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Sens, J. P.

Publications and source records attributed to Sens, J. P..

5 recordsLinked to original sources

Granulocyte colony-stimulating factor acts through calcium-permeable AMPA receptors to potentiate cocaine reward

Neuroimmune interactions have emerged as critical modulators of substance use disorders and may represent promising translational therapeutic targets. In prior work, we demonstrated that the cytokine granulocyte colony stimulating factor (G-CSF) is elevated in mice following cocaine exposure, with circulating levels correlating with cocaine intake and locomotor sensitization. Additionally, exogenous G-CSF enhances cocaine reward and increases low-dose cocaine self-administration. We have further shown that repeated G-CSF administration alters expression of glutamatergic synapse-associated proteins following cocaine-seeking behavior. Building on these findings, the present studies examined the molecular consequences of repeated administration of G-CSF, cocaine, or their combination, with a focus on glutamatergic signaling pathways. We also tested whether altered glutamate receptor expression contributes to G-CSF-mediated enhancement of cocaine reward. Repeated combined administration of G-CSF and cocaine produced robust changes in glutamate-associated and synapse-related protein expression within the nucleus accumbens and medial prefrontal cortex. These molecular adaptations were accompanied by increased synaptic density in the nucleus accumbens. Finally, pharmacological inhibition of calcium-permeable AMPA receptors within the nucleus accumbens reversed the G-CSF-induced enhancement of cocaine conditioned place preference. Together, these findings indicate that G-CSF enhances cocaine reward at least in part by promoting glutamatergic synaptic remodeling in the nucleus accumbens, identifying a neuroimmune-glutamate mechanism that may be leveraged for therapeutic intervention.

neuroscience↗

Brief disruption of the microbiome has age-dependent effects on morphine reward and gene expression in the medial prefrontal cortex of adolescent and adult mice

Adolescence is a critical period for the initiation of problematic drug use, which significantly increases the risk of developing substance use disorders later in life. This heightened vulnerability is partly attributed to the immaturity of the prefrontal cortex, a brain region both essential for decision-making and implicated in drug reward. During adolescence, peripheral systems, such as the gut microbiome, also undergo substantial changes. Emerging evidence suggests that disruptions to the gut microbiome can influence gene expression and drug reward behaviors in rodent models. In this study, we investigated the effects of microbiome disruption on morphine reward and prefrontal cortical gene expression in adolescent and adult mice. Using oral antibiotics to transiently disrupt the microbiome, we found that short-term antibiotic exposure reduced morphine place preference specifically in adolescent mice. In a separate cohort, we observed that antibiotic treatment altered the transcriptomic response to morphine in the medial prefrontal cortex across all age groups. Notably, the transcriptomic changes induced by antibiotics and morphine were age-specific, with distinct gene expression patterns observed in adolescents compared to adults. These findings establish a foundation for future research into the role of the gut microbiome in opioid reward and highlight potential gene pathways underlying age-dependent differences in opioid sensitivity.

neuroscience↗

Synaptogyrin-3 Prevents Cocaine Addiction and Dopamine Deficits

Synaptogyrin-3, a functionally obscure synaptic vesicle protein, interacts with vesicular monoamine and dopamine transporters, bringing together dopamine release and reuptake sites. Synaptogyrin-3 was reduced by chronic cocaine exposure in both humans and rats, and synaptogyrin-3 levels inversely correlated with motivation to take cocaine in rats. Synaptogyrin-3 overexpression in dopamine neurons reduced cocaine self-administration, decreased anxiety-like behavior, and enhanced cognitive flexibility. Overexpression also enhanced nucleus accumbens dopamine signaling and prevented cocaine-induced deficits, suggesting a putative therapeutic role for synaptogyrin-3 in cocaine use disorder.

neuroscience↗

Synchrony between midbrain gene transcription and dopamine terminal regulation is modulated by chronic alcohol drinking

Alcohol use disorder is marked by disrupted behavioral and emotional states which persist into abstinence. The enduring synaptic alterations that remain despite the absence of alcohol are of interest for interventions to prevent relapse. Here, 28 male rhesus macaques underwent over 20 months of alcohol drinking interspersed with three 30-day forced abstinence periods. After the last abstinence period, we paired direct sub-second dopamine monitoring via ex vivo voltammetry in nucleus accumbens slices with RNA-sequencing of the ventral tegmental area. We found persistent augmentation of dopamine transporter function, kappa opioid receptor sensitivity, and dynorphin release - all inhibitory regulators which act to decrease extracellular dopamine. Surprisingly, though transcript expression was not altered, the relationship between gene expression and functional readouts of these encoded proteins was highly dynamic and altered by drinking history. These results outline the long-lasting synaptic impact of alcohol use and suggest that assessment of transcript-function relationships is critical for the rational design of precision therapeutics.

neuroscience↗

Systematic analysis of dark and camouflaged genes: disease-relevant genes hiding in plain sight

BackgroundThe human genome contains dark gene regions that cannot be adequately assembled or aligned using standard short-read sequencing technologies, preventing researchers from identifying mutations within these gene regions that may be relevant to human disease. Here, we identify regions that are dark by depth (few mappable reads) and others that are camouflaged (ambiguous alignment), and we assess how well long-read technologies resolve these regions. We further present an algorithm to resolve most camouflaged regions (including in short-read data) and apply it to the Alzheimers Disease Sequencing Project (ADSP; 13142 samples), as a proof of principle.\n\nResultsBased on standard whole-genome lllumina sequencing data, we identified 37873 dark regions in 5857 gene bodies (3635 protein-coding) from pathways important to human health, development, and reproduction. Of the 5857 gene bodies, 494 (8.4%) were 100% dark (142 protein-coding) and 2046 (34.9%) were [≥]5% dark (628 protein-coding). Exactly 2757 dark regions were in protein-coding exons (CDS) across 744 genes. Long-read sequencing technologies from 10x Genomics, PacBio, and Oxford Nanopore Technologies reduced dark CDS regions to approximately 45.1%, 33.3%, and 18.2% respectively. Applying our algorithm to the ADSP, we rescued 4622 exonic variants from 501 camouflaged genes, including a rare, ten-nucleotide frameshift deletion in CR1, a top Alzheimers disease gene, found in only five ADSP cases and zero controls.\n\nConclusionsWhile we could not formally assess the CR1 frameshift mutation in Alzheimers disease (insufficient sample-size), we believe it merits investigating in a larger cohort. There remain thousands of potentially important genomic regions overlooked by short-read sequencing that are largely resolved by long-read technologies.

genomics↗