Neurology Commons^™

Inhibition Of Soluble Epoxide Hydrolase Confers Neuroprotection And Restores Microglial Homeostasis In A Tauopathy Mouse Model, Shuo Wang, Chuangye Qi, Chetan Rajpurohit, Baijayanti Ghosh, Wen Xiong, Baiping Wang, Yanyan Qi, Sung Hee Hwang, Bruce D Hammock, Hongjie Li, Li Gan, Hui Zheng

Center on Aging Staff Publications

Background: The epoxyeicosatrienoic acids (EETs) are derivatives of the arachidonic acid metabolism with anti-inflammatory activities. However, their efficacy is limited due to the rapid hydrolysis by soluble epoxide hydrolase (sEH). Inhibition of sEH has been shown to stabilize the EETs and reduce neuroinflammation in Aβ mouse models of Alzheimer's disease (AD). However, the role of the sEH-EET signaling pathway in other CNS cell types and neurodegenerative conditions are less understood.

Methods: Here we investigated the mechanisms and functional role of the sEH-EET axis in tauopathy by treating PS19 mice with a small molecule sEH inhibitor TPPU and by crossing the …

Nitrate Ameliorates Alcohol-Induced Cognitive Impairment Via Oral Microbiota, Xiangxue Li, Zhaojun Ni, Weixiong Shi, Kangqing Zhao, Yanjie Zhang, Lina Liu, Zhong Wang, Jie Chen, Zhoulong Yu, Xuejiao Gao, Ying Qin, Jingwen Zhao, Wenjuan Peng, Jie Shi, Thomas R Kosten, Lin Lu, Lei Su, Yanxue Xue, Hongqiang Sun

Faculty, Staff and Students Publications

Alcohol use is associated with cognitive impairment and dysregulated inflammation. Oral nitrate may benefit cognitive impairment in aging through altering the oral microbiota. Similarly, the beneficial effects of nitrate on alcohol-induced cognitive decline and the roles of the oral microbiota merit investigation. Here we found that nitrate supplementation effectively mitigated cognitive impairment induced by chronic alcohol exposure in mice, reducing both systemic and neuroinflammation. Furthermore, nitrate restored the dysbiosis of the oral microbiota caused by alcohol consumption. Notably, removing the oral microbiota led to a subsequent loss of the beneficial effects of nitrate. Oral microbiota from donor alcohol use disordered …

Somatodendritic Orientation Determines Tdcs-Induced Neuromodulation Of Purkinje Cell Activity In Awake Mice, Carlos A Sánchez-León, Guillermo Sánchez-Garrido Campos, Marta Fernández, Álvaro Sánchez-López, Javier F Medina, Javier Márquez-Ruiz

Faculty, Staff and Students Publications

Transcranial direct-current stimulation (tDCS) of the cerebellum is a promising non-invasive neuromodulatory technique being proposed for the treatment of neurological and neuropsychiatric disorders. However, there is a lack of knowledge about how externally applied currents affect neuronal spiking activity in cerebellar circuits in vivo. We investigated how Cb-tDCS affects the firing rate of Purkinje cells (PC) and non-PC in the mouse cerebellar cortex to understand the underlying mechanisms behind the polarity-dependent modulation of neuronal activity induced by tDCS. Mice (n=9) were prepared for the chronic recording of local field potentials (LFPs) to assess the actual electric field gradient imposed by …

The Medial Olivocochlear Efferent Pathway Potentiates Cochlear Amplification In Response To Hearing Loss, Patricia M Quiñones, Michelle Pei, Hemant Srivastava, Ariadna Cobo-Cuan, Marcela A Morán, Bong Jik Kim, Clayton B Walker, Michael J Serafino, Frank Macias-Escriva, Juemei Wang, James B Dewey, Brian E Applegate, Matthew J Mcginley, John S Oghalai

Faculty, Staff and Students Publications

The mammalian cochlea receives efferent feedback from the brain. Many functions for this feedback have been hypothesized, including on short timescales, such as mediating attentional states, and long timescales, such as buffering acoustic trauma. Testing these hypotheses has been impeded by an inability to make direct measurements of efferent effects in awake animals. Here, we assessed the role of the medial olivocochlear (MOC) efferent nerve fibers on cochlear amplification by measuring organ of Corti vibratory responses to sound in both sexes of awake and anesthetized mice. We studied long-term effects by genetically ablating the efferents and/or afferents. Cochlear amplification increased …

An Unsupervised Map Of Excitatory Neuron Dendritic Morphology In The Mouse Visual Cortex, Marissa A Weis, Stelios Papadopoulos, Laura Hansel, Timo Lüddecke, Brendan Celii, Paul G Fahey, Eric Y Wang, J Alexander Bae, Agnes L Bodor, Derrick Brittain, Joann Buchanan, Daniel J Bumbarger, Manuel A Castro, Forrest Collman, Nuno Maçarico Da Costa, Sven Dorkenwald, Leila Elabbady, Akhilesh Halageri, Zhen Jia, Chris Jordan, Dan Kapner, Nico Kemnitz, Sam Kinn, Kisuk Lee, Kai Li, Ran Lu, Thomas Macrina, Gayathri Mahalingam, Eric Mitchell, Shanka Subhra Mondal, Shang Mu, Barak Nehoran, Sergiy Popovych, R Clay Reid, Casey M Schneider-Mizell, H Sebastian Seung, William Silversmith, Marc Takeno, Russel Torres, Nicholas L Turner, William Wong, Jingpeng Wu, Wenjing Yin, Szi-Chieh Yu, Jacob Reimer, Philipp Berens, Andreas S Tolias, Alexander S Ecker

Faculty, Staff and Students Publications

Neurons in the neocortex exhibit astonishing morphological diversity, which is critical for properly wiring neural circuits and giving neurons their functional properties. However, the organizational principles underlying this morphological diversity remain an open question. Here, we took a data-driven approach using graph-based machine learning methods to obtain a low-dimensional morphological "bar code" describing more than 30,000 excitatory neurons in mouse visual areas V1, AL, and RL that were reconstructed from the millimeter scale MICrONS serial-section electron microscopy volume. Contrary to previous classifications into discrete morphological types (m-types), our data-driven approach suggests that the morphological landscape of cortical excitatory neurons is …

Life On The Dry Side: A Roadmap To Understanding Desiccation Tolerance And Accelerating Translational Applications, R A Marks, J T B Ekwealor, M A S Artur, L Bondi, T C Boothby, O M S Carmo, D C Centeno, K K Coe, H J W Dace, S Field, A Hutt, S Porembski, A Thalhammer, L Van Der Pas, A J Wood, P Alpert, D Bartels, S Boeynaems, M N Datar, T Giese, W I Seidou, S M Kirchner, J Köhler, U G V S S Kumara, J Kyung, R Lyall, B D Mishler, J B V T Ndongmo, M S Otegui, V Reddy, J Rexroth, S M Tebele, R Vanburen, J Verdier, U C Vothknecht, M F Wittenberg, E Zokov, M J Oliver, S Y Rhee

Duncan NRI Faculty and Staff Publications

To thrive in extreme conditions, organisms have evolved a diverse arsenal of adaptations that confer resilience. These species, their traits, and the mechanisms underlying them comprise a valuable resource that can be mined for numerous conceptual insights and applied objectives. One of the most dramatic adaptations to water limitation is desiccation tolerance. Understanding the mechanisms underlying desiccation tolerance has important potential implications for medicine, biotechnology, agriculture, and conservation. However, progress has been hindered by a lack of standardization across sub-disciplines, complicating the integration of data and slowing the translation of basic discoveries into practical applications. Here, we synthesize current knowledge …

De Novo Variants In Cdkl1 And Cdkl2 Are Associated With Neurodevelopmental Symptoms, Ali H Bereshneh, Jonathan C Andrews, Daniel F Eberl, Guney Bademci, Nicholas A Borja, Stephanie Bivona, Wendy K Chung, Shinya Yamamoto, Michael F Wangler, Shane Mckee, Mustafa Tekin, Hugo J Bellen, Oguz Kanca

Duncan NRI Faculty and Staff Publications

The CDKL (cyclin-dependent kinase-like) family consists of five members in humans, CDKL1-5, that encode serine-threonine kinases. The only member that has been associated with a Mendelian disorder is CDKL5, and variants in CDKL5 cause developmental and epileptic encephalopathy type 2 (DEE2). Here, we study four de novo variants in CDKL2 identified in five individuals, including three unrelated probands and monozygotic twins. These individuals present with overlapping symptoms, including global developmental delay, intellectual disability, childhood-onset epilepsy, dyspraxia, and speech deficits. We also identified two individuals with de novo missense variants in CDKL1 in the published Deciphering Developmental Disorders (DDD) and GeneDx …

Glucose Uptake In Pigment Glia Suppresses Tau-Induced Inflammation And Photoreceptor Degeneration, Mikiko Oka, Sho Nakajima, Emiko Suzuki, Shinya Yamamoto, Kanae Ando

Duncan NRI Faculty and Staff Publications

Brain inflammation contributes to the pathogenesis of neurodegenerative diseases, such as Alzheimer's disease (AD). Glucose hypometabolism and glial activation are pathological features seen in AD brains; however, the connection between the two is not fully understood. Using a Drosophila model of AD, we identified that glucose metabolism in glia plays a critical role in neuroinflammation under disease conditions. Expression of human MATP (hereafter referred to as Tau) in the retinal cells, including photoreceptor neurons and pigment glia, causes photoreceptor degeneration accompanied by the formation of dark-stained round inclusion-like structures and swelling of the lamina cortex. We found that inclusion-like structures …

De Novo Variants In Rybp Are Associated With A Severe Neurodevelopmental Disorder And Congenital Anomalies, Monika Weisz-Hubshman, Lindsay C Burrage, Sharayu V Jangam, Jill A Rosenfeld, Sandra Von Hardenberg, Anke Bergmann, Manuela Friederike Richter, Malgorzata Rydzanicz, Rafal Ploski, Agnieszka Stembalska, Wendy K Chung, Rebecca R Hernan, Foong Y Lim, Theresa Brunet, Steffen Syrbe, Boris Keren, Solveig Heide, David R Murdock, Hongzheng Dai, Fan Xia, Shamika Ketkar, Brian Dawson, Vinodh Narayanan, Hillary K Graves, Undiagnosed Diseases Network, Michael F Wangler, Carlos Bacino, Brendan Lee

Duncan NRI Faculty and Staff Publications

Purpose: Polycomb group proteins are key epigenetic transcriptional regulators. Multiple neurodevelopmental disorders are associated with pathogenic variants of the genes encoding Polycomb group proteins. RYBP is a core component of the noncanonical Polycomb Repressor Complex 1; however, its role in disease is unclear.

Methods: Functional consequences of RYBP variants were assessed using in vitro cellular and in vivo Drosophila melanogaster studies.

Results: We described 7 individuals with heterozygous de novo variants of RYBP and their clinical findings, including severe developmental delay, dysmorphisms, and multiple congenital anomalies. We showed that all single-nucleotide variants in RYBP localize to the N-terminal domain of …

Neurd Offers Automated Proofreading And Feature Extraction For Connectomics, Brendan Celii, Stelios Papadopoulos, Zhuokun Ding, Paul G Fahey, Eric Wang, Christos Papadopoulos, Alexander B Kunin, Saumil Patel, J Alexander Bae, Agnes L Bodor, Derrick Brittain, Joann Buchanan, Daniel J Bumbarger, Manuel A Castro, Erick Cobos, Sven Dorkenwald, Leila Elabbady, Akhilesh Halageri, Zhen Jia, Chris Jordan, Dan Kapner, Nico Kemnitz, Sam Kinn, Kisuk Lee, Kai Li, Ran Lu, Thomas Macrina, Gayathri Mahalingam, Eric Mitchell, Shanka Subhra Mondal, Shang Mu, Barak Nehoran, Sergiy Popovych, Casey M Schneider-Mizell, William Silversmith, Marc Takeno, Russel Torres, Nicholas L Turner, William Wong, Jingpeng Wu, Szi-Chieh Yu, Wenjing Yin, Daniel Xenes, Lindsey M Kitchell, Patricia K Rivlin, Victoria A Rose, Caitlyn A Bishop, Brock Wester, Emmanouil Froudarakis, Edgar Y Walker, Fabian Sinz, H Sebastian Seung, Forrest Collman, Nuno Maçarico Da Costa, R Clay Reid, Xaq Pitkow, Andreas S Tolias, Jacob Reimer

Faculty, Staff and Students Publications

We are in the era of millimetre-scale electron microscopy volumes collected at nanometre resolution1,2. Dense reconstruction of cellular compartments in these electron microscopy volumes has been enabled by recent advances in machine learning3–6. Automated segmentation methods produce exceptionally accurate reconstructions of cells, but post hoc proofreading is still required to generate large connectomes that are free of merge and split errors. The elaborate 3D meshes of neurons in these volumes contain detailed morphological information at multiple scales, from the diameter, shape and branching patterns of axons and dendrites, down to the fine-scale …

Foundation Model Of Neural Activity Predicts Response To New Stimulus Types, Eric Y Wang, Paul G Fahey, Zhuokun Ding, Stelios Papadopoulos, Kayla Ponder, Marissa A Weis, Andersen Chang, Taliah Muhammad, Saumil Patel, Zhiwei Ding, Dat Tran, Jiakun Fu, Casey M Schneider-Mizell, Microns Consortium, R Clay Reid, Forrest Collman, Nuno Maçarico Da Costa, Katrin Franke, Alexander S Ecker, Jacob Reimer, Xaq Pitkow, Fabian H Sinz, Andreas S Tolias

Faculty, Staff and Students Publications

The complexity of neural circuits makes it challenging to decipher the brain’s algorithms of intelligence. Recent breakthroughs in deep learning have produced models that accurately simulate brain activity, enhancing our understanding of the brain’s computational objectives and neural coding. However, it is difficult for such models to generalize beyond their training distribution, limiting their utility. The emergence of foundation models1 trained on vast datasets has introduced a new artificial intelligence paradigm with remarkable generalization capabilities. Here we collected large amounts of neural activity from visual cortices of multiple mice and trained a foundation model to accurately predict neuronal responses …

Functional Connectomics Reveals General Wiring Rule In Mouse Visual Cortex, Zhuokun Ding, Paul G Fahey, Stelios Papadopoulos, Eric Y Wang, Brendan Celii, Christos Papadopoulos, Andersen Chang, Alexander B Kunin, Dat Tran, Jiakun Fu, Zhiwei Ding, Saumil Patel, Lydia Ntanavara, Rachel Froebe, Kayla Ponder, Taliah Muhammad, J Alexander Bae, Agnes L Bodor, Derrick Brittain, Joann Buchanan, Daniel J Bumbarger, Manuel A Castro, Erick Cobos, Sven Dorkenwald, Leila Elabbady, Akhilesh Halageri, Zhen Jia, Chris Jordan, Dan Kapner, Nico Kemnitz, Sam Kinn, Kisuk Lee, Kai Li, Ran Lu, Thomas Macrina, Gayathri Mahalingam, Eric Mitchell, Shanka Subhra Mondal, Shang Mu, Barak Nehoran, Sergiy Popovych, Casey M Schneider-Mizell, William Silversmith, Marc Takeno, Russel Torres, Nicholas L Turner, William Wong, Jingpeng Wu, Wenjing Yin, Szi-Chieh Yu, Dimitri Yatsenko, Emmanouil Froudarakis, Fabian Sinz, Krešimir Josić, Robert Rosenbaum, H Sebastian Seung, Forrest Collman, Nuno Maçarico Da Costa, R Clay Reid, Edgar Y Walker, Xaq Pitkow, Jacob Reimer, Andreas S Tolias

Faculty, Staff and Students Publications

Understanding the relationship between circuit connectivity and function is crucial for uncovering how the brain computes. In mouse primary visual cortex, excitatory neurons with similar response properties are more likely to be synaptically connected1–8; however, broader connectivity rules remain unknown. Here we leverage the millimetre-scale MICrONS dataset to analyse synaptic connectivity and functional properties of neurons across cortical layers and areas. Our results reveal that neurons with similar response properties are preferentially connected within and across layers and areas—including feedback connections—supporting the universality of ‘like-to-like’ connectivity across the visual hierarchy. Using a validated digital twin model, …

Inhibitory Specificity From A Connectomic Census Of Mouse Visual Cortex, Casey M Schneider-Mizell, Agnes L Bodor, Derrick Brittain, Joann Buchanan, Daniel J Bumbarger, Leila Elabbady, Clare Gamlin, Daniel Kapner, Sam Kinn, Gayathri Mahalingam, Sharmishtaa Seshamani, Shelby Suckow, Marc Takeno, Russel Torres, Wenjing Yin, Sven Dorkenwald, J Alexander Bae, Manuel A Castro, Akhilesh Halageri, Zhen Jia, Chris Jordan, Nico Kemnitz, Kisuk Lee, Kai Li, Ran Lu, Thomas Macrina, Eric Mitchell, Shanka Subhra Mondal, Shang Mu, Barak Nehoran, Sergiy Popovych, William Silversmith, Nicholas L Turner, William Wong, Jingpeng Wu, Jacob Reimer, Andreas S Tolias, H Sebastian Seung, R Clay Reid, Forrest Collman, Nuno Maçarico Da Costa

Faculty, Staff and Students Publications

Mammalian cortex features a vast diversity of neuronal cell types, each with characteristic anatomical, molecular and functional properties1. Synaptic connectivity shapes how each cell type participates in the cortical circuit, but mapping connectivity rules at the resolution of distinct cell types remains difficult. Here we used millimetre-scale volumetric electron microscopy2 to investigate the connectivity of all inhibitory neurons across a densely segmented neuronal population of 1,352 cells spanning all layers of mouse visual cortex, producing a wiring diagram of inhibition with more than 70,000 synapses. Inspired by classical neuroanatomy, we classified inhibitory neurons based on targeting of …

Alpha-Synuclein Phosphomimetic Y39e And S129d Knock-In Mice Show Cytosolic Alpha-Synuclein Localization Without Developing Neurodegeneration Or Motor Deficits, Youngdoo Kim, Bhupesh Vaidya, Joseph Mcinnes, Huda Y Zoghbi

Duncan NRI Faculty and Staff Publications

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by motor and nonmotor symptoms. Its pathological hallmarks include the accumulation of misfolded alpha-synuclein (α-Syn) in Lewy bodies and Lewy neurites. Phosphorylation of α-Syn is a prominent feature of these inclusions, but its role in disease pathogenesis remains unclear. To identify the role of α-Syn phosphorylation in synucleinopathy, we generated two Snca knock-in (KI) mouse models carrying phosphomimetic mutations at SncaY39 or SncaS129 (Snca^Y39E or Snca^S129D) which manipulated epitopes phosphorylated in the PD brain. Both Snca^Y39E and Snca^S129D KI mice displayed increased α-Syn phosphorylation, enhanced …

Foraging Animals Use Dynamic Bayesian Updating To Model Meta-Uncertainty In Environment Representations, James Webb, Paul Steffan, Benjamin Y Hayden, Daeyeol Lee, Caleb Kemere, Matthew Mcginley

Faculty, Staff and Students Publications

Foraging theory predicts animal behavior in many contexts. In patch-based foraging behaviors, the marginal value theorem (MVT) gives the optimal strategy for deterministic environments whose parameters are fully known to the forager. In natural settings, environmental parameters exhibit variability and are only partially known to the animal based on its experience, creating uncertainty. Models of uncertainty in foraging are well established. However, natural environments also exhibit unpredicted changes in their statistics. As a result, animals must ascertain whether the currently observed quality of the environment is consistent with their internal models, or whether something has changed, creating meta-uncertainty. Behavioral strategies …

Distinct Patterns Of Pv And Sst Gabaergic Neuronal Activity In The Basal Forebrain During Olfactory-Guided Behavior In Mice, Elizabeth H Moss, Evelyne K Tantry, Elaine Le, Pey-Shyuan Chin, Priscilla Ambrosi, Katie L Brandel-Ankrapp, Benjamin R Arenkiel

Duncan NRI Faculty and Staff Publications

Sensory perception relies on the flexible detection and interpretation of stimuli across variable contexts, conditions, and behavioral states. The basal forebrain (BF) 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 BF, parvalbumin (PV) and somatostatin (SST) subtypes serve opposing roles toward regulating behavioral states. To elucidate the role of BF circuits in sensory-guided behavior, we investigated GABAergic signaling dynamics during odor-guided decision-making in male and female mice. We used fiber photometry to record cell type-specific BF activity during an odor discrimination task …

Multi-Omics Delineate Growth Factor Network Underlying Exercise Effects In An Alzheimer’S Mouse Model, Xin Li, Chaozhong Liu, Wenbo Li, Guantong Qi, Yanwan Dai, Chaohao Gu, Yuxiang Sun, Wenjun Zhou, Veronica C Ciliberto, Jing Liang, Udhaya Kumar S, Dongyin Guan, Zhaoyong Hu, Hui Zheng, Zhandong Liu, Hu Chen, Ying-Wooi Wan, Zheng Sun

Duncan NRI Faculty and Staff Publications

Introduction: Physical exercise is a primary defense against age-related cognitive decline and Alzheimer's disease (AD).

Methods: We conducted single-nucleus transcriptomic and chromatin accessibility analyses (snRNA-seq and snATAC-seq) on the hippocampus of mice carrying mutations in the amyloid precursor protein gene (APPNL-G-F) following prolonged voluntary wheel-running exercise.

Results: Exercise mitigates amyloid-induced changes in transcriptome and chromatin accessibility through cell type-specific regulatory networks converging on growth factor signaling, particularly the epidermal growth factor receptor (EGFR) signaling. The beneficial effects of exercise on neurocognition can be blocked by pharmacological inhibition of EGFR and its downstream PI3K signaling. Exercise leads to elevated levels of …

Visible Light Polarization-Sensitive Optical Coherence Tomography With Balanced Detection, Bahar Baradaran, Adam J Black, Sarah R Heilbronner, Taner Akkin

Faculty, Staff and Students Publications

Significance: We introduce a visible-light polarization-sensitive optical coherence tomography (PS-OCT) system that operates in the spectral domain with balanced detection (BD) capability. While the BD improves the signal-to-noise ratio (SNR), the use of shorter wavelengths improves spatial resolution and birefringence sensitivity.

Aim: We aim to implement a new optical design, characterize its performance, and investigate the imaging potential for biological tissues.

Approach: The design utilizes a unique interferometer and a custom spectrometer that captures four highly aligned spectra with a single area/multi-line camera. Each pair of spectral lines is highly aligned, and their subtraction yields balanced detected spectra of the …

Thalamic Deep Brain Stimulation Improves Movement In A Cerebellar Model Of Lesion-Based Status Dystonicus, Megan X Nguyen, Amanda M Brown, Tao Lin, Roy V Sillitoe, Jason S Gill

Faculty, Staff and Students Publications

Dystonia is the third most common movement disorder and an incapacitating co-morbidity in a variety of neurologic conditions. Dystonia can be caused by genetic, degenerative, idiopathic, and acquired etiologies, which are hypothesized to converge on a "dystonia network" consisting of the basal ganglia, thalamus, cerebellum, and cerebral cortex. In acquired dystonia, focal lesions to subcortical network regions lead to dystonia that can be difficult to manage with canonical treatments, including deep brain stimulation (DBS). While studies in animal models have begun to parse the contribution of individual nodes in the dystonia network, how acquired injury to the cerebellar outflow tracts …

Inhibition Of Il-6 Trans-Signaling Promotes Post-Stroke Functional Recovery In A Sex And Dose-Dependent Manner, Cassandra Hall, Dustin T Nguyen, Kate Mendoza, Chunfeng Tan, Anjali Chauhan

Faculty, Staff and Student Publications

Introduction: Elevated circulating IL-6 levels are associated with poorer outcomes after stroke, and increased serum IL-6 levels are linked to a higher risk of stroke. IL-6 binds to soluble IL-6 receptors (sIL-6R) and subsequently to ubiquitously expressed gp130, initiating proinflammatory trans-signaling. This study tested the hypothesis that inhibiting IL-6 trans-signaling by administering soluble (s) gp130 improves long-term functional outcomes in young mice after stroke.

Methods: Recombinant mouse gp130Fc chimera (sgp130) was administered one hour after middle cerebral artery occlusion (MCAO) followed by twice-weekly administration for 2 weeks in mice (8-15 weeks old). Behavioral assessments were done on days 7 and …

Single-Cell Analysis Identifies Ifi27l2a As A Gene Regulator Of Microglial Inflammation In The Context Of Aging And Stroke In Mice, Gab Seok Kim, Elisabeth Harmon, Manuel C Gutierrez, Sodam Kim, Lauren Vance, Haven Burrous, Jessica M Stephenson, Anjali Chauhan, Anik Banerjee, Zachary Wise, Andrea Doan, John Ahn, Ting Wu, Jesus Bautista-Garrido, Juneyoung Lee, Chunfeng Tan, Joo Eun Jung, Louise D Mccullough, Joshua D Wythe, Sean P Marrelli

Faculty, Staff and Student Publications

Inflammation is a significant driver of ischemic stroke pathology in the brain. To identify potential regulators of inflammation, we performed single-cell RNA sequencing (scRNA-seq) of young and aged mouse brains following stroke and found that interferon alpha-inducible protein 27 like 2 A (Ifi27l2a) was significantly up-regulated, particularly in microglia of aged brain. Ifi27l2a is induced by interferons for viral host defense and has been linked with pro-inflammatory cellular mechanisms. However, its potential role in neurodegeneration is unknown. Using a combination of cell culture, experimental stroke models in mice, and human autopsy brain samples, we demonstrated that induction of Ifi27l2a occurs …

Neuronal Network Activation Induced By Forniceal Deep Brain Stimulation In Mice, Bin Tang, Zhenyu Wu, Qi Wang, Jianrong Tang

Faculty, Staff and Students Publications

Background: The fimbria-fornix is a nerve fiber bundle that connects various structures of the limbic system in the brain and plays a key role in cognition. It has become a major target of deep brain stimulation (DBS) to treat memory impairment in both dementia patients and animal models of neurological diseases. Previously, we have reported the beneficial memory effects of chronic forniceal DBS in mouse models of intellectual disability disorders. In Rett syndrome and CDKL5 deficiency disorder models, DBS strengthens hippocampal synaptic plasticity, reduces dentate inhibitory transmission or increases adult hippocampal neurogenesis that aids memory. However, the underlying neuronal circuitry …

Motor Pool Selectivity Of Neuromuscular Degeneration In Type I Spinal Muscular Atrophy Is Conserved Between Human And Mouse, Justin C Lee, Wendy K Chung, David J Pisapia, Christopher E Henderson

Faculty, Staff and Students Publications

Spinal muscular atrophy (SMA) is caused by low levels of the survival motor neuron (SMN) protein. Even though SMN is ubiquitously expressed, the disease selectively affects motor neurons, leading to progressive muscle weakness. Even among motor neurons, certain motor units appear more clinically resistant to SMA. To quantitatively survey selective resistance, we studied extensive neuromuscular autopsies of Type I SMA patients and age-matched controls. We found highly divergent degrees of degeneration of neighboring motor units, even within individual cranial nerves or a single anatomical area such as the neck. Examination of a Type I SMA patient maintained on life support …

Targeting Tiam1 Enhances Hippocampal-Dependent Learning And Memory In The Adult Brain And Promotes Nmda Receptor-Mediated Synaptic Plasticity And Function, Francisco A Blanco, Md Ali Bin Saifullah, Jinxuan X Cheng, Carlota Abella, Federico Scala, Karen Firozi, Sanyong Niu, Jin Park, Jeannie Chin, Kimberley F Tolias

Faculty, Staff and Students Publications

Excitatory synapses and the actin-rich dendritic spines on which they reside are indispensable for information processing and storage in the brain. In the adult hippocampus, excitatory synapses must balance plasticity and stability to support learning and memory. However, the mechanisms governing this balance remain poorly understood. Tiam1 is an actin cytoskeleton regulator prominently expressed in the dentate gyrus (DG) throughout life. Previously, we showed that Tiam1 promotes dentate granule cell synapse and spine stabilization during development, but its role in the adult hippocampus remains unclear. Here, we deleted Tiam1 from adult forebrain excitatory neurons (Tiam1^fKO) and assessed …

From Bench To Bedside: Murine Models Of Inherited And Sporadic Brain Arteriovenous Malformations, Ashely R Ricciardelli, Gael Genet, Nafiisha Genet, Samuel T Mcclugage, Peter T Kan, Karen K Hirschi, Jason E Fish, Joshua D Wythe

Faculty, Staff and Students Publications

Brain arteriovenous malformations are abnormal vascular structures in which an artery shunts high pressure blood directly to a vein without an intervening capillary bed. These lesions become highly remodeled over time and are prone to rupture. Historically, brain arteriovenous malformations have been challenging to treat, using primarily surgical approaches. Over the past few decades, the genetic causes of these malformations have been uncovered. These can be divided into (1) familial forms, such as loss of function mutations in TGF-β (BMP9/10) components in hereditary hemorrhagic telangiectasia, or (2) sporadic forms, resulting from somatic gain of function mutations in genes involved in …

Investigating The In Vivo Effects Of Anti-Prion Protein Nanobodies On Prion Disease With Aav Vector, Jingjing Zhang, Mengfei Wang, Dan Wang, Xiangyi Zhang, Yue Ma, Els Pardon, Jan Steyaert, Romany Abskharon, Fei Wang, Jiyan Ma

Faculty, Staff and Student Publications

Prion diseases are fatal neurodegenerative disorders affecting humans and animals, and the central pathogenic event is the conversion of normal prion protein (PrPC) into the pathogenic PrPSc isoform. Previous studies have identified nanobodies that specifically recognize PrPC and inhibit the PrPC to PrPSc conversion in vitro. In this study, we investigated the potential for in vivo expression of anti-PrPC nanobodies and evaluated their impact on prion disease. The coding sequences of three nanobodies were packaged into recombinant adeno-associated virus (rAAV) and were administered via intracerebroventricular (ICV) injection in newborn mice. We found that the expression of these nanobodies remained robust …

Protein Arginine Methyltransferases As Regulators Of Cellular Stress, Julia Zaccarelli-Magalhães, Cristiane Teresinha Citadin, Julia Langman, Drew James Smith, Luiz Henrique Matuguma, Hung Wen Lin, Mariana Sayuri Berto Udo

Faculty, Staff and Student Publications

Arginine modification can be a "switch" to regulate DNA transcription and a post-translational modification via methylation of a variety of cellular targets involved in signal transduction, gene transcription, DNA repair, and mRNA alterations. This consequently can turn downstream biological effectors "on" and "off". Arginine methylation is catalyzed by protein arginine methyltransferases (PRMTs 1-9) in both the nucleus and cytoplasm, and is thought to be involved in many disease processes. However, PRMTs have not been well-documented in the brain and their function as it relates to metabolism, circulation, functional learning and memory are understudied. In this review, we provide a comprehensive …

Synaptic Alterations In Pyramidal Cells Following Genetic Manipulation Of Neuronal Excitability In Monkey Prefrontal Cortex, Guillermo Gonzalez-Burgos, Takeaki Miyamae, Yosuke Nishihata, Olga L Krimer, Kirsten Wade, Kenneth N Fish, Dominique Arion, Zhao-Lin Cai, Mingshan Xue, William R Stauffer, David A Lewis

Duncan NRI Faculty and Staff Publications

The primate dorsolateral prefrontal cortex (DLPFC) displays unique in vivo activity patterns, but how in vivo activity regulates DLPFC pyramidal neuron (PN) properties remains unclear. We assessed the effects of in vivo Kir2.1 overexpression, a genetic silencing tool, on synapses in monkey DLPFC PNs. We show for the first time that recombinant ion channel expression successfully modifies the excitability of primate cortex neurons, producing effects on synaptic properties apparently different from those in the rodent cortex.

Magnesium Sulfate In The Management Of Acute Ischemic Stroke: A Review Of The Literature And Future Directions, Maximillian S Feygin, Alex Brenner, Omar Tanweer

Faculty, Staff and Students Publications

Background: The management of acute ischemic stroke (AIS) was revolutionized within the last 15 years with the introduction of mechanical thrombectomy (MT) to standard of care. Despite the success of mechanical thrombectomy (MT) in achieving high recanalization rates for large vessel occlusion, functional independence post-treatment remains suboptimal. The current limitations of MT prompt evaluation of the role of adjunctive pharmacologic neuroprotective therapies to prevent excitotoxicity, cellular apoptosis, and inflammation that cause irreversible neuronal damage during AIS. Magnesium (MgSO4) provides an attractive neuroprotectant profile, having many different effects, and is inexpensive, readily available, and has a long-established safety and tolerability profile …

High Cellular Plasticity State Of Medulloblastoma Local Recurrence And Distant Dissemination, Hailong Liu, Jing Zhang, Ziwei Wang, Wei Wang, Dongming Han, Xuan Chen, Yu Su, Jiao Zhang, Craig Daniels, Olivier Saulnier, Zeyuan John Wang, Chunyu Gu, Fei Liu, Kaiwen Deng, Dongyang Wang, Zhaoyang Feng, Yahui Zhao, Yifei Jiang, Yu Gao, Zijia Liu, Mingxu Ma, Yanong Li, Zitong Zhao, Hongyu Yuan, Youliang Sun, Yanfeng Shi, Tao Yang, Wenxing Li, Xueling Qi, Zejun Duan, Junping Zhang, Mingshan Zhang, Chunjiang Yu, Wei Jin, Xinguang Yu, Yu Tian, Shuaicheng Li, Chunde Li, Michael D Taylor, Jiankang Li, Yong-Qiang Liu, Xiaoguang Qiu, Tao Jiang

Faculty, Staff and Students Publications

Medulloblastoma (MB), a heterogeneous pediatric brain tumor, poses challenges in the treatment of tumor recurrence and dissemination. To characterize cellular diversity and genetic features, we comprehensively analyzed single-cell/nucleus RNA sequencing (sc/snRNA-seq), single-nucleus assay for transposase-accessible chromatin sequencing (snATAC-seq), and spatial transcriptomics profiles and identified distinct cellular populations in SHH (sonic hedgehog) and Group_3 subgroups, with varying proportions in local recurrence or dissemination. Local recurrence showed higher cycling tumor cell enrichment, whereas disseminated lesions had a relatively notable presence of differentiated subsets. Chromosomal alteration evaluation revealed distinct genetic subclones during MB progression, such as chr7q gain and chr11 loss in Group_3 …