A Functional Interleukin-18 Haplotype Predicts Depression and Anxiety through Increased Threat-Related Amygdala Reactivity in Women but Not Men.

Common functional polymorphisms in the gene encoding interleukin-18 (IL18), a cytokine belonging to the IL-1 superfamily that can induce synthesis of several other cytokines, have been associated with major depressive episodes following the experience of stressful life events. The neural mechanisms underlying these associations remain unexamined. Here we use an imaging genetics strategy to examine the effects of risk-related IL18 haplotypes comprising rs187238 and rs1946518 on threat-related amygdala reactivity and, through an indirect effect, stress-related symptoms of depression and anxiety in 448 non-Hispanic Caucasian university students. Analyses indicated that women but not men possessing an IL18 haplotype comprising both risk-related alleles evidenced increased threat-related left centromedial amygdala reactivity relative to other haplotype groups. Moreover, in women only, increased threat-related left centromedial amygdala reactivity predicted increased symptoms of depression and anxiety in individuals also reporting higher levels of life stress. Path analyses revealed a significant indirect effect of IL18 risk haplotype on symptoms of depression and anxiety through increased threat-related amygdala reactivity. These results suggest that a common functional IL18 haplotype associated with heightened proinflammatory responses confers susceptibility to stress-related depression and anxiety through effects on threat-related amygdala function, a risk pathway specific to women. If replicated, these patterns can inform the search for personalized interventions targeting neurobiological pathways of risk associated with inflammation.

Hypothalamic-pituitary-adrenal axis genetic variation and early stress moderates amygdala function.

Early life stress may precipitate psychopathology, at least in part, by influencing amygdala function. Converging evidence across species suggests that links between childhood stress and amygdala function may be dependent upon hypothalamic-pituitary-adrenal (HPA) axis function. Using data from college-attending non-Hispanic European-Americans (n=308) who completed the Duke Neurogenetics Study, we examined whether early life stress (ELS) and HPA axis genetic variation interact to predict threat-related amygdala function as well as psychopathology symptoms. A biologically-informed multilocus profile score (BIMPS) captured HPA axis genetic variation (FKBP5 rs1360780, CRHR1 rs110402; NR3C2 rs5522/rs4635799) previously associated with its function (higher BIMPS are reflective of higher HPA axis activity). BOLD fMRI data were acquired while participants completed an emotional face matching task. ELS and depression and anxiety symptoms were measured using the childhood trauma questionnaire and the mood and anxiety symptom questionnaire, respectively. The interaction between HPA axis BIMPS and ELS was associated with right amygdala reactivity to threat-related stimuli, after accounting for multiple testing (empirical-p=0.016). Among individuals with higher BIMPS (i.e., the upper 21.4%), ELS was positively coupled with threat-related amygdala reactivity, which was absent among those with average or low BIMPS. Further, higher BIMPS were associated with greater self-reported anxious arousal, though there was no evidence that amygdala function mediated this relationship. Polygenic variation linked to HPA axis function may moderate the effects of early life stress on threat-related amygdala function and confer risk for anxiety symptomatology. However, what, if any, neural mechanisms may mediate the relationship between HPA axis BIMPS and anxiety symptomatology remains unclear.

Intolerance of uncertainty, social anxiety, and generalized anxiety: Differences by diagnosis and symptoms.

Research suggests that Intolerance of Uncertainty (IU) is related to the severity of suffering in Generalized Anxiety Disorder (GAD). However, its role in Social Anxiety Disorder (SAD) has not been extensively studied. This study examines IU in a clinical sample of 248 individuals referred to a tertiary care clinic. Few individuals had a diagnosis of pure SAD or pure GAD, but we examined differences of IU scores by diagnostic category. We further examined the relationships between IU scores, social anxiety scores, and worry through a structural equation model. We found that diagnostic category (SAD versus GAD) accounted for little variability in IU scores, but IU scores were strongly related to symptoms of both GAD and SAD. Results highlight that IU is related to both social anxiety and worry; however aspects of IU associated with being unable to act or avoiding uncertainty are more strongly associated with SAD symptoms, whereas aspects of IU more associated with general stress and perceiving uncertainty as unfair are more strongly associated with GAD symptoms. Our results suggest that IU is an important concept for both social anxiety and generalized anxiety, however the relationship between IU and symptoms of these disorders manifests differently.

Disgust proneness and associated neural substrates in obesity.

Defects in experiencing disgust may contribute to obesity by allowing for the overconsumption of food. However, the relationship of disgust proneness and its associated neural locus has yet to be explored in the context of obesity. Thirty-three participants (17 obese, 16 lean) completed the Disgust Propensity and Sensitivity Scale-Revised and a functional magnetic resonance imaging paradigm where images from 4 categories (food, contaminates, contaminated food or fixation) were randomly presented. Independent two-sample t-tests revealed significantly lower levels of Disgust Sensitivity for the obese group (mean score = 14.7) compared with the lean group (mean score = 17.6, P = 0.026). The obese group had less activation in the right insula than the lean group when viewing contaminated food images. Multiple regression with interaction analysis revealed one left insula region where the association of Disgust Sensitivity scores with activation differed by group when viewing contaminated food images. These interaction effects were driven by the negative correlation of Disgust Sensitivity scores with beta values extracted from the left insula in the obese group (r = -0.59) compared with a positive correlation in the lean group (r = 0.65). Given these body mass index-dependent differences in Disgust Sensitivity and neural responsiveness to disgusting food images, it is likely that altered Disgust Sensitivity may contribute to obesity.

Human ecstasy (MDMA) polydrug users have altered brain activation during semantic processing.

RATIONALE: Ecstasy (3,4-methylenedioxymethamphetamine [MDMA]) polydrug users have verbal memory performance that is statistically significantly lower than that of control subjects. Studies have correlated long-term MDMA use with altered brain activation in regions that play a role in verbal memory. OBJECTIVES: The aim of our study was to examine the association of lifetime ecstasy use with semantic memory performance and brain activation in ecstasy polydrug users. METHODS: A total of 23 abstinent ecstasy polydrug users (age = 24.57 years) and 11 controls (age = 22.36 years) performed a two-part functional magnetic resonance imaging (fMRI) semantic encoding and recognition task. To isolate brain regions activated during each semantic task, we created statistical activation maps in which brain activation was greater for word stimuli than for non-word stimuli (corrected p < 0.05). RESULTS: During the encoding phase, ecstasy polydrug users had greater activation during semantic encoding bilaterally in language processing regions, including Brodmann areas 7, 39, and 40. Of this bilateral activation, signal intensity with a peak T in the right superior parietal lobe was correlated with lifetime ecstasy use (r s = 0.43, p = 0.042). Behavioral performance did not differ between groups. CONCLUSIONS: These findings demonstrate that ecstasy polydrug users have increased brain activation during semantic processing. This increase in brain activation in the absence of behavioral deficits suggests that ecstasy polydrug users have reduced cortical efficiency during semantic encoding, possibly secondary to MDMA-induced 5-HT neurotoxicity. Although pre-existing differences cannot be ruled out, this suggests the possibility of a compensatory mechanism allowing ecstasy polydrug users to perform equivalently to controls, providing additional support for an association of altered cerebral neurophysiology with MDMA exposure.

Efficacy of acupuncture treatment of sexual dysfunction secondary to antidepressants.

BACKGROUND: Antidepressants including selective serotonin reuptake inhibitors (SSRIs) and serotonin noradrenaline reuptake inhibitors (SNRIs) are known to cause secondary sexual dysfunction with prevalence rates as high as 50%-90%. Emerging research is establishing that acupuncture may be an effective treatment modality for sexual dysfunction including impotence, loss of libido, and an inability to orgasm. OBJECTIVES: The purpose of this study was to examine the potential benefits of acupuncture in the management of sexual dysfunction secondary to SSRIs and SNRIs. SUBJECTS: Practitioners at the START Clinic referred participants experiencing adverse sexual events from their antidepressant medication for acupuncture treatment at the Mood and Anxiety Disorders, a tertiary care mood and anxiety disorder clinic in Toronto. DESIGN: Participants received a Traditional Chinese Medicine assessment and followed an acupuncture protocol for 12 consecutive weeks. The acupuncture points used were Kidney 3, Governing Vessel 4, Urinary Bladder 23, with Heart 7 and Pericardium 6. Participants also completed a questionnaire package on a weekly basis. OUTCOMES MEASURED: The questionnaire package consisted of self-report measures assessing symptoms of depression, anxiety, and various aspects of sexual function. RESULTS: Significant improvement among male participants was noted in all areas of sexual functioning, as well as in both anxiety and depressive symptoms. Female participants reported a significant improvement in libido and lubrication and a nonsignificant trend toward improvement in several other areas of function. CONCLUSIONS: This study suggests a potential role for acupuncture in the treatment of the sexual side-effects of SSRIs and SNRIs as well for a potential benefit of integrating medical and complementary and alternative practitioners.

A multicomponent yoga-based, breath intervention program as an adjunctive treatment in patients suffering from generalized anxiety disorder with or without comorbidities.

OBJECTIVES: The aim of this study is to evaluate the efficacy and tolerability of Sudarshan Kriya Yoga (SKY) course in generalized anxiety disorder (GAD) outpatients, who after eight weeks of an appropriate dose of traditional therapy had not yet achieved remission. SUBJECTS: The adult participants (18-65 years) were outpatients with a primary diagnosis of GAD with or without comorbidities on the Mini-International Neuropsychiatric Interview (MINI). Participants had a minimum of eight weeks standard treatment with an appropriate dose of a standard prescription anxiolytic, a clinician global impression-severity (CGI-S) score of 5-7, a Hamilton anxiety scale (HAM-A) total score ≥20 including a score of >2 on the anxious mood and tension items. MATERIALS AND METHODS: Forty-one patients were enrolled in an open-label trial of the SKY course as an adjunct to standard treatment of GAD at the START Clinic for Mood and Anxiety Disorders, a tertiary care mood and anxiety disorder clinic in Toronto. The SKY course was administered over five days (22 h total). Subjects were encouraged to practice the yoga breathing techniques at home for 20 min per day after the course and were offered group practice sessions for 2 h once a week led by certified yoga instructors. The primary outcome measure was the mean change from pre-treatment on the HAM-A scale. Psychological measures were obtained at baseline and four weeks after completing the intervention. RESULTS: Thirty-one patients completed the program (mean age 42.6 ± 13.3 years). Among completers, significant reductions occurred in the pre- and post-intervention mean HAM-A total score (t=4.59; P<0.01) and psychic subscale (t=5.00; P≤0.01). The response rate was 73% and the remission rate 41% as measured on the HAM-A. CONCLUSION: The results of this small pilot trial suggest that the SKY course represents a potentially valuable adjunct to standard pharmacotherapy in patients with GAD or treatment-resistant GAD, and warrants further investigation. In particular, changes in worry and body symptoms showed significant improvements that may further our understanding of the mechanism of change in the tolerance of anxiety and worry.

Evidence for chronically altered serotonin function in the cerebral cortex of female 3,4-methylenedioxymethamphetamine polydrug users.

CONTEXT: MDMA (3,4-methylenedioxymethamphetamine, also popularly known as "ecstasy") is a popular recreational drug that produces loss of serotonin axons in animal models. Whether MDMA produces chronic reductions in serotonin signaling in humans remains controversial. OBJECTIVE: To determine whether MDMA use is associated with chronic reductions in serotonin signaling in the cerebral cortex of women as reflected by increased serotonin(2A) receptor levels. DESIGN: Cross-sectional case-control study comparing serotonin(2A) receptor levels in abstinent female MDMA polydrug users with those in women who did not use MDMA (within-group design assessing the association of lifetime MDMA use and serotonin(2A) receptors). Case participants were abstinent from MDMA use for at least 90 days as verified by analysis of hair samples. The serotonin(2A) receptor levels in the cerebral cortex were determined using serotonin(2A)-specific positron emission tomography with radioligand fluorine 18-labeled setoperone as the tracer. SETTING: Academic medical center research laboratory. PARTICIPANTS: A total of 14 female MDMA users and 10 women who did not use MDMA (controls). The main exclusion criteria were nondrug-related DSM-IV Axis I psychiatric disorders and general medical illness. MAIN OUTCOME MEASURES: Cortical serotonin(2A) receptor nondisplaceable binding potential (serotonin(2A)BP(ND)). RESULTS: MDMA users had increased serotonin(2A)BP(ND) in occipital-parietal (19.7%), temporal (20.5%), occipitotemporal-parietal (18.3%), frontal (16.6%), and frontoparietal (18.5%) regions (corrected P < .05). Lifetime MDMA use was positively associated with serotonin(2A)BP(ND) in frontoparietal (ß = 0.665; P = .007), occipitotemporal (ß = 0.798; P = .002), frontolimbic (ß = 0.634; P = .02), and frontal (ß = 0.691; P = .008) regions. In contrast, there were no regions in which MDMA use was inversely associated with receptor levels. There were no statistically significant effects of the duration of MDMA abstinence on serotonin(2A)BP(ND). CONCLUSIONS: The recreational use of MDMA is associated with long-lasting increases in serotonin(2A) receptor density. Serotonin(2A) receptor levels correlate positively with lifetime MDMA use and do not decrease with abstinence. These results suggest that MDMA use produces chronic serotonin neurotoxicity in humans. Given the broad role of serotonin in human brain function, the possibility for therapeutic MDMA use, and the widespread recreational popularity of this drug, these results have critical public health implications.

Human Ecstasy use is associated with increased cortical excitability: an fMRI study.

The serotonergic neurotoxin, 3,4-methylenedioxymethamphetamine (MDMA/Ecstasy), is a highly popular recreational drug. Human recreational MDMA users have neurocognitive and neuropsychiatric impairments, and human neuroimaging data are consistent with animal reports of serotonin neurotoxicity. However, functional neuroimaging studies have not found consistent effects of MDMA on brain neurophysiology in human users. Several lines of evidence suggest that studying MDMA effects in visual system might reveal the general cortical and subcortical neurophysiological consequences of MDMA use. We used 3 T functional magnetic resonance imaging during visual stimulation to compare visual system lateral geniculate nucleus (LGN) and Brodmann Area (BA) 17 and BA 18 activation in 20 long abstinent (479.95±580.65 days) MDMA users and 20 non-MDMA user controls. Lifetime quantity of MDMA use was strongly positively correlated with blood oxygenation level-dependent (BOLD) signal intensity in bilateral LGN (r(s)=0.59; p=0.007), BA 17 (r(s)=0.50; p=0.027), and BA 18 (r(s)=0.48; p=0.031), and with the spatial extent of activation in BA 17 (r(s)=0.059; p=0.007) and BA 18 (r(s)=0.55; p=0.013). There were no between-group differences in brain activation in any region, but the heaviest MDMA users showed a significantly greater spatial extent of activation than controls in BA 17 (p=0.031) and BA 18 (p=0.049). These results suggest that human recreational MDMA use may be associated with a long-lasting increase in cortical excitability, possibly through loss of serotonin input to cortical and subcortical regions. When considered in the context of previous results, cortical hyper-excitability may be a biomarker for MDMA-induced serotonin neurotoxicity.

A randomized, double-blind, placebo-controlled pilot study of a probiotic in emotional symptoms of chronic fatigue syndrome.

Chronic fatigue syndrome (CFS) is complex illness of unknown etiology. Among the broad range of symptoms, many patients report disturbances in the emotional realm, the most frequent of which is anxiety. Research shows that patients with CFS and other so-called functional somatic disorders have alterations in the intestinal microbial flora. Emerging studies have suggested that pathogenic and non-pathogenic gut bacteria might influence mood-related symptoms and even behavior in animals and humans. In this pilot study, 39 CFS patients were randomized to receive either 24 billion colony forming units of Lactobacillus casei strain Shirota (LcS) or a placebo daily for two months. Patients provided stool samples and completed the Beck Depression and Beck Anxiety Inventories before and after the intervention. We found a significant rise in both Lactobacillus and Bifidobacteria in those taking the LcS, and there was also a significant decrease in anxiety symptoms among those taking the probiotic vs controls (p = 0.01). These results lend further support to the presence of a gut-brain interface, one that may be mediated by microbes that reside or pass through the intestinal tract.