Biology subjects

Ozburn, A. R.

Publications and source records attributed to Ozburn, A. R..

4 recordsLinked to original sources

bioRxiv2025

Chronic Ethanol Drinking Alters Medial Prefrontal Cortex and Nucleus Accumbens Astrocyte Translatome and Extracellular Matrix Glycosaminoglycans

Alcohol Use Disorder is a leading preventable cause of morbidity and mortality, yet knowledge of mechanisms driving ethanol-related neuroplasticity remains incomplete. While research has traditionally focused on neuronal signaling, emerging evidence implicates astrocytes in addiction-related adaptations. Here, we investigated the astrocyte-specific molecular consequences of chronic ethanol consumption in the prefrontal cortex and nucleus accumbens, two brain regions critical for executive control and reward processing. Using Translating Ribosome Affinity Purification RNA-seq and bulk RNA-seq in Aldh1l1-EGFP/Rpl10a mice, expressing an EGFP tag on astrocyte ribosomes, we identified hundreds of differentially translated astrocytic genes following chronic continuous two-bottle choice ethanol drinking. Sex-specific analyses revealed greater astrocytic changes in the female PFC and male NAc. Pathway enrichment highlighted extracellular matrix remodeling, synaptic signaling, mitochondrial function, and immune-related pathways. Analyses of individual drinking levels further demonstrated distinct correlations between ethanol intake and astrocytic translation. The major components of the brain extracellular matrix are chondroitin sulfate proteoglycans, produced primarily by astrocytes and covalently bound to chondroitin sulfate glycosaminoglycan chains. Complementary mass spectrometry/liquid chromatography analyses of chondroitin sulfate, heparan sulfate, and hyaluronic acid glycosaminoglycan disaccharides revealed ethanol-induced alterations in chondroitin sulfate glycosaminoglycan sulfation patterns, with additional baseline differences identified between selectively bred high- and low-ethanol preference lines. Together, these findings indicate that astrocytes undergo profound sex- and region-specific adaptations to chronic ethanol, implicating extracellular matrix and glycosaminoglycan remodeling as key risk-factors for and mediators of chronic ethanol-related neuroplasticity.

neuroscience↗

bioRxiv2025

Genomic and Behavioral Signatures of Selection for Ethanol Preference from the Heterogeneous Stock Collaborative Cross Mice: The Central Nucleus of the Amygdala

Alcohol use disorder (AUD) is a complex disease with heritability of [~]0.5, indicating genetic and non-genetic factors contribute to risk. Identifying gene expression networks contributing to risk using post-mortem human brain tissue has the limitation of conflating risk for AUD with consequences of alcohol use. We leveraged mice selectively bred for differential ethanol preference from a highly genetically diverse population to overcome this limitation. Ethanol intake was highly correlated with preference, high-preferring (HP) mice consumed more sweet-but not bitter-tasting solutions compared to low-preferring (LP) mice, and the lines did not differ in rate of ethanol elimination. Adult, ethanol-naive HP and LP mice contributed tissue from the central nucleus of the amygdala (CeA), a region critical to ethanol preference and intake. Single-nuclei and bulk RNA sequencing data were used to identify cell types and transcriptome changes related to selective breeding for differential risk for ethanol preference. Single nuclei analysis identified populations of inhibitory ([~]48% of cells) and excitatory ([~]23%) neurons, and non-neuronal ([~]29%) cells, but no differences in cell-type composition or gene expression were identified between the lines. Bulk CeA analysis identified differences between the lines for: (1) gene expression (2996 genes), (2) expression variability (426 genes), and (3) wiring (407 significant gene-gene correlations). Overall, lower variance was found in the HP line. Reduced gene-gene correlation, also found in HP mice, suggested that selection for high preference induced changes in transcriptional regulation resulting in reduced connectivity, specific to gene networks enriched in markers for inhibitory neurons expressing Isl1 and Tac1.

genomics↗

bioRxiv2024

Sex differences in nucleus accumbens core circuitry engaged by binge-like ethanol drinking

Growing parity in Alcohol Use Disorder (AUD) diagnoses in men and women necessitates consideration of sex as a biological variable. In humans and rodents, the nucleus accumbens core (NAcc) regulates alcohol binge drinking, a risk factor for developing AUD. We labeled NAcc inputs with a viral retrograde tracer and quantified whole-brain c-Fos to determine the regions and NAcc inputs differentially engaged in male and female mice during binge-like ethanol drinking. We found that binge-like ethanol drinking females had 129 brain areas with greater c-Fos than males. Moreover, ethanol engaged more NAcc inputs in binge-like ethanol drinking females (as compared with males), including GABAergic and glutamatergic inputs. Relative to water controls, ethanol increased network modularity and decreased connectivity in both sexes and did so more dramatically in males. These results demonstrate that early-stage binge-like ethanol drinking engages brain regions and NAcc-inputs and alters network dynamics in a sex-specific manner. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=86 SRC="FIGDIR/small/608144v1_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@c47435org.highwire.dtl.DTLVardef@1a97d69org.highwire.dtl.DTLVardef@68b2cborg.highwire.dtl.DTLVardef@1b2453a_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical Summary:C_FLOATNO Binge-like ethanol drinking engages more regions and NAcc inputs in female relative to male mice.Left: Comparison of regions with both greater c-Fos expression and c-Fos+GFP colocalization in female relative to male ethanol drinking mice. Right: NAcc inputs engaged by binge-like ethanol drinking compared to water drinking mice, sex collapsed. Thalamic (TH) regions include left parasubthalamic nucleus, left anteromedial nucleus of the thalamus, left central medial nucleus of the thalamus, left medial group of the dorsal thalamus, left subparafascicular nucleus, left peripeduncular nucleus, and right paraventricular nucleus of the thalamus. EW, Edinger-Westphal nucleus; GU, gustatory areas. Bottom Middle: NAcc inputs with greater engagement in male than female ethanol drinking mice (left and right main olfactory bulbs (MOB). Bottom Right: NAcc inputs with greater engagement in female than male ethanol drinking mice. Amygdala (AMY) regions include left anterior amygdalar area and left intercalated amygdalar area. Hippocampal (HPF) regions include right dentate gyrus, right Field CA1, right Field CA2, and right Field CA3. Hypothalamic (HY) regions include left and right lateral hypothalamic area, left and right periventricular hypothalamic nucleus, preoptic part, right dorsomedial nucleus of the hypothalamus, right posterior hypothalamic nucleus, and right ventromedial hypothalamic nucleus. Midbrain (MB) regions include left and right midbrain reticular nucleus, retrorubral area, left and right superior colliculus, motor related, left nucleus of the brachium of the inferior colliculus, left nucleus of the posterior commissure, left olivary pretectal nucleus, left posterior pretectal nucleus, left superior colliculus, sensory related, and right substantia nigra, reticular parts. Pontine (P) regions include left superior central nucleus raphe, left supratrigeminal nucleus, right nucleus raphe pontis, right pontine reticular nucleus, and right superior olivary complex. Thalamic (TH) regions include left and right lateral dorsal nucleus of the thalamus, right dorsal part of the lateral geniculate complex, right lateral posterior nucleus of the thalamus, and right parasubthalamic nucleus. CB, Cerebellum; MA, magnocellular nucleus; SSp-m, primary somatosensory cortex, mouth; Created with BioRender.com. See Table S18 for additional information. C_FIG

neuroscience↗

bioRxiv2021

The FDA-approved drug apremilast suppresses alcohol intake: clinical and pre-clinical validation

Treatment options for Alcohol Use Disorders (AUD) have minimally advanced since 2004, while the annual deaths and economic toll have become alarmingly high. Bringing potential therapeutics beyond the bench and into the clinic for AUD requires rigorous pharmacological screening across molecular, behavioral, pre-clinical, and clinical studies in neuroscience. The repurposing of FDA-approved compounds is an effective and expedited means of screening pharmacotherapies for AUD. Here, we demonstrate that apremilast, a phosphodiesterase type 4 inhibitor that is FDA approved for psoriasis and psoriatic arthritis, reduces binge-like alcohol intake and behavioral measures of motivation in unique, preclinical genetic risk models for drinking to intoxication and reduces excessive alcohol drinking in models of stress-facilitated drinking and alcohol dependence. In a double blind, placebo-controlled human laboratory study in non-treatment seeking individuals with AUD, apremilast significantly reduced the number of drinks per day. Lastly, using site-directed drug infusions and electrophysiology we determined that apremilast may act by increasing neural activity in the nucleus accumbens, an important alcohol-related brain region, to reduce alcohol intake in mice. These results demonstrate that apremilast reduces excessive alcohol drinking across a spectrum of AUD severity and support its importance as a potential therapeutic for AUD.

animal behavior and cognition↗