Sex hormone activity in alcohol addiction: integrating organizational and activational effects

Sex and sobriety: Human brain structure and function in AUD abstinence

Women are drinking alcohol as much as men for the first time in history. Women experience more health-related consequences from alcohol use disorder (AUD), like increased prevalence of alcohol-related cancers, faster progression of alcohol-related liver disease, and greater risk for relapse compared to men. Thus, sex differences in chronic alcohol use pose a substantial public health problem. Despite these evident sex differences, our understanding of how these differences present during alcohol abstinence is limited. Investigations of brain structure and function are therefore critical for disentangling factors that lead to sex differences in AUD abstinence. This review will discuss current human neuroimaging data on sex differences in alcohol abstinence, focusing on structural and functional brain measures. Current structural imaging literature reveals that abstinent men have smaller gray and white matter volume and weaker structural connectivity compared to control men. Interestingly, abstinent women do not show differences in brain structure when compared to controls; instead, abstinent women show a relation between alcohol use and decreased measures of brain structure. Current functional brain studies reveal that abstinent men exhibit greater brain activation and stronger task-based functional connectivity to aversive stimuli than control men, while abstinent women exhibit lesser brain activation and weaker task-based functional connectivity than control women. Together, the current literature suggests that sex differences persist well into alcohol abstinence and impact brain structure and function differently. Understanding how men and women differ during alcohol abstinence can improve our understanding of sex-specific effects of alcohol, which will be critical to augment treatment methods to better serve women.

Neuronal biomarkers as potential therapeutic targets for drug addiction related to sex differences in the brain: Opportunities for personalized treatment approaches

Biological sex disparities manifest at various stages of drug addiction, including craving, substance abuse, abstinence, and relapse. These discrepancies are underpinned by notable distinctions in neurobiological substrates, encompassing brain structures, functions, and neurotransmitter systems implicated in drug addiction. Neuronal biomarkers, such as neurotransmitters, signaling proteins, and genes may be associated with the diagnosis, prognosis, and treatment outcomes in both biological sexes afflicted by drug abuse. Sex differences in the neural reward system, mainly through dopaminergic transmission during drug abuse, can be attributed to modifications in neurotransmitter systems and signaling pathways. This results in distinct patterns of neural activation and responsiveness to addictive substances in males and females. Sex hormones, the estrus/menstrual cycle, and cerebral neurochemistry contribute to the progression of psychological and physiological dependence in both male and female individuals grappling with addiction. Moreover, the alteration of sex hormone balance and neurotransmitter release plays a pivotal role in substance use disorders, subsequently modulating cognitive functions pertinent to reward, including memory formation, decision-making, and locomotor activity. Comparative investigations reveal distinctions in brain region volume, gene expression, neuronal firing, and circuitry in substance use disorders affecting individuals of both biological sexes. This review examines prevalent substance use disorders to elucidate the impact of sex hormones as therapeutic biomarkers on the mesocorticolimbic neurotransmitter systems via diverse mechanisms within the addicted brain. We underscore the imperative necessity of considering these variations to gain a deeper comprehension of addiction mechanisms and potentially discern sex-specific neuronal biomarkers for tailored therapeutic interventions.

Associations of Menstrual Cycle and Progesterone-to-Estradiol Ratio With Alcohol Consumption in Alcohol Use Disorder: A Sex-Separated Multicenter Longitudinal Study

OBJECTIVE

Alcohol use disorder (AUD) constitutes a critical public health issue and has sex-specific characteristics. Initial evidence suggests that progesterone and estradiol might reduce or increase alcohol intake, respectively. However, there is a need for a better understanding of how the menstrual cycle in females and the ratio of progesterone to estradiol in females and males influence alcohol use patterns in individuals with AUD.

METHODS

In this sex-separated multicenter longitudinal study, the authors analyzed 12-month data on real-life alcohol use (from 21,460 smartphone entries), menstrual cycle, and serum progesterone-to-estradiol ratios (from 667 blood samples at four individual study visits) in 74 naturally cycling females and 278 males with AUD between 2020 and 2022, using generalized and general linear mixed modeling.

RESULTS

Menstrual cycle phases were significantly associated with binge drinking and progesterone-to-estradiol ratio. During the late luteal phase, females showed a lower predicted binge drinking probability of 13% and a higher predicted marginal mean of progesterone-to-estradiol ratio of 95 compared with during the menstrual, follicular, and ovulatory phases (binge drinking probability and odds ratios vs. late luteal phase, respectively: 17%, odds ratio=1.340, 95% CI=1.031, 1.742; 19%, odds ratio=1.523, 95% CI=1.190, 1.949; and 20%, odds ratio=1.683, 95% CI=1.285, 2.206; difference in progesterone-to-estradiol ratios, respectively: -61, 95% CI=-105.492, -16.095; -78, 95% CI=-119.322, -37.039; and -71, 95% CI=-114.568, -27.534). In males, a higher progesterone-to-estradiol ratio was related to lower probabilities of binge drinking and of any alcohol use, with a 10-unit increase in the hormone ratio resulting in odds ratios of 0.918 (95% CI=0.843, 0.999) and 0.914 (95% CI=0.845, 0.988), respectively.

CONCLUSIONS

These ecologically valid findings suggest that high progesterone-to-estradiol ratios can have a protective effect against problematic alcohol use in females and males with AUD, highlighting the progesterone-to-estradiol ratio as a promising treatment target. Moreover, the results indicate that females with AUD may benefit from menstrual cycle phase-tailored treatments.

Substance Use Over Time Among Sexual and Gender Minority People: Differences at the Intersection of Sex and Gender

Purpose: Sexual and gender minority (SGM) people are at greater risk for substance use than heterosexual and cisgender people, but most prior work is limited by cross-sectional analyses or the examination of single substance use. This study examined substance use over time among SGM people to identify patterns of polysubstance use at the intersection of sex and gender. Methods: Data were collected annually over 4 years from SGM respondents (n = 11,822) in The Population Research in Identity and Disparities for Equality (PRIDE) Study. Differences in substance use patterns (any prior 30-day use of 15 substances) by gender subgroup were examined with latent class analysis, and multinomial regression models tested relationships between gender subgroup and substance use. Results: Eight classes of substance use were observed. The three most common patterns were low substance use (49%), heavy episodic alcohol use (≥5 alcoholic drinks on one occasion) with some cannabis and tobacco use (14%), and cannabis use with some tobacco and declining heavy episodic alcohol use (13%). Differences observed included lower odds of patterns defined by heavy episodic alcohol use with some cannabis and tobacco use in all gender subgroups relative to cisgender men and persons with low substance use (odds ratios [ORs] 0.26-0.60). Gender expansive people assigned female at birth, gender expansive people assigned male at birth, and transgender men had greater odds of reporting cannabis use with small percentages of heavy episodic alcohol and tobacco use (ORs: 1.41-1.60). Conclusion: This study suggests that there are unique patterns of polysubstance use over time among gender subgroups of SGM people.

Cocaine and amphetamine regulated transcript (CART) mediates sex differences in binge drinking through central taste circuits

The neuropeptide cocaine- and amphetamine-regulated transcript (CART) has been implicated in alcohol consumption and reward behaviours, yet mechanisms mediating these effects have yet to be identified. Using a transgenic CART knockout (KO) mouse line we uncovered a sexually dimorphic effect of CART in binge drinking, with male CART KO mice increasing intake, whilst female CART KO mice decreased their alcohol intake compared to controls. Female CART KO mice show greater sensitivity to bitter solutions that can be overshadowed through addition of a sweetener, implicating taste as a factor. Further we identify that this is not driven through peripherally circulating sex hormones, but the central nucleus of the amygdala (CeA) is a locus where CART contributes to the regulation of alcohol consumption, with CeA CART neutralisation specifically reducing plain alcohol, but not sweetened alcohol consumption in female mice. These findings may have implications for the development of sex-specific treatment options for alcohol use disorders through targeting the CART system.

Stress and gonadal steroid influences on alcohol drinking and withdrawal, with focus on animal models in females

Sexually dimorphic effects of alcohol, following binge drinking, chronic intoxication, and withdrawal, are documented at the level of the transcriptome and in behavioral and physiological responses. The purpose of the current review is to update and to expand upon contributions of the endocrine system to alcohol drinking and withdrawal in females, with a focus on animal models. Steroids important in the hypothalamic-pituitary-gonadal and hypothalamic-pituitary-adrenal axes, the reciprocal interactions between these axes, the effects of chronic alcohol use on steroid levels, and the genomic and rapid membrane-associated effects of steroids and neurosteroids in models of alcohol drinking and withdrawal are described. Importantly, comparison between males and females highlight some divergent effects of sex- and stress-steroids on alcohol drinking- and withdrawal-related behaviors, and the distinct differences in response emphasize the importance of considering sex in the development of novel pharmacotherapies for the treatment of alcohol use disorder.

Sex-specific association between prenatal androgenization (second-to-fourth digit length ratio) and frontal brain volumes in adolescents

Prenatal androgenization associates sex-dependently with behavior and mental health in adolescence and adulthood, including risk-taking, emotionality, substance use, and depression. However, still little is known on how it affects underlying neural correlates, like frontal brain control regions. Thus, we tested whether prenatal androgen load is sex-dependently related to frontal cortex volumes in a sex-balanced adolescent sample. In a cross-sectional magnetic resonance imaging study, we examined 61 adolescents (28 males, 33 females; aged 14 or 16 years) and analyzed associations of frontal brain region volumes with the second-to-fourth digit length ratio (2D:4D), an established marker for prenatal androgenization, using voxel-based morphometry in a region-of-interest approach. Lower 2D:4D (indicative of higher prenatal androgen load) correlated significantly with smaller volumes of the right anterior cingulate cortex (r-ACC; β = 0.45) in male adolescents and with larger volumes of the left inferior frontal gyrus orbital part (l-IFGorb; β = - 0.38) in female adolescents. The regression slopes of 2D:4D on the r-ACC also differed significantly between males and females. The study provides novel evidence that prenatal androgenization may influence the development of the frontal brain in a sex- and frontal brain region-specific manner. These effects might contribute to the well-known sex differences in risk-taking, emotionality, substance use, and depression. Future research is needed to elucidate the role of prenatal androgenization within the biopsychosocial model.

The Effect of Digital Mindfulness Interventions on Depressive, Anxiety, and Stress Symptoms in Pregnant Women: A Systematic Review and Meta-Analysis

Introduction. Pregnancy is a unique time in a woman's life that can be both exciting and challenging. It is also a period that can be associated with significant stress, anxiety, and depression, which can have negative consequences for both the mother and the baby. Mindfulness interventions are known to be a well-suited treatment and prevention method for psychiatric symptoms in pregnancy, and web-based applications have been explored. We here present an up-to-date systematic review and meta-analysis of randomized-controlled trials to investigate the effect of digital-based mindfulness interventions on depressive, anxiety, and stress symptoms during pregnancy. Methods. The systematic literature search and data extraction was performed by two independent raters. It resulted in 13 eligible studies overall comprising 1373 participants. We conducted random-effects meta-analyses for depressive, anxiety, and stress symptoms after completion of a digital mindfulness intervention (compared to a control group). Results. Digital mindfulness intervention methods were significantly able to reduce depression (g = -0.47, 95% CI [-0.9; -0.09]) and anxiety symptoms (g = -0.41, 95% CI [-0.77; -0.05]), but not stress symptoms. These effects were moderated by the attrition rate (βDepression = 0.025, pDepression < 0.01; βAnxiety = 0.022, pAnxiety < 0.01; βStress = 0.022, pStress < 0.01). Primiparity also had a significant influence on the intervention effect regarding depression symptoms (β = 0.033, p = 0.024). Conclusions. Digital mindfulness interventions are a promising method to reduce mental health symptoms in pregnant women. We identified certain parameters moderating this effect, for example, primiparity and the attrition rate.

Digit Ratio (2D:4D) Is Not Associated with Alzheimer's Disease in the Elderly

The development of Alzheimer's disease (AD) is influenced by sex hormones-estrogens and androgens in particular. However, the impact of prenatal sex hormone exposure is less clear; very few investigations have examined the relationship between the second-to-fourth digit length ratio (2D:4D), a putative proxy for the ratio of prenatal estrogens to androgens, and AD, with inconsistent results among the few that have. Therefore, we aimed to investigate this relationship using methodologically robust metrics. In a 2 (sex) × 4 (group) MANOVA incorporating 108 participants (30 AD patients, 19 patients with tauopathy but no amyloidopathy, 31 clinical and 28 healthy age- and education-matched controls), the effects of sex and group on the dependent variables right and left 2D:4D were examined. We also explored the association between 2D:4D and the severity of AD symptoms assessed via neuropsychological examination. We did not find any significant differences in the right- and left-hand 2D:4D between patients with AD and the other groups; no significant associations between 2D:4D and neuropsychological task performances were found in the dementia groups. The 2D:4D of healthy women was significantly lower than that of depressed women without AD, i.e., clinical controls, but not significantly different from depressed female patients with AD. This investigation does not support the role of 2D:4D in the development or severity of AD in general, but suggests a potential role of 2D:4D for depression in women. Future studies are warranted to clarify whether 2D:4D can distinguish between early- and late-onset depression in women.

Sex chromosome and gonadal hormone contributions to binge-like and aversion-resistant ethanol drinking behaviors in Four Core Genotypes mice

Introduction

While substantial research has focused on the contribution of sex hormones to driving elevated levels of alcohol drinking in female rodents, fewer studies have investigated how genetic influences may underlie sex differences in this behavior.

Methods

We used the Four Core Genotypes (FCG) mouse model to explore the contribution of sex chromosome complement (XX/XY) and gonad type [ovaries (Sry-)/testes (Sry+)] to ethanol (EtOH) consumption and quinine-resistant drinking across two voluntary self-administration tasks: limited access consumption in the home cage and an operant response task.

Results

For limited access drinking in the dark, XY/Sry + (vs. XX/Sry +) mice consumed more 15% EtOH across sessions while preference for 15% EtOH vs. water was higher in XY vs. XX mice regardless of gonad type. XY chromosomes promoted quinine-resistant drinking in mice with ovaries (Sry-) and the estrous cycle did not affect the results. In the operant response task, responding for EtOH was concentration dependent in all genotypes except XX/Sry + mice, which maintained consistent response levels across all concentrations (5-20%) of EtOH. When increasing concentrations of quinine (100-500 μM) were added to the solution, FCG mice were insensitive to quinine-punished EtOH responding, regardless of sex chromosome complement. Sry + mice were further found to be insensitive to quinine when presented in water. Importantly, these effects were not influenced by sensitivity to EtOH's sedative effect, as no differences were observed in the time to lose the righting reflex or the time to regain the righting reflex between genotypes. Additionally, no differences in EtOH concentration in the blood were observed between any of the genotypes once the righting reflex was regained.

Discussion

These results provide evidence that sex chromosome complement regulates EtOH consumption, preference, and aversion resistance and add to a growing body of literature suggesting that chromosomal sex may be an important contributor to alcohol drinking behaviors. Examination of sex-specific genetic differences may uncover promising new therapeutic targets for high-risk drinking.

Sex-specific effects of different types of prenatal stress on foetal testosterone levels and NMDA expression in mice

Prenatal stress is a critical life event often resulting in mental illnesses in the offspring. The critical developmental processes, which might trigger a cascade of molecular events resulting in mental disorders in adulthood, are still to be elucidated. Here we proposed that sex hormones, particularly testosterone, might determine the "developmental programming" of long-term consequences of prenatal stress in foetuses of both sexes. We observed that severe prenatal stress in the model of repeated corticosterone injections enhanced brain levels of corticosterone and testosterone in male foetuses. The expression of GluN1 and GluN2A, but not GluN2B NMDA receptor subunits were significantly reduced in the brain of stressed male foetuses. However, female foetuses were protected against stress effects on the brain corticosterone and testosterone levels. More moderate types of stress, such as repeated restraint stress and chronic unpredictable stress, did not induce an increase in brain corticosterone in dams and testosterone concentrations in foetuses of both sexes. Moreover, chronic unpredictable stress reduced brain testosterone concentration in male foetuses. Altogether, changes in brain testosterone level might be one of the crucial mechanisms determining the development of long-term consequences of severe prenatal stress in male, but not in female foetuses. Targeting this mechanism might allow to develop principally new prediction and therapeutic approaches for prenatal stress-associated psychiatric disorders.

Body mass index interacts with sex to predict readmission in in-patients with alcohol use disorder

A previous highly controlled pilot study revealed that body mass index (BMI) predicts outcome of in-patients with alcohol use disorder (AUD) in a sex-specific manner. We here provide translational evidence from a daily clinical routine setting and investigated whether BMI and sex interact to predict 24-month readmission risk in four naturalistic cohorts of a specialized addiction clinic (i.e., all patients admitted to the clinic from 2016 to 2020): (i) in-patients (443 males and 197 females) and (ii) day clinic patients (241 males and 103 females) with a primary diagnosis of AUD; (iii) in-patients (175 males and 98 females) and (iv) day clinic patients (174 males and 64 females) with a primary substance use disorder (SUD) other than alcohol. In the in-patients with AUD, BMI interacted with sex to predict the 24-month readmission risks (p = 0.008; after adjustment for age and liver enzyme activities: p = 0.012); with higher BMI, the risk increases significantly in males, whereas for females, the risk tends to decrease. In the group of overweight in-patients, we found higher readmission rates in males relative to females with an odds ratio of 1.8 (p = 0.038). No such significant effects were found in the other cohorts. This study's findings support previous results, suggesting that the easily accessible BMI may serve as a predictive and sex-sensitive biomarker for outcome in in-patients with AUD. Future studies are necessary to elucidate the underlying aetiopathological mechanisms.

Meta-analytic evidence for a sex-diverging association between alcohol use and body mass index

Alcohol use is an important health issue and has been suggested to contribute to the burden produced by obesity. Both alcohol use and obesity are subject to sex differences. The available studies on the relationship between alcohol use and body mass index (BMI) report inconsistent results with positive, negative, and null findings which requests a meta-analytic approach. Therefore, we conducted a meta-analysis of case-control, cohort, and cross-sectional studies. The systematic literature search and data extraction was performed by 3 independent raters. We conducted sex-separated meta-analyses and -regressions to investigate how alcohol consumption associates with BMI. Our systematic literature search resulted in 36 studies with 48 data sets (Nmen = 172,254; kmen = 30; Nwomen = 24,164; kwomen = 18; Nunknown sex = 672,344; kunknown sex = 24). Alcohol use was associated with higher BMI in men (g = 0.08 [0.07; 0.09]) and lower BMI in women (g = - 0.26 [- 0.29; - 0.22]). Moreover, we found the amount of daily alcohol intake in men (β = 0.001 [0.0008; 0.0014]) and ethnicity in women (g[Caucasians] = - 0.45 versus g[Asians] = - 0.05; z = 11.5, p < 0.0001) to moderate these effects. We here identified sex-diverging relationships between alcohol use and BMI, found daily alcohol intake and ethnicity to sex-specifically moderate these effects, and argue that sex-specific choice of beverage type and higher amount of daily alcohol use in men than in women account for these observations. Future research is needed to provide empirical evidence for the underlying mechanisms.

Neural cue reactivity is not stronger in male than in female patients with alcohol use disorder

BACKGROUND

Males consume more alcohol than females, and alcohol use disorder (AUD) is more prevalent in males than females. However, females progress faster to AUD. Sex differences in neural alcohol cue reactivity were previously observed in young social drinkers, indicating a role of hypersensitivity to alcohol-related cues in very early stages of addiction. To our knowledge, this is the first study on patients diagnosed with AUD to test sex differences in neural reactivity to alcohol cues in order to widen previous findings.

METHODS

We analyzed data from previous studies, using a well-established functional magnetic resonance imaging (fMRI) paradigm to compare neural reactivity to alcohol cues between 42 female and 124 male patients with AUD (mean age 45 and 46 years) in predefined regions of interest that were implicated by previous studies (ventral and dorsal striatum as well as caudate, putamen, amygdala, hippocampus, insula, anterior cingulate cortex, and medial prefrontal cortex) using independent samples t-tests. Post-hoc, effect size calculations were performed.

RESULTS

Throughout all nine regions of interest, we found no statistically significant sex differences in neural reactivity toward alcoholic pictures alone or in comparison to neutral pictures (p > 0.05, FDR-corrected). Post-hoc effect size estimates indicated a magnitude between 0.137 and 0.418 (Hedge's g) on alcohol reactivity to alcohol cues compared to neutral cues and indicate very small to less than medium effect sizes in the direction of higher cue reactivity in female patients.

CONCLUSION

Previous studies showed sex differences in neural alcohol cue reactivity in younger social and problematic alcohol drinkers, i.e., stronger striatal cue-reactivity in males. After correction for multiple comparisons, we did not observe significant sex differences in a cohort of middle-aged females and males with AUD. Sex differences that are present during early phases of addiction development might disappear at later stages of AUD and might thus be considered as clinically less relevant in patients with more severe AUD.

Elevated Oxytocin Receptor Blood Concentrations Predict Higher Risk for, More, and Earlier 24-Month Hospital Readmissions after In-Patient Detoxification in Males with Alcohol Use Disorder

Alcohol use disorder (AUD) is a major global mental health challenge. Knowledge concerning mechanisms underlying AUD and predictive biomarkers of AUD progression and relapse are insufficient. Recently, addiction research is focusing attention on the oxytocin system. However, to our knowledge, blood concentrations of the oxytocin receptor (OXTR) have not yet been studied in AUD. Here, in sex-separated analyses, OXTR serum concentrations were compared between early-abstinent in-patients with AUD (113 men, 87 women) and age-matched healthy controls (133 men, 107 women). The OXTR concentrations were correlated with sex hormone and oxytocin concentrations and alcohol-related hospital readmissions during a 24-month follow-up. In male patients with AUD, higher OXTR concentrations were found in those with an alcohol-related readmission than in those without (143%; p = 0.004), and they correlated with more prospective readmissions (ρ = 0.249; p = 0.008) and fewer days to the first readmission (ρ = −0.268; p = 0.004). In men and women, OXTR concentrations did not significantly differ between patients with AUD and controls. We found lower OXTR concentrations in smokers versus non-smokers in female patients (61%; p = 0.001) and controls (51%; p = 0.003). In controls, OXTR concentrations correlated with dihydrotestosterone (men, ρ = 0.189; p = 0.030) and testosterone concentrations (women, ρ = 0.281; p = 0.003). This clinical study provides novel insight into the role of serum OXTR levels in AUD. Future studies are encouraged to add to the available knowledge and investigate clinical implications of OXTR blood concentrations.

Sulphated dehydroepiandrosterone serum levels are reduced in women with alcohol use disorder and correlate negatively with craving: A sex-separated cross-sectional and longitudinal study

Previous studies have established a role of sex hormones in alcohol use disorder (AUD).Only few clinical investigations with low numbers of patients with AUD have focused on the sulphated form of dehydroepiandrosterone (DHEA-S), despite its function as a neuromodulating sex steroid on receptors in the central nervous system (γ-aminobutyric acid type A, N-methyl-D-aspartate, sigma-1 receptors). DHEA-S serum levels were compared between 200 inpatients with AUD (44% women) admitted for withdrawal treatment and 240 healthy controls (45% women) and analysed longitudinally in patients from early abstinence (baseline) to a median of 5 days later. We also correlated DHEA-S levels with craving, liver enzyme activities, and prospective alcohol-related readmissions during a 24-month follow-up. DHEA-S concentrations were lower in female patients than in female healthy controls during baseline (70%) and decreased from baseline to follow-up in the female and male patients groups (down to: women, 92%; men, 76%). Baseline DHEA-S concentrations correlated with the total and obsessive subscales of the Obsessive-Compulsive Drinking Scale and with maximum visual analogue scale craving scores in female patients (Rho ≤ -0.240) and gamma-glutamyl transferase activity in female (Rho = -0.292) and male (Rho = -0.391) patients. DHEA-S did not significantly predict outcome. We found interactions with smoking behaviour and age. This is the first study based on large cohorts of inpatients with AUD undergoing a qualified detoxification treatment to provide sex-separated evidence for associations of DHEA-S serum concentrations with AUD and related phenotypes. The results stimulate further investigations whether DHEA-S directly influences alcohol craving building a basis to develop sex-sensitive prevention and treatment strategies.

Virtual reality: a powerful technology to provide novel insight into treatment mechanisms of addiction

Due to its high ecological validity, virtual reality (VR) technology has emerged as a powerful tool for mental health research. Despite the wide use of VR simulations in research on mental illnesses, the study of addictive processes through the use of VR environments is still at its dawn. In a systematic literature search, we identified 38 reports of research projects using highly immersive head-mounted displays, goggles, or CAVE technologies to provide insight into treatment mechanisms of addictive behaviors. So far, VR research has mainly addressed the roles of craving, psychophysiology, affective states, cognition, and brain activity in addiction. The computer-generated VR environments offer very realistic, dynamic, interactive, and complex real-life simulations requesting active participation. They create a high sense of immersion in users by combining stereoscopic three-dimensional visual, auditory, olfactory, and tactile perceptions, tracking systems responding to user movements, and social interactions. VR is an emerging tool to study how proximal multi-sensorial cues, contextual environmental cues, as well as their interaction (complex cues) modulate addictive behaviors. VR allows for experimental designs under highly standardized, strictly controlled, predictable, and repeatable conditions. Moreover, VR simulations can be personalized. They are currently refined for psychotherapeutic interventions. Embodiment, eye-tracking, and neurobiological factors represent novel future directions. The progress of VR applications has bred auspicious ways to advance the understanding of treatment mechanisms underlying addictions, which researchers have only recently begun to exploit. VR methods promise to yield significant achievements to the addiction field. These are necessary to develop more efficacious and efficient preventive and therapeutic strategies.

Oxytocin blood concentrations in alcohol use disorder: A cross-sectional, longitudinal, and sex-separated study

Alcohol use disorder (AUD) is a severe illness, for which we lack sufficient mechanistic understanding. Preliminary evidence associates AUD with the oxytocin (OXT) system. Here we investigated alterations in endogenous OXT blood concentrations in patients with AUD and their association with alcohol drinking and prospective course. In sex-separated analyses, OXT serum concentrations of 200 in-patients with AUD (56.5% male; baseline, 24-72 h of abstinence) were compared with those of 240 age-matched healthy controls (55.4% male), investigated longitudinally (follow-up, 5 days later), and tested for associations with alcohol drinking behavior and prospective 24-month alcohol-related hospital readmissions. At baseline, the patients showed increased OXT concentrations relative to controls (men, 156%, P < 0.001; women, 124%, P = 0.002). The elevations normalized at follow-up. In male patients, baseline OXT concentrations correlated positively with alcohol concentration at admission, the amount of alcohol consumption per drinking year, and the number of previous withdrawal treatments (Rho > 0.195, P < 0.044). In beverage type-specific analysis, baseline OXT concentrations correlated with liquor consumption positively in male and negatively in female patients (|Rho| > 0.277, P < 0.017). Higher baseline OXT concentrations predicted more readmissions and fewer days to the first readmission (|Rho| > 0.185, P < 0.050) in male patients. This study provides novel and sex-separated insights into the role of the OXT system in AUD. We identified a mechanism that might underlie the sex-separated choice of beverage type and established that increased OXT concentrations during early abstinence predict a worse outcome in male patients with AUD.

Progesterone serum levels correlate negatively with craving in female postmenopausal in-patients with alcohol use disorder: A sex- and menopausal status-separated study

OBJECTIVE

Alcohol use disorder (AUD) shows a high prevalence and often takes a severe and chronic course. However, the underlying mechanisms still need to be better understood. There is increasing evidence for a role of sex hormones in AUD and for the importance of sex-separated concepts in addiction research. Nevertheless, only few data give insight into how progesterone is involved in AUD.

METHOD

Serum progesterone levels were measured at baseline (during early abstinence) in 186 in-patients with AUD (19% premenopausal females, 20% postmenopausal females, 61% males) and at median 5 days later. They were compared with those of 233 healthy control subjects (24% premenopausal females, 19% postmenopausal females, 57% males). We quantified craving with the Obsessive Compulsive Drinking Scale (OCDS) and visual analogue scales (VAS). Alcohol-related hospital readmissions within a 24-month period following initial in-patient treatment were recorded. We conducted analyses separately for sex and for menopausal status in female participants.

RESULTS

Postmenopausal females with AUD reported higher craving than premenopausal females. In postmenopausal females, higher baseline progesterone levels correlated with lower OCDS total craving and VAS craving, i.e., lower state craving and lower average, maximum, and less frequent craving during withdrawal. In males with AUD, progesterone levels at baseline tended to be higher than in controls and declined to follow-up. Alcohol-related readmissions were not significantly associated with serum progesterone levels.

CONCLUSION

We provide first evidence that progesterone levels correlate with craving in females with AUD.

Acute effects of ethanol on behavioral responses of male and female zebrafish in the open field test with the influence of a non-familiar object

In this report, we investigate whether the acute effects of different ethanol (EtOH) concentrations are sex-dependent in zebrafish subjected to the open field test (OFT) with the influence of a non-familiar object. Male and female zebrafish were separated into four groups and exposed to EtOH (0%, 0.25%, 0.5%, or 1.0% v/v) for 1 h. Fish were tested individually in the OFT, in which tank was divided into three areas: periphery, intermediate, and center area. An object (black sphere; diameter: 1 cm) was placed in the center of the tank and behaviors were recorded for 5 min. At the baseline, females had a distinct exploratory activity and interaction pattern with the object, reflecting a more anxious and shyer behavior in relation to males. Females exposed to 0.5% EtOH performed more rapid investigation to the object than males, while 1.0% EtOH reduced locomotion in both sexes and increased immobility only in males. Principal component analyses revealed that anxiety-like behaviors, exploratory activity, and locomotion were the components that most accounted for total variances. Collectively, our novel findings show the existence of a sex-dependent effect in the zebrafish models acutely exposed to EtOH tested in the OFT with a non-familiar object.

Prevalence and risk factors associated with alcohol consumption among indigenous people in Sabah Borneo Island

OBJECTIVES

In this study, we aimed to determine the prevalence and risk factors of alcohol use among a cohort of population in Sabah.

DESIGN

This is a prospective, cohort study involving rural community residents.

SETTING

Rural community resident at Bingkor, Keningau, Sabah.

PARTICIPANTS

363 individuals aged 13 years old and above.

INTERVENTION

Community-based participatory research to determine the prevalence and risk factors associated with alcohol use.

MAIN OUTCOME MEASURES

Measurement of alcohol use using Alcohol Use Disorders Identification Test (AUDIT) and assessment of psychiatric morbidity using Mini International Neuropsychiatric Interview (MINI) questionnaires.

RESULTS

Most alcohol drinkers aged between 36-45 years old, followed by 26-35 years old and 46-55 years old. Interestingly, there are almost similar female to male ratio. Most were Kadazan-Dusun ethnic, non-Muslims, and married. Although only less than a third of the participants received tertiary education, the majority were working. Based on the findings, being a male, non-Muslim and having an obsessive-compulsive disorder (OCD) (current) posed a significantly higher risk of alcohol consumption.

CONCLUSION

A worryingly high prevalence of hazardous alcohol consumption among the locals is reported. There is a need for population-wide intervention towards preventive measures based on the identified risk factors for hazardous alcohol use.

Body mass index and serum levels of soluble leptin receptor are sex-specifically related to alcohol binge drinking behavior

OBJECTIVE

Binge drinking is a highly prevalent behavior in adolescents and young adults and a risk factor to develop alcohol use disorder. Body mass index (BMI) and blood levels of leptin peptide and its soluble receptor have been implicated in alcohol use disorder; however, their role in binge drinking remains to be investigated.

METHOD

We studied associations of BMI, serum levels of soluble leptin receptor (ObRe) and leptin as well as the free leptin index with binge drinking in 93 male and 99 female young adults.

RESULTS

In men, binge drinkers showed significantly higher BMI (kg/m²) than non-binge drinkers (23.67 vs. 22.08) and higher BMI correlated significantly with more severe binge drinking episodes (ρ = 0.251). In women, we found significantly higher ObRe (ng/ml) / BMI (kg/m²) values in binge drinkers than in non-binge drinkers (0.52 vs. 0.44) and ObRe/BMI values correlated significantly with more severe binge drinking episodes (ρ = 0.210).

CONCLUSION

This study confirms that higher BMI associates with binge drinking in men and shows for the first time a role of ObRe/BMI in binge drinking in women. Our data emphasize the importance of further research in the field of metabolic markers and implications in neurobiological processes of binge drinking.

Recent Perspectives on Sex Differences in Compulsion-Like and Binge Alcohol Drinking

Alcohol use disorder remains a substantial social, health, and economic problem and problem drinking levels in women have been increasing in recent years. Understanding whether and how the underlying mechanisms that drive drinking vary by sex is critical and could provide novel, more targeted therapeutic treatments. Here, we examine recent results from our laboratories and others which we believe provide useful insights into similarities and differences in alcohol drinking patterns across the sexes. Findings for binge intake and aversion-resistant, compulsion-like alcohol drinking are considered, since both are likely significant contributors to alcohol problems in humans. We also describe studies regarding mechanisms that may underlie sex differences in maladaptive alcohol drinking, with some focus on the importance of nucleus accumbens (NAcb) core and shell regions, several receptor types (dopamine, orexin, AMPA-type glutamate), and possible contributions of sex hormones. Finally, we discuss how stressors such as early life stress and anxiety-like states may interact with sex differences to contribute to alcohol drinking. Together, these findings underscore the importance and critical relevance of studying female and male mechanisms for alcohol and co-morbid conditions to gain a true and clinically useful understanding of addiction and neuropsychiatric mechanisms and treatment.

Markers of Prenatal Androgen Exposure Correlate With Online Sexual Compulsivity and Erectile Function in Young Men

Pornography addiction and sexual dysfunction are increasingly prevalent in young men. Previous studies suggest that prenatal androgen exposure plays a role in addiction and sexual functionality. Here, we tested whether lower second-to-fourth finger length ratio (2D:4D) and later age at spermarche, both putative indicators of higher androgen levels in utero, correlate with online sexual compulsivity (OSC scale of ISST), erectile function (IIEF-5), and ejaculatory control (PEPA) in 4,370 young men (age IQR: 25-26 years) of the Cohort Study on Substance Use Risk Factors. Statistical analyses revealed that lower 2D:4D correlated with higher scores on the OSC scale. Moreover, higher age at spermarche correlated with higher OSC scores and decreased erectile function. Interestingly, OSC severity, but not the frequency of pornography use, correlated negatively with erectile function and ejaculatory control. This is the first study to associate two independent proxies of prenatal testosterone level with OSC. These findings provide novel insight into intrauterine predisposition of sexual behavior and related sexual function in adulthood.

Evaluation of the German biographic screening interview for fetal alcohol spectrum disorder (BSI-FASD)

Alcohol consumption during pregnancy may lead to permanent damage in the offspring, including fetal alcohol spectrum disorders (FASD), which have an estimated prevalence of 1-8% worldwide. In adulthood, diagnosing FASD is time-consuming and costly. This study aimed to evaluate the discriminatory power of a German screening instrument for FASD in adults-the biographic screening interview (BSI-FASD). In an open-label comparative cohort study wherein a one-time survey was administered per participant, we compared 22 subjects with confirmed FASD with control groups of 15 subjects diagnosed with attention deficit hyperactivity disorder (ADHD), 20 subjects with alcohol or opiate dependence, 18 subjects with depression, and 31 controls without prenatal alcohol exposure. The BSI-FASD was found to be resource-efficient, user-friendly, comprehensible, and easily applicable. It provided an overall good convergent and discriminant validity with a sensitivity of 0.77 (adapted 0.86) and specificities between 0.70 and 1.00. The BSI-FASD subdomains differed in their power to differentiate FASD from the groups. This study established that the BSI-FASD is an efficient instrument to screen adults with suspected FASD. The BSI-FASD may facilitate future diagnostic evaluation and thereby contribute to improved treatment of affected individuals.

Tissue-specific transcriptome recovery on withdrawal from chronic alcohol exposure in zebrafish

Alcohol consumption can lead to a wide range of systemic disorders brought about by transcriptional changes. Recent studies have documented altered behavior and physiology in zebrafish exposed to alcohol. In this work, we have identified the changes in the zebrafish transcriptome in response to chronic alcohol exposure. We have further followed the extent of transcriptional recovery upon withdrawal from alcohol and found evidence of tissue-specific responses. Our results indicate a greater extent of recovery of the brain transcriptome compared to the liver. We identify two distinct classes of genes in response to withdrawal from alcohol exposure - those that recover their pre-alcohol expression profile versus those that retain altered expression even after the fish are removed from the alcohol environment. Finally, we have examined gender-specific responses to alcohol exposure in zebrafish and find evidence for distinct alcohol tolerance levels. Upon chronic alcohol exposure, a higher percentage of genes show perturbation in expression profile in males compared to females. Female fish also recover better with more genes regaining the control expression level upon withdrawal from alcohol. Overall, our work identifies genes and pathways perturbed by exposure to alcohol, and demonstrates the extent of gender- and tissue-specific transcriptional changes associated with chronic alcoholism and withdrawal.

Sex differences in progestogen- and androgen-derived neurosteroids in vulnerability to alcohol and stress-related disorders

Stress and trauma exposure disturbs stress regulation systems and thus increases the vulnerability for stress-related disorders which are characterized by negative affect, including major depressive disorder, anxiety disorders and posttraumatic stress disorder. Similarly, stress and trauma exposure results in increased vulnerability to problematic alcohol use and alcohol use disorder, especially among women, who are more likely to drink to cope with negative affect than their male counterparts. Given these associations, the relationship between stress-related disorders and alcohol use is generally stronger among women leading to complex comorbidities across these disorders and alcohol misuse. This review highlights the therapeutic potential for progestogen- and androgen-derived neurosteroids, which affect both stress- and alcohol-related disorders, to target the overlapping symptoms related to negative affect. This article is part of the special issue on 'Vulnerabilities to Substance Abuse.'

Ovarian Hormones and Reward Processes in Palatable Food Intake and Binge Eating

Ovarian hormones are associated with risk for binge eating in women. Recent animal and human studies suggest that food-related reward processing may be one set of neurobiological factors that contribute to these relationships, but additional studies are needed to confirm and extend findings.

Evaluating the genetic effects of sex hormone traits on the development of mental traits: a polygenic score analysis and gene-environment-wide interaction study in UK Biobank cohort

OBJECTIVE

To evaluate the genetic effects of sex hormone traits on the development of mental traits in middle-aged adults.

METHODS

The SNPs associated with sex hormone traits were derived from a two-stage genome-wide association study (GWAS). Four sex hormone traits were selected in the current study, including sex hormone-binding globulin (SHBG), testosterone, bioavailable testosterone and estradiol. The polygenic risk score (PRS) of sex hormone traits were calculated from individual-level genotype data of the United Kingdom (UK) Biobank cohort. We then used logistic and linear regression models to assess the associations between individual PRS of sex hormone traits and the frequency of alcohol consumption, anxiety, intelligence and so on. Finally, gene-environment-wide interaction study (GEWIS) was performed to detect novel candidate genes interacting with the sex hormone traits on the development of fluid intelligence and the frequency of smoking and alcohol consumption by PLINK2.0.

RESULTS

We observed positive association between SHBG and the frequency of alcohol consumption (b = 0.0101, p = 3.84 × 10-11) in middle-aged males and females. In addition, estradiol was positively associated with the frequency of alcohol consumption (b = 0.0128, p = 1.96 × 10-8) in middle-aged males. Moreover, bioavailable testosterone was associated with the fluid intelligence (b = - 0.0136, p = 5.74 × 10-5) in middle-aged females. Finally, GEWIS identified one significant loci, Tenascin R (TNR) (rs34633780, p = 3.45 × 10-8) interacting with total testosterone for fluid intelligence.

CONCLUSION

Our study results support the genetic effects of sex hormone traits on the development of intelligence and the frequency of alcohol consumption in middle-aged adults in UK.

Features of neurosteroid support of the state of alcohol dependence and its correction with dosed physical load in rats

The role of steroid hormones in regulation of the functions of the emotiogenic limbic-neocortical system has been actively studied over the recent decades in order to determine their synthesis in the brain structures and role in the development and maintenance of dependence on psychoactive substances. However, the wide range of neurosteroids and their metabolites, as well as structural specific features of the synthesis of both neurohormones and their receptors make it difficult to obtain experimental data and interpret the results of the study. The participation of progesterone, cortisol, testosterone and estradiol in the development of alcohol dependence and the changes in their concentrations in the hypothalamus, hippocampus, amygdala and serum under the influence of dosed physical load were studied in 48 outbred adult male rats. Alcohol dependence was modeled by means of consuming food containing alcohol in the dose of 1.25 g of ethanol per 1 kg of rat body weight for two months. Dosed physical load was reproduced by a rat running in a wheel for 30 minutes daily for 7–10 days against the background of alcohol withdrawal. Neuroethological testing of craving for alcohol, EEG recording of the neocortex, hippocampus and amygdala was performed using a computer-diagnostic complex. The concentration of steroid hormones was determined in the structures of the brain and blood serum by the enzyme-linked immunosorbent assay. It was shown that dosed physical load attenuated the alcohol motivation of rats. On the 5th day it suppressed the electrographic manifestations of paroxysmal activity in the hippocampus and increased the level of the theta-rhythm in the amygdala, and on the 7th day it activated the neocortex with increasing beta-rhythm. This effect was accompanied by an increase in serum testosterone level against the background of maintaining functional tension of the peripheral glucocorticoid link of the hypothalamus-pituitary-adrenal system, which was observed in a state of alcohol dependence. The study demonstrated that progesterone plays the key role in allostatic rearrangements of the functional state of animals. An imbalance of progesterone levels was revealed in the brain structures: an increase – in the hypothalamus and hippocampus, and a decrease – in the amygdala under alcohol dependence; a decrease – in the hippocampus with recovery in the amygdala against the background of its high level in the hypothalamus, which occurs under the influence of dosed physical load on the rats under alcohol withdrawal. Thus, the dosed physical load is a promising approach to alcohol dependence rehabilitation.

Effectiveness of a mindfulness-oriented substance use prevention program for boys with mild to borderline intellectual disabilities: study protocol for a randomised controlled trial

BACKGROUND

Boys with mild to borderline intellectual disabilities (MBID) are at particular risk to drink in harmful ways once they start to consume alcohol. Interventions based on mindfulness have been proven to be effective in preventing substance use, but mostly for adults with MBID. A mindfulness oriented intervention targeting 11-17 years old boys will be tested in a randomised controlled trial. Study aim is to investigate the benefits of this new intervention compared to an active control condition within a 12 months follow-up.

METHODS

In this randomised controlled proof of concept study, 82 boys with MBID who consumed any alcohol during the last year will be randomised either to the 6 week mindfulness oriented intervention or the control group receiving a control intervention equal in dose and length. The intervention group undergoes mindfulness training combined with interactive drug education, while the control group completes a health training combined with the same education. In the intention-to-treat analysis the primary outcome is the self-reported delay of first post-intervention drunkeness within a 12 months follow-up time span, measured weekly with a short app-based questionnaire. Secondary outcome is the use of alcohol, tobacco and other drugs within 30 days post-intervention. Changes in neurobiological behavioural parameters, such as impulse control, reward anticipation, and decision making, are also investigated. Other secondary outcomes regard trait mindfulness, emotion regulation, psychopathological symptoms, peer networks, perceived stress, and quality of life. In addition, a prospective registry will be established to record specific data on the population of 11-17 year old boys with MBID without any alcohol experience.

DISCUSSION

This study offers the opportunity to gain first evidence of the effectiveness of a mindfulness-oriented program for the prevention of substance use for boys with MBID.

TRIAL REGISTRATION

German Clinical Trials Register, DRKS00014042 . Registered on March 19th 2018.

Digit ratio (2D:4D) and transgender identity: new original data and a meta-analysis

Previously reported associations between second-to-fourth digit length ratio (2D:4D), a proxy for prenatal androgen load, and transgender identity have been inconsistent. The objectives of the present study were to provide additional original data and an updated meta-analysis concerning this association. In a study of 464 participants, we compared the 2D:4D of transgender individuals with age- and sex-matched controls. Patients were recruited at a specialized psychiatrist's medical office, whereas controls were hired via flyers, advertisements, and as convenience sample. A random-effects meta-analysis of the literature (17 samples, n = 3674) also quantifies the overall magnitude of the difference in 2D:4D between transgender individuals and controls. In our study providing new original data, we found a significantly higher (i.e. feminized) left-hand 2D:4D in the male-to-female transgender (MtF) identity [mean age: 32.3 (18; 61)] than in the male control group [mean age: 34.5 (18; 65)] with a Cohen's d = 0.271. Concordantly, the meta-analytic results suggest a significant difference in 2D:4D among MtF individuals compared to male controls [g = 0.153; 95% CI (0.063; 0.243)], which was even more pronounced when individuals had been diagnosed by a clinician instead of self-identified as transgender [g = 0.193; 95% CI (0.086; 0.300)]. In both studies, no significant results were revealed for female-to-male transgender individuals [mean age: 26.1 (18; 53)] versus female controls [mean age: 27.2 (18; 55)]. This original investigation and the updated meta-analysis clarify the association between transgender identity and 2D:4D indicating the influence of prenatal androgen on the development of gender identity in subjects born as males.

Type 1 equilibrative nucleoside transporter (ENT1) regulates sex-specific ethanol drinking during disruption of circadian rhythms

Disruptions in circadian rhythms are risk factors for excessive alcohol drinking. The ethanol-sensitive adenosine equilibrative nucleoside transporter type 1 (ENT1, slc29a1) regulates ethanol-related behaviors, sleep, and entrainment of circadian rhythms. However, the mechanism underlying the increased ethanol consumption in ENT1 knockout (KO) mice in constant light (LL) and whether there are sex differences in ethanol consumption in ENT1 mice are less studied. Here, we investigated the effects of loss of ENT1, LL, and sex on ethanol drinking using two-bottle choice. In addition, we monitored the locomotor activity rhythms. We found that LL increased ethanol drinking and reduced accumbal ENT1 expression and adenosine levels in male but not female mice, compared with control mice. Interestingly, only LL-exposed male, not female, ENT1 KO mice exhibited higher ethanol drinking and a longer circadian period with a higher amplitude compared with wild-type (WT) mice. Furthermore, viral-mediated rescue of ENT1 expression in the NAc of ENT1 KO mice reduced ethanol drinking, demonstrating a possible causal link between ENT1 expression and ethanol drinking in males. Together, our findings indicate that deficiency of ENT1 expression contributes to excessive ethanol drinking in a sex-dependent manner.

Clinical outcomes and characteristics of P30L mutations in congenital adrenal hyperplasia due to 21-hydroxylase deficiency

Despite numerous studies in the field of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, some clinical variability of the presentation and discrepancies in the genotype/phenotype correlation are still unexplained. Some, but not all, discordant phenotypes caused by mutations with known enzyme activity have been explained by in silico structural changes in the 21-hydroxylase protein. The incidence of P30L mutation varies in different populations and is most frequently found in several Central and Southeast European countries as well as Mexico. Patients carrying P30L mutation present predominantly as non-classical CAH; however, simple virilizing forms are found in up to 50% of patients. Taking into consideration the residual 21-hydroxulase activity present with P30L mutation this is unexpected. Different mechanisms for increased androgenization in patients carrying P30L mutation have been proposed including influence of different residues, accompanying promotor allele variability or mutations, and individual androgene sensitivity. Early diagnosis of patients who would present with SV is important in order to improve outcome. Outcome studies of CAH have confirmed the uniqueness of this mutation such as difficulties in phenotype classification, different fertility, growth, and psychologic issues in comparison with other genotypes. Additional studies of P30L mutation are warranted.

The Endocrine System and Alcohol Drinking in Females

Sexually dimorphic effects of alcohol exposure throughout life have been documented in clinical and preclinical studies. In the past, rates of alcohol use disorder (AUD) were higher in men than in women, but over the past 10 years, the difference between sexes in prevalence of AUD and binge drinking has narrowed. Recent evidence adds to historical data regarding the influence of sex steroids on alcohol drinking and the interaction with stress-related steroids. This review considers the contribution of the endocrine system to alcohol drinking in females, with a focus on the hypothalamic pituitary gonadal axis and the hypothalamic pituitary adrenal axis and their reciprocal interactions. Emphasis is given to preclinical studies that examined genomic and rapid membrane effects of estrogen, progesterone, glucocorticoids, and GABAergic neurosteroids for their effects on alcohol drinking and models of relapse. Pertinent comparisons to data in males highlight divergent effects of sex and stress steroids on alcohol drinking and emphasize the importance of considering sex in the development of novel pharmacotherapeutic targets for the treatment of AUD. For instance, pharmacological strategies targeting the corticotropin releasing factor and glucocorticoid receptor systems may be differentially effective in males and females, whereas strategies to enhance GABAergic neurosteroids may represent a biomarker of treatment efficacy in both sexes.

The effects of early life adversity on growth, maturation, and steroid hormones in male and female rats

Early life adversity is a risk factor for psychiatric disorders, yet the mechanisms by which adversity increases this risk are still being delineated. Here, we used a limited bedding and nesting (LBN) manipulation in rats that models a low resource environment to examine effects on growth, developmental milestones, and endocrine endpoints. In LBN, dams and pups, from pups' postnatal days 2-9, are exposed to an environment where dams lack proper materials to build a nest. This manipulation is compared to control housing conditions, where rat dams have access to ample nesting materials and enrichment throughout pups' development. We found that the LBN condition altered maternal care, increasing pup-directed behaviors while reducing self-care. This, perhaps compensatory, increase in nursing and attention to pups did not mitigate against changes in metabolism, as LBN reduced weight gain in both sexes and this effect persisted into adulthood. Although adult stress hormone levels in both sexes and vaginal opening and estrous cycle length in females were not disrupted, there was other evidence of endocrine dysregulation. Compared to controls, LBN rats of both sexes had shortened anogenital distances, indicating reduced androgen exposure. LBN males also had higher plasma estradiol levels in adulthood. This combination of results suggests that LBN causes a demasculinizing effect in males that could contribute to lasting changes in the brain and behavior. Importantly, alterations in metabolic and endocrine systems due to early life adversity could be one mechanism by which stress early in life increases risk for later disease.

Lower digit ratio (2D:4D) in alcohol dependence: Confirmation and exploratory analysis in a population-based study of young men

Moderately sized, case-control studies have related alcohol dependence in middle-aged in-patients to lower second-to-fourth finger length ratio (2D:4D), a proxy for prenatal hyperandrogenization. As primary aim, we here intended to confirm that lower 2D:4D is also associated with Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV/-5 alcohol dependence and alcohol use disorder in a large population-based cohort of young males. Exploratory aims included underlying mechanisms. We analyzed self-reported data on 2D:4D, DSM-IV/-5 criteria, anticipated subjective responses to alcohol, and willingness to purchase alcoholic drinks from 4989 Swiss men of the Cohort Study on Substance Use Risk Factors (C-SURF). The mean of right-hand 2D:4D and left-hand 2D:4D was lower in men with DSM-IV alcohol dependence than in those without (0.975 vs 0.981, P = .035) and lower in men with moderate to severe (0.974) than in those with mild (0.982, P = .001) or no (0.981, P = .003) DSM-5 alcohol use disorder. Moreover, mean 2D:4D was lower in those reporting recent use of health services due to substance use problems (0.968 vs 0.981, P = .046). Lower mean 2D:4D correlated with a stronger anticipation to feel high following alcohol consumption (total cohort: ρ = -0.033, P = .026) and with a willingness to purchase more higher-priced alcoholic drinks (DSM-IV alcohol dependence subgroup: ρ_min = -0.162, P = .002). This is the first population-based study on young males to demonstrate lower 2D:4D in DSM-IV alcohol dependence, DSM-5 alcohol use disorder, and the related use of health care services. We also provide novel insight into cognitive-behavioral mechanisms. These results should help to establish more effective preventive and therapeutic strategies targeting 2D:4D and prenatal androgen exposure.

Hormonal responses in gambling versus alcohol abuse: A review of human studies

The endocrine system plays an essential role in communication between various organs of the body to maintain homeostasis. Both substance use disorders (SUDs) and non-substance abuse disrupt this system and lead to hormonal dysregulations. Here, we focus on the comparison between the function of the endocrine system in gambling disorders and alcohol addiction to understand the commonalities and differences in their neurobiological and psychological underpinnings. We review human research to compare findings on gambling addiction and alcohol dependence pertaining to the dynamic interplay between testosterone and cortisol. Understanding and classifying similarities in hormonal responses between behavioural addiction and SUDs may facilitate development of treatments and therapeutic interventions across different types of addictive disorders, while describing differences may shed light on therapeutic interventions for specific disorders. Although research on gambling addiction is in its infancy, such evaluation may still have a positive effect for addiction research, thereby stimulating discovery of "crossover" pharmacotherapies with benefits for both SUDs and nonsubstance addictions.

Gender-affirming hormone treatment - A unique approach to study the effects of sex hormones on brain structure and function

Investigating the effects of the gender-affirming hormone treatment of transgender people using neuroimaging provides a unique opportunity to study the impact of high dosages of sex hormones on human brain structure and function. This line of research is of relevance from a basic neuroscientific as well as from a psychiatric viewpoint. Prevalence rates, etiopathology, and disease course of many psychiatric disorders exhibit sex differences which are linked to differences in sex hormone levels. Here, we review recent neuroimaging studies from others and our group that investigate the effects of gender-affirming hormone treatment in a longitudinal design utilizing structural and functional magnetic resonance imaging and positron emission tomography. Studies point to a general anabolic and anticatabolic effect of testosterone on grey and white matter structure, whereas estradiol and antiandrogen treatment seems to have partly opposite effects. Moreover, preliminary research indicates that gender-affirming hormone treatment influences serotonergic neurotransmission, a finding that is especially interesting for psychiatry. A clear picture of a hormonal influence on brain activity has yet to emerge. In conclusion, the available evidence reviewed here clearly indicates that sex hormone applications influence brain structure and function in the adult human brain.

Serum lipids, leptin, and soluble leptin receptor in alcohol dependence: A cross-sectional and longitudinal study

OBJECTIVE

Alcohol dependence affects metabolic processes. Further research is needed to apply this knowledge clinically. In this study, possible differences in serum lipids and/or leptin activities between alcohol-dependent in-patients and healthy controls and possible associations with alcohol-related blood parameters and with prospective outcomes in alcohol dependence were assessed sex-specifically.

METHOD

We measured and compared (median) serum lipids (triglycerides and total, HDL, and LDL cholesterol) and leptin activities (leptin, soluble leptin receptor [ObRe], and free leptin index) in 200 (males 56.5 %) early-abstinent alcohol-dependent in-patients and 240 (males 55.4 %) healthy controls and assessed alcohol-related readmissions during a 24 -month post-inclusion period.

RESULTS

Male patients showed higher HDL cholesterol (61 versus 48 mg/dl), lower LDL/HDL ratios (2.06 versus 3.04), and lower free leptin index (0.30 versus 0.59) at study inclusion compared to healthy controls. In patients, ObRe levels were higher than in controls and decreased from inclusion to the second study-visit (at median 5 days later; males: 16.7-13.8 versus 11.0 ng/ml; females: 17.0-13.4 versus 12.1 ng/ml). The free leptin index increased between the two time points in females (0.80 versus 1.20). Lipids and leptin activities correlated with carbohydrate-deficient transferrin levels and liver enzyme activities. None of the serum parameters were significantly associated with alcohol-related readmissions.

CONCLUSION

Our data support that serum lipid levels and leptin activities are involved in alcohol dependence. The parameters appear as possible indirect biomarkers for alcohol dependence.

Everything you always wanted to know about sex and dopamine, but were afraid to ask: An Editorial for 'No basal or drug-induced sex differences in striatal dopaminergic levels: a cluster and metaanalysis of rat microdialysis studies' on page 482

Behavioral neuroscience has taken a long time to finally recognize that the largely distinct behavioral repertoires of males and females may arise from differences in brain function. This may in particular apply for the neurochemistry of the dopamine systems and their roles in the organization of emotion, learning, and reinforcement in health and in pathological conditions. The current Editorial highlights a study by Egenrieder and colleagues published in the current issue of the Journal of Neurochemistry, in which the authors have analyzed extracellular dopamine neurochemistry from females and males in a meta-analysis. Largely surprising, they report that after detailed control of methodological differences between studies, no major differences in basal or drug-induced extracellular dopamine activity emerged between sexes in rodents. The locally dissociating effects of ovariectomy in females reported in the Egenrieder et al. study, may furthermore suggest that there may be different sex effects in the distinct dopaminergic projections of the mesolimbic and nigrostriatal dopamine system. However, this may only be the beginning of a system's analysis of dopaminergic sex differences that calls for further meta-analyses of the existing studies.

Basic Human Body Dimensions Relate to Alcohol Dependence and Predict Hospital Readmission

Alcohol dependence is a severe mental illness and there is a need for more effective preventive and therapeutic strategies. Translational research suggests that intrauterine sex hormone exposure modulates the risk and course of alcohol dependence during adulthood. During development, sex hormones permanently shape sexually dimorphic body dimensions. Thus, these dimensions may provide insight into sex hormone organization. Here, we compared body measurements (absolute, relative to, and residualized on height) between 200 alcohol-dependent in-patients and 240 age-matched healthy control subjects and investigated how these measurements associate with the patients' prospective 12- and 24-month outcome. The results show that alcohol dependence is related to lower absolute, relative, and residualized body measurements for height and weight, head circumference, bitragion head arc, lip-chin distance, hip, thigh, and calf circumference, and foot length and breadth. In male alcohol-dependent in-patients, higher risk, shorter latency, and more alcohol-related readmissions were predicted by higher absolute, relative, and residualized thigh and calf circumferences. The second-to-fourth finger length ratio, a putative proxy for prenatal sex hormone organization, was not convincingly correlated with the body dimensions, suggesting that the results represent pubertal (or later) effects. The study's findings have implications for further research. The body measurements' high accessibility may facilitate the future transition into clinical settings.

Nicotine and alcohol: the role of midbrain dopaminergic neurons in drug reinforcement

Nicotine and alcohol addiction are leading causes of preventable death worldwide and continue to constitute a huge socio-economic burden. Both nicotine and alcohol perturb the brain's mesocorticolimbic system. Dopamine (DA) neurons projecting from the ventral tegmental area (VTA) to multiple downstream structures, including the nucleus accumbens, prefrontal cortex, and amygdala, are highly involved in the maintenance of healthy brain function. VTA DA neurons play a crucial role in associative learning and reinforcement. Nicotine and alcohol usurp these functions, promoting reinforcement of drug taking behaviors. In this review, we will first describe how nicotine and alcohol individually affect VTA DA neurons by examining how drug exposure alters the heterogeneous VTA microcircuit and network-wide projections. We will also examine how coadministration or previous exposure to nicotine or alcohol may augment the reinforcing effects of the other. Additionally, this review briefly summarizes the role of VTA DA neurons in nicotine, alcohol, and their synergistic effects in reinforcement and also addresses the remaining questions related to the circuit-function specificity of the dopaminergic system in mediating nicotine/alcohol reinforcement and comorbidity.

Enhanced Alcohol Preference and Anxiolytic Alcohol Effects in Niemann-Pick Disease Model in Mice

Major depression and alcohol use disorder are severe psychiatric diseases affecting the world's population with high comorbidity level. However, the pathogenesis of this comorbidity remains unclear, and no selective treatment for this condition is available. A pathogenic pathway and a possible therapeutic target for the treatment of depression-alcoholism comorbidity based on the hyperfunction of acid sphingomyelinase (Asm) were recently suggested. Here we analyzed the effects of alcohol on the depression/anxiety state of homozygous Asm-knockout mice (Asm − /−), which can be considered as a model of an early stage of Niemann-Pick disease, as well as their drinking pattern under normal and stress conditions. It was observed that forced treatment with alcohol (2 g/kg, i.p.) reduces the anxiety level of Asm−/− mice as measured in the elevated plus maze (EPM) test, but enhances the depression level in the forced swim test (FST). The analysis of drinking pattern of these animals in a free-choice alcohol drinking paradigm revealed higher alcohol intake and preference in Asm−/− mice compared to wild type (wt) littermates. However, this difference was overwritten by the stress exposure. Stronger sedating effects of alcohol were observed in Asm−/− mice compared to wt animals in the loss of righting reflex test after single and repeated alcohol injections (3 g/kg, i.p.). Altogether, the present findings might indicate an Asm involvement in the mechanisms of comorbidity between alcoholism and anxiety/depression.

Estrogen receptor 1 gene variants and estradiol activities in alcohol dependence

OBJECTIVE

Alcohol use disorders inflict a great individual and societal burden. Although sex hormone effects have been implicated in alcohol dependence, research has mostly neglected estrogen activities and female alcohol-dependent patients. Here, we investigated associations of estrogen receptor 1 (ESR1) genetics and serum estradiol activities with aspects of alcohol dependence.

METHOD

Serum estradiol activities of early-abstinent alcohol-dependent in-patients (n[♂] = 113, n[♀] = 87) were followed for at median 5 days and compared with healthy controls (n[♂] = 133, n[♀] = 107). All participants were genotyped for five ESR1 single nucleotide polymorphisms (rs6902771, rs11155819, rs6557171, rs2982683, rs2982712).

RESULTS

Bioavailable estradiol levels decreased during withdrawal treatment (P[♂] < .001, P[♀] = .011). Male patients with an increase of bioavailable estradiol during withdrawal showed fewer days to (P = .033) and more alcohol-related readmissions (P < .05) during the 12-month follow-up. Higher estradiol and estradiol-to-testosterone activities were significantly related to liver, muscle, and cell count damage in male patients. Estradiol-to-testosterone activities in female patients were lower compared to female controls (total P = .013, bioavailable P = .009). Moreover, the ESR1 genotypes jointly separated alcohol-dependent patients from controls (P = .037).

CONCLUSION

Our findings support the role of ESR1 genetics in alcohol dependence and show for the first time that estradiol activities may sex-specifically predict alcohol-related sequelae and outcome following in-patient withdrawal treatment.

Digit ratio (2D:4D) in relation to substance and computer use: a meta-analysis

Human studies have reported inconsistent associations between the length ratio of the second finger to the fourth finger (2D:4D), which is a proxy for prenatal androgen load, and substance or computer use in adolescents and adults. This meta-analysis quantifies the magnitude of this relationship and investigates the roles of sex, definition of caseness, different forms of addiction, the hand measured (right hand versus left hand), and other cohort characteristics. Univariate random-effects meta-analyses were performed, and moderators were tested with Bonferroni-corrected meta-regression analyses. The study included 18 independent samples with a total of 175,955 participants (96,316 males and 79,639 females). There was a significant difference in 2D:4D between the substance and computer-using subjects and the controls for the combined sample (Hedge's g = - 0.178 [- 0.291; - 0.064]) and for males (Hedge's g = - 0.260 [- 0.399; - 0.122]), but not for females. These effects were amplified when only analyzing studies that compared dependent versus non-dependent subjects (combined sample: g = - 0.325 [- 0.492; - 0.157]; males: g = - 0.427 [- 0.564; - 0.291]), but did not reach significance in the subgroup of studies examining other parameters of substance and computer use. When analyzing different forms of substance and computer use separately, alcohol intake and computer use revealed a significant difference in the standardized mean. Again, the effects were amplified when analyzing the subgroup of males and the subgroup of studies comparing dependent versus non-dependent subjects, with effect sizes showing Hedge's g values as many as - 0.552 [- 0.785; - 0.319] (alcohol-dependent males). Thus, this meta-analysis confirms that lower 2D:4D is associated with substance and computer dependency. Further studies are encouraged to explore the link between intrauterine hormone environment and addiction risk.

Crossed Eye/Hand Laterality and Left-Eyedness Predict a Positive 24-Month Outcome in Alcohol-Dependent Patients

BACKGROUND

Available predictors of hospital readmission following withdrawal in alcohol-dependent patients are limited. However, such parameters are needed to optimize individualized treatment strategies. This study investigated whether crossed eye/hand laterality, eyedness, and handedness may predict outcomes in alcohol dependence.

METHODS

The prospective study included 200 early-abstinent alcohol-dependent inpatients (n[males] = 113, n[females] = 87) and 240 control subjects (n[males] = 133, n[females] = 107). We assessed eyedness and handedness using the hole-in-the-card and Shimizu tests and documented alcohol-related readmissions over 12 and 24 months.

RESULTS

Crossed eye/hand laterality and left-eyedness were associated with a reduced risk for alcohol-related readmission (12-month: odds ratios [OR] = 0.41, p = 0.008, OR = 0.42, p = 0.004; 24-month: OR = 0.57, p = 0.097, OR = 0.47, p = 0.016), fewer median readmissions (12-month: 0 vs. 1, p = 0.005, 0 vs. 1, p = 0.005; 24-month: 1 vs. 2, p = 0.014, 1 vs. 2, p = 0.006), and more mean days to the first readmission (12-month: 270 vs. 209, p = 0.007, 269 vs. 207, p = 0.003; 24-month: 462 vs. 335, p = 0.039, 461 vs. 323, p = 0.005). They also interacted with treatment and alcohol drinking history to predict the outcome. In sex-specific analyses, most of these effects remained significant in males but not in females. Handedness alone did not significantly predict outcome. Moreover, the laterality markers did not significantly differ between alcohol-dependent patients and control subjects.

CONCLUSIONS

Determining crossed eye/hand laterality and eyedness may help to individualize relapse prevention in the future. Both are easily accessible predictors of alcohol-related readmission following inpatient withdrawal treatment.