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Golden, S.

Publications and source records attributed to Golden, S..

9 recordsLinked to original sources

Social agency buffers pain sensitivity during a critical window following spared nerve injury

BackgroundSocial buffering of pain, where social contact blunts pain intensity, is well established. However, the degree to which agency over social contact, rather than passive social exposure alone, modifies pain intensity or social behavior is unclear. MethodsUsing a social operant self-administration procedure in which mice lever-press for access to their pair-housed partner, we show that voluntary social engagement gates pain after spared nerve injury (SNI). After 8 days of training, mice underwent SNI and then regained access to social self-administration either 1 day (Early) or 5 days (Delayed) following surgery. We compared these mice to groups without social self-administration access, non-contingent social-access, and food self-administration. We assessed changes in pain, or mechanical allodynia, via the von Frey test. ResultsEarly access to social self-administration after SNI preserved pre-injury social reinforcement and buffered pain. Delayed access similarly preserved social reinforcement but failed to buffer allodynia, revealing an early post-injury critical window for social buffering of pain. Females were more sensitive to both SNI and disrupted social access, while males maintained social reward-seeking after SNI when given early access and showed robust social buffering of pain. Non-contingent (involuntary) social self-administration did not modify pain, nor did food self-administration. ConclusionsThere is an early critical window during which voluntary social interactions buffer pain after nerve injury. These results highlight social reward agency and proximity to injury as key variables, since pain outcomes do not generalize to food reward, non-contingent social reward, or delayed access to social reward.

neuroscience↗

Subcortical recruitment dissociates isoflurane emergence from distinct wakeful states in mice

Emergence from general anesthesia, defined by a recovery of consciousness to the wakeful state, is a clinically consequential state transition that remains a passive process dependent on drug clearance. Despite the critical use of anesthesia, the neural circuitry underlying behavioral recovery remains poorly defined. Here, we map whole-brain neural activity during emergence from isoflurane anesthesia in mice using Fos immunolabeling, tissue clearing, and light-sheet microscopy. This approach enables unbiased quantification of neural activity at cellular resolution across the intact whole brain and supports subsequent network analysis. Rather than resembling wakefulness, emergence exhibits widespread cortical suppression alongside selective activation of discrete subcortical nuclei. This pattern of activity includes both previously implicated arousal-related regions and lesser-studied structures linked to respiratory, autonomic, interoceptive, and cerebellar function. By comparing emergence to two behaviorally distinct wakeful control states, we find that control state selection substantially shapes interpretation of whole-brain activity maps. This establishes dual-state comparisons as a broadly useful strategy for state-dependent circuit mapping. Functional network analysis further elucidates candidate central regions that strongly covary together during emergence, with the most integrated region being the ventral orbital cortex. This approach allows for targeted causal investigation, linking brain-wide circuit discovery with future hypothesis-driven mechanistic interrogation. Together, we find that emergence from isoflurane anesthesia reflects selective subcortical recruitment rather than broad global reactivation toward wakefulness. Significance StatementMillions of people undergo general anesthesia each year. While anesthetic unconsciousness is induced rapidly, emergence from altered consciousness is unpredictable. Neural mechanisms that underlie behavioral emergence remain poorly defined. Using whole-brain Fos mapping at cellular resolution, we found that emergence from isoflurane anesthesia is characterized by widespread cortical suppression alongside selective activation of discrete subcortical, autonomic, hindbrain, and cerebellar nuclei. This selective systems-level activity pattern identifies behavioral emergence as more than a simple global return toward wakefulness and highlights underappreciated neural circuitry involved in post-anesthetic recovery. Network analysis of the Fos maps further identifies candidate regions for targeted causal investigation of emergence-related regions.

neuroscience↗

Opioid-driven disruption of the septal complex reveals a role for neurotensin- expressing neurons in withdrawal

Because opioid withdrawal is an intensely aversive experience, persons with opioid use disorder (OUD) often relapse to avoid it. The lateral septum (LS) is a forebrain structure that is important in aversion processing, and previous studies have linked the lateral septum (LS) to substance use disorders. It is unclear, however, which precise LS cell types might contribute to the maladaptive state of withdrawal. To address this, we used single-nucleus RNA-sequencing to interrogate cell type specific gene expression changes induced by chronic morphine and withdrawal. We discovered that morphine globally disrupted the transcriptional profile of LS cell types, but Neurotensin-expressing neurons (Nts; LS-Nts neurons) were selectively activated by naloxone. Using two-photon calcium imaging and ex vivo electrophysiology, we next demonstrate that LS-Nts neurons receive enhanced glutamatergic drive in morphine-dependent mice and remain hyperactivated during opioid withdrawal. Finally, we showed that activating and silencing LS-Nts neurons during opioid withdrawal regulates pain coping behaviors and sociability. Together, these results suggest that LS-Nts neurons are a key neural substrate involved in opioid withdrawal and establish the LS as a crucial regulator of adaptive behaviors, specifically pertaining to OUD.

neuroscience↗

An arginine-rich nuclear localization signal (ArgiNLS) strategy for streamlined image segmentation of single-cells

High-throughput volumetric fluorescent microscopy pipelines can spatially integrate whole-brain structure and function at the foundational level of single-cells. However, conventional fluorescent protein (FP) modifications used to discriminate single-cells possess limited efficacy or are detrimental to cellular health. Here, we introduce a synthetic and non-deleterious nuclear localization signal (NLS) tag strategy, called Arginine-rich NLS (ArgiNLS), that optimizes genetic labeling and downstream image segmentation of single-cells by restricting FP localization near-exclusively in the nucleus through a poly-arginine mechanism. A single N-terminal ArgiNLS tag provides modular nuclear restriction consistently across spectrally separate FP variants. ArgiNLS performance in vivo displays functional conservation across major cortical cell classes, and in response to both local and systemic brain wide AAV administration. Crucially, the high signal-to-noise ratio afforded by ArgiNLS enhances ML-automated segmentation of single-cells due to rapid classifier training and enrichment of labeled cell detection within 2D brain sections or 3D volumetric whole-brain image datasets, derived from both staining-amplified and native signal. This genetic strategy provides a simple and flexible basis for precise image segmentation of genetically labeled single-cells at scale and paired with behavioral procedures. Significance StatementQuantifying labeled cells in fluorescent microscopy is a fundamental aspect of modern biology. Critically, the use of short nuclear localization sequences (NLS) is a key genetic modification for discriminating single-cells labeled with fluorescent proteins (FPs). However, mainstay NLS approaches typically localize proteins to the nucleus with limited efficacy, while alternative non-NLS tag strategies can enhance efficacy at the cost of cellular health. Thus, quantitative cell counting using FP labels remains suboptimal or not compatible with health and behavior. Here, we present a novel genetic tagging strategy - named ArgiNLS - that flexibly and safely achieves FP nuclear restriction across the brain to facilitate machine learning-based segmentation of single-cells at scale, delivering a timely update to the behavioral neuroscientists toolkit.

neuroscience↗

Post-Mating Inhibition of Female Sexual Drive via Heterogeneous Neuronal Ensembles in the Medial Preoptic Area

Male ejaculation acutely suppresses sexual motivation in male mice. In contrast, relatively little is known about how male ejaculation affects sexual motivation and sexual behavior in female mice. How the brain responds to completion of mating is also unclear. Here, by using self-paced mating assay, we first demonstrate that female mice show decreased sexual motivation acutely after experiencing male ejaculation. By using brain-wide analysis of activity-dependent labeling, we next pinpointed the medial preoptic area as a brain region strongly activated during the post-ejaculatory period. Furthermore, using freely moving in vivo calcium imaging to compare neural activity of inhibitory and excitatory neurons in the medial preoptic area, we revealed that a subset of the neurons in this region respond significantly and specifically to male ejaculation but not to female-to-male sniffing or to male mounting. While there were excitatory and inhibitory neurons that showed increased response to male ejaculation, the response magnitude as well as the proportion of neurons responding to the event was significantly larger in the inhibitory neuron population. Next, by unbiased classification of their responses, we also found a subpopulation of neurons that increase their activity late after the onset of male ejaculation. These neurons were all inhibitory indicating that male ejaculation induces a prolonged inhibitory activity in the medial preoptic area. Lastly, we found that chemogenetic activation of medial preoptic area neurons that were active during post-ejaculatory period, but not during appetitive or consummatory periods, were sufficient to suppress female sexual motivation. Together, our data illuminate the importance of medial preoptic area as a brain node which encodes a negative signal that sustains low sexual motivation state after the female mice experience ejaculation. HighlightsO_LIFemale mice show decreased sexual motivation in the post-ejaculatory period. C_LIO_LIA subset of MPOA neurons in female respond specifically to male ejaculation. C_LIO_LIMale-ejaculation evokes persistent activity in MPOA inhibitory neurons in females. C_LIO_LIActivation of a subset of MPOA neurons is sufficient to suppress female sexual motivation. C_LI

neuroscience↗

Dynamic Sex Differences in Reactive and Appetitive Aggression

Aggression is an evolutionarily conserved, adaptive component of social behavior. Studies in male mice illustrate that aggression is influenced by numerous factors including the degree to which an individual finds aggression rewarding and will work for access to attack and subordinate mice. While such studies have expanded our understanding of the molecular and circuit mechanisms of male aggression very little is known about female aggression, owed in part to limited availability of valid mouse models in females. Here we use an ethologically relevant model of male vs. female aggression by pair housing adult male and female outbred CFW mice with opposite sex cage mates. We assess reactive (defensive) aggression in the resident intruder (RI) test and appetitive (rewarding) aggression in the aggression conditioned place preference (CPP) and operant self-administration (SA) tests. Our results show dramatic sex differences in both qualitative and quantitative aspects of reactive vs. appetitive aggression. Males exhibit more wrestling and less investigative behavior during RI, find aggression rewarding and will work for access to a subordinate to attack. Females exhibit more bites, alternate between aggressive behaviors and investigative behaviors more readily during RI, however, they do not find aggression to be rewarding or reinforcing. These results establish sex differences in aggression in mice, providing an important resource for the field to better understand the circuit and molecular mechanisms of aggression in both sexes.

neuroscience↗

Distinct properties in ventral pallidum projection neuron subtypes

The ventral pallidum (VP) is central to reward seeking and withdrawal from drugs of abuse. A characteristic of the VP is the diversity of its projection targets. Yet, it remains unknown whether different VP projections also differ in other aspects, such as their transcriptome, physiology and relevance to drug reward. In this study we perform a multimodal dissection of four major projections of the VP - to the lateral hypothalamus (VP[->]LH), ventral tegmental area (VP[->]VTA), lateral habenula (VP[->]LHb) and mediodorsal thalamus (VP[->]MDT) - with physiological, anatomical, genetic and behavioral tools and show significant differences between projections in all aspects. Specifically, the VP[->]LH and VP[->]VTA projections show minimal overlap and stand out as having opposite properties - VP[->]LH neurons show higher excitability compared to VP[->]VTA neurons, different pattern of inputs and differentially expressed genes. Moreover, inhibition of VP[->]LH projections diminishes, while inhibition of VP[->]VTA enhances cocaine preference after cocaine withdrawal. This demonstrates that VP projections are heterogenous neuron populations with different roles in cocaine withdrawal.

neuroscience↗

Hidden conformations differentiate day and night in a circadian pacemaker

The AAA+ protein KaiC is the central pacemaker for cyanobacterial circadian rhythms. Composed of two hexameric rings with tightly coupled activities, KaiC undergoes changes in autophosphorylation on its C-terminal (CII) domain that restrict binding of of clock proteins on its N-terminal (CI) domain to the evening. Here, we use cryo-electron microscopy to investigate how daytime and nighttime states of CII regulate KaiB binding to CI. We find that the CII hexamer is destabilized during the day but takes on a rigidified C2-symmetric state at night,concomitant with ring-ring compression. Residues at the CI-CII interface are required for phospho-dependent KaiB association, coupling ATPase activity on CI to cooperative KaiB recruitment. Together these studies reveal how daily changes in KaiC phosphorylation regulate cyanobacterial circadian rhythms. One-Sentence SummaryCryo-EM structures of KaiC in its day and night states reveal the structural basis for assembly of clock regulatory complexes.

biochemistry↗

Orexin signaling in GABAergic lateral habenula neurons modulates aggressive behavior

Heightened aggression is characteristic of multiple neuropsychiatric disorders and can have a wide variety of negative effects on patients, their families, and the public. Recent studies in humans and animals have implicated brain reward circuits in aggression and suggest that, in subsets of aggressive individuals, repeated domination of subordinate social targets is reinforcing. Here, we show that orexin neurons originating from the lateral hypothalamus activate a small population of GABAergic interneurons in the lateral habenula (LHb) via orexin receptor 2 (OxR2) to promote aggression and conditioned place preference (CPP) for aggression-paired contexts. Our study suggests that the orexin system is a potential target for the development of novel therapies aimed at reducing aggressive behaviors and provides the first functional evidence of a local inhibitory circuit within the LHb.

neuroscience↗