Short-chain fatty acid valerate reduces voluntary alcohol intake in male mice.

BACKGROUND: Despite serious health and social consequences, effective intervention strategies for habitual alcohol binge drinking are lacking. The development of novel therapeutic and preventative approaches is highly desirable. Accumulating evidence in the past several years has established associations between the gut microbiome and microbial metabolites with drinking behavior, but druggable targets and their underlying mechanism of action are understudied. RESULTS: Here, using a drink-in-the-dark mouse model, we identified a microbiome metabolite-based novel treatment (sodium valerate) that can reduce excessive alcohol drinking. Sodium valerate is a sodium salt of valeric acid short-chain fatty acid with a similar structure as γ-aminobutyric acid (GABA). Ten days of oral sodium valerate supplementation attenuates excessive alcohol drinking by 40%, reduces blood ethanol concentration by 53%, and improves anxiety-like or approach-avoidance behavior in male mice, without affecting overall food and water intake. Mechanistically, sodium valerate supplementation increases GABA levels across stool, blood, and amygdala. It also significantly increases H4 acetylation in the amygdala of mice. Transcriptomics analysis of the amygdala revealed that sodium valerate supplementation led to changes in gene expression associated with functional pathways including potassium voltage-gated channels, inflammation, glutamate degradation, L-DOPA degradation, and psychological behaviors. 16S microbiome profiling showed that sodium valerate supplementation shifts the gut microbiome composition and decreases microbiome-derived neuroactive compounds through GABA degradation in the gut microbiome. CONCLUSION: Our findings suggest that sodium valerate holds promise as an innovative therapeutic avenue for the reduction of habitual binge drinking, potentially through multifaceted mechanisms. Video Abstract.

Baseline gut microbiome and metabolites are correlated with alcohol consumption in a zonisamide clinical trial of heavy drinking alcoholic civilians.

Development and severity of alcohol use disorder (AUD) has been linked to variations in gut microbiota and their associated metabolites in both animal and human studies. However, the involvement of the gut microbiome in alcohol consumption of individuals with AUD undergoing treatment remains unclear. To address this, stool samples (n=48) were collected at screening (baseline) and trial completion from a single site of a multi-site double-blind, placebo-controlled trial of Zonisamide in individuals with AUD. Alcohol consumption, gamma-glutamyl transferase (GGT), and phosphatidylethanol (PEth)levels were measured both at baseline and endpoint of 16-week trial period. Fecal microbiome was analyzed via 16S rRNA sequencing and metabolome via untargeted LC-MS. Both sex (p = 0.003) and psychotropic medication usage (p = 0.025) are associated with baseline microbiome composition. The relative abundance of 12 genera at baseline was correlated with percent drinking reduction, baseline and endpoint alcohol consumption, and changes in GGT and PeTH over the course of treatment (p.adj < 0.05). Overall microbiome community structure at baseline differed between high and low responders (67-100% and 0-33% drinking reduction, respectively; p = 0.03). A positive relationship between baseline fecal GABA levels and percent drinking reduction (R=0.43, p < 0.05) was identified by microbiome function prediction and confirmed by ELISA and metabolomics. Predicted microbiome function and metabolomics analysis have found that tryptophan metabolic pathways are over-represented in low responders. These findings highlight importance of baseline microbiome and metabolites in alcohol consumption in AUD patients undergoing zonisamide treatment.

Randomized Placebo-Controlled Clinical Trial of Dutasteride for Reducing Heavy Drinking in Men.

BACKGROUND: Prior studies indicate that neuroactive steroids mediate some of alcohol's effects. Dutasteride, widely used to treat benign prostatic hypertrophy, is an inhibitor of 5-alpha reductase enzymes, which play a central role in the production of 5α-reduced neuroactive steroids. The purpose of this study was to test dutasteride's tolerability and efficacy for reducing drinking. METHODS: Men (n = 142) with heavy drinking (>24 drinks per week) and a goal to either stop or reduce drinking to nonhazardous levels were randomized to placebo or 1 mg dutasteride daily for 12 weeks. We hypothesized that dutasteride-treated patients would be more successful in reducing drinking. RESULTS: Generalized linear mixed models that included baseline drinking, treatment, time and their 2-way interaction identified significant interactions of treatment-time, such that dutasteride treatment reduced drinking more than placebo. During the last month of treatment, 25% of dutasteride-treated participants had no hazardous drinking (no heavy drinking days and not more than 14 drinks per week) compared with 6% of placebo-treated participants (P = 0.006; NNT = 6). Sensitivity analysis identified baseline drinking to cope as a factor associated with larger reductions in drinking for dutasteride compared with placebo-treated participants. Dutasteride was well tolerated. Adverse events more common in the dutasteride group were stomach discomfort and reduced libido. CONCLUSION: Dutasteride 1 mg daily was efficacious in reducing the number of heavy drinking days and drinks per week in treatment-seeking men. The benefit of dutasteride compared with placebo was greatest for participants with elevated baseline drinking to cope motives.

Short-chain-fatty acid valerate reduces voluntary alcohol intake in male mice.

Background: Despite serious health and social consequences, effective intervention strategies for habitual alcohol binge drinking are lacking. Development of novel therapeutic and preventative approaches is highly desirable. Accumulating evidence in the past several years has established associations between the gut microbiome and microbial metabolites with drinking behavior, but druggable targets and their underlying mechanism of action are understudied. Results: Here, using a drink-in-the-dark mouse model, we identified a microbiome metabolite-based novel treatment (sodium valerate) that can reduce excessive alcohol drinking. Sodium valerate is a sodium salt of valeric acidshort-chain-fatty-acid with similar structure as γ-aminobutyric acid (GABA). Ten days of oral sodium valerate supplementation attenuates excessive alcohol drinking by 40%, reduces blood ethanol concentration by 53%, and improves anxiety-like or approach-avoidance behavior in male mice, without affecting overall food and water intake. Mechanistically, sodium valerate supplementation increases GABA levels across stool, blood, and amygdala. It also significantly increases H4 acetylation in the amygdala of mice. Transcriptomics analysis of the amygdala revealed that sodium valerate supplementation led to changes in gene expression associated with functional pathways including potassium voltage-gated channels, inflammation, glutamate degradation, L-DOPA degradation, and psychological behaviors. 16S microbiome profiling showed that sodium valerate supplementation shifts the gut microbiome composition and decreases microbiome-derived neuroactive compounds through GABA degradation in the gut microbiome. Conclusion: Our findings suggest that the sodium valerate holds promise as an innovative therapeutic avenue for the reduction of habitual binge drinking, potentially through multifaceted mechanisms.

Cumulative stress, PTSD, and emotion dysregulation during pregnancy and epigenetic age acceleration in Hispanic mothers and their newborn infants.

Pregnancy can exacerbate or prompt the onset of stress-related disorders, such as post-traumatic stress disorder (PTSD). PTSD is associated with heightened stress responsivity and emotional dysregulation, as well as increased risk of chronic disorders and mortality. Further, maternal PTSD is associated with gestational epigenetic age acceleration in newborns, implicating the prenatal period as a developmental time period for the transmission of effects across generations. Here, we evaluated the associations between PTSD symptoms, maternal epigenetic age acceleration, and infant gestational epigenetic age acceleration in 89 maternal-neonatal dyads. Trauma-related experiences and PTSD symptoms in mothers were assessed during the third trimester of pregnancy. The MethylationEPIC array was used to generate DNA methylation data from maternal and neonatal saliva samples collected within 24 h of infant birth. Maternal epigenetic age acceleration was calculated using Horvath's multi-tissue clock, PhenoAge and GrimAge. Gestational epigenetic age was estimated using the Haftorn clock. Maternal cumulative past-year stress (GrimAge: p = 3.23e-04, PhenoAge: p = 9.92e-03), PTSD symptoms (GrimAge: p = 0.019), and difficulties in emotion regulation (GrimAge: p = 0.028) were associated with accelerated epigenetic age in mothers. Maternal PTSD symptoms were associated with lower gestational epigenetic age acceleration in neonates (p = 0.032). Overall, our results suggest that maternal cumulative past-year stress exposure and trauma-related symptoms may increase the risk for age-related problems in mothers and developmental problems in their newborns.

Modelling acute glucocorticoid transcriptome response in human embryonic stem cell derived neural cultures.

Our goal is to demonstrate and characterize acute glucocorticoid transcriptome response in human embryonic stem cell (hESC) derived neural cultures. Toward this, we confirmed the differentiation of hESC lines H9 and H1 into post-mitotic neurons and astrocytes, in addition to the expressions of glucocorticoid receptor (GR) protein, and the GR co-chaperone FK506 binding protein 51 (FKBP5). In a series of experiments in hESC-derived neural cultures treated with dexamethasone (Dex) for 6 h, glucocorticoid hormone (GH) response was detected through the transcriptional upregulation of GH-responsive genes, FKBP5 and PER1. Both genes responded to Dex treatment in a dose-dependent fashion, and FKBP5 protein was significantly upregulated after a 12-hour Dex exposure. We additionally examined the transcriptome-wide effects of acute GH exposure in hESC-derived cultures and identified FKBP5 as the most highly up-regulated gene. We identified 30 additional differentially expressed (DE) genes common to cultures derived from both H9 and H1 hESCs whose expression levels changed in both lines with similar magnitudes and direction.

Placental aromatase expression decreased in severe neonatal opioid withdrawal syndrome.

Background: Severe neonatal opioid withdrawal syndrome (NOWS) cannot be predicted. Placental aromatase metabolizes both methadone and buprenorphine and may contribute to the severity of NOWS.Objectives: To determine whether placental aromatase mRNA expression differs in methadone- or buprenorphine-exposed placentas and is associated with NOWS severity.Study design: Prospective multicenter observational cohort study from July 2016 to December 2017. Inclusion: pregnant, ≥18 years old, singleton fetus, nonanomalous, ≥34 weeks at delivery, documented methadone or buprenorphine use. Exclusion: declined sample collection. Severe NOWS is defined as three consecutive Finnegan scores ≥8 or sum of three consecutive scores ≥24 within 72 hours of birth. Finnegan scoring was correlated with placental mRNA expression and compared to umbilical cord drug and metabolite levels. Data were analyzed using descriptive, parametric, and nonparametric statistics and regression analysis. p-Value <.05 was considered significant.Results: Thirty-eight out of 45 (84%) patients were included. Methadone and buprenorphine were used by 29/38 (76%) and 9/38 (24%) of patients, respectively. 19/38 (50%) infants had severe NOWS. Placental aromatase/actin mRNA expression was significantly lower in the placentas of infants with severe NOWS (p = .04). Mean umbilical cord 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP)/methadone ratios were significantly higher in infants with severe NOWS (p = .03). Placental aromatase mRNA expression was weakly to moderately correlated with umbilical cord methadone, buprenorphine, and their metabolite concentrations (r = 0.4-0.8).Conclusion: Placental aromatase mRNA expression was lower and umbilical cord EDDP/methadone ratios were higher in infants with severe NOWS. Additional investigation of placental aromatase in methadone- and buprenorphine-exposed pregnancies is needed.

Induced pluripotent stem cell reprogramming-associated methylation at the GABRA2 promoter and chr4p12 GABAA subunit gene expression in the context of alcohol use disorder.

Twin studies indicate that there is a significant genetic contribution to the risk of developing alcohol use disorder (AUD). With the exception of coding variants in ADH1B and ALDH2, little is known about the molecular effects of AUD-associated loci. We previously reported that the AUD-associated synonymous polymorphism rs279858 within the GABAA α2 receptor subunit gene, GABRA2, was associated with gene expression of the chr4p12 GABAA subunit gene cluster in induced pluripotent stem cell (iPSC)-derived neural cultures. Based on this and other studies that showed changes in GABRA2 DNA methylation associated with schizophrenia and aging, we examined methylation in GABRA2. Specifically, using 69 iPSC lines and neural cultures derived from 47 of them, we examined whether GABRA2 rs279858 genotype predicted methylation levels and whether methylation was related to GABAA receptor subunit gene expression. We found that the GABRA2 CpG island undergoes random stochastic methylation during reprogramming and that methylation is associated with decreased GABRA2 gene expression, an effect that extends to the GABRB1 gene over 600 kb distal to GABRA2. Further, we identified additive effects of GABRA2 CpG methylation and GABRA2 rs279858 genotype on expression of the GABRB1 subunit gene in iPSC-derived neural cultures.

Molecular Correlates of Topiramate and GRIK1 rs2832407 Genotype in Pluripotent Stem Cell-Derived Neural Cultures.

BACKGROUND: There is growing evidence that the anticonvulsant topiramate is efficacious in reducing alcohol consumption. Further, an intronic single nucleotide polymorphism (rs2832407, C A) in the GRIK1 gene, which encodes the GluK1 subunit of the excitatory kainate receptor, predicted topiramate's effectiveness in reducing heavy drinking in a clinical trial. The molecular correlates of GRIK1 genotype that may relate to topiramate's ability to reduce drinking remain unknown. METHODS: We differentiated induced pluripotent stem cells (iPSCs) characterized by GRIK1 rs2832407 genotype from 8 A/A and 8 C/C donors into forebrain-lineage neural cultures. Our differentiation protocol yielded mixed neural cultures enriched for glutamatergic neurons. Basal mRNA expression of the GRIK1 locus was examined via quantitative polymerase chain reaction (qPCR). The effects of acute topiramate exposure on excitatory spontaneous synaptic activity were examined via whole-cell patch-clamp electrophysiology. Results were compared and contrasted between iPSC donor genotypes. RESULTS: Although characterization of the GRIK1 locus revealed no effect of rs2832407 genotype on GRIK1 isoform mRNA expression, a significant difference was observed on GRIK1 antisense-2 expression, which was greater in C/C neural cultures. Differential effects of acute exposure to 5 µM topiramate were observed on spontaneous synaptic activity in A/A versus C/C neurons, with a smaller reduction in excitatory event frequency observed in C/C donor neurons. CONCLUSIONS: This work highlights the use of iPSC technologies to study pharmacogenetic treatment effects in psychiatric disorders and furthers our understanding of the molecular effects of topiramate exposure in human neural cells.

GRM8 genotype is associated with externalizing disorders and greater inter-trial variability in brain activation during a response inhibition task.

OBJECTIVE: The present investigation tested the association of a novel measure of brain activation recorded during a simple motor inhibition task with a GRM8 genetic locus implicated in risk for substance dependence. METHODS: 122 European-American adults were genotyped at rs1361995 and evaluated against DSM-IV criteria for Alcohol Dependence, Cocaine Dependence, Conduct Disorder, and Antisocial Personality Disorder. Also, their brain activity was recorded in response to rare, so-called "No-Go" stimuli presented during a continuous performance test. Brain activity was quantified with two indices: (1) the amplitude of the No-Go P300 electroencephalographic response averaged across trials; and (2) the inter-trial variability of the response. RESULTS: The absence of the minor allele at the candidate locus was associated with all of the evaluated diagnoses. In comparison to minor allele carriers, major allele homozygotes also demonstrated increased inter-trial variability in No-Go P300 response amplitude but no difference in average amplitude. CONCLUSIONS: GRM8 genotype is associated with Alcohol and Cocaine Dependence as well as personality risk factors for dependence. The association may be mediated through an inherited instability in brain function that affects cognitive control. SIGNIFICANCE: The present study focuses on a metric and brain mechanism not typically considered or theorized in studies of patients with substance use disorders.

Adverse childhood experiences, posttraumatic stress, and FKBP5 methylation patterns in postpartum women and their newborn infants.

BACKGROUND: Genetic variation and epigenetic mechanisms involving the stress-related gene FKBP5 have been implicated in the intergenerational transmission of trauma-related effects in adult offspring of trauma-exposed caregivers, but these processes have not been fully explored in postpartum women and their newborn infants. METHODS: Women recruited from a prenatal care clinic during their third trimester of pregnancy (N = 114) completed a battery of instruments assessing adverse childhood experiences (ACEs), adversity in adulthood, posttraumatic stress disorder (PTSD) symptoms, negative emotional state, and emotion dysregulation. FKBP5 rs1360780 genotype and intron 7 methylation were derived from saliva collected from postpartum mothers and their newborn infants within 24 h of delivery. RESULTS: Allele-specific associations of methylation with maternal ACEs and prenatal trauma-related symptoms were evident; however, relations differed between mothers and newborns. In mothers carrying the stress sensitive T-allele (CT and TT genotypes), maternal FKBP5 methylation negatively correlated with threat-based ACEs and maternal PTSD symptoms during pregnancy, but not deprivation-based ACEs. In infants homozygous for the C allele (CC genotype), infant FKBP5 methylation positively correlated with maternal threat-based ACEs and prenatal PTSD symptom severity, but not deprivation-based ACEs or adversity in adulthood. CONCLUSIONS: Our results provide evidence that links maternal threat-based ACEs and trauma-related symptoms during pregnancy with allele-specific epigenetic patterns in postpartum women and their newborn infants. These findings provide mechanistic insight into the potential intergenerational impact of ACEs and the effect of maternal PTSD symptoms during pregnancy.

The moderating effect of FKBP5 and 5-HTTLPR polymorphisms on the day-level association between drinking to cope motivation and negative affect.

Daily levels of drinking to cope (DTC) have been found to be related to negative outcomes such as increased negative affect, and these effects vary across person. We examined whether daily-level effects of DTC motivation were related to two genetic polymorphisms (rs1360780 in the FKBP5 gene and 5-HTTLPR in SLC6A4) thought to be associated with maladaptive drinking and stress-reactivity. We also examined whether these associations changed during the transition from college to post-college life. Participants (N = 839, 55% women) completed an Internet-based 30-day daily diary during college and again five years later in which they reported their previous night's drinking and drinking motivation, and their current day's negative affect. Saliva was collected at wave 1 to provide DNA for genotyping. The within-person association between nighttime DTC motivation and next-day anxiety and depression was stronger (more positive) for FKBP5 rs1360780 T-allele carriers, compared C/C-allele individuals. We also found that 5-HTTLPR L'/S' subjects (but not S'/S' homozygotes), compared to L'/L' homozygotes, showed stronger positive associations between DTC and anxiety. Results for FKBP5 T-allele carriers are discussed in terms of past findings indicating that such individuals tend to demonstrate increased attention toward stressors, thus possibly intensifying the deleterious effects of DTC-motivated drinking.

Entrainment of Circadian Rhythms to Temperature Reveals Amplitude Deficits in Fibroblasts from Patients with Bipolar Disorder and Possible Links to Calcium Channels.

Bipolar disorder (BD) is characterized by recurrent mood episodes, and circadian rhythm disturbances. Past studies have identified calcium channel genes as risk loci for BD. CACNA1C encodes an L-type calcium channel (LTCC) involved in the entrainment of circadian rhythms to light. Another calcium channel, i.e., the ryanodine receptor (RYR), is involved in -circadian phase delays. It is unknown whether variants in CACNA1C or other calcium channels contribute to the circadian phenotype in BD. We hypothesized that, by using temperature cycles, we could model circadian entrainment in fibroblasts from BD patients and controls to interrogate the circadian functions of LTCCs. Using Per2-luc, a bioluminescent reporter, we verified that cells entrain to temperature rhythms in vitro. Under constant temperature conditions, the LTCC antagonist verapamil shortened the circadian period, and the RYR antagonist dantrolene lengthened the period. However, neither drug affected temperature entrainment. Fibroblasts from BD patients and controls also entrained to temperature. In cells from BD patients, the rhythm amplitude was lower under entrained, but not constant, conditions. Temperature entrainment was otherwise similar between BD and control cells. However, the CACNA1C genotype among BD cells predicted the degree to which cells entrained. We conclude that assessment of rhythms under entrained conditions reveals additional rhythm abnormalities in BD that are not observable under constant temperature conditions.

Alcohol-responsive genes identified in human iPSC-derived neural cultures.

Alcohol use contributes to numerous diseases and injuries. The nervous system is affected by alcohol in diverse ways, though the molecular mechanisms of these effects are not clearly understood. Using human-induced pluripotent stem cells (iPSCs), we developed a neural cell culture model to identify the mechanisms of alcohol's effects. iPSCs were generated from fibroblasts and differentiated into forebrain neural cells cultures that were treated with 50 mM alcohol or sham conditions (same media lacking alcohol) for 7 days. We analyzed gene expression using total RNA sequencing (RNA-seq) for 34 samples derived from 10 subjects and for 10 samples from 5 subjects in an independent experiment that had intermittent exposure to the same dose of alcohol. We also analyzed genetic effects on gene expression and conducted a weighted correlation network analysis. We found that differentiated neural cell cultures have the capacity to recapitulate gene regulatory effects previously observed in specific primary neural tissues and identified 226 genes that were differentially expressed (FDR < 0.1) after alcohol treatment. The effects on expression included decreases in INSIG1 and LDLR, two genes involved in cholesterol homeostasis. We also identified a module of 58 co-expressed genes that were uniformly decreased following alcohol exposure. The majority of these effects were supported in independent alcohol exposure experiments. Enrichment analysis linked the alcohol responsive genes to cell cycle, notch signaling, and cholesterol biosynthesis pathways, which are disrupted in several neurological disorders. Our findings suggest that there is convergence between these disorders and the effects of alcohol exposure.

Neuroactive steroid levels and cocaine use chronicity in men and women with cocaine use disorder receiving progesterone or placebo.

BACKGROUND AND OBJECTIVES: Neuroactive steroids (NAS) may play a role in addiction, with observed increases in response to acute stress and drug use, but decreases with chronic substance use, suggesting that NAS neuroadaptations may occur with chronic substance use. However, levels of NAS in addicted individuals have not been systematically examined. Here, we evaluated a panel of NAS in men and women with cocaine use disorder (CUD) who participated in a clinical laboratory study of progesterone. METHODS: Forty six CUD individuals were enrolled in a randomized placebo-controlled laboratory study to evaluate progesterone effects on levels of various NAS. On day 5 of a 7-day inpatient treatment regimen of 400 mg/day progesterone (15M/8F) or placebo (14M/9F), plasma levels of NAS known to be downstream of progesterone (allopregnanolone, pregnanolone), and NAS not in the progesterone synthesis pathway (androstanediol, testosterone, dehydroepiandrosterone [DHEA] and the NAS precursor, pregnenolone) were analyzed using highly sensitive gas chromatography/mass spectrometry (GC/MS). The relationship between each of the NAS and chronicity of cocaine use was also assessed. RESULTS: Progesterone versus placebo significantly increased the GABAergic NAS allopregnanolone and pregnanolone in both CUD men and women. Levels of pregnenolone, testosterone, its GABAergic metabolite androstanediol, and the non-GABAergic DHEA were unaffected by progesterone treatment, and testosterone and androstanediol levels were significantly higher in men than women. Importantly, lower pregnenolone and androstanediol levels were associated with greater years of cocaine use. SCIENTIFIC SIGNIFICANCE: GABAergic NAS that are upstream from the progesterone synthesis pathway appear susceptible to chronic effects of cocaine use. (Am J Addict 2019;28:16-21).

Long-term changes in the effects of episode-specific drinking to cope motivation on daily well-being.

To further understand the role of drinking to cope (DTC) motivation in the development of drinking-related problems during young adulthood, we tested whether the association between episode-specific levels of nighttime DTC motivation and next-day negative affect and self-control depletion symptoms (SCDS) changed from college years to postcollege years (5 years later). We also examined whether these changes were moderated by recent life stress, adult social role attainment and gender, and whether mean levels of these variables were associated with changes in drinking-related problems from college to postcollege years. Participants (N = 927; 54% women) completed a 30-day daily diary during college and again 5 years later in which they reported their previous night's drinking level and motivation and their current negative affect and SCDS. We assessed drinking-related problems at both waves and recent life stress and adult social roles at Wave 2. DTC motivation was positively associated with next-day levels of negative affect and SCDS. The effect of DTC motivation on anxiety and SCDS became stronger over time. The effect of DTC motivation on depressive affect and anger (a) decreased across time among individuals who attained more adult roles and (b) was weaker among individuals who reported lower levels of postcollege life stress. Mean levels of postcollege DTC motivation was indirectly related to changes in drinking-related problems from college to postcollege through mean levels of negative affect and SCDS. Our findings indicate that DTC might exert its unique long-term effects on alcohol use disorders through disruption of daily emotion-regulation processes. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Examining the effects of alcohol on GABAA receptor mRNA expression and function in neural cultures generated from control and alcohol dependent donor induced pluripotent stem cells.

Factors influencing the development of alcohol-use disorder (AUD) are complex and heterogeneous. While animal models have been crucial to identifying actions of alcohol on neural cells, human-derived in vitro systems that reflect an individual's genetic background hold promise in furthering our understanding of the molecular and functional effects of alcohol exposure and the pathophysiology of AUD. In this report, we utilized induced pluripotent stem cell (iPSCs)-derived neural cell cultures obtained from healthy individuals (CTLs) and those with alcohol dependence (ADs) to 1) examine the effect of 21-day alcohol exposure on mRNA expression of three genes encoding GABAA receptor subunits (GABRA1, GABRG2, and GABRD) using quantitative PCR, and 2) examine the effect of acute and chronic alcohol exposure on GABA-evoked currents using whole-cell patch-clamp electrophysiology. iPSCs from CTLs and ADs were differentiated into neural cultures enriched for forebrain-type excitatory glutamate neurons. Following 21-day alcohol exposure, significant treatment effects were observed in GABRA1, GABRG2, and GABRD mRNA expression. A modestly significant interaction between treatment and donor phenotype was observed for GABRD, which was increased in cell cultures derived from ADs. No effect of acute or chronic alcohol was observed on GABA-evoked currents in neurons from either CTLs or ADs. This work extends findings examining the effects of alcohol on the GABAA receptor in human cell in vitro model systems.

Acute Effects of Moderate Alcohol Consumption on Postural Stability in Older Adults.

This study involved healthy community-living older adults in an investigation of the association between moderate alcohol consumption (AC) and acute changes in postural stability and whether the association differed according to pre-AC balance skills. Thirty-nine moderate drinkers aged ≥ 65 years (62% women; mean age: 73.9 ± 6.1 years) consumed a moderate dose of alcohol (0.4 g/kg; administered as two drinks). Breath alcohol concentration and postural stability were measured at five time points (pre-AC and 40, 80, 120, and 160 minutes post-AC) using unipedal stance time (UPST) and center of pressure (CoP) displacement. Pre-AC UPST was used to categorize participants into good-balance (≥30 seconds) and poor-balance (<30 seconds) groups. Peak breath alcohol concentration was 30 mg/dL at 40 minutes post-AC. For all participants, postural stability declined significantly at 80 minutes post-AC (UPST, p = .005; anterior-posterior CoP displacement, p = .029). While the poor-balance group did not show a significant decrease in UPST duration over the course of the study, the good-balance group experienced significant decline at 80 minutes compared with baseline ( p < .001) and remained above the 30-second UPST cutoff. Both groups experienced similar worsening in anterior-posterior CoP displacement at 80 minutes post-AC. Thus, moderate AC was associated with acute decline in postural stability in older adults. The worsened anterior-posterior CoP displacement post-AC in the poor-balance group was of particular concern because these participants were already at lower balance functioning pre-AC. Larger, more representative studies of varying groups of participants are needed to further explore how this change relates to fall incidents and fall risk.

Examining FKBP5 mRNA expression in human iPSC-derived neural cells.

In peripheral blood leukocytes, FKBP5 mRNA expression is upregulated following glucocorticoid receptor activation. The single nucleotide polymorphism rs1360780 in FKBP5 is associated with psychiatric illness and has functional molecular effects. However, examination of FKBP5 regulation has largely been limited to peripheral cells, which may not reflect regulation in neural cells. We used 27 human induced pluripotent stem cell lines (iPSCs) derived from 20 subjects to examine FKBP5 mRNA expression following GR activation. Following differentiation into forebrain-lineage neural cultures, cells were exposed to 1µM dexamethasone and mRNA expression of FKBP5 and NR3C1 analyzed. Results from the iPSC-derived neural cells were compared with those from 15 donor matched fibroblast lines. Following dexamethasone treatment, there was a 670% increase in FKBP5 expression in fibroblasts, mimicking findings in peripheral blood-derived cells, but only a 23% increase in iPSC-derived neural cultures. FKBP5 rs1360780 genotype did not affect the induction of FKBP5 mRNA in either fibroblasts or neural cells. These results suggest that iPSC-derived forebrain-lineage neurons may not be an optimal neural cell type in which to examine relationships between GR activation, FKBP5 expression, and genetic variation in human subjects. Further, FKBP5 induction following GR activation may differ between cell types derived from the same individual.

FKBP5 genotype interacts with early life trauma to predict heavy drinking in college students.

Alcohol use disorder (AUD) is debilitating and costly. Identification and better understanding of risk factors influencing the development of AUD remain a research priority. Although early life exposure to trauma increases the risk of adulthood psychiatric disorders, including AUD, many individuals exposed to early life trauma do not develop psychopathology. Underlying genetic factors may contribute to differential sensitivity to trauma experienced in childhood. The hypothalamic-pituitary-adrenal (HPA) axis is susceptible to long-lasting changes in function following childhood trauma. Functional genetic variation within FKBP5, a gene encoding a modulator of HPA axis function, is associated with the development of psychiatric symptoms in adulthood, particularly among individuals exposed to trauma early in life. In the current study, we examined interactions between self-reported early life trauma, past-year life stress, past-year trauma, and a single nucleotide polymorphism (rs1360780) in FKBP5 on heavy alcohol consumption in a sample of 1,845 college students from two university settings. Although we found no effect of early life trauma on heavy drinking in rs1360780*T-allele carriers, rs1360780*C homozygotes exposed to early life trauma had a lower probability of heavy drinking compared to rs1360780*C homozygotes not exposed to early life trauma (P < 0.01). The absence of an interaction between either current life stress or past-year trauma, and FKBP5 genotype on heavy drinking suggests that there exists a developmental period of susceptibility to stress that is moderated by FKBP5 genotype. These findings implicate interactive effects of early life trauma and FKBP5 genetic variation on heavy drinking. © 2016 Wiley Periodicals, Inc.