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The brain is the seat of body weight homeostasis. However, our inability to control the increasing prevalence of obesity highlights a need to look beyond canonical feeding pathways to broaden our understanding of body weight control1-3. Here we used a reverse-translational approach to identify and anatomically, molecularly and functionally characterize a neural ensemble that promotes satiation. Unbiased, task-based functional magnetic resonance imaging revealed marked differences in cerebellar responses to food in people with a genetic disorder characterized by insatiable appetite. Transcriptomic analyses in mice revealed molecularly and topographically -distinct neurons in the anterior deep cerebellar nuclei (aDCN) that are activated by feeding or nutrient infusion in the gut. Selective activation of aDCN neurons substantially decreased food intake by reducing meal size without compensatory changes to metabolic rate. We found that aDCN activity terminates food intake by increasing striatal dopamine levels and attenuating the phasic dopamine response to subsequent food consumption. Our study defines a conserved satiation centre that may represent a novel therapeutic target for the management of excessive eating, and underscores the utility of a 'bedside-to-bench' approach for the identification of neural circuits that influence behaviour.
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Mantenimiento del Peso Corporal/genética , Mantenimiento del Peso Corporal/fisiología , Cerebelo/fisiología , Alimentos , Biosíntesis de Proteínas , Genética Inversa , Respuesta de Saciedad/fisiología , Adulto , Animales , Regulación del Apetito/genética , Regulación del Apetito/fisiología , Núcleos Cerebelosos/citología , Núcleos Cerebelosos/fisiología , Cerebelo/citología , Señales (Psicología) , Dopamina/metabolismo , Ingestión de Alimentos/genética , Ingestión de Alimentos/fisiología , Conducta Alimentaria/fisiología , Femenino , Homeostasis , Humanos , Imagen por Resonancia Magnética , Masculino , Ratones , Ratones Endogámicos C57BL , Neostriado/metabolismo , Neuronas/fisiología , Obesidad/genética , Filosofía , Adulto JovenRESUMEN
OBJECTIVE: Few studies have focused on brain structure in atypical anorexia nervosa (atypical AN). This study investigates differences in gray matter volume (GMV) between females with anorexia nervosa (AN) and atypical AN, and healthy controls (HC). METHOD: Structural magnetic resonance imaging data were acquired for 37 AN, 23 atypical AN, and 41 HC female participants. Freesurfer was used to extract GMV, cortical thickness, and surface area for six brain lobes and associated cortical regions of interest (ROI). Primary analyses employed linear mixed-effects models to compare group differences in lobar GMV, followed by secondary analyses on ROIs within significant lobes. We also explored relationships between cortical gray matter and both body mass index (BMI) and symptom severity. RESULTS: Our primary analyses revealed significant lower GMV in frontal, temporal and parietal areas (FDR < .05) in AN and atypical AN when compared to HC. Lobar GMV comparisons were non-significant between atypical AN and AN. The parietal lobe exhibited the greatest proportion of affected cortical ROIs in both AN versus HC and atypical AN versus HC. BMI, but not symptom severity, was found to be associated with cortical GMV in the parietal, frontal, temporal, and cingulate lobes. No significant differences were observed in cortical thickness or surface area. DISCUSSION: We observed lower GMV in frontal, temporal, and parietal areas, when compared to HC, but no differences between AN and atypical AN. This indicates potentially overlapping structural phenotypes between these disorders and evidence of brain changes among those who are not below the clinical underweight threshold. PUBLIC SIGNIFICANCE: Despite individuals with atypical anorexia nervosa presenting above the clinical weight threshold, lower cortical gray matter volume was observed in partial, temporal, and frontal cortices, compared to healthy individuals. No significant differences were found in cortical gray matter volume between anorexia nervosa and atypical anorexia nervosa. This underscores the importance of continuing to assess and target weight gain in clinical care, even for those who are presenting above the low-weight clinical criteria.
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Anorexia Nerviosa , Sustancia Gris , Humanos , Femenino , Sustancia Gris/diagnóstico por imagen , Anorexia Nerviosa/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Mapeo Encefálico , DelgadezRESUMEN
BACKGROUND: Major depressive disorder (MDD) is often accompanied by changes in appetite and weight. Prior task-based functional magnetic resonance imaging (fMRI) findings suggest these MDD phenotypes are associated with altered reward and interoceptive processing. METHODS: Using resting-state fMRI data, we compared the fractional amplitude of low-frequency fluctuations (fALFF) and seed-based connectivity (SBC) among hyperphagic (n = 77), hypophagic (n = 66), and euphagic (n = 42) MDD groups and a healthy comparison group (n = 38). We examined fALFF and SBC in a mask restricted to reward [nucleus accumbens (NAcc), putamen, caudate, ventral pallidum, and orbitofrontal cortex (OFC)] and interoceptive (anterior insula and hypothalamus) regions and also performed exploratory whole-brain analyses. SBC analyses included as seeds the NAcc and also regions demonstrating group differences in fALFF (i.e. right lateral OFC and right anterior insula). All analyses used threshold-free cluster enhancement. RESULTS: Mask-restricted analyses revealed stronger fALFF in the right lateral OFC, and weaker fALFF in the right anterior insula, for hyperphagic MDD v. healthy comparison. We also found weaker SBC between the right lateral OFC and left anterior insula for hyperphagic MDD v. healthy comparison. Whole-brain analyses revealed weaker fALFF in the right anterior insula, and stronger SBC between the right lateral OFC and left precentral gyrus, for hyperphagic MDD v. healthy comparison. Findings were no longer significant after controlling for body mass index, which was higher for hyperphagic MDD. CONCLUSIONS: Our results suggest hyperphagic MDD may be associated with altered activity in and connectivity between interoceptive and reward regions.
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Trastorno Depresivo Mayor , Humanos , Trastorno Depresivo Mayor/diagnóstico por imagen , Apetito , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos , FenotipoRESUMEN
OBJECTIVE: The amygdaloid complex plays a pivotal role in emotion processing and has been associated with rumination transdiagnostically. In anorexia nervosa (AN), we previously observed differential reductions of amygdala nuclei volumes (rostral-medial cluster substantially affected) and, in another study, elevated food-/weight-related rumination. Both amygdala volumes and rumination frequency correlated with characteristically suppressed leptin levels in AN. Thus, we hypothesized that amygdala nuclei alterations might be associated with AN-related rumination and potentially mediate the leptin-rumination relationship in AN. METHODS: Rumination (food-/weight-related) was assessed using ecological momentary assessment for a 14-day period. We employed frequentist and Bayesian linear mixed effects models in females with AN (n = 51, 12-29 years, majority admitted to inpatient treatment) and age-matched healthy females (n = 51) to investigate associations between rostral-medial amygdala nuclei volume alterations (accessory basal, cortical, medial nuclei, corticoamygdaloid transitions) and rumination. We analyzed mediation effects using multi-level structural equation models. RESULTS: Reduced right accessory basal and cortical nuclei volumes predicted more frequent weight-related rumination in AN; both nuclei fully mediated the effect of leptin on weight-related rumination. In contrast, we found robust evidence for the absence of amygdala nuclei volume effects on rumination in healthy females. CONCLUSION: This study provides first evidence for the relevance of specific amygdala substructure reductions regarding cognitive symptom severity in AN and points toward novel mechanistic insight into the relationship between hypoleptinemia and rumination, which might involve the amygdaloid complex. Our findings in AN may have important clinical value with respect to understanding the beneficial neuropsychiatric effects of leptin (treatment) in AN and potentially other psychiatric conditions such as depression.
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Anorexia Nerviosa , Femenino , Humanos , Leptina , Teorema de Bayes , Amígdala del Cerebelo/diagnóstico por imagen , Evaluación Ecológica MomentáneaRESUMEN
BACKGROUND: Emotional eating has emerged as a contributing factor to overeating, potentially leading to obesity or disordered eating behaviors. However, the underlying biological mechanisms related to emotional eating remain unclear. The present study examined emotional, hormonal, and neural alterations elicited by an acute laboratory stressor in individuals with and without emotional eating. METHODS: Emotional (n = 13) and non-emotional eaters (n = 15) completed two main study visits, one week apart: one visit included a Stress version and the other a No-stress version of the Maastricht Acute Stress Task (MAST). Immediately pre- and post-MAST, blood was drawn for serum cortisol and participants rated their anxiety level. After the MAST, participants completed a Food Incentive Delay (FID) task during functional magnetic resonance imaging (fMRI), followed by an ad libitum snack period. RESULTS: Emotional eaters exhibited elevated anxiety (p = 0.037) and cortisol (p = 0.001) in response to the Stress MAST. There were no changes in anxiety or cortisol among non-emotional eaters in response to the Stress MAST or in either group in response to the No-stress MAST. In response to the Stress MAST, emotional eaters exhibited reduced activation during anticipation of food reward in mesolimbic reward regions (caudate: p = 0.014, nucleus accumbens: p = 0.022, putamen: p = 0.013), compared to non-emotional eaters. Groups did not differ in snack consumption. CONCLUSIONS: These data indicate disrupted neuroendocrine and neural responsivity to psychosocial stress amongst otherwise-healthy emotional eaters, who demonstrated hyperactive HPA-axis response coupled with hypoactivation in reward circuitry. Differential responsivity to stress may represent a risk factor in the development of maladaptive eating behaviors.
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Conducta Alimentaria , Estrés Psicológico , Ingestión de Alimentos , Emociones , Humanos , Hidrocortisona , Imagen por Resonancia Magnética , RecompensaRESUMEN
PURPOSE: Gamma-aminobutyric acid (GABA) abnormalities have been implicated in a range of neuropsychiatric disorders. Despite substantial interest in probing GABA in vivo, human imaging studies relying on magnetic resonance spectroscopy (MRS) have generally been hindered by technical challenges, including GABA's relatively low concentration and spectral overlap with other metabolites. Although past studies have shown moderate-to-strong test-retest repeatability and reliability of GABA within certain brain regions, many of these studies have been limited by small sample sizes. METHODS: GABA+ (macromolecular-contaminated) test-retest reliability and repeatability were assessed via a Meshcher-Garwood point resolved spectroscopy (MEGA-PRESS) MRS sequence in the rostral anterior cingulate cortex (rACC; n = 21) and dorsolateral prefrontal cortex (dlPFC; n = 20) in healthy young adults. Data were collected on a 3T scanner (Siemens Prisma, Siemens Healthcare, Erlangen, Germany) and GABA+ results were reported in reference to both total creatine (GABA+/tCr) and water (GABA+/water). RESULTS: Results showed strong test-retest repeatability (mean GABA+/tCr coefficient of variation [CV] = 4.6%; mean GABA+/water CV = 4.0%) and reliability (GABA+/tCr intraclass correlation coefficient [ICC] = 0.77; GABA+/water ICC = 0.87) in the dlPFC. The rACC showed acceptable (but comparatively lower) repeatability (mean GABA+/tCr CV = 8.0%; mean GABA+/water CV = 7.5%), yet low-moderate reliability (GABA+/tCr ICC = 0.40; GABA+/water ICC = 0.44). CONCLUSION: The present study found excellent GABA+ MRS repeatability and reliability in the dlPFC. The rACC showed inferior results, possibly because of a combination of shimming impedance and measurement error. These data suggest that MEGA-PRESS can be utilized to reliably distinguish participants based on dlPFC GABA+ levels, whereas the mixed results in the rACC merit further investigation.
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Imagen por Resonancia Magnética , Ácido gamma-Aminobutírico , Alemania , Humanos , Espectroscopía de Resonancia Magnética , Reproducibilidad de los Resultados , Adulto JovenRESUMEN
BACKGROUND: Obesity has one of the highest refractory rates of all chronic diseases, in part because weight loss induced by calorie restriction, the first-line treatment for obesity, elicits biological adaptations that promote weight regain. Although acute feeding trials suggest a role for macronutrient composition in modifying brain activity related to hunger and satiety, relevance of these findings to weight-loss maintenance has not been studied. OBJECTIVES: We investigated effects of weight-loss maintenance diets varying in macronutrient content on regional cerebral blood flow (rCBF) in brain regions involved in hunger and reward. METHODS: In conjunction with a randomized controlled feeding trial, we investigated the effects of weight-loss maintenance diets varying in carbohydrate content [high, 60% of total energy: n = 20; 6 men/14 women; mean age: 32.5 y; mean BMI (in kg/m 2): 27.4; moderate, 40% of total energy: n = 22; 10 men/12 women; mean age: 32.5 y; mean BMI: 29.0; low, 20% of total energy: n = 28; 12 men/16 women; mean age: 33.2 y; mean BMI: 27.7] on rCBF in brain regions involved in hunger and reward preprandial and 4 h postprandial after 14-20 wk on the diets. The primary outcome was rCBF in the nucleus accumbens (NAcc) at 4 h postprandial; the secondary outcome was preprandial rCBF in the hypothalamus. RESULTS: Consistent with a priori hypothesis, at 4 h postprandial, NAcc rCBF was 43% higher in adults assigned to the high- compared with low-carbohydrate diet {P[family-wise error (FWE)-corrected] < 0.05}. Preprandial hypothalamus rCBF was 41% higher on high-carbohydrate diet [P(FWE-corrected) < 0.001]. Exploratory analyses revealed that elevated rCBF on high-carbohydrate diet was not specific to prandial state: preprandial NAcc rCBF [P(FWE-corrected) < 0.001] and 4 h postprandial rCBF in hypothalamus [P(FWE-corrected) < 0.001]. Insulin secretion predicted differential postprandial activation of the NAcc by diet. CONCLUSIONS: We report significant differences in rCBF in adults assigned to diets varying in carbohydrate content for several months, which appear to be partially associated with insulin secretion. These findings suggest that chronic intake of a high-carbohydrate diet may affect brain reward and homeostatic activity in ways that could impede weight-loss maintenance. This trial was registered at clinicaltrials.gov as NCT02300857.
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Dieta Baja en Carbohidratos , Pérdida de Peso , Adulto , Carbohidratos de la Dieta , Ingestión de Energía , Femenino , Humanos , Hipotálamo , Masculino , RecompensaRESUMEN
Negative affective stimuli elicit behavioral and neural responses which vary on a continuum from adaptive to maladaptive, yet are typically investigated in a dichotomous manner (healthy controls vs. psychiatric diagnoses). This practice may limit our ability to fully capture variance from acute responses to negative affective stimuli to psychopathology at the extreme end. To address this, we conducted a functional magnetic resonance imaging study to examine the neural responses to negative valence/high arousal and neutral valence/low arousal images as a function of dysphoric mood and sex across individuals (n = 99) who represented traditional categories of healthy controls, major depressive disorder, bipolar psychosis, and schizophrenia. Observation of negative (vs. neutral) stimuli elicited blood oxygen-level dependent responses in the following circuitry: periaqueductal gray, hypothalamus (HYPO), amygdala (AMYG), hippocampus (HIPP), orbitofrontal cortex (OFC), medial prefrontal cortex (mPFC), and greater connectivity between AMYG and mPFC. Across all subjects, severity of dysphoric mood was associated with hyperactivity of HYPO, and, among females, right (R) AMYG. Females also demonstrated inverse relationships between severity of dysphoric mood and connectivity between HYPO - R OFC, R AMYG - R OFC, and R AMYG - R HIPP. Overall, our findings demonstrated sex-dependent deficits in response to negative affective stimuli increasing as a function of dysphoric mood state. Females demonstrated greater inability to regulate arousal as mood became more dysphoric. These findings contribute to elucidating biosignatures associated with response to negative stimuli across disorders and suggest the importance of a sex-dependent lens in determining these biosignatures. Hum Brain Mapp 37:3733-3744, 2016. © 2016 Wiley Periodicals, Inc.
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Afecto/fisiología , Trastorno Bipolar/fisiopatología , Encéfalo/fisiopatología , Trastorno Depresivo Mayor/fisiopatología , Esquizofrenia/fisiopatología , Caracteres Sexuales , Adulto , Ansiedad/diagnóstico por imagen , Ansiedad/fisiopatología , Trastorno Bipolar/diagnóstico por imagen , Trastorno Bipolar/psicología , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Circulación Cerebrovascular/fisiología , Trastorno Depresivo Mayor/diagnóstico por imagen , Trastorno Depresivo Mayor/psicología , Análisis Factorial , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiopatología , Oxígeno/sangre , Trastornos Psicóticos/diagnóstico por imagen , Trastornos Psicóticos/fisiopatología , Trastornos Psicóticos/psicología , Esquizofrenia/diagnóstico por imagen , Psicología del EsquizofrénicoRESUMEN
ABSTRACT: Substance use disorder (SUD) continues to be a leading cause of morbidity and mortality with limited treatments. There is interest in expanding the use of GLP-1 agonists in treating SUD. However, evidence for safety and efficacy in humans is limited. This review aims to bridge the existing knowledge gap by establishing a baseline of literature in this area to inform future trials and clinical practice. Our inclusion criteria were English peer-reviewed manuscripts reporting on use of GLP-1, GIP, and/or glucagon receptor agonists in treatment of SUDs, excluding case studies. The literature search was performed in accordance to PRISMA guidelines. Five studies were included in this review examining the use of this medication in tobacco use disorder, alcohol use disorder, and cocaine use disorder. No studies regarding substance withdrawal syndrome were identified. The included studies varied widely in terms of patient selection, dose/formulation of GLP-1 agonists, and follow-up. The results of this scoping review are mixed, with 3 studies demonstrating positive results and 2 studies finding no efficacy of this medication on SUD outcomes. It is premature to prescribe this medication off-label to patients. Further research is needed to determine the efficacy of GLP-1 agonists in treating SUD.
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BACKGROUND: Neurocognitive factors including aberrant reward learning, blunted GABA (gamma-aminobutyric acid), and potentiated stress sensitivity have been linked to anhedonia, a hallmark depressive symptom, possibly in a sex-dependent manner. However, previous research has not investigated the putative associations among these factors or the extent to which they represent trait- or state-based vulnerabilities for depression. METHODS: Young adults with current major depressive disorder (MDD) (n = 44), remitted MDD (n = 42), and healthy control participants (HCs) (n = 44), stratified by sex assigned at birth, underwent magnetic resonance spectroscopy to assess macromolecular contaminated GABA (GABA+) and then a reward learning task before and after acute stress. We assessed changes in reward learning after stress and associations with GABA+. RESULTS: Results revealed blunted baseline reward learning in participants with remitted MDD versus participants with current MDD and HCs but, surprisingly, no differences between participants with current MDD and HCs. Reward learning was reduced following acute stress regardless of depressive history. GABA+ in the rostral anterior cingulate cortex, but not the dorsolateral prefrontal cortex, was associated with reduced baseline reward learning only in female participants. GABA+ did not predict stress-related changes in reward learning. CONCLUSIONS: To our knowledge, this is the first study to investigate associations among GABA, reward learning, and stress reactivity in current versus past depression. Hypothesized depression-related differences in reward learning did not emerge, precluding claims about state versus trait vulnerabilities. However, our finding that blunted GABA was associated with greater reward learning in female participants provides novel insights into sex-selective associations between the frontal GABAergic inhibitory system and reward processing.
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Trastorno Depresivo Mayor , Recompensa , Estrés Psicológico , Ácido gamma-Aminobutírico , Humanos , Femenino , Masculino , Trastorno Depresivo Mayor/fisiopatología , Trastorno Depresivo Mayor/metabolismo , Adulto Joven , Ácido gamma-Aminobutírico/metabolismo , Estrés Psicológico/metabolismo , Estrés Psicológico/fisiopatología , Adulto , Aprendizaje/fisiología , Giro del Cíngulo/metabolismo , Giro del Cíngulo/fisiopatología , Giro del Cíngulo/diagnóstico por imagen , Espectroscopía de Resonancia Magnética , Caracteres Sexuales , Factores Sexuales , AdolescenteRESUMEN
BACKGROUND: Understanding the neurobiological effects of stress is critical for addressing the etiology of major depressive disorder (MDD). Using a dimensional approach involving individuals with differing degree of MDD risk, we investigated 1) the effects of acute stress on cortico-cortical and subcortical-cortical functional connectivity (FC) and 2) how such effects are related to gene expression and receptor maps. METHODS: Across 115 participants (37 control, 39 remitted MDD, 39 current MDD), we evaluated the effects of stress on FC during the Montreal Imaging Stress Task. Using partial least squares regression, we investigated genes whose expression in the Allen Human Brain Atlas was associated with anatomical patterns of stress-related FC change. Finally, we correlated stress-related FC change maps with opioid and GABAA (gamma-aminobutyric acid A) receptor distribution maps derived from positron emission tomography. RESULTS: Results revealed robust effects of stress on global cortical connectivity, with increased global FC in frontoparietal and attentional networks and decreased global FC in the medial default mode network. Moreover, robust increases emerged in FC of the caudate, putamen, and amygdala with regions from the ventral attention/salience network, frontoparietal network, and motor networks. Such regions showed preferential expression of genes involved in cell-to-cell signaling (OPRM1, OPRK1, SST, GABRA3, GABRA5), similar to previous genetic MDD studies. CONCLUSIONS: Acute stress altered global cortical connectivity and increased striatal connectivity with cortical regions that express genes that have previously been associated with imaging abnormalities in MDD and are rich in µ and κ opioid receptors. These findings point to overlapping circuitry underlying stress response, reward, and MDD.
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Background: Proteomics offers potential for detecting and monitoring anorexia nervosa (AN) and its variant, atypical AN (atyp-AN). However, research has been limited by small protein panels, a focus on adult AN, and lack of replication. Methods: In this study, we performed Olink multiplex profiling of 92 inflammation-related proteins in females with AN/atyp-AN (n = 64), all of whom were ≤90% of expected body weight, and age-matched healthy control individuals (n = 44). Results: Five proteins differed significantly between the primary AN/atyp-AN group and the healthy control group (lower levels: HGF, IL-18R1, TRANCE; higher levels: CCL23, LIF-R). The expression levels of 3 proteins (lower IL-18R1, TRANCE; higher LIF-R) were uniquely disrupted in participants with AN in our primary model. No unique expression levels emerged for atyp-AN. In the total sample, 12 proteins (ADA, CD5, CD6, CXCL1, FGF-21, HGF, IL-12B, IL18, IL-18R1, SIRT2, TNFSF14, TRANCE) were positively correlated with body mass index and 5 proteins (CCL11, FGF-19, IL8, LIF-R, OPG) were negatively correlated with body mass index in our primary models. Conclusions: Our results replicate the results of a previous study that demonstrated a dysregulated inflammatory status in AN and extend those results to atyp-AN. Of the 17 proteins correlated with body mass index, 11 were replicated from a previous study that used similar methods, highlighting the promise of inflammatory protein expression levels as biomarkers of AN disease monitoring. Our findings underscore the complexity of AN and atyp-AN by highlighting the inability of the identified proteins to differentiate between these 2 subtypes, thereby emphasizing the heterogeneous nature of these disorders.
We examined 73 inflammation proteins in adolescent girls with anorexia nervosa (AN) and atypical AN and compared them with age-matched healthy control girls. Significant differences were found, driven by 5 key proteins (lower: HGF, IL-18R1, TRANCE; higher: CCL23, LIF-R). Three proteins (TRANCE, LIF-R, IL-18R1) uniquely distinguished low-weight participants with AN from control participants. Our study reveals distinct inflammation patterns in AN and atypical AN and sheds light on potential state-specific factors that underlie these disorders.
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OBJECTIVE: Preclinical work suggests that excess glucocorticoids and reduced cortical γ-aminobutyric acid (GABA) may affect sex-dependent differences in brain regions implicated in stress regulation and depressive phenotypes. The authors sought to address a critical gap in knowledge, namely, how stress circuitry is functionally affected by glucocorticoids and GABA in current or remitted major depressive disorder (MDD). METHODS: Multimodal imaging data were collected from 130 young adults (ages 18-25), of whom 44 had current MDD, 42 had remitted MDD, and 44 were healthy comparison subjects. GABA+ (γ-aminobutyric acid and macromolecules) was assessed using magnetic resonance spectroscopy, and task-related functional MRI data were collected under acute stress and analyzed using data-driven network modeling. RESULTS: Across modalities, trait-related abnormalities emerged. Relative to healthy comparison subjects, both clinical groups were characterized by lower rostral anterior cingulate cortex (rACC) GABA+ and frontoparietal network amplitude but higher amplitude in salience and stress-related networks. For the remitted MDD group, differences from the healthy comparison group emerged in the context of elevated cortisol levels, whereas the MDD group had lower cortisol levels than the healthy comparison group. In the comparison group, frontoparietal and stress-related network connectivity was positively associated with cortisol level (highlighting putative top-down regulation of stress), but the opposite relationship emerged in the MDD and remitted MDD groups. Finally, rACC GABA+ was associated with stress-induced changes in connectivity between overlapping default mode and salience networks. CONCLUSIONS: Lifetime MDD was characterized by reduced rACC GABA+ as well as dysregulated cortisol-related interactions between top-down control (frontoparietal) and threat (task-related) networks. These findings warrant further investigation of the role of GABA in the vulnerability to and treatment of MDD.
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Trastorno Depresivo Mayor , Giro del Cíngulo , Hidrocortisona , Imagen por Resonancia Magnética , Imagen Multimodal , Estrés Psicológico , Ácido gamma-Aminobutírico , Humanos , Giro del Cíngulo/fisiopatología , Giro del Cíngulo/metabolismo , Giro del Cíngulo/diagnóstico por imagen , Masculino , Hidrocortisona/metabolismo , Femenino , Adulto , Adulto Joven , Ácido gamma-Aminobutírico/metabolismo , Trastorno Depresivo Mayor/fisiopatología , Trastorno Depresivo Mayor/diagnóstico por imagen , Trastorno Depresivo Mayor/metabolismo , Trastorno Depresivo Mayor/tratamiento farmacológico , Adolescente , Estrés Psicológico/metabolismo , Estrés Psicológico/fisiopatología , Estrés Psicológico/diagnóstico por imagen , Espectroscopía de Resonancia Magnética , Conectoma , Estudios de Casos y Controles , Red Nerviosa/fisiopatología , Red Nerviosa/diagnóstico por imagenRESUMEN
BACKGROUND: Accumulating preclinical and preliminary translational evidence shows that the hypothalamic peptide oxytocin reduces food intake, increases energy expenditure, and promotes weight loss. It is currently unknown whether oxytocin administration is effective in treating human obesity. METHODS: In this randomized, double-blind, placebo-controlled trial, we randomly assigned adults with obesity 1:1 (stratified by sex and obesity class) to receive intranasal oxytocin (24 IU) or placebo four times daily for 8 weeks. The primary end point was change in body weight (kg) from baseline to week 8. Key secondary end points included change in body composition (total fat mass [g], abdominal visceral adipose tissue [cm2], and liver fat fraction [proportion; range, 0 to 1; higher values indicate a higher proportion of fat]), and resting energy expenditure (kcal/day; adjusted for lean mass) from baseline to week 8 and caloric intake (kcal) at an experimental test meal from baseline to week 6. RESULTS: Sixty-one participants (54% women; mean age ± standard deviation, 33.6 ± 6.2 years; body-mass index [the weight in kilograms divided by the square of the height in meters], 36.9 ± 4.9) were randomly assigned. There was no difference in body weight change from baseline to week 8 between oxytocin and placebo groups (0.20 vs. 0.26 kg; P=0.934). Oxytocin (vs. placebo) was not associated with beneficial effects on body composition or resting energy expenditure from baseline to week 8 (total fat: difference [95% confidence interval], 196.0 g [-1036 to 1428]; visceral fat: 3.1 cm2 [-11.0 to 17.2]; liver fat: -0.01 [-0.03 to 0.01]; resting energy expenditure: -64.0 kcal/day [-129.3 to 1.4]). Oxytocin compared with placebo was associated with reduced caloric intake at the test meal (-31.4 vs. 120.6 kcal; difference [95% confidence interval], -152.0 kcal [-302.3 to -1.7]). There were no serious adverse events. Incidence and severity of adverse events did not differ between groups. CONCLUSIONS: In this randomized, placebo-controlled trial in adults with obesity, intranasal oxytocin administered four times daily for 8 weeks did not reduce body weight. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others; ClinicalTrials.gov number, NCT03043053.).
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Administración Intranasal , Obesidad , Oxitocina , Humanos , Oxitocina/administración & dosificación , Oxitocina/farmacología , Oxitocina/efectos adversos , Femenino , Masculino , Adulto , Obesidad/tratamiento farmacológico , Método Doble Ciego , Metabolismo Energético/efectos de los fármacos , Composición Corporal/efectos de los fármacos , Ingestión de Energía/efectos de los fármacos , Pérdida de Peso/efectos de los fármacosRESUMEN
Major Depressive Disorder (MDD) is a heterogenous and etiologically complex disease encompassing a broad spectrum of psychopathology, presumably arising from distinct pathophysiological mechanisms. Divergent appetitive phenotypes including Hyperphagic MDD (characterized by an increased appetite) and Hypophagic MDD (characterized by a decrease in appetite) are important clinical characteristics that are closely related to comorbidities, including cardiometabolic disorders. Prior evidence supports the notion that hyperphagia is associated with atypical depression, decreased stress-hormone signaling, a pro-inflammatory status, hypersomnia, and poorer clinical outcomes. Yet, our understanding of the underlying mechanisms of Hyperphagic and Hypophagic MDD is limited, and knowledge of associated biological correlates of these endophenotypes remain fragmented. We performed an exploratory study on peripheral blood RNA profiling using bulk RNAseq in unmedicated individuals with Hyperphagic and Hypophagic MDD (n=8 and n=13, respectively) and discovered individual genes and gene pathways associated with appetitive phenotypes. In addition, we used the Maastricht Acute Stress Task to uncover stress-related transcriptomic profiles in Hyper- and Hypophagic MDD.
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Importance: Individuals with anorexia nervosa maintain extremely low body weights despite elevations in the circulating orexigenic hormone ghrelin. Whether circulating levels of endogenous ghrelin are associated with weight gain in anorexia nervosa is unknown. Objective: To examine the association between baseline ghrelin and future weight change in individuals with anorexia nervosa. Design, Setting, and Participants: This prospective cohort study was conducted between April 1, 2014, and March 31, 2020, in the US. Girls and women aged 10 to 22 years were recruited from the greater Boston area from community and area treatment centers, enrolled, and followed up for 18 months. Statistical analyses were performed between January and August 2022. Exposures: Presence or absence of anorexia nervosa and elevations in endogenous ghrelin. Main Outcomes and Measures: Changes in age- and sex-standardized body mass index percentiles from baseline to 9- and 18-month follow-up were the main outcomes of interest. Results: A total of 68 girls and young women (11 [16%] Asian, 4 [6%] Hispanic or Latina, 51 [75%] White [non-Hispanic or Latina], and 2 [3%] other race or ethnicity), including 35 with anorexia nervosa and 33 healthy controls of similar Tanner stage, were included in this study. Anorexia nervosa and healthy control groups were not statistically different by race and ethnicity, Tanner stage, number completing follow-up visits, and the duration between baseline and follow-up visits. At baseline, individuals with anorexia nervosa were slightly older (median [IQR], 20.1 [18.5-21.0] vs 18.7 [14.7-19.4] years; P = .005), had lower body mass index percentiles (median [IQR], 2.4 [0.3-4.7] vs 52.9 [40.4-68.3]; P < .001), and had elevated circulating ghrelin area under the curve composite index (median [IQR], 1389.4 [1082.5-1646.4] vs 958.5 [743.0-1234.5] pg/mL; P = .003) compared with healthy individuals. In linear mixed-effects regression analyses, baseline ghrelin was associated with prospective weight gain after adjusting for diagnosis, age, race, and duration of follow-up (odds ratio, 2.35; 95% CI, 1.43-3.73; P = .004). Conclusions and Relevance: In this cohort study, endogenous ghrelin was associated with longitudinal weight gain in individuals with anorexia nervosa. Further studies are warranted to confirm this result and examine its potential clinical utility in treatment development.
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Anorexia Nerviosa , Trayectoria del Peso Corporal , Femenino , Humanos , Ghrelina , Estudios Prospectivos , Estudios de Cohortes , Aumento de PesoRESUMEN
OBJECTIVE: The amygdaloid complex is a subcortical limbic group of distinct nuclei. In a previous patient-control study, differential amygdala nuclei alterations were found in acute anorexia nervosa (AN); rostral-medial nuclei involved in fear and reward processing were substantially reduced in volume and associated with hypoleptinemia, a key neuroendocrine characteristic of AN. Here, longitudinal amygdala nuclei alterations in AN were investigated in relation to weight status and their associations with leptin levels. METHOD: T1-weighted structural magnetic resonance imaging scans were longitudinally processed with FreeSurfer. Amygdala nuclei volumes in young female patients with acute AN before and after short-term weight restoration (n = 110, >14% body mass index increase over 3 months) and female participants with a history of AN (n = 79, long-term [mean 5 years] weight recovered) were compared with female healthy control participants (n = 271) using linear mixed effects models. RESULTS: Rostral-medially clustered amygdala nuclei volumes, accessory basal, cortical, medial nuclei, and corticoamygdaloid transition, increased during short-term weight restoration (Cohen's d range 0.18-0.30). However, volumetric normalization across nuclei was heterogeneous. Right cortical, medial nuclei, bilateral corticoamygdaloid transitions, and anterior amygdaloid areas were only partially normalized following short-term weight restoration. Right anterior amygdaloid area remained reduced after long-term weight recovery compared with control participants (d = 0.36). Leptin increase, accompanying short-term weight restoration, mediated the effect of weight gain on volumetric increase in left corticoamygdaloid transition and bilateral medial nuclei. CONCLUSION: Rostral-medially clustered amygdala nuclei show pronounced volumetric increase but incomplete normalization in AN during and after short-term weight restoration. Leptin increase may be relevant for the recovery of specific amygdala nuclei in addition to nutritional rehabilitation, indicating links between amygdala substructure and leptin dynamics of potential pathophysiological and clinical relevance in AN. PLAIN LANGUAGE SUMMARY: The amygdala plays a critical role in processing fearful and rewarding stimuli, and alterations in the amygdala are associated with anorexia nervosa. In this study, the authors measured amygdala nuclei volumes in female patients with acute anorexia nervosa undergoing weight-restoration treatment (n = 110), long-term weight-recovered individuals with anorexia (n = 79), and healthy control participants (n = 271). Structural magnetic resonance imaging revealed that volumes of specific nuclei, clustered in the rostral-medial amygdala, were substantially reduced in acute anorexia nervosa and only partially normalized following weight restoration treatment. Residual reductions in volume persisted even after long-term weight-recovery, compared to healthy control participants. Short-term weight restoration was associated with increases in the neurohormone leptin, and increasing leptin levels were found to mediate the positive impact of weight gain on increased amygdala volume over the treatment course. DIVERSITY & INCLUSION STATEMENT: We worked to ensure race, ethnic, and/or other types of diversity in the recruitment of human participants. We worked to ensure that the study questionnaires were prepared in an inclusive way. One or more of the authors of this paper received support from a program designed to increase minority representation in science. We actively worked to promote sex and gender balance in our author group. We actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our author group. While citing references scientifically relevant for this work, we also actively worked to promote sex and gender balance in our reference list. While citing references scientifically relevant for this work, we also actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our reference list. The author list of this paper includes contributors from the location and/or community where the research was conducted who participated in the data collection, design, analysis, and/or interpretation of the work.
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Increase in stress-related disorders in women begins post-puberty and persists throughout the lifespan. To characterize sex differences in stress response in early adulthood, we used functional magnetic resonance imaging while participants underwent a stress task in conjunction with serum cortisol levels and questionnaires assessing anxiety and mood. Forty-two healthy subjects aged 18-25 years participated (21M, 21F). Interaction of stress and sex in brain activation and connectivity were examined. Results demonstrated significant sex differences in brain activity with women exhibiting increased activation in regions that inhibit arousal compared to men during the stress paradigm. Women had increased connectivity among stress circuitry regions and default mode network, whereas men had increased connectivity between stress and cognitive control regions. In a subset of subjects (13F, 17M), we obtained gamma-aminobutyric acid (GABA) magnetic resonance spectroscopy in rostral anterior cingulate cortex (rostral ACC) and dorsolateral prefrotal cortex (dlPFC) and conducted exploratory analyses to relate GABA measurements with sex differences in brain activation and connectivity. Prefrontal GABA levels were negatively associated with inferior temporal gyrus activation in men and women and with ventromedial prefrontal cortex activation in men. Despite sex differences in neural response, we found similar subjective ratings of anxiety and mood, cortisol levels, and GABA levels between sexes, suggesting sex differences in brain activity result in similar behavioral responses among the sexes. These results help establish sex differences in healthy brain activity from which we can better understand sex differences underlying stress-associated illnesses.
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Corteza Cerebral , Hidrocortisona , Humanos , Masculino , Femenino , Adulto Joven , Adulto , Adolescente , Corteza Cerebral/fisiología , Encéfalo/diagnóstico por imagen , Giro del Cíngulo , Ácido gamma-AminobutíricoRESUMEN
Objective: Avoidant/restrictive food intake disorder (ARFID) is associated with increased risk for anxiety, which may adversely affect prognosis. The appetite-stimulating hormone, ghrelin, increases in response to stress, and exogenous ghrelin decreases anxiety-like behaviors in animal models. The aim of this study was to evaluate the relationship between ghrelin levels and measures of anxiety in youth with ARFID. We hypothesized that lower ghrelin levels would be associated with increased anxiety symptoms.Methods: We studied a cross-sectional sample of 80 subjects with full and subthreshold ARFID diagnosed by DSM-5 criteria, aged 10-23 years (female, n = 39; male, n = 41). Subjects were enrolled in a study of the neurobiology of avoidant/restrictive eating conducted from August 2016 to January 2021. We assessed fasting ghrelin levels and anxiety symptoms (State-Trait Anxiety Inventory [STAI] and STAI for Children [STAI-C] measuring general trait anxiety; Beck Anxiety Inventory [BAI] and BAI for youth [BAI-Y] assessing cognitive, emotional, and somatic symptoms of anxiety; and Liebowitz Social Anxiety Scale [LSAS] assessing symptoms of social anxiety).Results: Consistent with our hypothesis, ghrelin levels were inversely associated with anxiety symptoms as assessed by STAI/STAI-C T scores (r = -0.28, P = .012), BAI/BAI-Y T scores (r = -0.28, P = .010), and LSAS scores (r = -0.3, P = .027), all with medium effect sizes. Findings held in the full threshold ARFID group when adjusting for body mass index z scores (STAI/STAI-C T scores, ß = -0.27, P = .024; BAI/BAI-Y T scores, ß = -0.26, P = .034; LSAS, ß = -0.34, P = .024).Conclusions: These findings demonstrate that lower levels of ghrelin are associated with more severe anxiety symptoms in youth with ARFID and raise the question of whether ghrelin pathways could be targeted in the treatment of ARFID.
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Trastorno de la Ingesta Alimentaria Evitativa/Restrictiva , Trastornos de Alimentación y de la Ingestión de Alimentos , Masculino , Humanos , Femenino , Ghrelina , Estudios Transversales , Ansiedad/diagnóstico , Ingestión de Alimentos , Estudios RetrospectivosRESUMEN
Anorexia nervosa (AN) and atypical AN (AtypAN) are complex neurobiological illnesses that typically onset in adolescence with an often treatment-refractory and chronic illness trajectory. Aberrant eating behaviors in this population have been linked to abnormalities in food reward and cognitive control, but prior studies have not examined respective contributions of clinical characteristics and metabolic state. Research is needed to identify specific disruptions and inform novel intervention targets to improve outcomes. Fifty-nine females with AN (n = 34) or AtypAN (n = 25), ages 10-22 years, all ≤90% expected body weight, and 34 age-matched healthy controls (HC) completed a well-established neuroimaging food cue paradigm fasting and after a standardized meal, and we used ANCOVA models to investigate main and interaction effects of Group and Appetitive State on blood oxygenation level-dependent (BOLD) activation for the contrast of exposure to high-calorie food images minus objects. We found main effects of Group with greater BOLD activation in the dorsal anterior cingulate cortex (dACC), dorsolateral prefrontal cortex (DLPFC), hippocampus, caudate, and putamen for AN/AtypAN versus HC groups, and in the three-group model including AN, AtypAN, and HC (sub-)groups, where differences were primarily driven by greater activation in the AtypAN subgroup versus HC group. We found a main effect of Appetitive State with increased premeal BOLD activation in the hypothalamus, amygdala, nucleus accumbens, and caudate for models that included AN/AtypAN and HC groups, and in BOLD activation in the nucleus accumbens for the model that included AN, AtypAN, and HC (sub-)groups. There were no interaction effects of Group with Appetitive State for any of the models. Our findings demonstrate robust feeding-state independent group effects reflecting greater neural activation of specific regions typically associated with reward and cognitive control processing across AN and AtypAN relative to healthy individuals in this food cue paradigm. Differential activation of specific brain regions in response to the passive viewing of high-calorie food images may underlie restrictive eating behavior in this clinical population.