Efficacy of pharmacotherapies for bulimia nervosa: a systematic review and meta-analysis.

OBJECTIVE: The main purpose was to evaluate the efficacy and tolerability of different medications used to treat bulimia nervosa (BN). METHODS: Randomized controlled trials (RCTs) were identified from published sources through searches in PubMed, Cochrane Library, Web of Science, and Embase from inception to November 2022. Primary outcomes were changes in the frequency of binge eating episodes and vomiting episodes from baseline to endpoint. Secondary outcomes were differences in the improvement of scores in depressive symptoms, tolerability (dropout due to adverse events) and weight change. RESULTS: The literature search ultimately included 11 drugs, 33 studies and 6 types of drugs, 8 trials with TCAs (imipramine, desipramine), 14 with SSRIs (fluoxetine, citalopram and fluvoxamine), 6 with MAOIs (phenelzine, moclobemide and brofaromine), 3 with antiepileptic drugs (topiramate), 1 with mood stabilizers (lithium), and 1 with amphetamine-type appetite suppressant (fenfluramine). The reduction in binge eating episodes was more likely due to these drugs than the placebo, and the SMD was -0.4 (95% CI -0.61 ~ -0.19); the changes in the frequency of vomiting episodes (SMD = -0.16, 95% CI -0.3 ~ -0.03); weight (WMD = -3.05, 95% CI -5.97 ~ -0.13); and depressive symptoms (SMD = -0.32, 95% CI -0.51 ~ -0.13). However, no significant difference was found in dropout due to adverse events (RR = 1.66, 95% CI 1.14 ~ 2.41). CONCLUSIONS: This meta-analysis indicates that most pharmacotherapies decreased the frequency of binge-eating and vomiting episodes, body weight, and depressive symptoms in BN patients, but the efficacy was not significant. In each drug the efficacy is different, treating different aspects, different symptoms to improve the clinical performance of bulimia nervosa.

The neuromedin U system: Pharmacological implications for the treatment of obesity and binge eating behavior.

Neuromedin U (NMU) is a bioactive peptide produced in the gut and in the brain, with a role in multiple physiological processes. NMU acts by binding and activating two G protein coupled receptors (GPCR), the NMU receptor 1 (NMU-R1), which is predominantly expressed in the periphery, and the NMU receptor 2 (NMU-R2), mainly expressed in the central nervous system (CNS). In the brain, NMU and NMU-R2 are consistently present in the hypothalamus, commonly recognized as the main "feeding center". Considering its distribution pattern, NMU revealed to be an important neuropeptide involved in the regulation of food intake, with a powerful anorexigenic ability. This has been observed through direct administration of NMU and by studies using genetically modified animals, which revealed an obesity phenotype when the NMU gene is deleted. Thus, the development of NMU analogs or NMU-R2 agonists might represent a promising pharmacological strategy to treat obese individuals. Furthermore, NMU has been demonstrated to influence the non-homeostatic aspect of food intake, playing a potential role in binge eating behavior. This review aims to discuss and summarize the current literature linking the NMU system with obesity and binge eating behavior, focusing on the influence of NMU on food intake and the neuronal mechanisms underlying its anti-obesity properties. Pharmacological strategies to improve the pharmacokinetic profile of NMU will also be reported.

Naltrexone plus bupropion combination medication maintenance treatment for binge-eating disorder following successful acute treatments: randomized double-blind placebo-controlled trial.

BACKGROUND: Certain treatments have demonstrated acute efficacy for binge-eating disorder (BED) but there is a dearth of controlled research examining pharmacotherapies as maintenance treatments for responders to initial interventions. This gap in the literature is particularly critical for pharmacotherapy for BED which is associated with relapse following discontinuation. The current study tested the efficacy of naltrexone/bupropion maintenance treatment amongst responders to acute treatments for BED. METHODS: Prospective randomized double-blind placebo-controlled single-site trial, conducted August 2017-December 2021, tested naltrexone/bupropion as maintenance treatment for responders to acute treatments with naltrexone/bupropion and/or behavioral weight-loss therapy for BED with comorbid obesity. Sixty-six patients (84.8% women, mean age 46.9, mean BMI 34.9 kg/m2) who responded to acute treatments were re-randomized to placebo (N = 34) or naltrexone/bupropion (N = 32) for 16 weeks; 86.3% completed posttreatment assessments. Mixed models and generalized estimating equations comparing maintenance treatments (naltrexone/bupropion v. placebo) included main and interactive effects of acute treatments. RESULTS: Intention-to-treat binge-eating remission rates following maintenance treatments were 50.0% (N = 17/34) for placebo and 68.8% (N = 22/32) for naltrexone/bupropion. Placebo following response to acute treatment with naltrexone/bupropion was associated with significantly decreased probability of binge-eating remission, increased binge-eating frequency, and no weight loss. Naltrexone/bupropion following response to acute treatment with naltrexone/bupropion was associated with good maintenance of binge-eating remission, low binge-eating frequency, and significant additional weight loss. CONCLUSIONS: Adult patients with BED with co-occurring obesity who have good responses to acute treatment with naltrexone/bupropion should be offered maintenance treatment with naltrexone/bupropion.

Treatment of eating disorders: A systematic meta-review of meta-analyses and network meta-analyses.

MONTELEONE, A.M., F. Pellegrino, G. Croatto, M. Carfagno, A. Hilbert, J. Treasure, T. Wade, C. Bulik, S. Zipfel, P. Hay, U. Schmidt, G. Castellini, A. Favaro, F. Fernandez-Aranda, J. Il Shin, U. Voderholzer, V. Ricca, D. Moretti, D. Busatta, G. Abbate-Daga, F. Ciullini, G. Cascino, F. Monaco, C.U. Correll and M. Solmi. Treatment of Eating Disorders: a systematic meta-review of meta-analyses and network meta-analyses. NEUROSCI BIOBEHAV REV 21(1) XXX-XXX, 2022.- Treatment efficacy for eating disorders (EDs) is modest and guidelines differ. We summarized findings/quality of (network) meta-analyses (N)MA of randomized controlled trials (RCTs) in EDs. Systematic meta-review ((N)MA of RCTs, ED, active/inactive control), using (anorexia or bulimia or eating disorder) AND (meta-analy*) in PubMed/PsycINFO/Cochrane database up to December 15th, 2020. Standardized mean difference, odds/risk ratio vs control were summarized at end of treatment and follow-up. Interventions involving family (family-based therapy, FBT) outperformed active control in adults/adolescents with anorexia nervosa (AN), and in adolescents with bulimia nervosa (BN). In adults with BN, individual cognitive behavioural therapy (CBT)-ED had the broadest efficacy versus active control; also, antidepressants outperformed active. In mixed age groups with binge-eating disorder (BED), psychotherapy, and lisdexamfetamine outperformed active control. Antidepressants, stimulants outperformed placebo, despite lower acceptability, as did CBT-ED versus waitlist/no treatment. Family-based therapy is effective in AN and BN (adolescents). CBT-ED has the largest efficacy in BN (adults), followed by antidepressants, as well as psychotherapy in BED (mixed). Medications have short-term efficacy in BED (adults).

Brain serotonin deficiency and fluoxetine lead to sex-specific effects on binge-like food consumption in mice.

RATIONALE: Although pharmacotherapies are often effective in reducing binge eating in conditions such as bulimia nervosa and binge eating disorder, subsets of patients do not benefit sufficiently from existing treatments, and the reasons for treatment failure remain unclear. OBJECTIVES: This study aimed to evaluate whether genetic reductions in brain serotonin influence binge eating and/or the ability of fluoxetine, a selective serotonin reuptake inhibitor, to reduce binge eating in mice. METHODS: This study used a validated model of binge-like consumption of high-fat diet to compare binge-like food intake in control and fluoxetine-treated wild-type and serotonin-deficient mice from the tryptophan hydroxylase 2 (R439H) knock-in line. In addition, real-time PCR was used to evaluate potential genotype and sex differences in the effects of fluoxetine on gene expression in the raphe nucleus. RESULTS: The results reveal that brain serotonin deficiency is sufficient to increase binge eating in males, but not females. However, while chronic fluoxetine reduced binge eating in both genotypes of males and in wild-type females, it failed to reduce binge eating in serotonin-deficient females. Transcriptional responses to chronic fluoxetine were also characterized by sex and genotype differences. CONCLUSIONS: Overall, this study revealed significant sex differences in the effects of fluoxetine and brain serotonin deficiency on binge-like food intake and suggests that low brain serotonin could impact eating disorders both by promoting binge eating and by limiting the efficacy of fluoxetine to reduce binge eating.

GABAB receptor signaling in the caudate putamen is involved in binge-like consumption during a high fat diet in mice.

Previous studies suggest that signaling by the gamma-aminobutyric acid (GABA) type B receptor (GABABR) is involved in the regulation of binge eating, a disorder which might contribute to the development of obesity. Here, we show that intermittent access to a high fat diet (HFD) induced binge-like eating behavior with activation of dopamine receptor d1 (drd1)-expressing neurons in the caudate putamen (CPu) and nucleus accumbens (NAc) in wild-type (WT) mice. The activation of drd1-expressing neurons during binge-like eating was substantially increased in the CPu, but not in the NAc, in corticostriatal neuron-specific GABABR-deficient knockout (KO) mice compared to WT mice. Treatment with the GABABR agonist, baclofen, suppressed binge-like eating behavior in WT mice, but not in KO mice, as reported previously. Baclofen also suppressed the activation of drd1-expressing neurons in the CPu, but not in the NAc, during binge-like eating in WT mice. Thus, our data suggest that GABABR signaling in CPu neurons expressing drd1 suppresses binge-like consumption during a HFD in mice.

Emerging Benefits: Pathophysiological Functions and Target Drugs of the Sigma-1 Receptor in Neurodegenerative Diseases.

The sigma-1 receptor (Sig-1R) is encoded by the SIGMAR1 gene and is a nonopioid transmembrane receptor located in the mitochondrial-associated endoplasmic reticulum membrane (MAM). It helps to locate endoplasmic reticulum calcium channels, regulates calcium homeostasis, and acts as a molecular chaperone to control cell fate and participate in signal transduction. It plays an important role in protecting neurons through a variety of signaling pathways and participates in the regulation of cognition and motor behavior closely related to neurodegenerative diseases. Based on its neuroprotective effects, Sig-1R has now become a breakthrough target for alleviating Alzheimer's disease and other neurodegenerative diseases. This article reviews the most cutting-edge research on the function of Sig-1R under normal or pathologic conditions and target drugs of the sigma-1 receptor in neurodegenerative diseases.

Efficacy and safety of dasotraline in adults with binge-eating disorder: a randomized, placebo-controlled, fixed-dose clinical trial.

OBJECTIVE: The aim of this fixed-dose study was to evaluate the efficacy and safety of dasotraline in the treatment of patients with binge-eating disorder (BED). METHODS: Patients meeting Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition criteria for BED were randomized to 12 weeks of double-blind treatment with fixed doses of dasotraline (4 and 6 mg/d), or placebo. The primary efficacy endpoint was change in number of binge-eating (BE) days per week at week 12. Secondary efficacy endpoints included week 12 change on the BE CGI-Severity Scale (BE-CGI-S) and the Yale-Brown Obsessive-Compulsive Scale Modified for BE (YBOCS-BE). RESULTS: At week 12, treatment with dasotraline was associated with significant improvement in number of BE days per week on the dose of 6 mg/d (N = 162) vs placebo (N = 162; -3.47 vs -2.92; P = .0045), but not 4 mg/d (N = 161; -3.21). Improvement vs placebo was observed for dasotraline 6 and 4 mg/d, respectively, on the BE-CGI-S (effect size [ES]: 0.37 and 0.27) and on the YBOCS-BE total score (ES: 0.43 and 0.29). The most common adverse events on dasotraline were insomnia, dry mouth, headache, decreased appetite, nausea, and anxiety. Changes in blood pressure and pulse were minimal. CONCLUSION: Treatment with dasotraline 6 mg/d (but not 4 mg/d) was associated with significantly greater reduction in BE days per week. Both doses of dasotraline were generally safe and well-tolerated and resulted in global improvement on the BE-CGI-S, as well as improvement in BE related obsessional thoughts and compulsive behaviors on the YBOCS-BE. These results confirm the findings of a previous flexible dose study.

An assessment of rapamycin for weakening binge-eating memories via reconsolidation: a pre-registered, double-blind randomised placebo-controlled experimental study.

BACKGROUND: Maladaptive learning linking environmental food cues to high-palatability food reward plays a central role in overconsumption in obesity and binge eating disorders. The process of memory reconsolidation offers a mechanism to weaken such learning, potentially ameliorating over-eating behaviour. Here we investigated whether putatively interfering with synaptic plasticity using the mammalian target of rapamycin (mTOR) inhibitor, rapamycin, could weaken retrieved chocolate reward memories through blockade of reconsolidation. METHODS: Seventy five healthy volunteers with a tendency to binge eat chocolate were randomised to retrieve chocolate reward memory under 10 mg rapamycin (RET + RAP, active condition), or placebo (RET + PBO), or they received 10 mg rapamycin without subsequent retrieval (NO RET + RAP). Indices of chocolate reward memory strength were assessed one week pre and post manipulation and at one month follow-up. RESULTS: Contrary to hypotheses, the RET + RAP group did not show any greater reduction than control groups on indices of motivational salience of chocolate cues, motivation to consume chocolate or liking of chocolate. Mild evidence of improvement in the RET + RAP group was found, but this was limited to reduced chocolate binge episodes and improved healthy food choices. CONCLUSIONS: We did not find convincing evidence of comprehensive naturalistic chocolate reward memory reconsolidation blockade by rapamycin. The effects on chocolate bingeing and food choices may warrant further investigation. These limited positive findings may be attributable to insufficient interference with mTOR signalling with 10 mg rapamycin, or failure to destabilise chocolate memories during retrieval.

Efficacy and safety of topiramate in binge eating disorder: a systematic review and meta-analysis.

BACKGROUND: To assess the efficacy and safety of topiramate in treating binge eating disorder (BED), using a systematic review and meta-analysis of the available randomized clinical trials (RCTs). METHODS: The RCTs assessing topiramate vs placebo with or without adjunctive psychotherapy in BED were reviewed using a systematic search in the PubMed, Web of Science, PsycINFO, Cochrane Database of Systematic Review, and ClinicalTrials.gov search Websites, from inception to November 2019. Main outcomes were the changes in binge frequency, quality of life, and weight, respectively. Effect estimates were pooled using random-effect models and presented as risk ratios (RRs) or mean differences (MDs) and their 95% confidence interval (95% CI). Data extraction was performed by two independent reviewers. RESULTS: Three studies were eligible for inclusion, involving 528 BED patients. Topiramate was found to be significantly more efficacious than placebo in reducing: (a) the number of binge episodes per week (MD = -1.31; 95% CI = -2.58 to -0.03; I2 = 94%); (b) the number of binge days per week (MD = -0.98; 95% CI = -1.80 to -0.16; I2 = 94%); and (c) weight (MD = -4.91 kg; 95% CI = -6.42 to -3.41; I2 = 10%). However, participants in the topiramate groups withdrew significantly more frequently for safety reasons, relative to placebo participants (RR = 1.90; 95% CI = 1.13-3.18, I2 = 0%). CONCLUSIONS: Preliminary findings support a possible efficacy of topiramate for the treatment of BED, even if safety concerns could limit the practical use of this treatment in BED subjects.

Lisdexamfetamine suppresses instrumental and consummatory behaviors supported by foods with varying degrees of palatability: Exploration of a binge-like eating model.

Diets high in sugar or fat are associated with multiple health conditions, including binge eating disorder (BED). BED affects approximately 2% of the US adult population, and occurs more frequently in females. It is important to develop animal models of palatable food consumption and food seeking that may have relevance for BED and other conditions associated with excessive food intake. The catecholamine uptake blocker and d-amphetamine prodrug lisdexamfetamine is used to treat BED. The present experiments studied the effect of lisdexamfetamine on food intake and food-reinforced effort-based choice in female Wistar rats. Three groups of rats received different food exposure conditions in the home cage randomly spread over several weeks: a chocolate exposure group (CE; brief access of chocolate and additional lab chow, n = 15), a lab chow exposure (LChE) group given additional access to lab chow (n = 8), and a third group given empty food dishes (n = 7). In tests of food intake under non-restricted conditions, lisdexamfetamine (0.1875-1.5 mg/kg IP) significantly reduced intake of both chocolate and chow in the CE group. In the LChE group, there was a trend towards reduced chow intake induced by lisdexamfetamine. All rats were trained on a Progressive Ratio/chow feeding choice task, in which they had a choice between working for high carbohydrate chocolate flavored pellets by lever pressing vs. approaching and consuming a concurrently available lab chow. The LChE group and the empty food dish group were combined to create one control group (n = 15). There was a significant overall dose-related suppressive effect of lisdexamfetamine on lever pressing but no group difference, and no dose x group interaction. Lisdexamfetamine significantly decreased chow intake in the CE group, but not in the control group. In conclusion, lisdexamfetamine affected both food intake and food-reinforced operant behavior, with larger effects seen in the group exposed to chocolate.

[The effect of pectin of tansy, Tanacetum vulgare L., on anxiety and overeating food rich in fats and sugars in mice in modelling binge eating].

Binge eating is repeated episodes of eating large amounts of sweet and fatty food in short periods. Dietary fibers, including pectin, significantly reduce the subjective ratings of hunger, and the amount of food eaten. However, studies showing the effect of dietary fibers on satiety use juices or yoghurts with added dietary fiber, or a kissel-like food. Thus, there is a lack of data on the effect of dietary fibres on binge eating of palatable food. The aim of the study was to assess the effect of tansy pectin on anxiety and the binge eating of palatable food in mice. Material and methods. 64 mice weighing 33.3±0.6 g were divided into two groups. Binge eating was induced in forty mice of the first group by consumption of sunflower halva (SH) in addition to regular chow for 24 h once a week. The total energy intake and separately the consumption of regular chow (RC) and SH were monitored. Tansy pectin in the form of an aqueous solution was administered to the mice using a gastric feeding tube (50 mg/kg body weight) before the last presentation of SH. Blood was obtained by cardiac puncture at the end of the last 24 h SH access period. The concentration of insulin and ghrelin in plasma samples were determined by the enzyme immunoassay. In animals of the second group, 24 hours after the administration of pectin, the level of anxiety and depression of mice was assayed with an open field test, a light-dark box test, an elevated plus-maze test, and a forced swim test. Throughout the study, water was used as a negative control, and imipramine at a dose of 20 mg/kg was used as a positive control. Results. Mice treated with tansy pectin ate 2.6 fold less SH within 3 h and 1.4 fold less within 24 h after oral administration of tansy pectin compared to control (water administration). Consumption of RC did not differ within 3 or 24 h. The total energy intake was 1.9 fold lower within 3 h in mice treated with tansy pectin. Within 24 h after pectin oral administration the total energy intake did not differ from control. Insulin plasma level was 2.5 fold lower and ghrelin plasma concentration was 25% higher in the mice that received pectin compared to control, at the end of the 24 h SH access period. The administration of tansy pectin was found to decrease anxietyrelated behaviour in mice. Its administration significantly increased the time spent in the central sector of the open field apparatus by 87%, the time spent in the light area of the light-dark box by 31%, and the time spent on the open arms of the elevated plus maze by 22% compared with the control. Conclusion. Overall, tansy pectin reduced the binge eating of SH representing highly palatable, sweet, and fatty food. Reduced intake SH lead to a decrease in insulin concentration. Blood level of ghrelin was increased in mice treated with tansy pectin at the end of the sweet and fatty food presentation period. Tansy pectin reduced the level of anxiety in mice.

Clinical guidance for the use of trazodone in major depressive disorder and concomitant conditions: pharmacology and clinical practice.

AIM: To provide a review of the clinically relevant evidence pertaining to the use of trazodone in major depressive disorder. METHODS: Medline and Cochrane Library searches were searched using the keywords 'trazodone' AND 'depression', to identify the most relevant literature pertinent to the pharmacological properties of trazodone and its use in clinical practice. Articles that were selected included basic pharmacology papers, clinical trials, clinical practice guidelines, and reviews. Related references were cross checked. European and United States prescribing information was reviewed as well. An effort was made to give weight to the information that was most relevant for daily clinical practice. RESULTS: Trazodone is an antidepressant with a mechanism of action that remains innovative and with a favorable profile for the treatment of depression. The appropriate antidepressant doses are usually 150-300 mg/day and are often higher than the doses that are used when trazodone is prescribed to augment the antidepressant effect of another medication, for instance when trazodone is prescribed to address insomnia in a patient treated with an SSRI. Trazodone is usually well tolerated and has a low risk of anticholinergic side effects, weight gain and sexual side effects. DISCUSSION: Trazodone is an established medication that is efficacious for the treatment of a broad array of depressive symptoms, including symptoms that are less likely to respond to other antidepressants (e.g. SSRI), such as insomnia. As an antidepressant, trazodone has proven as efficacious as the tricyclic and second-generation antidepressants and is tolerated relatively well. Trazodone may be helpful for patients with major depression and comorbid insomnia, anxiety or psychomotor agitation. CONCLUSIONS: Trazodone is efficacious antidepressants with a relatively low risks of side effects such as weight gain, sexual or anticholinergic effects (such as constipation, urinary retention, dry mouth). In addition to being able to control a wide range of depressive symptoms, trazodone may improve sleep and be particularly helpful for patients whose symptoms of depression include insomnia.

The Effects of the Monoamine Stabilizer (-)-OSU6162 on Binge-Like Eating and Cue-Controlled Food-Seeking Behavior in Rats.

Binge-eating disorder (BED) is characterized by recurring episodes of excessive consumption of palatable food and an increased sensitivity to food cues. Patients with BED display an addiction-like symptomatology and the dopamine system might be a potential treatment target. The clinically safe monoamine stabilizer (-)-OSU6162 (OSU6162) restores dopaminergic dysfunction in long-term alcohol-drinking rats and shows promise as a novel treatment for alcohol use disorder. Here, the effects of OSU6162 on consummatory (binge-like eating) and appetitive (cue-controlled seeking) behavior motivated by chocolate-flavored sucrose pellets were evaluated in non-food-restricted male Lister Hooded rats. OSU6162 significantly reduced binge-like intake of chocolate-flavored sucrose pellets without affecting prior chow intake. Furthermore, OSU6162 significantly reduced the cue-controlled seeking of chocolate-flavored sucrose pellets under a second-order schedule of reinforcement before, but not after, the delivery and ingestion of reward, indicating a selective effect on incentive motivational processes. In contrast, the dopamine D2/D3 receptor antagonist raclopride reduced the seeking of chocolate-flavored sucrose pellets both pre- and post reward ingestion and also reduced responding under simpler schedules of seeking behavior. The D1/5 receptor antagonist SCH23390 had no effect on instrumental behavior under any reinforcement schedule tested. Finally, local administration of OSU6162 into the nucleus accumbens core, but not dorsolateral striatum, selectively reduced cue-controlled sucrose seeking. In conclusion, the present results show that OSU6162 reduces binge-like eating behavior and attenuates the impact of cues on seeking of palatable food. This indicates that OSU6162 might serve as a novel BED medication.

The Overlap Between Binge Eating Behaviors and Polycystic Ovarian Syndrome: An Etiological Integrative Model.

Studies indicate that Polycystic Ovarian Syndrome (PCOS) features (e.g. insulin instability, food cravings, overproduction of androgens and menstrual irregularities) are associated with increased appetite, impaired impulse control and feelings of body dissatisfaction. Counter intuitively, binge eating behaviors have been shown to reinforce PCOS symptomatology, precipitating concurrently body dissatisfaction, weight gain, insulin instability and overproduction of androgens. The present systematic literature review aspires to investigate the relationship between binge eating, in the broader context of eating disorder behaviors, and Polycystic Ovarian Syndrome (PCOS), taking into account shared characteristics between EDs (Eating Disorders) and PCOS. To address this aim, the PRISMA guidelines are adopted. A total of 21 studies, which investigated the presence of binge eating in PCOS population and the presence of PCOS in EDs population, were synthesized. Findings suggested that an increased prevalence of binge eating has been reported in women with Polycystic Ovarian Syndrome (PCOS); and that women suffering from BN (Bulimia Nervosa) and BED (Binge Eating Disorder) are more likely to display polycystic ovaries. Further research on their shared liability is required in order to inform more efficient prevention and treatment initiatives for populations presenting with comorbid features.

Dopamine and µ-opioid receptor dysregulation in the brains of binge-eating female rats - possible relevance in the psychopathology and treatment of binge-eating disorder.

Adult, female rats given irregular, limited access to chocolate develop binge-eating behaviour with normal bodyweight and compulsive/perseverative and impulsive behaviours similar to those in binge-eating disorder. We investigated whether (a) dysregulated central nervous system dopaminergic and opioidergic systems are part of the psychopathology of binge-eating and (b) these neurotransmitter systems may mediate the actions of drugs ameliorating binge-eating disorder psychopathology. Binge-eating produced a 39% reduction of striatal D1 receptors with 22% and 23% reductions in medial and lateral caudate putamen and a 22% increase of striatal µ-opioid receptors. There was no change in D1 receptor density in nucleus accumbens, medial prefrontal cortex or dorsolateral frontal cortex, striatal D2 receptors and dopamine reuptake transporter sites, or µ-opioid receptors in frontal cortex. There were no changes in ligand affinities. The concentrations of monoamines, metabolites and estimates of dopamine (dopamine/dihydroxyphenylacetic acid ratio) and serotonin/5-hydroxyindolacetic acid ratio turnover rates were unchanged in striatum and frontal cortex. However, turnover of dopamine and serotonin in the hypothalamus was increased ~20% and ~15%, respectively. Striatal transmission via D1 receptors is decreased in binge-eating rats while µ-opioid receptor signalling may be increased. These changes are consistent with the attenuation of binge-eating by lisdexamfetamine, which increases catecholaminergic neurotransmission, and nalmefene, a µ-opioid antagonist.

Investigation of impulsivity in binge-eating rats in a delay-discounting task and its prevention by the d-amphetamine prodrug, lisdexamfetamine.

Freely-fed, female, rats were trained in a two-lever, delay-discounting task: one lever delivered a single chocolate-flavoured pellet immediately and the other a three-pellet reward after increasing delay (0, 4, 8, 16, 32 s). Rats were divided into two groups (i.e. binge-eating rats given irregular, limited access to chocolate in addition to normal chow and controls maintained on normal chow). Both groups exhibited increased preference for the immediate reward as the delay interval was lengthened. The discounting rate was significantly greater in binge-eating rats than non-binge-eating controls, especially as the behaviour became more established indicating that increased impulsivity and intolerance of delayed reward are part of the psychopathology of binge-eating. Lisdexamfetamine (0.8 mg/kg, orally ( d-amphetamine base)) reversed the reduced preference of binge-eating rats for larger rewards at delay intervals of 4 s, 8 s and 32 s and across all sessions. Lisdexamfetamine-treated binge-eating rats consumed the same number of pellets as vehicle-treated, binge-eating rats and non-binge-eating controls eliminating the possibility lisdexamfetamine's actions on appetite or satiety mediated its effects on operant responding for food pellets in delay-discounting. In summary, binge-eating rats showed increased impulsive choice compared with non-binge-eating controls that was reversed by lisdexamfetamine, complementing results showing lisdexamfetamine reduced impulsiveness scores in patients with binge-eating disorder.

Binge eating and biochemical markers of appetite in new users of the contraceptive depot medroxyprogesterone acetate.

PURPOSE: Weight gain has been cited by women as one of the main reasons for discontinuation of the contraceptive depot medroxyprogesterone acetate (DMPA). This study aimed to evaluate binge eating and the biochemical markers of appetite in new DMPA users. METHODS: In this prospective non randomized study with adult healthy women, twenty-eight users of DMPA and twenty-five users of a copper intrauterine device (IUD) were paired for age (±1 year) and body mass index (BMI) (±1 kg/m2). We evaluated binge eating using the Binge Eating Scale (BES), the serum levels of neuropeptide Y, leptin and adiponectin, and the BMI at baseline and after 12 months in both groups. For statistical analysis was used ANOVA for to compare the means of the repeated measurements. RESULTS: Mean age was 29.6 and 28.6 years and BMI was 23.9 and 24.5 kg/m2 for the DMPA and IUD groups, respectively. After 12 months, the frequency of the scores of binge eating remained low in both groups. There were no significant differences between the groups at 12 months with respect to BMI, levels of NPY, leptin, adiponectin, and BES scores. CONCLUSIONS: Healthy adult women did not present with central stimulation of appetite or binge eating disorder in their first year after starting use of DMPA. This study reinforces the use of the contraceptive DPMA and the need for guidance related to living a healthy lifestyle for women who attribute the increase of body weight to the use of the method.

Lisdexamfetamine reduces the compulsive and perseverative behaviour of binge-eating rats in a novel food reward/punished responding conflict model.

Compulsive and perseverative behaviour in binge-eating, female, Wistar rats was investigated in a novel food reward/punished responding conflict model. Rats were trained to perform the conditioned avoidance response task. When proficient, the paradigm was altered to a food-associated conflict test by placing a chocolate-filled jar (empty jar for controls) in one compartment of the shuttle box. Entry into the compartment with the jar triggered the conditioning stimulus after a variable interval, and foot-shock 10 seconds later if the rat did not leave. Residence in the 'safe' compartment with no jar did not initiate trials or foot-shocks. By frequently entering the chocolate-paired compartment, binge-eating rats completed their 10 trials more quickly than non-binge controls. Binge-eating rats spent a greater percentage of the session in the chocolate-paired compartment, received foot-shocks more frequently, and tolerated foot-shocks for longer periods; all consistent with compulsive and perseverative behaviour. The d-amphetamine prodrug, lisdexamfetamine, has recently received US approval for the treatment of moderate to severe binge-eating disorder in adults. Lisdexamfetamine (0.8 mg/kg po [d-amphetamine base]) decreased chocolate consumption by binge-eating rats by 55% and markedly reduced compulsive and perseverative responding in the model. These findings complement clinical results showing lisdexamfetamine reduced compulsiveness scores in subjects with binge-eating disorder.