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Sidhu, H.

Publications and source records attributed to Sidhu, H..

5 recordsLinked to original sources

Functional remodeling of the parasubthalamic nucleus drives alcohol drinking escalation in dependence

The neurocircuitry changes mediating the development and maintenance of an alcohol use disorder are complex and dynamic. The parasubthalamic nucleus (PSTN), a small nucleus of the posterior lateral hypothalamus best known for suppressing appetite, is interconnected with brain regions disrupted in addiction; yet its potential role in the regulation of alcohol consumption had never been examined. Here we show that the PSTN exerts potent control over alcohol drinking in mice. Remarkably, the influence of endogenous PSTN activity on voluntary alcohol consumption switches from inhibitory to stimulatory upon induction of alcohol dependence. Among PSTN cells, Crh neurons represent a unique subpopulation that promotes alcohol drinking and fires more in dependent mice. Alcohol intake escalation driven by PSTN Crh neurons involves thalamic output and behavioral disinhibition. Based on our results, PSTN Crh neurons could represent a critical node in the brain circuitry overactive in alcohol addiction driven by reward seeking in humans.

neuroscience↗

Bacteriophage-Loaded Microneedle Patches for Targeted andMinimally Disruptive Foodborne Pathogen Decontamination

Antibacterial additive use has surged due to rising incidences of food contamination, despite concerns over antibiotic resistance. Bacteriophage (bacterial viruses) represent a unique and promising opportunity as antibacterial agents, offering targeted bacterial lysis while being food safe. However, their commercial success has been limited by the significant diffusion barriers they face within food, preventing effective delivery at contamination sites. Here, we introduce bacteriophage-loaded microneedle patches that enable targeted phage delivery directly within food, eliminating internal pathogens in a minimally disruptive manner. The application of microneedles within food is first explored. The platform is then substantiated by comparing performance in raw beef and cooked chicken, where we achieved up to 3-logs reduction in Escherichia coli, thus providing complete decontamination according to regulatory limits. In contrast, conventional surface application of the same phage failed to provide significant decontamination. To ensure broad applicability, phage cocktails were also loaded into microneedles to demonstrate polymicrobial decontamination against other common food contaminants including Salmonella. This platform can also be adapted to extend food shelf-life by targeting spoilage-inducing bacteria.

bioengineering↗

Mouse parasubthalamic Crh neurons drive alcohol drinking escalation and behavioral disinhibition

Corticotropin-releasing factor (CRF, encoded by Crh) signaling is thought to play a critical role in the development of excessive alcohol drinking and the emotional and physical pain associated with alcohol withdrawal. Here, we investigated the parasubthalamic nucleus (PSTN) as a potential source of CRF relevant to the control of alcohol consumption, affect, and nociception in mice. We identified PSTN Crh neurons as a neuronal subpopulation that exerts a potent and unique influence on behavior by promoting not only alcohol but also saccharin drinking, while PSTN neurons are otherwise known to suppress consummatory behaviors. Furthermore, PSTN Crh neurons are causally implicated in the escalation of alcohol and saccharin intake produced by chronic intermittent ethanol (CIE) vapor inhalation, a mouse model of alcohol use disorder. In contrast to our predictions, the ability of PSTN Crh neurons to increase alcohol drinking is not mediated by CRF1 signaling. Moreover, the pattern of behavioral disinhibition and reduced nociception driven by their activation does not support a role of negative reinforcement as a motivational basis for the concomitant increase in alcohol drinking. Finally, silencing Crh expression in the PSTN slowed down the escalation of alcohol intake in mice exposed to CIE and accelerated their recovery from withdrawal-induced mechanical hyperalgesia. Altogether, our results suggest that PSTN Crh neurons may represent an important node in the brain circuitry linking alcohol use disorder with sweet liking and novelty seeking.

neuroscience↗

Chemogenetic stimulation of mouse central amygdala corticotropin-releasing factor neurons: Effects on cellular and behavioral correlates of alcoholdependence

BackgroundCorticotropin-releasing factor (CRF) signaling in the central nucleus of the amygdala (CeA) plays a critical role in rodent models of excessive alcohol drinking. However, the source of CRF acting in the CeA during alcohol withdrawal remains to be identified. In the present study, we hypothesized that CeA CRF interneurons may represent a behaviorally relevant source of CRF to the CeA increasing motivation for alcohol via negative reinforcement. MethodsWe tested this hypothesis in male mice and used chemogenetics to stimulate CeA CRF neurons in vitro and in vivo. ResultsWe first observed that Crh mRNA expression in the anterior part of the mouse CeA, at the junction with the interstitial nucleus of the posterior limb of the anterior commissure, correlates positively with alcohol intake in C57BL/6J males with a history of chronic binge drinking. We then found that chemogenetic activation of CeA CRF neurons in Crh-IRES-Cre mouse brain slices increases gamma-aminobutyric acid (GABA) release in the medial CeA in part via CRF1 receptor activation, indicating local CRF release. While chemogenetic stimulation of CeA CRF neurons exacerbated novelty-induced feeding suppression, as seen in C57BL/6J males withdrawn from chronic intermittent alcohol inhalation, it had no effect on voluntary alcohol consumption, following either acute or chronic manipulation. ConclusionsAltogether, these findings indicate that hyperactivity of CeA CRF neurons may contribute to elevated CeA GABA levels and negative affect during alcohol withdrawal but is not sufficient to drive alcohol intake escalation in dependent mice.

neuroscience↗

Single-cell whole-brain imaging and network analysis provide evidence of the three-stage hypothesis of addiction

Three main theories of the neurobiology of addiction have been proposed: (1) incentive salience mediated by a brainstem-striatal network, (2) habit mediated by a cortico-striato-thalamic network, and (3) hedonic allostasis mediated by an extended amygdala network. Efforts have been made to reconcile these theories within a three-stage model, but the relevance of each theory remains controversial. We tested the validity of each theory with a single dataset using unbiased single-cell whole-brain imaging and data-driven analyses of neuronal activity in a mouse model of alcohol use disorder. Abstinence in alcohol dependent mice decreased brain modularity and resulted in clustering of brain regions that correspond to each stage of the three-stage theory of addiction. Furthermore, we identified several brain regions whose activity highly predicted addiction-like behaviors and \"hub\" regions that may drive neural activation during abstinence. These results validate the three-stage theory of addiction and identify potential target regions for future study.

neuroscience↗