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.

Circadian clock period inversely correlates with illness severity in cells from patients with alcohol use disorders.

BACKGROUND: Clinical and genetic studies suggest circadian clock genes may contribute to biological mechanisms underlying alcohol use disorders (AUD). In particular, the Per2 gene regulates alcohol consumption in mutant animals, and in humans with AUD, the 10870 variant in PER2 has been associated with alcohol consumption. However, with respect to function, the molecular clock remains largely uncharacterized in AUD patients. METHODS: In skin fibroblast cultures from well-characterized human AUD patients (n = 19) and controls (n = 13), we used a bioluminescent reporter gene (Per2::luc) to measure circadian rhythms in gene expression at high sampling density for 5 days. Cells were genotyped for the PER2 10870 variant. The rhythm parameters period and amplitude were then analyzed using a case-control design and by genetic and clinical characteristics of the AUD subjects. RESULTS: There were no differences between AUD cases and controls in rhythm parameters. However, period was inversely correlated with illness severity (defined as the number of alcohol dependence criteria met). The PER2 variant 10870 was not associated with differences in rhythm parameters. CONCLUSIONS: Our data suggest that differences in the cellular circadian clock are not pronounced in fibroblasts from AUD cases and controls. However, we found evidence that the circadian clock may be associated with an altered trajectory of AUD, possibly related to illness severity. Future work will be required to determine the mechanistic basis of this association.

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.

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.

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.

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.