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Arenkiel, B. R.

Publications and source records attributed to Arenkiel, B. R..

13 recordsLinked to original sources

Cross-Species Efficacy of Combinatorial Gene Therapy for Osteoarthritis and Correction of Neuro-Inflammatory Pain Mechanisms

Osteoarthritis is a leading cause of chronic pain and disability, which lacks disease-modifying treatment. Given the complex multi-tissue and multifactorial drivers behind disease progression, effective treatments will require simultaneously targeting several mechanisms underlying joint degeneration and pain. Here, we developed and evaluated a combinatorial gene therapy, consisting of a high-capacity adenoviral vector carrying two therapeutic genes to target distinct pathological mechanisms: inflammation (IL-1Ra) and chondrocyte health (PRG4). Intra-articular delivery of this treatment improved functional, structural, and pain outcomes in murine and equine osteoarthritis models. In addition, treatment normalized inflammatory environments in joint tissues, as well as in the dorsal root ganglia (DRG) known to harbor joint-innervating sensory neurons. Moreover, gene therapy reversed OA-induced molecular signatures of neural hyperexcitability, suggesting amelioration of peripheral sensitization. Collectively, these findings support combinatorial gene therapy as a promising treatment for osteoarthritis, while identifying neuroinflammatory signatures for correction of disease progression and pain. One Sentence SummaryA single intra-articular injection of a combinatorial gene therapy slows OA progression and reduces pain in small and large animal models.

systems biology↗

Paternal behavior is controlled by preoptic Trpc5 neurons

Male parenting behavior is highly conserved and activated only after offspring are born. Here we show that the behavioral switch from infanticide in virgin male mice to caregiving in wild-type sires is associated with enhanced expression and activation of Transient receptor potential channel 5 (Trpc5) in estrogen receptor (Esr1)-expressing neurons in the hypothalamic medial preoptic area (MPOA). While selective deletion of Trpc5 from Esr1MPOA neurons diminishes paternal behavior in sires, overexpression of Trpc5 in these neurons converts the otherwise infanticidal virgin males to exhibit care to pups. Mechanistically, Trpc5-dependent changes in neuronal excitability underlie fatherhood-associated Esr1MPOA neuron plasticity. Notably, Trpc5 overexpression also enhances escape behavior and elicits exploratory diving behavior, suggesting that these neurons control a broader adaptive parenting response in males. These findings establish a Trpc5-dependent MPOA neural signal as a critical regulator of paternal behavior.

neuroscience↗

Selective loss of Primary Cilia and Neurotrophic Signaling in G51D alpha-Synuclein Mice Highlights a Common Pathway to Parkinsons Disease

Parkinsons disease is characterized by dopaminergic neuron loss and accumulation of -synuclein aggregates in the brain. G51D -synuclein knock-in mice provide a genetically and clinically relevant model of disease, exhibiting early olfactory deficits, age-dependent motor impairment, and progressive phospho--synuclein accumulation. In multiple Parkinsons disease models, striatal cholinergic and parvalbumin interneurons, as well as astrocytes, lose primary cilia and the neurotrophic signaling needed to sustain dopaminergic neurons. We show here that G51D--synuclein mice share these phenotypes. Phospho-Ser129 -synuclein accumulation correlates with cilia loss in cholinergic interneurons but not in medium spiny neurons that accumulate higher phospho--synuclein levels. In the piriform cortex, parvalbumin neurons lose primary cilia and downregulate Neurturin, potentially contributing to olfactory dysfunction. Within the peripheral olfactory epithelium, horizontal basal cells lose cilia, whereas multi-ciliated olfactory sensory neuron cilia remain intact. These findings reveal convergent cellular vulnerabilities across Parkinsons disease models and highlight a pathogenic role for impaired ciliary signaling. TeaserLoss of primary cilia may contribute to dopamine neuron loss in both inherited and common Parkinsons disease.

neuroscience↗

Frequency-dependent cerebellar circuits independently gate social vocalizations and movement

Communication depends on precise coordination between motor execution and cognition. Here we reveal that the cerebellum exerts real-time control over social vocalizations in adult mice. Optogenetic activation of excitatory cerebellar output in the superior cerebellar peduncle suppressed ultrasonic vocalizations with frequency-dependent potency while inducing distinct motor phenotypes. Systematic, functional mapping across cerebellar regions and cell types revealed that vocal suppression can occur in the absence of overt motor impairment, suggesting selective control of vocal output beyond gross movement disruption. We identified the periaqueductal gray (PAG), a conserved midbrain vocal control center, as a key downstream mediator of this effect. Deep brain stimulation of the PAG rescued vocal deficits in a model of cerebellar dysfunction without rescuing motor incoordination. These findings define a cerebellar-midbrain pathway that gates vocal behavior and demonstrate that targeted therapeutic neuromodulation can selectively restore communication-related output even in the presence of persistent cerebellar-driven motor deficits.

neuroscience↗

Comparative Analysis of AAV Serotypes for Transduction of Olfactory Sensory Neurons

Olfactory sensory neurons within the nasal epithelium detect volatile odorants and relay odor information to the central nervous system. Unlike other sensory inputs, olfactory sensory neurons interface with the external environment and project their axons directly into the central nervous system. The use of adeno-associated viruses to target these neurons has garnered interest for applications in gene therapy, probing olfactory sensory neuron biology, and modeling disease. To date, there is no consensus on the optimal AAV serotype for efficient and selective transduction of olfactory sensory neurons in vivo. Here we utilized serial confocal imaging and single-nucleus RNA sequencing to evaluate the efficacy of 11 different AAV serotypes in transducing murine olfactory sensory neurons via non-invasive nasal inoculation. Our results reveal that AAV1, while highly effective, exhibited broad tropism, whereas AAV-DJ/8 showed the greatest specificity for olfactory sensory neurons.

neuroscience↗

Multisite Assembly of Gateway Induced Clones (MAGIC): a flexible cloning toolbox withdiverse applications in vertebrate model systems.

Here we present the Multisite Assembly of Gateway Induced Clones (MAGIC) system, which harnesses site-specific recombination-based cloning via Gateway technology for rapid, modular assembly of between 1 and 3 "Entry" vector components, all into a fourth, standard high copy "Destination" plasmid backbone. The MAGIC toolkit spans a range of in vitro and in vivo uses, from directing tunable gene expression, to driving simultaneous expression of microRNAs and fluorescent reporters, to enabling site-specific recombinase-dependent gene expression. All MAGIC system components are directly compatible with existing multisite gateway Tol2 systems currently used in zebrafish, as well as existing eukaryotic cell culture expression Destination plasmids, and available mammalian lentiviral and adenoviral Destination vectors, allowing rapid cross-species experimentation. Moreover, herein we describe novel vectors with flanking piggyBac transposon elements for stable genomic integration in vitro or in vivo when used with piggyBac transposase. Collectively, the MAGIC system facilitates transgenesis in cultured mammalian cells, electroporated mouse and chick embryos, as well as in injected zebrafish embryos, enabling the rapid generation of innovative DNA constructs for biological research due to a shared, common plasmid platform.

molecular biology↗

An Excitatory Projection from the Basal Forebrain to the Ventral Tegmental Area Underlying Anorexia-like Phenotypes

Adaptation to potential threat cues in feeding regulation is key for animal survival. Maladaptation in balancing internal energy needs and external threat cues may result in eating disorders. However, brain mechanisms underlying such maladaptation remain elusive. Here, we identified that the basal forebrain (BF) sends glutamatergic projections to glutamatergic neurons in the ventral tegmental area (VTA). Glutamatergic neurons in both the BF and the VTA displayed correlated responses to various external stressors. Notably, in vivo manipulation of BF terminals in the VTA revealed that the glutamatergic BFVTA circuit reduces appetite, increases locomotion, and elicits avoidance. In consistence, activation of VTA glutamatergic neurons reduced body weight, blunted food motivation, and caused hyperactivity with behavioral signs of anxiety, all hallmarks of typical anorexia phenotypes. Importantly, activation of BF glutamatergic terminals in the VTA reduced dopamine release in the nucleus accumbens (NAc). Collectively, our results point to overactivation of the glutamatergic BFVTA circuit as a potential cause of anorexia-like phenotypes involving reduced dopamine release.

neuroscience↗

Conserved neural dynamics and computations across species in olfaction

Interpreting chemical information and translating it into ethologically relevant output is a common challenge of olfactory systems across species. Are computations performed by olfactory circuits conserved across species to overcome these common challenges? To investigate this, we compared odor responses in the locust antennal lobe (AL) and mouse olfactory bulb (OB). We found that odors activated nearly mutually exclusive neural ensembles during stimulus presentation ( ON response) and after stimulus termination ( OFF response). Strikingly, ON and OFF responses evoked by a single odor were anticorrelated with each other. Inverted OFF responses led to a history-dependent suppression of common ensemble elements, which enhanced contrast between odors experienced close together in time. Notably, odor-specific OFF responses persisted long after odor termination in both AL and OB networks. Taken together, our results reveal key neurodynamic features underlying olfactory computations that are conserved across insect and mammalian olfactory systems.

neuroscience↗

Cell type-specific basal forebrain GABAergic neuronal activity with olfactory task performance, learning, and decision-making

Sensory perception relies on the flexible detection and interpretation of stimuli across variable contexts, conditions, and behavioral states. The basal forebrain is a hub for behavioral state regulation, supplying dense cholinergic and GABAergic projections to various brain regions involved in sensory processing. Of GABAergic neurons in the basal forebrain, parvalbumin (PV) and somatostatin (SST) subtypes serve opposing roles towards regulating behavioral states. To elucidate the role of basal forebrain circuits in sensory-guided behavior, we investigated GABAergic signaling dynamics during odor-guided decision-making. We used fiber photometry to record cell type-specific basal forebrain activity during an odor discrimination task and correlated temporal patterns of PV and SST neuronal activity with olfactory task performance. We found that while both PV-expressing and SST-expressing GABAergic neurons were excited during trial initiation, PV neurons were selectively suppressed by reward whereas SST neurons were excited. Notably, chemogenetic inhibition of BF SST neurons modestly altered decision bias to favor reward-seeking while optogenetic inhibition of BF PV neurons during odor presentations improved discrimination accuracy. Together, these results suggest that the bidirectional activity of GABAergic basal forebrain neuron subtypes distinctly influence perception and decision-making during olfactory guided behavior. SIGNIFICANCE STATEMENTThis study reveals distinct roles for basal forebrain GABAergic neurons in odor perception and odor-guided decision-making. Fiber photometry shows that basal forebrain parvalbumin-expressing neurons are selectively suppressed by rewards, while somatostatin-expressing neurons are activated, establishing the unique recruitment of these GABAergic neurons during behavioral reinforcement. Chemogenetic and optogenetic interventions demonstrate divergent roles for these neuronal subtypes in reward-seeking behavior and odor perception. This research provides new insights into how GABAergic neurons in the basal forebrain shape sensory perception and decision-making.

neuroscience↗

The cerebellum initiates severe tonic-clonic seizures by altering neuronal activity in the ventral posteromedial nucleus (VPM) of the thalamus

Thalamo-cortical networks are central to seizures, yet its unclear how these circuits initiate the seizures. Here, we test the hypothesis that a facial region of the thalamus, the VPM, is a source of convulsive, tonic-clonic seizures. We devised an in vivo optogenetic mouse model to elicit tonic-clonic seizures by driving convergent input to the VPM. With viral tracing, we show dense cerebellar and cerebral cortical afferent input to the VPM. Lidocaine microinfusions into the cerebellar nuclei selectively block seizure initiation. We perform single-unit electrophysiology recordings during awake, convulsive seizures to define the local activity of thalamic neurons before, during, and after seizure onset. We find highly dynamic activity with biphasic properties, raising the possibility that heterogenous activity patterns promote seizures. These data reveal the VPM as a source of tonic-clonic seizures, with cerebellar input providing the predominant signals.

neuroscience↗

A CRISPR toolbox for generating intersectional genetic mice for functional, molecular, and anatomical circuit mapping

BackgroundA full understanding of circuits and cellular mechanisms governing health and disease requires the dissection and multi-faceted study of discrete cell subtypes in developing and adult animal models. Recombinase-driven expression of transgenic response alleles represents a significant and powerful approach to delineate cell populations for functional, molecular, and anatomical study. In addition to single recombinase systems, the expression of two recombinases in distinct, but partially overlapping, populations allow for more defined target expression. Although the application of this method is becoming increasingly popular, the expense and difficulty associated with production of customized intersectional mouse lines have limited widespread application to more common allele manipulations that are often commercially produced at great expense. ResultsWe present a simplified CRISPR toolkit for rapid, inexpensive, and facile intersectional allele production. Briefly, we produced 7 intersectional mouse lines using a dual recombinase system, one mouse line with a single recombinase system, and three embryonic stem (ES) cell lines that are designed to study how functional, molecular, and anatomical features relate to each other in building circuits that underlie physiology and behavior. As a proof-of-principle, we applied three of these lines to different neuronal populations for anatomical mapping and functional in vivo investigation of respiratory control. We also generated a mouse line with a single recombinase-responsive allele that controls the expression of the calcium sensor Twitch-2B. This mouse line was applied globally to study the effects of follicle stimulating hormone (FSH) and luteinizing hormone (LH) on calcium release in the ovarian follicle. ConclusionsLines presented here are representative examples of outcomes possible with the successful application of our genetic toolkit for the facile development of diverse, modifiable animal models. This toolkit will allow labs to create single or dual recombinase effector lines easily for any cell population or subpopulation of interest when paired with the appropriate Cre and FLP recombinase mouse lines or viral vectors. We have made our tools and derivative intersectional mouse and ES cell lines openly available for non-commercial use through publicly curated repositories for plasmid DNA, ES cells, and transgenic mouse lines.

genetics↗

Dynamic cholinergic tone in the basal forebrain reflects reward-seeking and reinforcement during olfactory behavior

Sensory perception underlies how we internalize and interact with the external world. In order to adapt to changing circumstances and interpret signals in a variety of contexts, sensation needs to be reliable, but perception of sensory input needs to be flexible. An important mediator of this flexibility is top-down regulation from the cholinergic basal forebrain. Basal forebrain projection neurons serve as pacemakers and gatekeepers for downstream neural networks, modulating circuit activity across diverse neuronal populations. This top-down control is necessary for sensory cue detection, learning, and memory, and is disproportionately disrupted in neurodegenerative diseases associated with cognitive decline. Intriguingly, cholinergic signaling acts locally within the basal forebrain to sculpt the activity of basal forebrain output neurons. To determine how local cholinergic signaling impacts basal forebrain output pathways that participate in top-down regulation, we sought to define the dynamics of cholinergic signaling within the basal forebrain during motivated behavior and learning. Towards this, we utilized fiber photometry and the genetically encoded acetylcholine indicator GAChR2.0 to define temporal patterns of cholinergic signaling in the basal forebrain during olfactory-guided, motivated behaviors and learning. We show that cholinergic signaling reliably increased during reward-seeking behaviors but was strongly suppressed by reward delivery in a go/no-go, olfactory-cued discrimination task. The observed transient reduction in cholinergic tone was mirrored by a suppression in basal forebrain GABAergic neuronal activity. Together, these findings suggest that cholinergic tone in the basal forebrain changes rapidly to reflect rewardseeking behavior and positive reinforcement to impact basal forebrain circuit activity.

neuroscience↗

ANKLE2, a target of Zika virus, controls asymmetric cell division of neuroblasts and uncovers a novel microcephaly pathway

Neuroblasts in flies divide asymmetrically by establishing polarity, distributing cell fate determinants asymmetrically, and positioning their spindle for cell division. The apical complex contains aPKC, Bazooka (Par3), and Par6, and its activity depends on L(2)gl. We show that Ankle2 interacts with L(2)gl and affects aPKC. Reducing Ankle2 levels disrupts ER and nuclear envelope morphology, releasing the kinase Ballchen/VRK1 into the cytosol. These defects are associated with reduced phosphorylation of aPKC, disruption of Par complex localization, and spindle alignment defects. Importantly, removal of one copy of ballchen/VRK1 or l(2)gl suppresses the loss of Ankle2 and restores viability and brain size. The Zika virus NS4A protein interacts with Drosophila Ankle2 and VRK1 in dividing neuroblasts. Human mutational studies implicate this neural cell division pathway in microcephaly and motor neuron disease. In summary, NS4A, ANKLE2, VRK1 and LLGL1 define a novel pathway that impinges on asymmetric determinants of neural stem cell division.

genetics↗