 mg of nicotine. Functional connectivity between the anterior insula and anterior cingulate cortex (ACC) and between the nucleus accumbens and orbitofrontal cortex (OFC) was assessed. Smoking reduced craving, negative affect, and nucleus accumbens-OFC connectivity irrespective of nicotine dose, with positive correlations of the effects on behavioral and connectivity measures. Only the highest nicotine dose (0.763 mg) reduced right anterior insula-ACC connectivity; this reduction was positively correlated with the behavioral effects of the 0.763-mg dose only. While nicotine-based therapies may act on right anterior insula-ACC functional circuits to facilitate smoking cessation, non-nicotine (eg, the conditioned and sensorimotor) aspects of smoking may promote cessation by reducing OFC-accumbens connectivity to alleviate withdrawal.
Asunto(s)
Encéfalo/diagnóstico por imagen , Fumar Cigarrillos , Ansia/fisiología , Nicotina/administración & dosificación , Agonistas Nicotínicos/administración & dosificación , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Adolescente , Adulto , Afecto , Encéfalo/fisiopatología , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/fisiopatología , Relación Dosis-Respuesta a Droga , Femenino , Giro del Cíngulo/diagnóstico por imagen , Giro del Cíngulo/fisiopatología , Humanos , Imagen por Resonancia Magnética , Masculino , Nicotina/efectos adversos , Agonistas Nicotínicos/efectos adversos , Núcleo Accumbens/diagnóstico por imagen , Núcleo Accumbens/fisiopatología , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/fisiopatología , Síndrome de Abstinencia a Sustancias/etiología , Síndrome de Abstinencia a Sustancias/fisiopatología , Adulto JovenRESUMEN
Background: Although nicotine alters serotonergic neurochemistry, clinical trials of serotonergic medications for smoking cessation have provided mixed results. Understanding the role of serotonergic dysfunction in tobacco use disorder may advance development of novel pharmacotherapies. Methods: Functional magnetic resonance imaging was used to measure resting-state functional connectivity of the raphe nuclei as an indicator of serotonergic function. Connectivity of the dorsal and median raphe nuclei was compared between 18 young smokers (briefly abstinent, ~40 minutes post-smoking) and 19 young nonsmokers (16-21 years old); connectivity was also examined in a separate sample of overnight-abstinent smokers (18-25 years old), before and after smoking the first cigarette of the day. Relationships between connectivity of the raphe nuclei with psychological withdrawal and craving were tested in smokers. Results: Connectivity of the median raphe nucleus with the right hippocampal complex was weaker in smokers than in nonsmokers and was negatively correlated with psychological withdrawal in smokers. In overnight-abstinent smokers, smoking increased connectivity of the median raphe nucleus with the right hippocampal complex, and the increase was positively correlated with the decrease in psychological withdrawal. Conclusions: Relief of withdrawal due to smoking is potentially linked to the serotonergic pathway that includes the median raphe nucleus and hippocampal complex. These results suggest that serotonergic medications may be especially beneficial for smokers who endorse strong psychological withdrawal during abstinence from smoking.
Asunto(s)
Núcleos del Rafe/fisiopatología , Síndrome de Abstinencia a Sustancias/fisiopatología , Tabaquismo/fisiopatología , Adolescente , Mapeo Encefálico , Ansia/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/efectos de los fármacos , Vías Nerviosas/fisiopatología , Nicotina/administración & dosificación , Nicotina/efectos adversos , Agonistas Nicotínicos/administración & dosificación , Agonistas Nicotínicos/efectos adversos , Núcleos del Rafe/diagnóstico por imagen , Núcleos del Rafe/efectos de los fármacos , Descanso , Serotonina/metabolismo , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Síndrome de Abstinencia a Sustancias/psicología , Factores de Tiempo , Tabaquismo/diagnóstico por imagen , Tabaquismo/psicología , Adulto JovenRESUMEN
Background: Identifying the biological basis of smoking cessation success is of growing interest. The rate of nicotine metabolism, measured by the nicotine metabolite ratio, affects multiple aspects of nicotine dependence. Fast nicotine metabolizers tend to smoke more, experience more withdrawal and craving, and have lower cessation rates compared with slow metabolizers. The nicotine metabolite ratio predicts treatment response, and differences in brain activation between fast metabolizers and slow metabolizers have been reported in fMRI studies. As reinforcing/rewarding effects of tobacco are associated with dopamine transmission, the purpose of the present study was to study the dopaminergic system in human smokers based on their nicotine metabolite ratio. Methods: The first aim of the study was to explore if there were differences in D2 and D3 receptor binding between fast metabolizers and slow metabolizers during abstinence. The second aim was to explore smoking-induced dopamine release in both groups. Participants underwent 2 [11C]-(+)-PHNO PET scans: one scan during abstinence and the other after smoking a tobacco cigarette. Subjective measures were recorded and blood was drawn for measurement of nicotine and cotinine levels. Results: During abstinence, slow metabolizers (n = 13) had lower [11C]-(+)-PHNO binding potential than fast metabolizers (n = 15) restricted to the D2 regions of the associative striatum and sensorimotor striatum. After smoking a cigarette, [11C]-(+)-PHNO binding potential was decreased in the limbic striatum and ventral pallidum, suggestive of increases in dopamine, but there were no nicotine metabolite ratio differences. Conclusions: Further studies are required to delineate if differences in [11C]-(+)-PHNO binding between slow metabolizers and fast metabolizers at abstinence baseline are preexisting traits or induced by prolonged tobacco use.
Asunto(s)
Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Nicotina/metabolismo , Oxazinas/metabolismo , Tabaquismo/diagnóstico por imagen , Tabaquismo/metabolismo , Adulto , Isótopos de Carbono , Cotinina/metabolismo , Femenino , Humanos , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Masculino , Nicotina/administración & dosificación , Agonistas Nicotínicos/administración & dosificación , Agonistas Nicotínicos/metabolismo , Tomografía de Emisión de Positrones , Radiofármacos , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D3/metabolismo , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Síndrome de Abstinencia a Sustancias/metabolismo , Fumar Tabaco/metabolismoRESUMEN
BACKGROUND: Alcohol dependence and tobacco smoking are highly comorbid, and treating both conditions simultaneously is controversial. Previously, we showed that tobacco smoking interferes with GABAA receptor neuroadaptations during alcohol withdrawal in humans, while this effect did not occur with continued nicotine use during alcohol abstinence in nonhuman primates. Here, we extend our previous work by measuring GABAA receptor availability with positron emission tomography (PET) during drug abstinence in nonhuman primates exposed to alcohol alone, nicotine and alcohol together, and alcohol abstinence with continued nicotine exposure. METHODS: Twenty-four adolescent male rhesus macaques orally self-administered alcohol and nicotine, available separately in water and saccharin, over 20 weeks. The groups included alcohol alone (n = 8); nicotine and alcohol with simultaneous abstinence (n = 8); nicotine and alcohol with alcohol abstinence while nicotine was still available (n = 8); and a pilot group of animals consuming nicotine alone (n = 6). Animals were imaged with [(11)C]flumazenil PET to measure binding potential (BPND), an index of GABAA receptor availability. Imaging occurred at baseline (drug-naíve), and following alcohol and/or nicotine cessation at 1 day, 8 days, and 12 weeks of abstinence. Generalized linear mixed models were used to examine the time course of [(11)C]flumazenil BPND during alcohol abstinence across groups. RESULTS: Animals consumed 3.95 ± 1.22 g/kg/d alcohol and 55.4 ± 35.1 mg/kg/d nicotine. No significant group effects were observed in [(11)C]flumazenil BPND during alcohol abstinence; however, a main effect of time was detected. Post hoc analyses indicated that all groups abstaining from alcohol exhibited significantly increased GABAA receptor availability at 1 day and 8 days (but not 12 weeks) of abstinence relative to baseline, while no changes in [(11)C]flumazenil BPND during nicotine abstinence alone were observed. CONCLUSIONS: These data indicate that neither nicotine nor nicotine abstinence interferes with GABAA receptor neuroadaptations during alcohol withdrawal. This conclusion is consistent with our previous study and does not contradict the use of nicotine replacement therapies or non-nicotinic-acting pharmaceuticals to quit smoking during alcohol withdrawal from a GABAergic perspective.
Asunto(s)
Abstinencia de Alcohol , Alcoholismo/metabolismo , Etanol/metabolismo , Nicotina/metabolismo , Receptores de GABA-A/metabolismo , Síndrome de Abstinencia a Sustancias/metabolismo , Adaptación Fisiológica/fisiología , Alcoholismo/diagnóstico por imagen , Animales , Etanol/administración & dosificación , Macaca mulatta , Masculino , Nicotina/administración & dosificación , Tomografía de Emisión de Positrones , Autoadministración , Síndrome de Abstinencia a Sustancias/diagnóstico por imagenRESUMEN
OBJECTIVE: To investigate alterations of resting brain function in codeine-containing cough syrups (CCS) dependent individuals before and after ultra-rapid opioid detoxification under general anaesthesia (UROD) combined with naltrexone treatment (NMT). METHODS: Fourteen CCS-dependent individuals were scanned using resting-state fMRI. After UROD and 2 weeks of NMT, CCS-dependent individuals were rescanned. Fourteen matched controls were studied at baseline and compared. The amplitude of low frequency fluctuations (ALFF) and seed-based functional connectivity (FC) were used to characterize resting-state cerebral function. RESULTS: After UROD and 2 weeks of NMT, CCS-dependent individuals had increased ALFF in the bilateral parahippocampal gyrus and right medial orbitofrontal cortex (mOFC), decreased ALFF in the left post-central gyrus (PoCG), left middle occipital cortex (MOC) and left dorsal lateral prefrontal cortex (DLPFC), and reduced FC between right mOFC and right DLPFC, and between left DLPFC and left inferior parietal lobe relative to pretreatment. Decreased ALFFs in the left PoCG and left MOC were associated with decreased withdrawal syndrome severity in CCS-dependent individuals. CONCLUSIONS: We offer the first report describing how regional and integral synchronous neural activity occurs after UROD and short-term NMT, accompanied by decreased withdrawal syndrome severity. These findings contribute to the understanding of complex systems involved in UROD-NMT effects. KEY POINTS: ⢠CCS-dependent individuals had reduced ALFF and increased FC at baseline. ⢠UROD treatment can change the regional and integral brain function of CCS-dependent individuals. ⢠Attenuated ALFFs are correlated with the withdrawal syndrome after treatment.
Asunto(s)
Anestesia General , Encéfalo/efectos de los fármacos , Codeína/envenenamiento , Naltrexona/uso terapéutico , Tratamiento de Sustitución de Opiáceos/métodos , Trastornos Relacionados con Opioides/rehabilitación , Adulto , Antitusígenos/envenenamiento , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Mapeo Encefálico/métodos , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Antagonistas de Narcóticos/uso terapéutico , Estudios Prospectivos , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Síndrome de Abstinencia a Sustancias/fisiopatología , Resultado del Tratamiento , Adulto JovenAsunto(s)
Imagen de Perfusión Miocárdica , Omeprazol/administración & dosificación , Estómago/efectos de los fármacos , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/efectos de los fármacos , Humanos , Persona de Mediana Edad , Inhibidores de la Bomba de Protones/administración & dosificación , Tecnecio Tc 99m SestamibiRESUMEN
We previously reported that people with multiple sclerosis (pwMS) who have been using cannabis frequently over many years can have significant cognitive improvements accompanied by concomitant task-specific changes in brain activation following 28 days of cannabis abstinence. We now hypothesize that the default Mode Network (DMN), known to modulate cognition, would also show an improved pattern of activation align with cognitive improvement following 28 days of drug abstinence. Thirty three cognitively impaired pwMS who were frequent cannabis users underwent a neuropsychological assessment and fMRI at baseline. Individuals were then assigned to a cannabis continuation (CC, n = 15) or withdrawal (CW, n = 18) group and the cognitive and imaging assessments were repeated after 28 days. Compliance with cannabis withdrawal was checked with regular urine monitoring. Following acquisition of resting state fMRI (rs-fMRI), data were processed using independent component analysis (ICA) to identify the DMN spatial map. Between and within group analyses were carried out using dual regression for voxel-wise comparisons of the DMN. Clusters of voxels were considered statistically significant if they survived threshold-free cluster enhancement (TFCE) correction at p < 0.05. The two groups were well matched demographically and neurologically at baseline. The dual regression analysis revealed no between group differences at baseline in the DMN. By day 28, the CW group in comparison to the CC group had increased activation in the left posterior cingulate, and right, angular gyrus (p < 0.05 for both, TFCE). A within group analysis for the CC group revealed no changes in resting state (RS) networks. Within group analysis of the CW group revealed increased activation at day 28 versus baseline in the left posterior cingulate, right angular gyrus, left hippocampus (BA 36), and the right medial prefrontal cortex (p < 0.05). The CW group showed significant improvements in multiple cognitive domains. In summary, our study revealed that abstaining from cannabis for 28 days reverses activation of DMN activity in pwMS in association with improved cognition across several domains.
Asunto(s)
Imagen por Resonancia Magnética , Esclerosis Múltiple , Humanos , Masculino , Femenino , Imagen por Resonancia Magnética/métodos , Adulto , Esclerosis Múltiple/fisiopatología , Esclerosis Múltiple/diagnóstico por imagen , Persona de Mediana Edad , Cognición/fisiología , Encéfalo/fisiopatología , Encéfalo/diagnóstico por imagen , Encéfalo/efectos de los fármacos , Red en Modo Predeterminado/fisiopatología , Red en Modo Predeterminado/diagnóstico por imagen , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiopatología , Síndrome de Abstinencia a Sustancias/fisiopatología , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Disfunción Cognitiva/fisiopatología , Disfunción Cognitiva/etiología , Disfunción Cognitiva/diagnóstico por imagen , Descanso/fisiologíaRESUMEN
Sex differences exist in tobacco smoking behaviors. Nicotine, the primary addictive ingredient in tobacco smoke, indirectly affects γ-amino butyric acid (GABA) function. Previous studies reported sex-by-smoking interactions in brain GABA levels. The goal of the present study was to evaluate if there is a sex-by-smoking interaction at the GABA(A)-benzodiazepine receptors (GABA(A)-BZRs), as well as relationships between GABA(A)-BZR availability and behavioral variables before and after 1 week of smoking cessation. Twenty-six women (8 non-smokers, age 36.0 ± 13.4 years; 19 smokers, age 34.6 ± 8.9 years) and 25 men (8 non-smokers, age 37.9 ± 13.8 years; 17 smokers, 34.1 ± 12.4 years) were imaged using [123I]iomazenil and single-photon emission computed tomography. Smokers were imaged at baseline 7 hours after the last cigarette. A significantly great number of men were able to abstain from smoking for 1 week (P = 0.003). There were no significant differences in nicotine dependence and cigarette craving, mood or pain sensitivity between male and female smokers. There was a significant effect of gender across all brain regions (frontal, parietal, anterior cingulate, temporal and occipital cortices, and cerebellum; P < 0.05), with all women (smokers and non-smokers combined) having a higher GABA(A)-BZR availability than all men. There was a negative correlation between GABA(A)-BZR availability and craving (P ≤ 0.02) and pain sensitivity (P = 0.04) in female smokers but not male smokers. This study provides further evidence of a sex-specific regulation of GABA(A)-BZR availability in humans and demonstrates the potential for GABA(A)-BZRs to mediate tobacco smoking craving and pain symptoms differentially in female and male smokers.
Asunto(s)
Percepción del Dolor/fisiología , Receptores de GABA-A/metabolismo , Caracteres Sexuales , Síndrome de Abstinencia a Sustancias/metabolismo , Tabaquismo/metabolismo , Adulto , Síntomas Afectivos/psicología , Análisis de Varianza , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Femenino , Flumazenil/análogos & derivados , Moduladores del GABA , Humanos , Masculino , Persona de Mediana Edad , Nicotina/farmacología , Percepción del Dolor/efectos de los fármacos , Receptores de GABA-A/efectos de los fármacos , Cese del Hábito de Fumar , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Síndrome de Abstinencia a Sustancias/fisiopatología , Tabaquismo/diagnóstico por imagen , Tabaquismo/fisiopatología , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adulto JovenRESUMEN
This study evaluates the long-term effects of a six and 14-week morphine withdrawal in rats pretreated with a cannabinoid agonist (CP-55,940, CP) during periadolescence. Wistar rats (33 males; 32 females) were treated with CP or its vehicle (VH) from postnatal day (PND) 28-38. At PND100, rats performed morphine self-administration (MSA, 15d/12 h/session). Eight groups were defined according to pretreatment (CP), treatment (morphine), and sex. Three [18F]FDG-PET brain images were acquired: after MSA, and after six and 14 weeks of withdrawal. PET data were analyzed with SPM12. Endocannabinoid (EC) markers were evaluated in frozen brain tissue at endpoint. Females showed a higher mean number of self-injections than males. A main Sex effect on global brain metabolism was found. FDG uptake in males was discrete, whereas females showed greater brain metabolism changes mainly in areas of the limbic system after morphine treatment. Moreover, the morphine-induced metabolic pattern in females was exacerbated when CP was previously present. In addition, the CP-Saline male group showed reduced CB1R, MAGL expression, and NAPE/FAAH ratio compared to the control group, and morphine was able to reverse CB1R and MAGL expression almost to control levels. In conclusion, females showed greater and longer-lasting metabolic changes after morphine withdrawal than males, indicating a higher vulnerability and a different sensitivity to morphine in subjects pre-exposed to CP. In contrast, males primarily showed changes in EC markers. Together, our results suggest that CP pre-exposure contributes to the modulation of brain metabolism and EC systems in a sex-dependent manner.
Asunto(s)
Morfina , Síndrome de Abstinencia a Sustancias , Femenino , Ratas , Animales , Masculino , Morfina/farmacología , Agonistas de Receptores de Cannabinoides/farmacología , Ratas Wistar , Fluorodesoxiglucosa F18 , Endocannabinoides , Neuroimagen , Glucosa , Síndrome de Abstinencia a Sustancias/diagnóstico por imagenRESUMEN
INTRODUCTION: Cerebral Venous Sinus Thrombosis (CVST) remains a challenge to diagnose due to its rarity and nonspecific symptomatology. We have found alcohol withdrawal can display symptoms similar to CVST. We present a unique case of intraparenchymal hemorrhage secondary to an extensive CVST in a patient presenting with symptoms suggestive of alcohol withdrawal. CASE REPORT: A 33-year-old woman with a history of alcohol dependence presented with a worsening headache and right upper dental pain. She denied any trauma and attributed the headache to alcohol withdrawal. She denied consuming alcohol in the last 24 hours but reported a daily intake of 20 oz of whiskey. Physical examination noted dental caries and a normal neurological examination. Laboratory values indicated leukocytosis with neutrophilia and microcytic anemia. Computed tomography brain without contrast was conducted to rule out head trauma, revealing a 1.2 cm intraparenchymal hemorrhage in the left frontal lobe with local edema. Neurosurgery recommended a computed tomography angiography, which demonstrated contrast filling defects consistent with CVST (confirmed by magnetic resonance venography). The patient was admitted to the intensive care unit; during her hospital course, further testing revealed heterozygous methylenetetrahydrofolate reductase mutation and elevated homocysteine levels. Patient underwent acute treatment with enoxaparin bridged to apixaban. Patient was discharged on day 7 neurologically intact with the improvement of all symptoms. CONCLUSION: This unique presentation of CVST alongside alcohol withdrawal symptoms highlights the importance of recognizing atypical presentations of CVST in higher-risk patient populations. A heightened index of suspicion for the wide range of presentations of CVST is necessary to assess, diagnose, and treat at-risk patients.