Biology subjects

Phillips, T. J.

Publications and source records attributed to Phillips, T. J..

3 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↗

bioRxiv2019

Maternal antioxidant treatment prevents behavioural and neural changes in offspring exposed to prenatal social stress

Maternal exposure to social stress during pregnancy is associated with an increased risk of psychiatric disorders in the offspring in later life. However, the mechanism through which the effects of maternal stress are transmitted to the foetus is unclear. Using a rat model, we explored the mechanisms by which maternal social stress is conveyed to the foetus and the potential for targeted treatment to prevent disease in the offspring. Maternal stress increased circulating corticosterone in the mother, but not the foetuses. Maternal stress also induced oxidative stress in the placenta, but not in the foetal brain, and this was prevented by administration of a nanoparticle-bound antioxidant. Moreover, antioxidant treatment prevented prenatal stress-induced anxiety-like behaviour in the adult male offspring, along with several stress-induced neuroanatomical, neurochemical and gene expression changes in the offspring brain. Importantly, many of these neural effects were mimicked in neuronal cultures by application of placental-conditioned medium or foetal plasma from stressed pregnancies. Both placental-conditioned medium and foetal plasma contained differentially abundant extracellular microRNAs following prenatal stress. The present study highlights the crucial role of the placenta, and the molecules it secretes, in foetal brain development and provides evidence of the potential for treatment that can prevent maternal stress-induced foetal programming of neurological disease.

neuroscience↗