Single Nucleus Transcriptomes from the Ventral Midbrain of Opioid Overdose Cases and Controls
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE240457 | GEO | 2023/08/18
REPOSITORIES: GEO
Similar Datasets
Project description:In addition to their intrinsic rewarding properties. opioids can also evoke aversive reactions that protect against misuse. Cellular mechanisms that govern the interplay between opioid reward and aversion are poorly understood. We used whole-brain activity mapping to show that neurons in the dorsal peduncular nucleus (DPn) are highly responsive to the opioid oxycodone. Connectomic profiling revealed that DPn neurons innervate the parabrachial nucleus (PBn). Spatial and single-nuclei transcriptomics resolved a unique population of PBn-projecting pyramidal neurons restricted to the DPn that express μ-opioid receptors (μORs). Disrupting μOR signaling in these neurons switched oxycodone from rewarding to aversive and exacerbated the severity of opioid withdrawal. These findings identify DPn neurons as key substrates for the abuse liability of opioids.
2024-06-07 | GSE260687 | GEO
Project description:The United States is currently facing a severe opioid epidemic, therefore addressing how opioids induce rewarding behaviors could be key to a solution for this medical and societal crisis. Recently, the endogenous cannabinoid system has emerged as a hot topic in the study of opioid reward but relatively little is known about how chronic opioid exposure may affect this system. In the present study, we investigated how chronic morphine may modulate the endogenous cannabinoid system in the ventral tegmental area (VTA), a critical region in the mesolimbic reward circuitry. Our studies found that the VTA expresses 32 different proteins or genes related to the endogenous cannabinoid system; 3 of these proteins or genes were significantly affected after chronic morphine exposure. We also investigated the effects of acute and chronic morphine treatment on the production of the primary endocannabinoids, 2-Arachidonoylglycerol (2-AG) and anandamide (AEA), and identified that acute, but not chronic, morphine treatment significantly reduced AEA production in the VTA; 2-AG levels were unchanged in either condition. Lastly, our studies exhibited a systemic enhancement of 2-AG tone via inhibition of monoacylglycerol lipase (MAGL)-mediated degradation and the pharmacological activation of cannabinoid receptor 2 (CB2R) significantly suppressed chronic morphine-induced conditioned place preference. Taken together, our studies offer a broad picture of chronic morphine-induced alterations of the VTA endogenous cannabinoid system, provide several uncharacterized targets that could be used to develop novel therapies, and identify how manipulation of the endocannabinoid system can mitigate opioid reward to directly address the ongoing opioid epidemic.
2021-04-08 | PXD023096 | Pride
Project description:The development of physical dependence and addiction disorders due to misuse of opioid analgesics is a major concern with pain therapeutics. In this study, we developed a mouse model of oxycodone exposure to gain insight into genes and molecular pathways in reward-related brain regions that are affected by prolonged exposure to oxycodone and subsequent withdrawal in the presence or absence of chronic neuropathic pain. RNA-Sequencing (RNA-Seq) and bioinformatic analyses revealed that oxycodone withdrawal alone triggers robust gene expression adaptations in the nucleus accumbens (NAc), medial prefrontal cortex (mPFC), and ventral tegmental area (VTA), with numerous genes and pathways selectively affected by oxycodone withdrawal under peripheral nerve injury states. Our pathway analysis predicted that histone deacetylase 1 (HDAC1), an epigenetic modifier with a prominent role in striatal plasticity, is a top upstream regulator in opioid withdrawal in both the NAc and mPFC. Indeed, treatment with the novel HDAC1/2 inhibitor RBC1HI (Regenacy Brain Class 1 HDAC Inhibitor) attenuated behavioral manifestations of oxycodone withdrawal, with the drug being more efficacious under states of neuropathic pain. Since RBC1HI displays antiallodynic actions in models of neuropathic pain, inhibition of HDAC1/2 may provide an avenue for chronic pain patients dependent on opioids to transition to non-opioid analgesics. Overall, our study highlights transcriptomic events in components of the reward circuitry associated with oxycodone withdrawal under pain-free and prolonged neuropathic pain states, thereby providing information on possible new targets for the treatment of physical dependence to opioids and transitioning individuals to non-opioid medications for chronic pain management.
2023-01-23 | GSE223541 | GEO
Project description:The opioid receptors are important regulators of pain, reward, and addiction. Limited evidence suggests the mu and delta opioid receptors form a heterodimer (MDOR), which may act as a negative feedback brake on opioid-induced analgesia. However, evidence for the MDOR in vivo is indirect and limited, and there are few selective tools available. We recently published the first MDOR-selective antagonist, D24M, allowing us to test the role of the MDOR in mice. We thus co-treated CD-1 mice with D24M and opioids in tail flick, paw incision, and chemotherapy-induced peripheral neuropathy pain models. D24M treatment enhanced oxymorphone anti-nociception in all models by 52.3%-628%. This enhancement could not be replicated with the mu and delta selective antagonists CTAP and naltrindole, and D24M had a mild transient effect in the Rotarod test, suggesting this increase is selective to the MDOR. However, D24M had no effect on morphine or buprenorphine, suggesting that only specific opioids interact with the MDOR. To find a mechanism we performed phosphoproteomic analysis on brainstems of mice. We found that the kinases Src and CaMKII were repressed by oxymorphone, which was restored by D24M. We were able to confirm the role of Src and CaMKII in D24M-enhanced anti-nociception using small molecule inhibitors (KN93, Src-I1). Together these results provide direct in vivo evidence that the MDOR acts as an opioid negative feedback brake, which occurs via the repression of Src and CaMKII signal transduction. These results further suggest that MDOR antagonism could be a means to improve clinical opioid therapy.
2023-03-10 | PXD022106 | Pride
Project description:Opioid analgesics are frequently prescribed in the United States and worldwide. However, serious side effects such as addiction, immunosuppression and gastrointestinal symptoms limit long term use. In the current study using a chronic morphine-murine model a longitudinal approach was undertaken to investigate the role of morphine modulation of gut microbiome as a mechanism contributing to the negative consequences associated with opioids use. The results revealed a significant shift in the gut microbiome and metabolome within 24 hours following morphine treatment when compared to placebo. Morphine induced gut microbial dysbiosis exhibited distinct characteristic signatures profiles including significant increase in communities associated with pathogenic function, decrease in communities associated with stress tolerance. Collectively, these results reveal opioids-induced distinct alteration of gut microbiome, may contribute to opioids-induced pathogenesis. Therapeutics directed at these targets may prolong the efficacy long term opioid use with fewer side effects.
2018-04-16 | E-MTAB-5550 | biostudies-arrayexpress
Project description:Opioids are powerful analgesics but carry many contingencies that can lead to opioid-use disorder. Significant energy has been invested in understanding the molecular actions of the opioid alkaloids, particularly their relationship with the opioid receptors at the cell surface. However, there is growing awareness of the opioid-receptor-independent and intracellular actions of opioids that may contribute to their overall pharmacology. The investigation of these interactions is stymied by a lack of relevant opioid chemical tools to probe intracellular actions of the opioids. To investigate the intracellular interactions of the opioids, we designed and developed two opioid probes: photo-click morphine (PCM-2) as a photo-affinity probe for morphine and dialkynyl-acetyl morphine (DAAM) as a metabolic acetate reporter for heroin. Application of these probes to SH-SY5Y, HEK293T, and U2OS cells revealed that PCM-2 and DAAM primarily localize to the lysosome by confocal microscopy and chemical proteomics studies. Interaction site identification by mass spectrometry revealed the mitochondria phosphate carrier protein, solute carrier family 25 member 3, SLC25A3, and histone H2B as acetylation targets of DAAM. This study provides the first chemical probes for the study of the intracellular targets of opioid alkaloids.
2024-05-07 | PXD045676 | Pride
Project description:Overdose of acetaminophen (APAP) is the major cause of acute liver failure in the Western world with very limited treatment options. Previous studies from our groups and others have shown that timely activation of liver regeneration is a critical determinant of transplant-free survival of APAP-induced acute liver failure (ALF) patients. We used affy microarrays to explore the mechanisms of transcriptional expression in YAP-KO mice after 300mg/kg APAP overdose.
2021-10-04 | GSE183119 | GEO
Project description:Opioids analgesics are frequently prescribed in the United States and worldwide. However, serious side effects such as addiction, immunosuppression and gastrointestinal symptoms limit their use. It has been recently demonstrated that morphine treatment results in significant disruption in gut barrier function leading to increased translocation of gut commensal bacteria. Further study indicated distinct alterations in the gut microbiome and metabolome following morphine treatment, contributing to the negative consequences associated with opioid use. However, it is unclear how opioids modulate gut homeostasis in the context of a hospital acquired bacterial infection. In the current study, a mouse model of C. rodentium infection was used to investigate the role of morphine in the modulation of gut homeostasis in the context of a hospital acquired bacterial infection. Citrobacter rodentium is a natural mouse pathogen that models intestinal infection by enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli (EHEC) and causes attaching and effacing lesions and colonic hyperplasia. Morphine treatment resulted in 1) the promotion of C. rodentium systemic dissemination, 2) increase in virulence factors expression with C. rodentium colonization in intestinal contents, 3) altered gut microbiome, 4) damaged integrity of gut epithelial barrier function, 5) inhibition of C. rodentium-induced increase in goblet cells, and 6) dysregulated IL-17A immune response. This is the first study to demonstrate that morphine promotes pathogen dissemination in the context of intestinal C. rodentium infection, indicating morphine modulates virulence factor-mediated adhesion of pathogenic bacteria and induces disruption of mucosal host defense during C. rodentium intestinal infection in mice. This study demonstrates and further validates a positive correlation between opioid drug use/abuse and increased risk of infections, suggesting over-prescription of opioids may increase the risk in the emergence of pathogenic strains and should be used cautiously. Therapeutics directed at maintaining gut homeostasis during opioid use may reduce the comorbidities associated with opioid use for pain management.
2020-02-18 | E-MTAB-7503 | biostudies-arrayexpress
Project description:The striatum in the brain is involved in various behavioral functions, including reward, and disease processes, such as opioid use disorder (OUD). Further understanding of the role of striatal subregions in reward behaviors and their potential associations with OUD requires molecular identification of specific striatal cell types in human brain. The human striatum contains subregions based on different anatomical, functional, and physiological properties, with the dorsal striatum further divided into caudate and putamen. Both caudate and putamen are associated with alterations in reward processing, formation of habits, and development of negative affect states in OUD. Using single nuclei RNA-sequencing of human postmortem caudate and putamen, we identified canonical neuronal cell types in striatum (e.g., dopamine receptor 1 or 2 expressing neurons, D1 or D2) and less abundant subpopulations, including D1/D2 hybrid neurons and multiple classes of interneurons. By comparing unaffected subjects to subjects with OUD, we found neuronal-specific differences in pathways related to neurodegeneration, interferon response, and DNA damage. DNA damage markers were also elevated in striatal neurons of rhesus macaques following chronic opioid administration. We identified sex-dependent differences in the expression of stress-induced transcripts (e.g., FKBP5) among astrocytes and oligodendrocytes from female subjects with OUD. Thus, we describe striatal cell types and leverage these data to gain insights into molecular alterations in human striatum associated with opioid addiction.
2023-11-28 | GSE233279 | GEO
Project description:All drugs of abuse induce long-lasting changes in synaptic transmission and neural circuit function that underlie substance use disorders. Another recently appreciated mechanism of neural circuit plasticity is mediated through activity-regulated changes in myelin that can tune circuit function and influence cognitive behavior1. Here, we explored the role of myelin plasticity in dopaminergic circuity and reward learning. We demonstrate that dopaminergic neuronal activity-regulated myelin plasticity is a key modulator of dopaminergic circuit function and opioid reward. Oligodendroglial lineage cells respond to dopaminergic neuronal activity evoked by either optogenetic stimulation of dopaminergic neurons, optogenetic inhibition of GABAergic neurons, or administration of morphine or cocaine. These oligodendroglial changes are evident selectively within the ventral tegmental area (VTA), but not along the axonal projections in the medial forebrain bundle nor within the target nucleus accumbens (NAc). Genetic blockade of oligodendrogenesis dampens dopamine release dynamics in nucleus accumbens and impairs behavioral conditioning to morphine. Taken together, these findings underscore a critical role for oligodendrogenesis in reward learning and identify dopaminergic neuronal activity-regulated myelin plasticity as an important circuit modification that is required for opioid reward.
2024-02-10 | GSE255072 | GEO