Depression-Related Increases and Decreases in Appetite: Dissociable Patterns of Aberrant Activity in Reward and Interoceptive Neurocircuitry

Altered food liking in depression is driven by macronutrient composition

Major depressive disorder (MDD) is characterized by changes in appetite and body weight as well as blunted reward sensitivity (‘anhedonia’). However, it is not well understood which mechanisms are driving changes in reward sensitivity, specifically regarding food. Here, we used a sample of 117 participants (54 patients with MDD and 63 healthy control participants [HCPs]) who completed a food cue reactivity task with ratings of wanting and liking for 60 food and 20 non-food items. To evaluate which components of the food may contribute to altered ratings in depression, we tested for associations with macronutrients of the depicted items. In line with previous studies, we found reduced ratings of food wanting (p = .003) but not liking (p = .23) in patients with MDD compared to matched HCPs. Adding macronutrient composition to the models of wanting and liking substantially improved their fit (ps < .001). Compared to carbohydrate-rich foods, patients with MDD reported lower liking and wanting ratings for high-fat and high-protein foods. Moreover, patients with MDD showed weaker correlations in their preferences for carbohydrate- versus fat- or protein-rich foods (ps < .001), pointing to potential disturbances in metabolic signaling. To conclude, our results suggest that depression-related alterations in food reward ratings are more specific to the macronutrient composition of the food than previously anticipated, hinting at disturbances in gut–brain signaling. These findings raise the intriguing question of whether interventions targeting the gut could help normalize aberrant reward signals for foods rich in fat or protein.

The impacts of antipsychotic medications on eating-related outcomes: A mixed methods systematic review

BACKGROUND

Almost all antipsychotics are associated with weight gain. Given the gravity of this side-effect and its consequences, it is imperative to understand the mechanisms involved. One mechanism that could contribute to this side effect is the impact of antipsychotics on eating-related outcomes.

OBJECTIVE

We aimed to synthesise the available quantitative research on the effects of first- and second-generation antipsychotics on eating-related outcomes, and qualitative research exploring people's experiences with these medications in relation to appetite and eating behaviours (PROSPERO protocol CRD42022340211).

METHODS

We searched Medline, PsycInfo, and Web of Science from inception to 9 May 2024. Quantitative data were synthesised without meta-analysis using vote counting based on direction of effect. Qualitative data were synthesised using thematic synthesis.

RESULTS

Searches identified 8,746 citations yielding 61 separate studies; 55 quantitative and 6 qualitative, published 1982-2024. Using GRADE, our assessment of the quantitative review findings ranged from low to very low-level certainty. Given the lack of direct evidence from high-quality placebo-controlled trials, it is pertinent to interpret the quantitative findings with caution. Using GRADE-CERQual, our assessment of the qualitative review findings ranged from low to very low-level certainty; these findings suggest that the relationship between antipsychotics and food intake is influenced by an interplay of individual, interpersonal and external factors, the most significant of which is food environment.

LIMITATIONS

The internal validity of this review was affected by the serious limitations of the included quantitative studies and the paucity of qualitative evidence.

STRENGTHS

We used GRADE and GRADE-CERQual frameworks to enhance the transparency of our judgement of the certainty of the evidence. Lived experience perspectives were incorporated in different stages of the review to enhance its relevance and practical implications.

CONCLUSIONS

There is insufficient evidence from well-conducted studies to determine the effect of antipsychotics on eating-related outcomes.

Role of the insula in rTMS response for depression

BACKGROUND

The insula has a significant impact on interoception and depression. This study aims to explore the role of the insula in mediating treatment responses to high-frequency repetitive transcranial magnetic stimulation (rTMS) targeting the left dorsolateral prefrontal cortex (DLPFC).

METHODS

Twenty-five patients with either bipolar disorder (BD, n = 15) or major depressive disorder (MDD, n = 10) were recruited. All subjects were aged between 20 and 70, with a minimum score of 18 on the 24-item Hamilton Rating Scale for Depression (HDRS-24). Each patient received 12 sessions of rTMS treatment using a figure-eight-shaped coil at 10 Hz high-frequency stimulation intensity, targeted to the left DLPFC. Resting-state functional magnetic resonance imaging was conducted before and after the rTMS treatment to assess changes in insula-seeded functional connectivity.

RESULTS

Both BD and MDD patients experienced significant reductions in depressive symptoms following rTMS therapy. The respective response rates at weeks 4, 8 and 12 were 64.0 %, 64.0 % and 68.0 % and remission rates were 40.0 %, 36.0 % and 44.0 %. Decreases in functional connectivity between the right anterior insula and right calcarine were significantly larger in the remitters than in the non-remitters (p = 0.013). Additionally, a higher baseline functional connectivity between the right anterior insula and right superior temporal gyrus correlated with better treatment outcome.

LIMITATIONS

The small sample size of 25 participants is small.

CONCLUSION

Our findings highlight the potential role of the insula in depression and suggest that insula-seeded functional connectivity could serve as a predictive biomarker for rTMS efficacy.

The moderating effect of frailty on the network of depression, anxiety, and loneliness in community-dwelling older adults

OBJECTIVES

Comorbidities of depression, anxiety and loneliness may be more prevalent in frail older adults, which may lead to an accelerated deterioration of psychological symptoms. This study was aimed to assess the moderating effect of frailty on the network of depression, anxiety, and loneliness symptoms in community-dwelling older adults.

METHODS

A sample of 4253 older adults were recruited from the Psychology and Behavior Investigation of Chinese Residents (PBICR). Frailty, depression, anxiety, and loneliness were assessed using the FRAIL scale, the Patient Health Questionnaire-9, the Generalized Anxiety Disorder 7-item scale, and the Three-Item Loneliness Scale, respectively. Covariates of age, gender, education level, living status, marital status, and monthly family income were also collected.

RESULTS

The prevalence of combined depression, anxiety and loneliness was 36.49 % in (pre)frail (i.e., frail or prefrail) older adults. Using the moderated network model, we found that (pre)frail older adults were more likely to experience "sad mood", "appetite changes", and "feel left out" than non-frail older adults. In addition, (pre)frail older adults had stronger correlations between "feel left out" and "feel isolated from others", "feel isolated from others" and "lack companionship", "nervousness or anxiety" and "feel left out", "nervousness or anxiety" and "feel isolated from others", and "sleep difficulties" and "feel left out" than non-frail older adults, while non-frail older adults had stronger correlations between "feel worthlessness" and "psychomotor agitation/retardation" than (pre)frail older adults.

CONCLUSIONS

(Pre)frail older adults may experience more comorbidities of depression, anxiety and loneliness due to more symptoms and stronger correlations between specific symptoms in the network. Future studies should target these symptoms to eliminate comorbidities of depression, anxiety and loneliness in (pre)frail older adults.

Neuroimaging aspects of interception in mood disorders: A systematic review

INTRODUCTION

Mood disorders often involve attenuated interoception, which impairs the accurate perception and interpretation of internal bodily signals. Functional magnetic resonance imaging has been used to explore the neurobiology of interoception in vivo while participants are performing interoceptive tasks.

AIM

The aim of this review is to present the progress in neuroimaging studies of interoception in mood disorders.

METHODS

We performed a systematic search in Pubmed, Scopus and Web of Science with the terms "interoception", "depression", "bipolar disorder", "mood disorders", "neuroimaging" and derivative terms.

RESULTS

461 records have been identified in the 3 databases, 34 records were assessed for eligibility and finally 17 reports were selected. The main findings were: disrupted cardioception in Major Depressive Disorder (MDD) which was related to reduced insular activity; altered visceroception in major depression has been linked to hypoactivation in the dorsal mid-insula; reduced nociception was reflected by hypoactivation in the insula in both MDD and Bipolar Disorder, and altered insular activity has been linked to maladaptive eating behavior.

DISCUSSION & CONCLUSION

The current review demonstrated that neuroimaging studies focusing on interoceptive tasks in mood disorders are limited in both number and sample size. This is notably relevant to bipolar disorder where only one publication was found. Nevertheless, we were able to outline the findings on four separate aspects of interoception - cardioception, visceroception, nociception and appetite all of which are pointing to the insula as core dysfunctional region. Further research is needed to draw more conclusive insights and improve our understanding of interoception in mood disorders.

Heterogeneous appetite patterns in depression: computational modeling of nutritional interoception, reward processing, and decision-making

Accurate interoceptive processing in decision-making is essential to maintain homeostasis and overall health. Disruptions in this process have been associated with various psychiatric conditions, including depression. Recent studies have focused on nutrient homeostatic dysregulation in depression for effective subtype classification and treatment. Neurophysiological studies have associated changes in appetite in depression with altered activation of the mesolimbic dopamine system and interoceptive regions, such as the insular cortex, suggesting that disruptions in reward processing and interoception drive changes in nutrient homeostasis and appetite. This study aimed to explore the potential of computational psychiatry in addressing these issues. Using a homeostatic reinforcement learning model formalizing the link between internal states and behavioral control, we investigated the mechanisms by which altered interoception affects homeostatic behavior and reward system activity via simulation experiments. Simulations of altered interoception demonstrated behaviors similar to those of depression subtypes, such as appetite dysregulation. Specifically, reduced interoception led to decreased reward system activity and increased punishment, mirroring the neuroimaging study findings of decreased appetite in depression. Conversely, increased interoception was associated with heightened reward activity and impaired goal-directed behavior, reflecting an increased appetite. Furthermore, effects of interoception manipulation were compared with traditional reinforcement learning parameters (e.g., inverse temperature β and delay discount γ), which represent cognitive-behavioral features of depression. The results suggest that disruptions in these parameters contribute to depressive symptoms by affecting the underlying homeostatic regulation. Overall, this study findings emphasize the importance of integrating interoception and homeostasis into decision-making frameworks to enhance subtype classification and facilitate the development of effective therapeutic strategies.

A study on the effects of metacinnabar (β-HgS) on weight and appetite recovery in stressed mice

ETHNOPHARMACOLOGICAL RELEVANCE

Depression is a prevalent stress disorder, yet the underlying physiological mechanisms linking stress to appetite and weight loss remain elusive. While most antidepressants are associated with excessive weight and appetite gain, sertraline (SER) exhibits a lower risk of these side effects. Metacinnabar (β-HgS), the primary component of Tibetan medicine Zuotai, has been shown to enhance mice's resilience against external stress without causing excessive increases in weight or appetite. However, the precise physiological pathway through which β-HgS restores appetite and weight in stressed mice remains unclear.

AIM OF THE STUDY

The objective of this study is to assess the efficacy of β-HgS in ameliorating weight loss and appetite suppression induced by pressure stimulation in mice, as well as elucidate its potential mechanisms of action.

METHODS

The present study employed chronic restraint stress (CRS) and chronic unpredictable mild stress (CUMS) as experimental models to simulate environmental stress encountered in daily life. Subsequently, a series of experiments were conducted, including behavior tests, HE staining of rectal and hippocampal pathological sections, detection of depression-related biological indicators, analysis of intestinal flora diversity, as well as metabolomics analysis of hippocampal and intestinal contents.

RESULT

Dysregulation of glycerophospholipid metabolism may represent the principal pathway underlying reduced appetite, body weight, neurotransmitter and appetite hormone levels, heightened inflammatory response, hippocampal and rectal tissue damage, as well as altered composition of intestinal microbiota in stressed mice. Following intervention with SER and β-HgS in stressed mice, the deleterious effects induced by stress can be ameliorated, in which the medium-dose β-HgS exhibited superior performance.

CONCLUSION

The aforementioned research findings suggest that the stress-induced decrease in appetite and body weight in mice may be associated with dysregulation in glycerophospholipid metabolism connecting the gut-brain axis. β-HgS exhibits potential in ameliorating depressive-like symptoms in mice subjected to stress, while concurrently restoring their body weight and appetite without inducing excessive augmentation. Its therapeutic effect may also be attributed to its ability to modulate glycerophospholipid metabolism status and exert influence on the gut-brain axis.

The differential orbitofrontal activity and connectivity between atypical and typical major depressive disorder

OBJECTIVE

Atypical major depressive disorder (MDD) is a distinct subtype of MDD, characterized by increased appetite and/or weight gain, excessive sleep, leaden paralysis, and interpersonal rejection sensitivity. Delineating different neural circuits associated with atypical and typical MDD would better inform clinical personalized interventions.

METHODS

Using resting-state fMRI, we investigated the voxel-level regional homogeneity (ReHo) and functional connectivity (FC) in 55 patients with atypical MDD, 51 patients with typical MDD, and 49 healthy controls (HCs). Support vector machine (SVM) approaches were applied to examine the validity of the findings in distinguishing the two types of MDD.

RESULTS

Compared to patients with typical MDD and HCs, patients with atypical MDD had increased ReHo values in the right lateral orbitofrontal cortex (OFC) and enhanced FC between the right lateral OFC and right dorsolateral prefrontal cortex (dlPFC), and between the right striatum and left OFC. The ReHo in the right lateral OFC and the significant FCs found were significantly correlated with body mass index (BMI) in all groups of participants with MDD. The connectivity of the right striatum and left OFC was positively correlated with the retardation scores in the atypical MDD group. Using the ReHo of the right lateral OFC as a feature, we achieved 76.42% accuracy to differentiate atypical MDD from typical MDD.

CONCLUSION

Our findings show that atypical MDD might be associated with altered OFC activity and connectivity. Furthermore, our findings highlight the key role of lateral OFC in atypical MDD, which may provide valuable information for future personalized interventions.

A Systematic Review Exploring Dietary Behaviors, Psychological Determinants and Lifestyle Factors Associated with Weight Regain After Bariatric Surgery

BACKGROUND

Weight regains after bariatric surgery presents a significant challenge to long-term weight management and overall health outcomes. While clinical and surgical factors influencing bariatric outcomes have been extensively reviewed, there remains a notable gap in understanding how behavioral factors-specifically dietary habits, psychological influences, and lifestyle choices-impact long-term weight maintenance. This systematic review addresses this gap, highlighting the unique role of these behavioral factors in sustaining weight loss post-bariatric surgery.

AIM

This systematic review aims to explore the behavioral factors-including dietary, psychological, and lifestyle influences-associated with weight regain after bariatric surgery.

METHODS

A comprehensive search was conducted across multiple databases, focusing on peer-reviewed articles published in English. We included observational studies exclusively focused on adults who experienced weight regain after bariatric surgery, with an emphasis on behavioral factors. Searches were conducted in MEDLINE via PubMed, Embase, Web of Science, Scopus, and Google Scholar, with the last search completed on 10 July 2024. Studies published within the past 10 years were considered. The Joanna Briggs Institute (JBI) critical appraisal tool for cross-sectional studies was used to assess the risk of bias. A total of 16 studies met the inclusion criteria: 12 cross-sectional studies, 3 cohort studies, and 1 in-depth interview study.

RESULTS

The review found inconsistencies in the definitions of weight regain across studies. Nonetheless, three primary behavioral factors were identified as potentially contributing to weight regain: dietary non-adherence and eating patterns, psychological determinants, and lifestyle behaviors. Dietary non-adherence included high-calorie food consumption, excessive intake of sweets, carbohydrates, and sweetened beverages, and low protein intake. Psychological factors such as depression, anxiety, emotional eating, and binge eating were prevalent among individuals experiencing weight regain. Lifestyle behaviors, including physical inactivity, smoking, and sedentary habits, also played significant roles.

CONCLUSIONS

Post-bariatric weight management is multifaceted, necessitating a comprehensive approach that addresses dietary, psychological, and lifestyle factors. Most studies on behavioral factors linked to weight regain were cross-sectional with small sample sizes, limiting the ability to infer causality. Future research should include detailed information on dietary adherence, standardized tools to assess physical activity and sedentary behavior, and validated measures for psychological health. Tailored interventions and continuous support from healthcare professionals are essential for maximizing the effectiveness of bariatric surgery, promoting sustainable weight loss, and enhancing overall health outcomes.

Divergent transcriptomic profiles in depressed individuals with hyper- and hypophagia implicating inflammatory status

BACKGROUND

Major Depressive Disorder (MDD) is a heterogenous and etiologically complex disease often presenting with divergent appetitive phenotypes including Hyperphagic MDD (characterized by an increased appetite) and Hypophagic MDD (characterized by a decrease in appetite) which are closely related to comorbidities, including cardiometabolic disorders. Hyperphagia is associated with atypical depression, decreased stress-hormone signaling, a pro-inflammatory status, hypersomnia, and poorer clinical outcomes. Yet, our understanding of associated biological correlates of Hyperphagic and Hypophagic MDD remain fragmented.

METHODS

We performed an exploratory study on peripheral blood RNA profiling using bulk RNAseq in unmedicated individuals with Hyperphagic and Hypophagic MDD (n = 7 and n = 13, respectively).

RESULTS

At baseline, we discovered an increased expression of TADA2B in hyperphagic MDD with the significant enrichment of 72 gene ontology pathways mainly related to inflammation. In addition, we used the Maastricht Acute Stress Task to uncover stress-related transcriptomic profiles in Hyper- and Hypophagic MDD and discovered the upregulation of CCDC196 and the downregulation of SPATA33 in hyperphagic MDD. Gene ontology enrichment analysis after stress exposure showed pathways related to ribosomal activity.

LIMITATIONS

The present findings are tempered primarily by the limited sample size, which requires independent replication of this exploratory study. However, stringent methods controlling for false positive findings mitigate the risk associated with sample size limitations.

DISCUSSION

Limitations notwithstanding, findings suggest that hyper- and hypophagic MDD is associated with divergent RNA expression profiles in peripheral blood that are amplified by exposure to a controlled stress test. Our findings in a well-controlled study provide evidence for peripheral markers of a relevant endophenotype of MDD.

Association between triglyceride and depression: A systematic review and meta-analysis

Depression is accompanied by dyslipidemia, which may increase the risk of stroke and coronary heart disease. This study sought to quantitatively summarize the clinical data comparing peripheral blood triglyceride (TG) concentrations between patients with major depressive disorder (MDD) and healthy controls (HCs). Studies were searched in PubMed, EMBASE, PsycINFO, and Cochrane Databases up to March 2023. We also reviewed the reference lists of obtained articles. Mean (±SD) for TG concentrations were extracted, combined quantitatively using random-effects meta-analysis, and summarized as a standardized mean difference (SMD). Subgroup analysis and meta-regression was performed to explore the resource of heterogeneity. Thirty-eight studies measuring the concentrations of peripheral blood TG in 2604 patients with MDD and 3272 HCs were included. Meta-analysis results indicated that TG levels were significant higher in patients with MDD than in HCs (SMD = 0.31, 95% confidence interval [CI]: 0.16 to 0.46, Z46 = 4.05, p < 0.01). Heterogeneity was detected (χ2 = 269.97, p < 0.01, I2 = 85%). Subgroup analysis demonstrated significant differences in TG levels between patients with MDD and HCs depended on age, body mass index and drug use (p < 0.05), but no differences between groups. Meta-regression also found no significant variables. TG level was significantly elevated in depression, which may explain the increased risk of cardiovascular and cerebrovascular events in depression.

NSAID medication mediates the causal effect of genetically predicted major depressive disorder on falls: Evidence from a Mendelian randomization study

BACKGROUND

Increasing evidence supports that depression including major depressive disorder (MDD) is associated with an increased risk of falls. However, some studies suggest no association between MDD and falls. Therefore, the specific causal relationship whereby MDD affects the risk of falls remains elusive, and the potential mediators are unclear.

METHODS

Summary-level data for MDD and falls were collected from the Genome-wide association studies (GWAS) in this study. Mendelian randomization (MR) and multivariable MR (MVMR) analyses were performed to evaluate the causal associations between MDD and falls. A Two-step MR analysis was employed to analyze the mediating effect of nonsteroidal anti-inflammatory drugs (NSAIDs) on the causal association between MDD and the risk of falls.

RESULTS

Using the inverse-variance weighted (IVW) method, genetically predicted MDD was associated with an increased risk of falls (β = 0.15, SE = 0.034; P = 1.61E-5). MVMR and two-step MR analyses demonstrated that MDD was a causal determinant of increased falls independent of body mass index (BMI), smoking initiation, and alcohol consumption and that this causal relationship was mediated by NSAID medication.

LIMITATIONS

Extracted GWAS summary statistics are from European ancestry. Stratified analyses by sex and age were not included in our study. Therefore, it is unclear whether the results are the same for other ethnic groups, genders, and ages.

CONCLUSIONS

Our results demonstrate that MDD is independently associated with an increased risk of falls, in which NSAIDs mediate the association. This study suggests that avoiding the use of NSAIDs may reduce the risk of falls in patients diagnosed with MDD.

Beyond medications: a multifaceted approach to alleviating comorbid anxiety and depression in clinical settings

Background

Comorbid anxiety and depression are common and can make the problems more complex and sometimes resistant to pharmacological treatment. In existing research, the diagnoses are often studied separately, and physical activity, healthy nutrition, psychoeducation, and social support have shown good effects. The aim of the present study was to explore the longitudinal effects of a comprehensive treatment on patients with comorbid anxiety and depression in a clinical context.

Method

Eighty inpatients (15 men and 65 women) in age range 23-65 years receiving psychiatric treatment in Norwegian clinic participated in the longitudinal study. Treatment was person-centered and was most frequently given for anxiety and depression, e.g., pharmacological treatment and psychotherapy, individually and in groups. In combination with this, physical activity, healthy nutrition, psychoeducation and social support in contacts with authorities and relatives were also a part of treatment. Depression and anxiety were assessed using the Beck Anxiety Inventory and Beck Depression Inventory at three points in time: baseline, at the end of treatment, and 3 months after treatment. The answers were categorized and combined into four groups according to severity of anxiety and depression to measure effects on comorbidity. Mann Whitney U test, Chi-square, Friedmans test, and McNemar test were used to analyze the data.

Result

The results showed a significant increase of frequencies in the group with mild anxiety and depression 3 months past treatment compared to baseline.

Conclusion

Through the comprehensive, person-centered treatment more patients had low levels of both anxiety and depression 3 months after treatment. We suggest that clinics working with comorbid depression and anxiety patients should add physical activity, nutrition advice, social support, and psychoeducation to the traditional treatment regimes. More research concerning comorbid anxiety and depression are urgent to further expand the treatment possibilities.

Loneliness as a moderator of the association of affective symptoms and binge eating among college women

Affective symptoms (e.g., depression, anxiety, shame) are a potent risk factor for binge eating. However, less is known on the role of loneliness as a moderator of affective symptoms and binge eating. This objective of the current study was to investigate main effects and interactions of affective symptoms and loneliness in relation to binge eating in college women. A sample of 556 undergraduate women completed self-report questionnaires of affective symptoms, loneliness, and binge eating. Results revealed significant interactions between each affective symptom variable and loneliness in relation to binge eating, such that loneliness strengthened the positive association of affective symptoms and greater binge eating. The findings of this study demonstrate an important role of loneliness to binge eating among college women, especially those with underlying affective vulnerabilities. More theoretical and treatment-oriented work on the role of loneliness in binge eating is needed to understand mechanisms and interventions/preventions.

Reserpine-induced rat model for depression: Behavioral, physiological and PET-based dopamine receptor availability validation

BACKGROUND

Reserpine (RES), a Vesicular Monoamine Transporter 2 (VMAT2) inhibitor agent, has been used in preclinical research for many years to create animal models for depression and to test experimental antidepressant strategies. Nevertheless, evidence of the potential use and validity of RES as a chronic pharmacological model for depression is lacking, and there are no comprehensive studies of the behavioral effects in conjunction with molecular outcomes.

METHODS

Experiment 1. Following baseline behavior testing sensitive to depression-like phenotype and locomotion (Phase 1), 27 Sprague-Dawley (SD) rats received i.p. either vehicle solution (0.0 mg/kg), low (0.2 mg/kg) or high (0.8 mg/kg) RES dose for 20 days using a pre-determined schedule and reassessed for behavioral phenotypes (Phase 2). After 10 days washout period, and a final behavioral assessment (Phase 3), the brains were collected 16 days after the last injection for mRNA-expression assessment. Experiment 2. In a similar timetable as in Experiment 1 but without the behavioral testing, 12 SD rats underwent repetitive dopamine D2/3 receptor PET scanning with [18F]DMFP following each Phase. The binding potential (BPND) of [18F]DMFP was quantified by kinetic analysis as a marker of striatal D2/3R availability. Weight and welfare were monitored throughout the study.

RESULTS

Significant, dose-dependent weight loss and behavioral deficits including both motor (hypo-locomotion) and non-motor behavior (anhedonia, mild anxiety and reduced exploration) were found for both the low and high dose groups with significant decrease in D2R mRNA expression in the accumbal region for the low RES group after Phase 3. Both RES treated groups showed substantial increase in [18F]DMFP BPND (in line with dopamine depletion) during Phase 2 and 3 compared to baseline and Controls.

CONCLUSIONS

The longitudinal design of the study demonstrated that chronic RES administration induced striatal dopamine depletion that persisted even after the wash-out period. However, the behavior phenotype observed were transient. The data suggest that RES administration can induce a rodent model for depression with mild face validity.

Neurobehavioral and molecular changes in a rodent model of ACTH-induced HPA axis dysfunction

Hypothalamic-pituitary-adrenal (HPA) axis dysregulation is linked to the pathophysiology of depression. Although exogenous adrenocorticotropic hormone (ACTH) is associated with a depressive-like phenotype in rodents, comprehensive neurobehavioral and mechanistic evidence to support these findings are limited. Sprague-Dawley rats (male, n = 30; female, n = 10) were randomly assigned to the control (male, n = 10) or ACTH (male, n = 20; female n = 10) groups that received saline (0.1 ml, sc.) or ACTH (100 μg/day, sc.), respectively, for two weeks. Thereafter, rats in the ACTH group were subdivided to receive ACTH plus saline (ACTH_S; male, n = 10; female, n = 5; 0.2 ml, ip.) or ACTH plus imipramine (ACTH_I; male, n = 10; female, n = 5;10 mg/kg, ip.) for a further four weeks. Neurobehavioral changes were assessed using the forced swim test (FST), the sucrose preference test (SPT), and the open field test (OFT). Following termination, the brain regional mRNA expression of BDNF and CREB was determined using RT-PCR. After two-weeks, ACTH administration significantly increased immobility in the FST (p = 0.03), decreased interaction with the center of the OFT (p < 0.01), and increased sucrose consumption (p = 0.03) in male, but not female rats. ACTH administration significantly increased the expression of BDNF in the hippocampus and CREB in all brain regions in males (p < 0.05), but not in female rats. Imipramine treatment did not ameliorate these ACTH-induced neurobehavioral or molecular changes. In conclusion, ACTH administration resulted in a sex-specific onset of depressive-like symptoms and changes in brain regional expression of neurotrophic factors. These results suggest sex-specific mechanisms underlying the development of depressive-like behavior in a model of ACTH-induced HPA axis dysregulation.

Ghrelin is associated with an elevated mood after an overnight fast in depression

BACKGROUND

Major depressive disorder (MDD) comprises subtypes with distinct symptom profiles. For example, patients with melancholic and atypical MDD differ in the direction of appetite and body weight changes as well as mood reactivity. Despite reported links to altered energy metabolism, the role of circulating neuropeptides from the gut in modulating such symptoms remains largely elusive.

METHODS

We collected data from 103 participants, including 52 patients with MDD and 51 healthy control participants (HCP). After an overnight fast, we measured plasma levels of (acyl and des-acyl) ghrelin and participants reported their current metabolic and mood states using visual analog scales (VAS). Furthermore, they completed symptom-related questionnaires (i.e., STAI-T).

RESULTS

Patients with atypical versus melancholic MDD reported less negative affect (p = 0.025). Higher levels of acyl ghrelin (corrected for BMI) were associated with improved mood (p = 0.012), specifically in patients with MDD. These associations of ghrelin were not mood-item specific and exceeded correlations with trait markers of negative affectivity. In contrast to associations with mood state, higher levels of ghrelin were not associated with increased hunger per se or changes in appetite in patients with MDD.

LIMITATIONS

The study is limited by the cross-sectional design without an intervention.

CONCLUSIONS

Our results reveal potentially mood-enhancing effects of ghrelin in fasting individuals that exceed associations with metabolic state ratings. These associations with circulating neuropeptides might help explain anti-depressive effects of fasting interventions and could complement conventional treatments in patients with melancholic MDD.

Non-invasive vagus nerve stimulation conditions increased invigoration and wanting in depression

BACKGROUND

Major depressive disorder (MDD) is often marked by impaired motivation and reward processing, known as anhedonia. Many patients do not respond to first-line treatments, and improvements in motivation can be slow, creating an urgent need for rapid interventions. Recently, we demonstrated that transcutaneous auricular vagus nerve stimulation (taVNS) acutely boosts effort invigoration in healthy participants, but its effects on depression remain unclear.

OBJECTIVE

To assess the impact of taVNS on effort invigoration and maintenance in a sample that includes patients with MDD, evaluating the generalizability of our findings.

METHODS

We used a single-blind, randomized crossover design in 30 patients with MDD and 29 matched (age, sex, and BMI) healthy control participants (HCP).

RESULTS

Consistent with prior findings, taVNS increased effort invigoration for rewards in both groups during Session 1 (p = .040), particularly for less wanted rewards in HCP (pboot < 0.001). However, invigoration remained elevated in all participants, and no acute changes were observed in Session 2 (Δinvigoration = 3.3, p = .12). Crucially, throughout Session 1, we found taVNS-induced increases in effort invigoration (pboot = 0.008) and wanting (pboot = 0.010) in patients with MDD, with gains in wanting maintained across sessions (Δwanting = 0.06, p = .97).

CONCLUSIONS

Our study replicates the invigorating effects of taVNS in Session 1 and reveals its generalizability to depression. Furthermore, we expand upon previous research by showing taVNS-induced conditioning effects on invigoration and wanting within Session 1 in patients that were largely sustained. While enduring motivational improvements present challenges for crossover designs, they are highly desirable in interventions and warrant further follow-up research.

The relationship between childhood psychological abuse and depression in college students: a moderated mediation model

BACKGROUND

Childhood psychological abuse (CPA) are highly correlated with depression among college students, but the underlying mechanisms between variables need further exploration. This study aims to investigate internet addiction as a mediating factor and alexithymia as a moderating factor, in order to further elucidate the potential risk factors between CPA and depression among college students.

METHODS

A self-report survey was conducted among 1196 college students from four universities in three provinces in China. The survey included measures of CPA, internet addiction, alexithymia, and depression. Descriptive and correlational analyses were performed on these variables, and a moderated mediation model was constructed.

RESULTS

CPA was positively correlated with depression among college students, as well as internet addiction with alexithymia. Internet addiction partially mediated the relationship between CPA and depression among college students, while alexithymia strengthened the relationships among the paths in the moderated mediation model.

CONCLUSION

This study provides further insights into the psychological mechanisms underlying the relationship between CPA and depression among college students. Internet addiction serves as a mediating factor in this relationship, while alexithymia may enhance the strength of the relationships among the three variables.

Prevention, Assessment, and Management of Malnutrition in Older Adults with Early Stages of Cognitive Disorders

Malnutrition is common in older adults, and its risk is greater in those living with dementia. Relative to cognitively healthy peers, the prevalence of malnutrition is also increased in individuals with early stages of cognitive disorders owing to pathophysiological, cognitive, and psychosocial changes related to cognitive impairment. Malnutrition is associated with adverse health outcomes, including faster cognitive and functional decline. Here, we provide an overview of the prevention, assessment, and management of malnutrition in older adults, with a special focus on the aspects that are important to consider in individuals with early stages of cognitive disorders. Strategies to prevent malnutrition include systematic screening for malnourishment using validated tools to detect those at risk. If the screening reveals an increased risk of malnutrition, a detailed assessment including the individual's nutritional, medical, and functional status as well as dietary intake should be performed. The management of malnutrition in the early stages of cognitive disorders should be based on the findings of a comprehensive assessment and be personalized according to the individual's specific characteristics. In the article, we also provide an overview of the evidence on vitamin supplements and specific dietary patterns to prevent cognitive decline or attenuate its progression.

Association between Dietary Antioxidant Capacity in Midlife and Depressive Symptoms in Late Life: The Singapore Chinese Health Study

Preclinical and limited epidemiological studies suggest that oxidative stress may be implicated in geriatric depression. Our study investigated the association between midlife dietary total antioxidant capacity (TAC) and depressive symptoms in late life among 13,712 participants in a population-based cohort of Chinese in Singapore. At baseline (1993-1998), intake of antioxidants from diet and supplements at a mean age of 52.4 years was estimated using a validated food frequency questionnaire to derive two dietary TAC indices from vitamins C and E, carotenoids and flavonoids: the Comprehensive Dietary Antioxidant Index (CDAI) and Vitamin C Equivalent Antioxidant Capacity (VCEAC). At follow-up 3 (2014-2016), when participants were at a mean age of 72.5 years, depressive symptoms were assessed using the Geriatric Depression Scale, and depression, defined as having ≥5 symptoms, was presented in 3173 (23.1%) participants. Both CDAI and VCEAC indices were inversely associated with odds of depressive symptoms in a stepwise manner: the OR (95% CI) comparing the extreme quartiles was 0.73 (0.64-0.83; Ptrend < 0.01) for the CDAI and 0.77 (0.68-0.87; Ptrend < 0.01) for the VCEAC. Specifically, higher intakes of vitamin C, carotenoids, and flavonoids were associated with a lower likelihood of depressive symptoms. Our findings support the recommendation of an antioxidant-rich diet for the prevention of depression.

A qualitative investigation of the Montgomery-Åsberg depression rating scale: discrepancies in rater perceptions and data trends in remote assessments of rapid-acting antidepressants in treatment resistant depression

Introduction

Despite the development of many successful pharmaceutical interventions, a significant subset of patients experience treatment-resistant depression (TRD). Ketamine and its derivatives constitute a novel therapeutic approach to treat TRD; however, standard tools, such as the Montgomery-Åsberg Depression Rating Scale (MADRS) are still being used to measure symptoms and track changes.

Methods

The aim of this study was to review item-level differences between rate of data change (MADRS score) and rater-weighted perception of the most useful items for assessing change in symptoms while remotely conducting the 10-item version of the MADRS in TRD in a clinical trial of rapid-acting antidepressants. Two studies of rapid-acting antidepressants in the treatment of TRD were used to identify item-scoring trends when MADRS is administered remotely and repeatedly (733 subjects across 10 visits). Scoring trends were evaluated in tandem to a rater survey completed by 75 raters. This was completed to gain insight on MADRS items' perceived level of helpfulness when assessing change of symptoms in rapid-acting antidepressant trials.

Results

MADRS items 'Reduced sleep', 'Apparent sadness', and 'Pessimistic thoughts' were found to have the greatest average data change by visit, while raters ranked 'Reported sadness', 'Lassitude' and 'Apparent sadness' as the most helpful items when assessing symptom change.

Discussion

The diversion between rate of data-change ranking and rater perception of helpfulness could be related to difficulty in assessing specific items, to the novel treatment itself, and/or to the sensitivity to symptom change to which raters are accustomed in traditional antidepressant treatments.

Mechanisms Involved in the Link between Depression, Antidepressant Treatment, and Associated Weight Change

Major depressive disorder is a severe mood disorder associated with a marked decrease in quality of life and social functioning, accompanied by a risk of suicidal behavior. Therefore, seeking out and adhering to effective treatment is of great personal and society-wide importance. Weight changes associated with antidepressant therapy are often cited as the reason for treatment withdrawal and thus are an important topic of interest. There indeed exists a significant mechanistic overlap between depression, antidepressant treatment, and the regulation of appetite and body weight. The suggested pathomechanisms include the abnormal functioning of the homeostatic (mostly humoral) and hedonic (mostly dopaminergic) circuits of appetite regulation, as well as causing neuromorphological and neurophysiological changes underlying the development of depressive disorder. However, this issue is still extensively discussed. This review aims to summarize mechanisms linked to depression and antidepressant therapy in the context of weight change.

Changes of structural functional connectivity coupling and its correlations with cognitive function in patients with major depressive disorder

BACKGROUND

Previous neuroimaging studies have reported structural and functional brain abnormalities in major depressive disorder (MDD). This study aimed to explore whether the coherence of structural-functional networks was affected by disease and investigate its correlation with clinical manifestations.

METHODS

The severity of symptoms and cognitive function of 121 MDD patients and 139 healthy controls (HC) were assessed, and imaging data, including diffusion tensor imaging, T1 structural magnetic resonance imaging (MRI) and resting-state functional MRI, were collected. Spearman correlation coefficients of Kullback-Leibler similarity (KLS), fiber number (FN), fractional anisotropy (FA) and functional connectivity (FC) were calculated as coupling coefficients. Double-weight median correlation analysis was conducted to investigate the correlations between differences in brain networks and clinical assessments.

RESULTS

The percentage of total correct response of delayed matching to sample and the percentage of delayed correct response of pattern recognition memory was lower in MDD. Compared with the HC, KLS-FC coupling between the parietal lobe and subcortical area, FA-FC coupling between the temporal and parietal lobe, and FN-FC coupling in the frontal lobe was lower in MDD. Several correlations between structural-functional connectivity and clinical manifestations were identified.

LIMITATIONS

First, our study lacks longitudinal follow-up data. Second, the sample size was relatively small. Moreover, we only used the Anatomical Automatic Labeling template to construct the brain network. Finally, the validation of the causal relationship of neuroimaging-behavior factors was still insufficient.

CONCLUSIONS

The alternation in structural-functional coupling were related to clinical characterization and might be involved in the neuropathology of depression.

Naturalistic food categories are driven by subjective estimates rather than objective measures of food qualities

Food-related studies often categorize foods using criteria such as fat and sugar content (e.g., high-fat, high-sugar foods; low-fat, low-sugar foods), and use these categorizations for further analyses. While these criteria are relevant to nutritional health, it is unclear whether they agree with the ways in which we typically group foods. Do these objective categories correspond to our subjective sense? To address this question, we recruited a group of 487 online participants to perform a triplet comparison task involving implicit object similarity judgements on images of 36 foods, which varied in their levels of fat and sugar. We also acquired subjective ratings of other food properties from another set of 369 online participants. Data from the online triplet task was used to generate a similarity matrix of these 36 foods. Principal Components Analysis (PCA) of this matrix identified that the strongest determinant of food similarity (the first PC) was most highly related to participants' judgements of how processed the foods were, while the second component was most related to estimates of sugar and fat content. K-means clustering analysis revealed five emergent food groupings along these PC axes: sweets, fats, starches, fruits, and vegetables. Our results suggest that naturalistic categorizations of food are driven primarily by knowledge of the origin of foods (i.e., grown or manufactured), rather than by their sensory or macronutrient properties. These differences should be considered and explored when developing methods for scientific food studies.

Emotional Eating and Cardiovascular Risk Factors in the Police Force: The Carolina Blue Project

There is an association between emotional eating and cardiovascular disease (CVD) risk factors; however, little is known about this association in the police force. This study explores the associations between emotional eating and CVD risk factors in law enforcement officers in North Carolina. Four hundred and five officers completed The Emotional Eating Scale, and 221 of them completed the assessment for CVD-related markers. Descriptive statistics, Pearson's correlation, and multiple linear regression analyses were performed. Emotional eating in response to anger was significantly positively associated with body weight (β = 1.51, t = 2.07, p = 0.04), diastolic blood pressure (β = 0.83, t = 2.18, p = 0.03), and mean arterial pressure (β = 0.84, t = 2.19, p = 0.03) after adjusting for age and use of blood pressure medicine. Emotional eating in response to depression was significantly positively associated with triglycerides (β = 5.28, t = 2.49, p = 0.02), while the emotional eating in response to anxiety was significantly negatively associated with triglycerides (β = -11.42, t = -2.64, p = 0.01), after adjusting for age and use of cholesterol medicine. Our findings offer new insights to address emotional eating and lower CVD risk in law enforcement officers.

Impact of weight loss for depressive symptom in mid-stage patients with Parkinson's disease: a 4-year follow-up study

Introduction

Weight loss is one of the non-motor symptoms frequently seen in patients with Parkinson's disease (PwPD). Weight loss in PwPD is known to be negatively associated with motor and other non-motor symptoms and has been shown to influence the prognosis of PD. In this study, we followed weight change over a 4-year period in PwPD at a single institution and investigated the relationship between weight change and patients' motor and non-motor symptoms.

Methods

PwPD who visited our hospital from January 2018 to December 2022 were enrolled. Body weights were measured at two points in 2018 (at the start of observation, 'baseline') and 2022 (at the end of observation, 'end date'). In addition, motor symptoms, disease severity, cognitive function, and psychiatric symptoms were evaluated during the same period, and the relationship with weight loss was examined.

Results

Data of 96 PwPD were available for a 4-year follow-up. At baseline, the mean age was 65.7 ± 10.0 years, the mean disease duration was 6.8 ± 4.0 years, and the mean Hoehn and Yahr stage was 2.4 ± 0.7. Among them, 48 patients (50.0%) had a weight loss of ≥5% from baseline (weight loss group; mean loss was 6.6 ± 2.9 kg). The weight loss group was older (p = 0.031), had a lower Mini-Mental State Examination (MMSE) at baseline (p = 0.019), a significantly lower body mass index (p < 0.001), and a higher Zung Self-Rating Depression Scale (SDS) (p = 0.017) at the end date. There was a negative correlation (γ = -0.349, p < 0.001) between weight change and age, a positive correlation (γ = 0.308, p = 0.002) between weight change and MMSE at baseline, and a negative correlation (γ = -0.353, p < 0.001) between weight change and SDS at the end date. Age-adjusted correlations showed a final negative correlation (γ = -0.331, p = 0.001) between weight change and SDS. MMSE and age-adjusted correlations showed a low negative correlation (γ = -0.333, p = 0.001) between weight change and SDS at the end date.

Conclusion

Weight loss in PwPD in mid-stage was more likely with increasing age, and ≥ 5% weight loss was associated with worsening depression. Further research is needed regarding the significance of weight loss in PwPD.

Perinatal dietary patterns and symptomatic depression: A prospective cohort study

To promote maternal and infant health, there is a need to optimise the dietary pattern of pregnant women to reduce perinatal depression. This prospective cohort study was conducted from June 2020 to February 2022, 300 women from a medical center were interviewed during late pregnancy and at 4-6 weeks postpartum. Dietary patterns were derived by factor analysis using a semiquantitative food frequency questionnaire. Symptomatic depression was defined using the Edinburgh Postpartum Depression Scale (EPDS, ranged 0-30). Their dairy, vegetable and fruit intakes were below the Taiwanese recommendations for pregnant women. Symptomatic depression (EPDS ≥10) affected 31.3% in the third trimester and 35.7% postpartum. Pre- and post-EPDS scores were positively correlated (r = 0.386, p < 0.001). Approximately 55% of those depressed before delivery were also depressed postpartum. For late pregnancy, four dietary patterns were identified ('Good oil', 'Vegetables and fruits', 'Omnivorous' and 'Refined-grain and organ meats'). Dietary patterns were classified according to quartiles (Q). Higher omnivorous pattern scores reduced the risk of depression. For prenatal depression, with Q1 as a reference, the risk was reduced by 38% for Q2, 43% for Q3 and 59% for Q4 (p for trend = 0.068). These findings became evident postpartum (reduced risk by 68% for Q2, 69% for Q3 and 70% for Q4 (p = 0.031; p for trend = 0.0032). The association between dietary patterns and depression encourages the routine nutritional management of pregnant women.

Protocol for a Pilot Study on the Neurocardiac Mechanism of an Interoceptive Compassion-Based Heart-Smile Training for Depression

Background

Heart-Smile Training (HST) is an interoceptive compassion-based behavioral intervention that in case reports has been beneficial for depression. Interoception refers to the awareness and regulation of physiological signals from inside the body. Depressed patients often have diminished interoceptive awareness and often experience disconnection from bodily needs and sensations. In addition to interoceptive dysfunction, depression often involves negative self-evaluation and self-critical rumination. HST is a compassion-based meditation training program that explicitly cultivates interoceptive awareness of the heart area. This study aims to investigate the possible neurocardiac mechanisms engaged through HST for depression patients.

Methods

We plan to enroll 50 subjects to be randomized into a 4-week HST intervention group and a waitlist group. A battery of psychological questionnaires will be administered at baseline and post-intervention timepoints, and electroencephalography (EEG) will be collected during compassion meditation guided by pre-recorded audio. The primary clinical outcome measures are on the feasibility of the intervention and research procedures, the primary mechanistic outcome measure is the post-intervention change in Heartbeat Evoked Potential (HEP) amplitude. Secondary outcome measures include changes in depression severity and EEG gamma spectral activity. Exploratory outcome measures include effects of HST on skin conductance response, heart rate variability, EEG spectral properties in other frequency bands, as well as a list of psychological questionnaires that measure depression and anxiety symptoms, emotion regulation, mindfulness, interoceptive awareness, self-compassion, gratitude, sleep quality, quality of life and social connectedness.

Results

Results not yet available.

Conclusion

This is the first study on the feasibility and interoceptive neurocardiac mechanism of HST. Our findings will provide frontier knowledge on the physiological working mechanism of behavioral interventions with an interoception-based meditative approach. https://clinicaltrials.gov/study/NCT05564533.

Large-scale effective connectivity analysis reveals the existence of two mutual inhibitory systems in patients with major depression

It is posited that cognitive and affective dysfunction in patients with major depression disorder (MDD) may be caused by dysfunctional signal propagation in the brain. By leveraging dynamic causal modeling, we investigated large-scale directed signal propagation (effective connectivity) among distributed large-scale brain networks with 43 MDD patients and 56 healthy controls. The results revealed the existence of two mutual inhibitory systems: the anterior default mode network, auditory network, sensorimotor network, salience network and visual networks formed an "emotional" brain, while the posterior default mode network, central executive networks, cerebellum and dorsal attention network formed a "rational brain". These two networks exhibited excitatory intra-system connectivity and inhibitory inter-system connectivity. Patients were characterized by potentiated intra-system connections within the "emotional/sensory brain", as well as over-inhibition of the "rational brain" by the "emotional/sensory brain". The hierarchical architecture of the large-scale effective connectivity networks was then analyzed using a PageRank algorithm which revealed a shift of the controlling role of the "rational brain" to the "emotional/sensory brain" in the patients. These findings inform basic organization of distributed large-scale brain networks and furnish a better characterization of the neural mechanisms of depression, which may facilitate effective treatment.

Late Luteal Subphase Food Craving Is Enhanced in Women with Obesity and Premenstrual Dysphoric Disorder (PMDD)

Dysregulated food craving is a complex weight-related behavior. To identify novel targets for enhancing the efficacy of weight loss interventions, we examined whether food craving varies across the menstrual cycle according to the abdominal obesity type and premenstrual dysphoric disorder (PMDD) diagnosis, and, if so, whether it is related to affective symptomatology. Reproductive-age women were classified into one of the four study groups according to whether they have abdominal obesity (AO) or are abdominally lean (AL), and the presence of PMDD: (1) AO:PMDD+ (n = 13), (2) AL:PMDD+ (n = 14), (3) AO:PMDD- (n = 15), and (4) AL:PMDD- (n = 16). Self-report measures as well as urinary luteinizing hormone (LH) tests were provided by the participants across 2-3 menstrual cycles. The ratings of food cravings were similar across the menstrual cycle, except the last, late luteal subphase as the AO:PMDD+ participants had the highest food craving rating. Irritability and depression were correlated with food cravings, but not in a distinctive manner across the menstrual cycle by group. Our study found that women with abdominal obesity and PMDD display a temporal vulnerability to a food-related behavior. The possibility of shared neurobiology between the two conditions is discussed and should be examined in future studies.

A review on linking stress, depression, and insulin resistance via low-grade chronic inflammation

Stress is a disturbance in homeostasis caused by psychological, physiological, or environmental factors. Prolonged reactions to chronic stress can be detrimental, resulting in various metabolic abnormalities, referred to as metabolic syndrome (MS). There is a reciprocal increased risk between MS and major depressive disorder. Recent studies established an association between inflammation and insulin signaling in type 2 diabetes mellitus with depression. In the present review, we discuss chronic low-grade inflammation, pathways of insulin resistance, and brain glucose metabolism in the context of neuroinflammation and depression. Specific attention is given to psychotropic drugs such as bupropion, mirtazapine, and nefazodone, anti-inflammatory drugs like Celecoxib (COX-2 inhibitor), Etanercept, adalimumab, IL-4Ra antagonist, Anti-IL- 17A antibody (Ixekizumab) and lifestyle modifications including exercise, dietary changes, and sleep hygiene. These therapeutic solutions offer potential in treating depression by targeting metabolic conditions like insulin resistance and inflammatory pathways. The article further explains the significance of a nutrition and antioxidants-rich diet, emphasizing the role of omega-3 fatty acids, vitamin D, zinc, and polyphenols, to improve immunity and activate anti-inflammatory signaling pathways.

Negative and positive interpretations of emotionally neutral situations modulate the desire to eat personally craved foods

Emotions play an important role in modulating food craving. Previous studies demonstrated that exposure to negative or positive stimuli can subsequently influence the desire to eat. However, in many daily situations, individuals self-generate their emotions, for example, by interpreting emotionally-neutral situations as positive or negative. So far, no studies have examined if and how positive and negative interpretations of emotionally-neutral situations modulate food craving. In this study, 65 healthy participants were asked to interpret emotionally-neutral images negatively or positively or observe the images naturally. Subsequently, participants rated their state negative/positive affect and their desire to eat their personally craved foods. The results demonstrate a lower desire to eat craved foods after negative interpretations and a higher desire to eat after positive interpretations, compared to an observe-naturally condition. Additionally, the impact of emotional interpretations on the desire to eat was mediated by participants' state negative/positive affect. These findings suggest that self-generated emotion as a result of negative/positive interpretations plays a significant role in modulating food craving. The results highlight the potential of modifying affective interpretations for the treatment of disorders that are characterized by both dysregulated food craving and emotion.

Threats to the emotional wellbeing of mainland Chinese students studying in Australia: an interpretivist study

PURPOSE

In 2017, international students contributed almost $32 billion to Australia's economy, more than half of which was attributable to students from China. Despite its historical popularity as a study destination, research suggests that these students confront numerous obstacles in pursuing their studies within Australia. In this study, the perspectives of these students were explored. The dominant issues raised by these students related to mental health and emotional wellbeing.

METHODS

Nineteen students in one Australian university participated in one-on-one in-depth semi-structured interviews. Data were analysed using grounded theory approaches. Three broad themes were generated in the study: psychological stress (which was linked to language barriers, shifts in pedagogy, and changes in lifestyle); perceived safety (which was linked to lack of security, safety and perceived racial discrimination); and social isolation (linked to reduced sense of belonging; lacking close personal connections; and feelings of loneliness and homesickness).

CONCLUSIONS

Results suggested that a tripartite model of interactive risk factors may be appropriate for exploring how international students fare emotionally with their new environments.

Uncovering the Neural Correlates of Anhedonia Subtypes in Major Depressive Disorder: Implications for Intervention Strategies

Major depressive disorder (MDD) represents a serious public health concern, negatively affecting individuals' quality of life and making a substantial contribution to the global burden of disease. Anhedonia is a core symptom of MDD and is associated with poor treatment outcomes. Variability in anhedonia components within MDD has been observed, suggesting heterogeneity in psychopathology across subgroups. However, little is known about anhedonia subgroups in MDD and their underlying neural correlates across subgroups. To address this question, we employed a hierarchical cluster analysis based on Temporal Experience of Pleasure Scale subscales in 60 first-episode, drug-naive MDD patients and 32 healthy controls. Then we conducted a connectome-wide association study and whole-brain voxel-wise functional analyses for identified subgroups. There were three main findings: (1) three subgroups with different anhedonia profiles were identified using a data mining approach; (2) several parts of the reward network (especially pallidum and dorsal striatum) were associated with anticipatory and consummatory pleasure; (3) different patterns of within- and between-network connectivity contributed to the disparities of anhedonia profiles across three MDD subgroups. Here, we show that anhedonia in MDD is not uniform and can be categorized into distinct subgroups, and our research contributes to the understanding of neural underpinnings, offering potential treatment directions. This work emphasizes the need for tailored approaches in the complex landscape of MDD. The identification of homogeneous, stable, and neurobiologically valid MDD subtypes could significantly enhance our comprehension and management of this multifaceted condition.

Divergent transcriptomic profiles in depressed individuals with hyper- and hypophagia implicating inflammatory status

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.

Dim Light at Night Promotes Circadian Disruption in Female Rats, at the Metabolic, Reproductive, and Behavioral Level

Inhabitants of urban areas are constantly exposed to light at night, which is an important environmental factor leading to circadian disruption. Streetlights filtering light through the windows and night dim light lamps are common sources of dim light at night (DLAN). The female population is susceptible to circadian disruption. The present study is aimed to determine the impact of DLAN on female Wistar rats circadian rhythms, metabolism, reproductive physiology, and behavior. After 5 weeks of DLAN exposure daily, oscillations in activity and body temperature of female rats are abolished. DLAN also decreases nocturnal food ingestion, which results in a diminishment in total food consumption. These alterations in the temporal organization of the body are associated with a significant decrease in melatonin plasmatic levels, reproductive disruptions, decreased exploration times, and marked anhedonia. This study highlights the importance of avoiding exposure to light at night, even at low intensities, to maintain the circadian organization of physiology, and denotes the great necessity of increasing the studies in females since the sexual dimorphism within the effects of desynchronizing protocols has been poorly studied.

Neuroanatomy of post-stroke depression: the association between symptom clusters and lesion location

Post-stroke depression affects about 30% of stroke patients and often hampers functional recovery. The diagnosis of depression encompasses heterogeneous symptoms at emotional, motivational, cognitive, behavioural or somatic levels. Evidence indicates that depression is caused by disruption of bio-aminergic fibre tracts between prefrontal and limbic or striatal brain regions comprising different functional networks. Voxel-based lesion-symptom mapping studies reported discrepant findings regarding the association between infarct locations and depression. Inconsistencies may be due to the usage of sum scores, thereby mixing different symptoms of depression. In this cross-sectional study, we used multivariate support vector regression for lesion-symptom mapping to identify regions significantly involved in distinct depressive symptom domains and global depression. MRI lesion data were included from 200 patients with acute first-ever ischaemic stroke (mean 0.9 ± 1.5 days of post-stroke). The Montgomery-Åsberg Depression Rating interview assessed depression severity in five symptom domains encompassing motivational, emotional and cognitive symptoms deficits, anxiety and somatic symptoms and was examined 8.4 days of post-stroke (±4.3). We found that global depression severity, irrespective of individual symptom domains, was primarily linked to right hemispheric lesions in the dorsolateral prefrontal cortex and inferior frontal gyrus. In contrast, when considering distinct symptom domains individually, the analyses yielded much more sensitive results in regions where the correlations with the global depression score yielded no effects. Accordingly, motivational deficits were associated with lesions in orbitofrontal cortex, dorsolateral prefrontal cortex, pre- and post-central gyri and basal ganglia, including putamen and pallidum. Lesions affecting the dorsal thalamus, anterior insula and somatosensory cortex were significantly associated with emotional symptoms such as sadness. Damage to the dorsolateral prefrontal cortex was associated with concentration deficits, cognitive symptoms of guilt and self-reproach. Furthermore, somatic symptoms, including loss of appetite and sleep disturbances, were linked to the insula, parietal operculum and amygdala lesions. Likewise, anxiety was associated with lesions impacting the central operculum, insula and inferior frontal gyrus. Interestingly, symptoms of anxiety were exclusively left hemispheric, whereas the lesion-symptom associations of the other domains were lateralized to the right hemisphere. In conclusion, this large-scale study shows that in acute stroke patients, differential post-stroke depression symptom domains are associated with specific structural correlates. Our findings extend existing concepts on the neural underpinnings of depressive symptoms, indicating that differential lesion patterns lead to distinct depressive symptoms in the first weeks of post-stroke. These findings may facilitate the development of personalized treatments to improve post-stroke rehabilitation.

Dissecting the mediating and moderating effects of depression on the associations between traits and coronary artery disease: A two-step Mendelian randomization and phenome-wide interaction study

Background

Depression is often present concurrently with coronary artery disease (CAD), a disease with which it shares many risk factors. However, the manner in which depression mediates and moderates the association between traits (including biomarkers, anthropometric indicators, lifestyle behaviors, etc.) and CAD is largely unknown.

Methods

In our causal mediation analyses using two-step Mendelian randomization (MR), univariable MR was first used to investigate the causal effects of 108 traits on liability to depression and CAD. The traits with significant causal effects on both depression and CAD, but not causally modulated by depression, were selected for the second-step analyses. Multivariable MR was used to estimate the direct effects (independent of liability to depression) of these traits on CAD, and the indirect effects (mediated via liability to depression) were calculated. To investigate the moderating effect of depression on the association between 364 traits and CAD, a cross-sectional phenome-wide interaction study (PheWIS) was conducted in a study population from UK Biobank (UKBB) (N=275,257). Additionally, if the relationship between traits and CAD was moderated by both phenotypic and genetically predicted depression at a suggestive level of significance (Pinteraction≤0.05) in the PheWIS, the results were further verified by a cohort study using Cox proportional hazards regression.

Results

Univariable MR indicated that 10 of 108 traits under investigation were significantly associated with both depression and CAD, which showed a similar direct effect compared to the total effect for most traits. However, the traits "drive faster than speed limit" and "past tobacco smoking" were both exceptions, with the proportions mediated by depression at 24.6% and 7.2%, respectively. In the moderation analyses, suggestive evidence of several traits was found for moderating effects of phenotypic depression or susceptibility to depression, as estimated by polygenic risk score, including chest pain when hurrying, reason of smoking quitting and weight change. Consistent results were observed in survival analyses and Cox regression.

Conclusion

The independent role of traits in CAD pathogenesis regardless of depression was highlighted in our mediation analyses, and the moderating effects of depression observed in our study may be helpful for CAD risk stratification and optimized allocation of scarce medical resources.

Psychological interventions for interoception in mental health disorders: A systematic review of randomized-controlled trials

Disturbed interoception (i.e., the sensing, awareness, and regulation of internal body signals) has been found across several mental disorders, leading to the development of interoception-based interventions (IBIs). Searching PubMed and PsycINFO, we conducted the first systematic review of randomized-controlled trials (RCTs) investigating the efficacy of behavioral IBIs at improving interoception and target symptoms of mental disorders in comparison to a non-interoception-based control condition [CRD42021297993]. Thirty-one RCTs fulfilled inclusion criteria. Across all studies, a pattern emerged with 20 (64.5%) RCTs demonstrating IBIs to be more efficacious at improving interoception compared to control conditions. The most promising results were found for post-traumatic stress disorder, irritable bowel syndrome, fibromyalgia and substance use disorders. Regarding symptom improvement, the evidence was inconclusive. The IBIs were heterogenous in their approach to improving interoception. The quality of RCTs was moderate to good. In conclusion, IBIs are potentially efficacious at improving interoception for some mental disorders. In terms of symptom reduction, the evidence is less promising. Future research on the efficacy of IBIs is needed.

Divergent transcriptomic profiles in depressed individuals with hyper- and hypophagia implicating inflammatory status

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.

Stress to inflammation and anhedonia: Mechanistic insights from preclinical and clinical models

Anhedonia, as evidenced by impaired pleasurable response to reward, reduced reward motivation, and/or deficits in reward-related learning, is a common feature of depression. Such deficits in reward processing are also an important clinical target as a risk factor for depression onset. Unfortunately, reward-related deficits remain difficult to treat. To address this gap and inform the development of effective prevention and treatment strategies, it is critical to understand the mechanisms that drive impairments in reward function. Stress-induced inflammation is a plausible mechanism of reward deficits. The purpose of this paper is to review evidence for two components of this psychobiological pathway: 1) the effects of stress on reward function; and 2) the effects of inflammation on reward function. Within these two areas, we draw upon preclinical and clinical models, distinguish between acute and chronic effects of stress and inflammation, and address specific domains of reward dysregulation. By addressing these contextual factors, the review reveals a nuanced literature which might be targeted for additional scientific inquiry to inform the development of precise interventions.

A meta-analysis investigating the outcomes and correlation between heart rate variability biofeedback training on depressive symptoms and heart rate variability outcomes versus standard treatment in comorbid adult populations

BACKGROUND AND AIM

Heart rate variability biofeedback (HRVB) has previously been used to ameliorate depressive symptoms but its uses for tackling depressive symptoms in an array of comorbid adult patients is less established. This meta-analysis aims to evaluate whether HRVB is a useful tool to reduce depressive symptoms and improve HRV relative to standard treatment in adult comorbid populations, while also attempting to establish the association between the two outcomes.

METHODS

An extensive literature review was conducted using several databases including PubMed, Cinahl, Medline, Web of science and clinical.gov/UK register. A total of 149 studies were identified with 9 studies, totalling 428 participants were analysed using a random effects model.

RESULTS

Depressive outcomes yielded a mean effect size g=0.478 (CI 95% 0.212, 0.743) with HRV outcomes, yielding a mean effect size of g=0.223 (95% CI 0.036 to 0.411). Total heterogeneity was non-significant for depressive outcomes (Q= 13.77, p=0.088 I^=42.86%) and HRV (Q= 1.598, p=0.991, I^=0.000%) which indicates that little variance existed for the included studies.

CONCLUSIONS

In summary, the outcomes demonstrate that HRVB can improve both clinically relevant depressive symptoms and physiological HRV outcomes in various comorbid conditions in adult populations, while the correlation between the two was moderately negative, but non-significant.

Alterations in resting-state functional activity and connectivity for major depressive disorder appetite and weight disturbance phenotypes

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.

Nutrient Inadequacy in Korean Young Adults with Depression: A Case Control Study

The role of diet is gaining attention among the modifiable factors associated with depression; thus, this case-control study examined the association between nutrition and depression in young Korean adults. Dietary surveys in individuals with depression (n = 39) and age- and gender-matched controls (n = 76) were conducted using food records and food frequency questionnaires. Men with depression consumed less mushrooms and meat, while women consumed significantly less grains (p < 0.05). Overall, the depression group consumed less energy and nutrients, and the difference was more pronounced in men. The male depression group had lower nutrient adequacy ratio (NAR) for energy, protein, vitamin A, thiamine, niacin, folate, and phosphorus, whereas the female depression group had lower NARs for energy, protein, niacin, and vitamin B₁₂. The depression group had a significantly lower mean adequacy ratio in both genders. Furthermore, the proportion of inappropriate nutrient intake was higher in both genders of the depression group, exhibiting significant differences in energy, protein, niacin, folate, and zinc in men and energy, riboflavin, folate, and vitamin C in women. Hence, both men and women in the depression group had poor nutrient intake and high rates of nutrient inadequacy and improper consumption. This suggests that the quantity and quality of meals should be improved for individuals with depressive symptoms.

How gut hormones shape reward: A systematic review of the role of ghrelin and GLP-1 in human fMRI

The gastrointestinal hormones ghrelin and glucagon-like peptide-1 (GLP-1) have opposite secretion patterns, as well as opposite effects on metabolism and food intake. Beyond their role in energy homeostasis, gastrointestinal hormones have also been suggested to modulate the reward system. However, the potential of ghrelin and GLP-1 to modulate reward responses in humans has not been systematically reviewed before. To evaluate the convergence of published results, we first conduct a multi-level kernel density meta-analysis of studies reporting a positive association of ghrelin (N_comb = 353, 18 contrasts) and a negative association of GLP-1 (N_comb = 258, 12 contrasts) and reward responses measured using task functional magnetic resonance imaging (fMRI). Second, we complement the meta-analysis using a systematic literature review, focusing on distinct reward phases and applications in clinical populations that may account for variability across studies. In line with preclinical research, we find that ghrelin increases reward responses across studies in key nodes of the motivational circuit, such as the nucleus accumbens, pallidum, putamen, substantia nigra, ventral tegmental area, and the dorsal mid insula. In contrast, for GLP-1, we did not find sufficient convergence in support of reduced reward responses. Instead, our systematic review identifies potential differences of GLP-1 on anticipatory versus consummatory reward responses. Based on a systematic synthesis of available findings, we conclude that there is considerable support for the neuromodulatory potential of gut-based circulating peptides on reward responses. To unlock their potential for clinical applications, it may be useful for future studies to move beyond anticipated rewards to cover other reward facets.

Folate deprivation induced neuroinflammation impairs cognition

Nutritional status is associated with many neurocognitive diseases. Folate is one of the micronutrients, and its deficiency is associated with clinical outcomes of neurological diseases. Nevertheless, molecular mechanism behind the folate deficiency induced neurological disorders are not well-known. We have hypothesized that folate-deficiency is a cardinal determinant responsible for manifestation of cognitive impairment through inflammation mediated neurodegenerative pathologies. Objective of the current study was to assess whether folate deficiency is associated with cognitive dysfunction or is merely an epiphenomenon and to identify the underlying mechanisms. We developed folate insufficient zebrafish model through intra-peritoneal treatment of methotrexate. T-maze test was carried to assess the spatial learning and memory of the fish. Higher latency of the folate-deprived zebrafishes in the T-maze test is a reflection of altered cognition. This result is supported by declined levels of dopamine and serotonin, neurotransmitters linked with learning and memory. Elevated IL-6 and CRP in peripheral blood, along with increased expression of NF-ĸB in brain indicates manifestation of neuroinflammation. Indeed, together with upregulation of maptb gene it can be implied that folate deficiency acts as a risk factor for neurodegeneration in the form of tauopathies. Furthermore, diminished localisation of synaptopodin, a protein linked to neural plasticity, suggests that neuroinflammation caused by folate deprivation hampers the plasticity of brain. Histological analysis of brain revealed the development of histopathological features including spongiform degeneration and neuronal loss in folate deprived condition. We thus conclude that folate deficiency results in NF-ĸB activation, which through multiple processes mediated by neuroinflammation could lead to cognitive decline.

Collateralizing ventral subiculum melanocortin 4 receptor circuits regulate energy balance and food motivation

Hippocampal dysfunction is associated with major depressive disorder, a serious mental illness characterized by not only depressed mood but also appetite disturbance and dysregulated body weight. However, the underlying mechanisms by which hippocampal circuits regulate metabolic homeostasis remain incompletely understood. Here we show that collateralizing melanocortin 4 receptor (MC4R) circuits in the ventral subiculum (vSUB), one of the major output structures of the hippocampal formation, affect food motivation and energy balance. Viral-mediated cell type- and projection-specific input-output circuit mapping revealed that the nucleus accumbens shell (NAcSh)-projecting vSUB^MC4R+ neurons send extensive collateral projections of to various hypothalamic nuclei known to be important for energy balance, including the arcuate, ventromedial and dorsomedial nuclei, and receive monosynaptic inputs mainly from the ventral CA1 and the anterior paraventricular nucleus of thalamus. Chemogenetic activation of NAcSh-projecting vSUB^MC4R+neurons lead to increase in motivation to obtain palatable food without noticeable effect on homeostatic feeding. Viral-mediated restoration of MC4R signaling in the vSUB partially restores obesity in MC4R-null mice without affecting anxiety- and depression-like behaviors. Collectively, these results delineate vSUB^MC4R+ circuits to the unprecedented level of precision and identify the vSUB^MC4R signaling as a novel regulator of food reward and energy balance.

A common neural code for representing imagined and inferred tastes

Inferences about the taste of foods are a key aspect of our everyday experience of food choice. Despite this, gustatory mental imagery is a relatively under-studied aspect of our mental lives. In the present study, we examined subjects during high-field fMRI as they actively imagined basic tastes and subsequently viewed pictures of foods dominant in those specific taste qualities. Imagined tastes elicited activity in the bilateral dorsal mid-insula, one of the primary cortical regions responsive to the experience of taste. In addition, within this region we reliably decoded imagined tastes according to their dominant quality - sweet, sour, or salty - thus indicating that, like actual taste, imagined taste activates distinct quality-specific neural patterns. Using a cross-task decoding analysis, we found that the neural patterns for imagined tastes and food pictures in the mid-insula were reliably similar and quality-specific, suggesting a common code for representing taste quality regardless of whether explicitly imagined or automatically inferred when viewing food. These findings have important implications for our understanding of the mechanisms of mental imagery and the multimodal nature of presumably primary sensory brain regions like the dorsal mid-insula.