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Centanni, S. W.

Publications and source records attributed to Centanni, S. W..

7 recordsLinked to original sources

HERO: A hierarchy-aware analysis pipeline for reducing and refining whole-brain atlas-mapped cellular datasets

Advances in high-throughput mesoscale microscopy and machine learning-based image analysis pipelines have made unbiased whole-brain imaging widely accessible. However, translating the resulting atlas-mapped datasets into biologically meaningful results remains a substantial barrier owing to their sheer magnitude and complex hierarchical organization. Consequently, reporting structure and analysis methods vary widely across studies, undermining rigor and reproducibility. To address this, we developed a user-friendly data reduction workflow, HERO (Hierarchy-aware Expression Region Organization), designed to perform hierarchy-aware selection, refinement, ranking, and visualization of whole-brain cell detection datasets. The workflow is customizable to specific needs, requires minimal coding experience, and outputs transparent, curated results. HERO is designed to function as a seamless plug-in within larger-scale whole-brain cell-detection analysis pipelines, providing efficient, unbiased region selection to streamline subsequent statistical analyses and comparative evaluations. Although HERO is developed with mouse cell-detection datasets, it can, in principle, be applied to any atlas-mapped dataset that contains hierarchical information. In sum, HERO offers a standardized analysis workflow to reduce whole-brain cell-detection datasets, transforming raw regional cell counts into curated results and advancing the effectiveness, interpretability, and accessibility of whole-brain imaging in neuroscience.

neuroscience↗

Fiber photometry analysis for spontaneous dopamine signals: The z-scored data are not the data

Fluorescent sensors have revolutionized the measurement of molecules in the brain, and the dLight dopamine sensor has been used extensively to examine reward- and cue-evoked dopamine release, but only recently has the field turned its attention to spontaneous release events. Analysis of spontaneous events typically requires evaluation of hundreds of events over minutes to hours, and the most common method of analysis, z-scoring, was not designed for this purpose. Here, we compare the accuracy and reliability of three different analysis methods to identify pharmacologically induced changes in dopamine release and uptake in freely moving C57BL/6J mice. The D1-like receptor antagonist SCH23390 was used to prevent dLight sensors from interacting with dopamine in the extracellular space, while cocaine was used to inhibit uptake and raclopride to increase release of dopamine in the nucleus accumbens. We examined peak-to-peak frequency, peak amplitude, and width, the time spent above an established cutoff. The three methods were 1) the widely-used "Z-Score Method", which automatically smooths baseline drift and normalizes recordings using signal-to-noise ratios, 2) a "Manual Method", in which local baselines were adjusted manually and individual cutoffs were determined for each subject, and 3) the "Prominence Method" that combines z-scoring with prominence assessment to tag individual peaks, then returns to the preprocessed data for kinetic analysis. First, SCH23390 drastically reduced the number of signals detected as expected, but only when the Manual Method was used. Z-scoring failed to identify any changes, due to its amplification of noise when signals were diminished. Cocaine increased signal width as expected using the Manual and Prominence Methods, but not the Z-Score Method. Finally, raclopride- induced increases in amplitude were correctly identified by the Manual and Prominence Methods. The Z-Score Method failed to identify any of the changes in dopamine release and uptake kinetics. Thus, analysis of spontaneous dopamine signals requires assessment of the %{Delta}F/F values, ideally using the Manual Method, and the use of z- scoring is not appropriate. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=137 SRC="FIGDIR/small/639080v1_ufig1.gif" ALT="Figure 1"> View larger version (21K): org.highwire.dtl.DTLVardef@1687207org.highwire.dtl.DTLVardef@165fa1org.highwire.dtl.DTLVardef@e06800org.highwire.dtl.DTLVardef@cbf31e_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

A stress-activated mid-insula to BNST pathway regulates susceptibility to abstinence-induced negative affect in female mice

Stress is central to many neuropsychiatric conditions, including alcohol use disorder (AUD). Stress influences the initiation and continued use of alcohol, the progression to AUD, and relapse. Identifying the neurocircuits activated during stress, and individual variability in these responses is critical for developing new treatment targets for AUD, particularly to mitigate stress-induced relapse. Using a longitudinal approach, this study examined the relationship between sub-chronic stress exposure and negative affect during protracted abstinence following chronic ethanol exposure. Sub-chronic restraint stress heightened negative affect-like behavior in protracted abstinence. Interestingly, this was driven by a subset of "stress-susceptible" female mice. We examined the mid-insula, a hub in the brains salience network, as a driver of this effect, given its role in emotional regulation and links to alcohol craving, consumption, and abstinence-induced negative affect. Mid-insula GCaMP fiber photometry revealed that GCaMP activity during stress exposure was positively correlated with activity during the novelty-suppressed feeding test (NSFT) two weeks into abstinence. A distinct subset of mice exhibited increasing activity during the consummatory phase, implicating the mid-insula as a neural basis for heightened negative affect in abstinence. Chemogenetic inhibition of mid-insula neurons projecting to the dorsal BNST during stress disrupted the emergence of stress susceptibility, highlighting this circuit as a key determinant of susceptibility to abstinence-induced negative affect. These outcomes were female-specific, addressing a critical gap in understanding AUD risk in women. Furthermore, female mice exhibited higher struggling behavior during stress than males. However, this effect was blocked by chemogenetic inhibition of the insula-BNST pathway during stress. By linking pre-alcohol stress response with abstinence outcomes, this work positions the insula-BNST pathway as a potential AUD circuit activity biomarker and therapeutic target.

neuroscience↗

Kappa Opioid Receptors Negatively Regulate Real Time Spontaneous Dopamine Signals by Reducing Release and Increasing Uptake

AbstractThe role of the dynorphin/kappa opioid receptor (KOR) system in dopamine (DA) regulation has been extensively investigated. KOR activation reduces extracellular DA concentrations and increases DA transporter (DAT) activity and trafficking to the membrane. To explore KOR influences on real-time DA fluctuations, we used the photosensor dLight1.2 with fiber photometry in the nucleus accumbens (NAc) core of freely moving male and female C57BL/6 mice. First, we established that the rise and fall of spontaneous DA signals were due to DA release and reuptake, respectively. Then mice were systemically administered the KOR agonist U50,488H (U50), with or without pretreatment with the KOR antagonist aticaprant (ATIC). U50 reduced both the amplitude and width of spontaneous signals in males, but only reduced width in females. Further, the slope of the correlation between amplitude and width was increased in both sexes, suggesting that DA uptake rates were increased. U50 also reduced the frequency of signals in both males and females. All effects of KOR activation were stronger in males. Overall, KORs exerted significant inhibitory control over spontaneous DA signaling, acting through at least three mechanisms - inhibiting DA release, promoting DAT-mediated uptake, and reducing the frequency of signals.

neuroscience↗

High Fat Diet Blunts Stress-Induced Hypophagia and Activation of Glp1r Dorsal Lateral Septum Neurons in Male but not in Female Mice

While stress typically reduces caloric intake (hypophagia) in chow-fed rodents, presentation of palatable, high calorie substances during stress can increase caloric consumption (i.e. "comfort feeding") and promote obesity. However, little is known about how obesity itself affects feeding behavior in response to stress and the mechanisms that can influence stress-associated feeding in the context of obesity. We show that lean male mice display the expected hypophagic response following acute restraint stress, but obese male mice are resistant to this acute stress-induced hypophagia. Activation of the glucagon-like peptide-1 (Glp1) receptor (Glp1r) in various brain regions leads to hypophagia in response to stress. Here we show that Glp1r-positive neurons in the dorsal lateral septum (dLS) are robustly activated during acute restraint stress in lean but not in obese male mice. This raises the possibility that activation of dLS Glp1r neurons during restraint stress contributes to subsequent hypophagia. Supporting this, we show that chemogenetic inhibition of dLS Glp1r neurons attenuates acute restraint stress hypophagia in male mice. Surprisingly, we show that both lean and obese female mice are resistant to acute restraint stress-induced hypophagia and activation of dLS Glp1r neurons. Taken together, these results suggest that dLS Glp1r neurons contribute to the hypophagic response to acute restraint stress in male mice, but not in female mice, and that obesity disrupts this response in male mice. Broadly, these findings show sexually dimorphic mechanisms and feeding behaviors in lean vs. obese mice in response to acute stress.

neuroscience↗

PiRATeMC: A highly flexible, scalable, and affordable system for obtaining high quality video recordings for behavioral neuroscience.

With the recent development and rapidly accelerating adoption of machine-learning based rodent behavioral tracking tools such as DeepLabCut, there is an unmet need for a method of acquiring video data that is scalable, flexible, and affordable. Many experimenters use webcams, GoPros, or other commercially available cameras that are not only relatively expensive, but offer very little flexibility over recording parameters. These cameras are not ideal for recording many types of behavioral experiments, and can lead to suboptimal video quality. Furthermore when using relatively affordable commercially available products, it is a challenge, if not impossible, to synchronize multiple cameras with each other, or to interface with third-party equipment (for example, receiving a simple trigger to simultaneously start recording, or acting as a microcontroller for closed-loop experiments). We have developed an affordable ecosystem of behavioral recording equipment, PiRATeMC (Pi-based Remote Acquisition Technology for Motion Capture), that relies on Raspberry Pi Camera Boards that are able to acquire high quality recordings in bright light, low light, or dark conditions under infrared light. PiRATeMC offers users control over nearly every recording parameter, and can be fine-tuned to produce optimal video data in any behavioral arena. This setup can easily be scaled up and synchronously controlled in clusters via a self-contained network to record a large number of simultaneous behavioral sessions without burdening institutional network infrastructure. Furthermore, the Raspberry Pi is an excellent platform for novice and inexperienced programmers interested in using an open-source recording system, with a large online community that is very active in developing novel open-source tools. It easily interfaces with Arduinos and other microcontrollers, allowing simple synchronization and interfacing of video recording with nearly any behavioral equipment using GPIO pins to send or receive 3.3V or 5V (TTL) signals, I2C, or serial communication.

neuroscience↗

Targeting Diacylglycerol Lipase to Reduce AlcoholConsumption

Alcohol use disorder (AUD) is associated with substantial morbidity, mortality, and societal cost, and pharmacological treatment options for AUD are limited. The endogenous cannabinoid (eCB) signaling system is critically involved in reward processing and alcohol intake is positively correlated with release of the eCB ligand 2-Arachidonoylglycerol (2-AG) within reward neurocircuitry. Here we show that genetic and pharmacological inhibition of diacylglycerol lipase (DAGL), the rate limiting enzyme in the synthesis of 2-AG, reduces alcohol consumption in a variety of preclinical models ranging from a voluntary free-access model to aversion resistant-drinking, and dependence-like drinking induced via chronic intermittent ethanol vapor exposure in mice. DAGL inhibition also prevented ethanol-induced suppression of GABAergic transmission onto midbrain dopamine neurons, providing mechanistic insight into how DAGL inhibition could affect alcohol reward. Lastly, DAGL inhibition during either chronic alcohol consumption or protracted withdrawal was devoid of anxiogenic and depressive-like behavioral effects. These data suggest reducing 2-AG signaling via inhibition of DAGL could represent a novel approach to reduce alcohol consumption across the spectrum of AUD severity.

neuroscience↗