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Datta, U.

Publications and source records attributed to Datta, U..

4 recordsLinked to original sources

A shared genetic regulator of metabolism and addiction-related behavior in mice and humans

Substance use disorders and other mental health conditions often co-occur with metabolic disorders, suggesting shared biological underpinnings1. These heightened behavioral and physiological responses may have evolved to promote survival during resource scarcity but can become maladaptive in modern environments2. The genetic mechanisms linking these traits have remained elusive. Here, we show that a variable gene enhancer in mice jointly regulates genes encoding an epigenetic factor (Eed) and a mitochondrial enzyme (Me3) thereby influencing propensity to addiction-related behaviors and mitochondrial function. We further identify variation in a corresponding enhancer in humans regulating EED and ME3 associated with substance use, psychiatric and metabolic disorders. These findings reveal a convergent genetic regulatory network linking mitochondrial biology to behavioral and metabolic risk, offering insight into how genetic variation in beneficial regulatory pathways can predispose individuals to substance use disorders and related conditions.

genetics↗

Behavioral variation across multiple phases of intravenous cocaine self-administration among genetically diverse mouse populations

Genetic and other predisposing factors can influence the progression from initiation of drug intake to compulsive substance use through distinct biobehavioral processes. Operant cocaine self-administration studies in laboratory mice offer a powerful method to dissect the biology of this progression from initiation, dose-response, extinction, and cued reinstatement in a controlled, tractable system. However, many such studies encompass limited genetic diversity and rarely examine self-administration behaviors beyond the acquisition stage. Here, we study three high-diversity mouse populations - 50 strains from the Collaborative Cross (CC) reference panel, a large sample of Diversity Outbred (J:DO) population and their eight founder strains - to characterize the varied phenotypic manifestation of behaviors across multiple phases of cocaine intravenous self-administration (IVSA) in both sexes. We observed distinct strain differences among the founders and CC strains in all phases of self-administration, with heritability estimates ranging from 0 to 0.585 and many CC and J:DO phenotypic values exceeding the range of founders including the C57BL/6J strain. Sex differences were common across behaviors, some manifesting as main effects, others as strain interactions. Finally, by adopting a multi-stage design, we identified extreme strains for various cocaine intake and response traits and evaluated whether these strains exhibited differences in behavioral assays that model compulsive drug seeking. Together, these findings demonstrate the utility of extended self-administration protocols in advanced mouse populations for discovery and characterization of biological mechanisms of substance use traits and for preclinical studies in relevant, complex mouse models.

genetics↗

Male and Female Mice Are Similarly Susceptible to Chronic Nondiscriminatory Social Defeat Stress Despite Differences in Attack Frequency from Aggressor

RationaleMood disorders are often precipitated by chronic stress and can result in an inability to adapt to the environment and increased vulnerability to challenging experiences. While diagnoses of mood disorders are diagnosed twice as frequently in women than in men, most preclinical chronic social defeat stress mouse models exclude females due to decreased aggression toward female intruders. ObjectivesWe previously reported that the chronic non-discriminatory social defeat stress (CNSDS) paradigm is effective in both sexes, allowing for comparisons between male and female mice. We aimed to improve the screening protocol to identify CD-1 aggressors for use in CNSDS and the method for determining susceptibility to CNSDS. Finally, we aimed to determine whether susceptibility to CNSDS correlated with impaired performance in a satiety- based outcome devaluation task. MethodsWe analyzed CNSDS screening and social defeat sessions to determine appropriate parameters for selecting CD-1 aggressors and investigated aggressions toward male and female intruder mice. We also investigated CNSDS effects on a reward valuation task. ResultsWe observed that despite receiving fewer attacks, female mice are equally susceptible to CNSDS as males and that CNSDS abolished satiety-based outcome devaluation in susceptible male and female mice, but not in resilient male and female mice. ConclusionsThese data suggest that CNSDS-defined susceptible and resilient phenotypes extend to reward behaviors.

neuroscience↗

Genetic variation and sex differences are missed opportunities for addiction biology.

Concerns about external validity of rodent models and translation of findings across species are often based on narrow investigations of populations with limited diversity. Sources of individual variation - including genetics and sex - are only infrequently encompassed in model organism studies. As with most complex diseases, risk for cocaine use disorder is subject to considerable inter-individual variation. Explicit inclusion of individual differences in rodent research may reveal conserved phenotypes and molecular systems relevant to human addiction. We surveyed cocaine-related traits in both males and females of eight inbred mouse strains whose genomes collectively capture 90% of the genetic diversity of the mouse species. Across these strains, individual differences explained a substantial proportion of variance in cocaine-responsive or cocaine response-predictive behavioral and physiological phenotypes. Wild-derived mouse strains often extended the phenotypic ranges of these behaviors beyond what is observed in conventional laboratory strains. Striatum transcriptional responses to cocaine were also highly dependent upon strain and sex differences; most cocaine-responsive genes were differentially expressed in a manner moderated by strain, sex, or their combination. We compared the strain- and sex-mediated transcriptional responses to cocaine in mice to transcriptomic analysis of people with cocaine use disorder and found that mouse similarity to humans was highly dependent upon mouse genetic background and sex. Specifically, male WSB/EiJ mice and female NOD/ShiLtJ mice exhibited the greatest degree of neural transcriptional consilience with humans with cocaine use disorder. Model organism diversity thus represents a crucial source of biological information that can substantially improve external validity of neuropsychiatric research. Significance StatementLaboratory mice are widely used in research on neurobiological mechanisms of addiction, but most studies use a single strain and often sex of mice. To assess how individual differences in mice modulate addiction-related traits and how this impacts comparative analysis with humans, we studied cocaine-relevant behaviors and brain molecular correlates in both males and females of genetically diverse mouse strains. In this population, individual differences related to sex and/or genetics explain large proportions of differences in cocaine-related traits. Importantly, brain gene expression data demonstrated that some strains mimic human genomic states more readily than others. Individual differences thus represent a crucial and underdeveloped source of biological information about addiction mechanisms that may influence the translational utility of such studies.

neuroscience↗