Single nuclei transcriptomics in human and non-human primate striatum implicates neuronal DNA damage and proinflammatory signaling in opioid use disorder

Abstract

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.

Integrative multi-dimensional characterization of striatal projection neuron heterogeneity in adult brain

“…To harmonize annotations of striatal projection neuron subtypes across species and datasets, we analyzed eight published, annotated datasets in an unbiased manner, representing the broadest overview of single-nuclei RNA-seq and ATAC-seq data sampled from each species: mouse 45–47,53 , rat 51 , rhesus macaque 48 , and human 49,50,54 . The inclusion criteria for these comparative analyses are: 1) publicly availability of the data, 2) the data are annotated, 3) inclusion of single-cell or nuclei RNA-seq or ATAC-seq approaches, 4) from any striatal subregion, and 5) from a mammal.…”

Chst9Marks a Spatially and Transcriptionally Unique Population ofOprm1-Expressing Neurons in the Nucleus Accumbens

“…While this division is critical for understanding striatal physiology 25 , circuitry 26 , and molecular responses to drugs of abuse [27][28][29] , both cell populations express Oprm1 30 and contribute to opioidinduced behaviors 31 . Further, recent single nucleus RNA sequencing (snRNA-seq) studies have revealed unexpected heterogeneity in MSNs within the NAc and broader striatum, with multiple subtypes of Drd1 and Drd2 expressing MSNs present in the mouse 32 , rat [33][34][35] , monkey 36,37 , and human NAc 37,38 . Strikingly, NAc MSN subtypes exhibit highly variable expression of Oprm1 34 , highlighting the need for further investigation into the roles of distinct MSN subclasses in opioid action.…”

Chst9 marks a spatially and transcriptionally unique population of Oprm1-expressing neurons in the nucleus accumbens

“…While this division is critical for understanding striatal physiology [ 25 ], circuitry [ 26 ], and molecular responses to drugs of abuse [ 27 – 29 ], both cell populations express Oprm1 [ 30 ] and contribute to opioid-induced behaviors [ 31 ]. Further, recent single nucleus RNA sequencing (snRNA-seq) studies have revealed unexpected heterogeneity in MSNs within the NAc and broader striatum, with multiple subtypes of Drd1 and Drd2 expressing MSNs present in the mouse [ 32 ], rat [ 33 – 35 ], monkey [ 36 , 37 ], and human NAc [ 37 , 38 ]. Strikingly, NAc MSN subtypes exhibit highly variable expression of Oprm1 [ 34 ], highlighting the need for further investigation into the roles of distinct MSN subclasses in opioid action.…”