Neurology Commons^™

Circuit-Specific Deep Brain Stimulation Provides Insights Into Movement Control., Aryn H Gittis, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

Deep brain stimulation (DBS), a method in which electrical stimulation is delivered to specific areas of the brain, is an effective treatment for managing symptoms of a number of neurological and neuropsychiatric disorders. Clinical access to neural circuits during DBS provides an opportunity to study the functional link between neural circuits and behavior. This review discusses how the use of DBS in Parkinson's disease and dystonia has provided insights into the brain networks and physiological mechanisms that underlie motor control. In parallel, insights from basic science about how patterns of electrical stimulation impact plasticity and communication within neural circuits are …

Cerebellar Nuclei Cells Produce Distinct Pathogenic Spike Signatures In Mouse Models Of Ataxia, Dystonia, And Tremor, Meike E Van Der Heijden, Amanda M Brown, Dominic J Kizek, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

The cerebellum contributes to a diverse array of motor conditions, including ataxia, dystonia, and tremor. The neural substrates that encode this diversity are unclear. Here, we tested whether the neural spike activity of cerebellar output neurons is distinct between movement disorders with different impairments, generalizable across movement disorders with similar impairments, and capable of causing distinct movement impairments. Using in vivo awake recordings as input data, we trained a supervised classifier model to differentiate the spike parameters between mouse models for ataxia, dystonia, and tremor. The classifier model correctly assigned mouse phenotypes based on single-neuron signatures. Spike signatures were shared …

Ragopathies And The Rising Influence Of Raggtpases On Human Diseases, Irene Sambri, Marco Ferniani, Andrea Ballabio

Duncan NRI Faculty and Staff Publications

RagGTPases (Rags) play an essential role in the regulation of cell metabolism by controlling the activities of both mechanistic target of rapamycin complex 1 (mTORC1) and Transcription factor EB (TFEB). Several diseases, herein named ragopathies, are associated to Rags dysfunction. These diseases may be caused by mutations either in genes encoding the Rags, or in their upstream regulators. The resulting phenotypes may encompass a variety of clinical features such as cataract, kidney tubulopathy, dilated cardiomyopathy and several types of cancer. In this review, we focus on the key clinical, molecular and physio-pathological features of ragopathies, aiming to shed light on …

Tiam1-Mediated Maladaptive Plasticity Underlying Morphine Tolerance And Hyperalgesia, Changqun Yao, Xing Fang, Qin Ru, Wei Li, Jun Li, Zeinab Mehsein, Kimberley F Tolias, Lingyong Li

Faculty, Staff and Students Publications

Opioid pain medications, such as morphine, remain the mainstay for treating severe and chronic pain. Prolonged morphine use, however, triggers analgesic tolerance and hyperalgesia (OIH), which can last for a long period after morphine withdrawal. How morphine induces these detrimental side effects remains unclear. Here, we show that morphine tolerance and OIH are mediated by Tiam1-coordinated synaptic structural and functional plasticity in the spinal nociceptive network. Tiam1 is a Rac1 GTPase guanine nucleotide exchange factor that promotes excitatory synaptogenesis by modulating actin cytoskeletal dynamics. We found that prolonged morphine treatment activated Tiam1 in the spinal dorsal horn and Tiam1 ablation …

What’S The N? On Sample Size Vs. Subject Number For Brain-Behavior Neurophysiology And Neuromodulation, Wael F Asaad, Sameer A Sheth

Duncan NRI Faculty and Staff Publications

Neurophysiology and neuromodulation strive to understand the neural basis of behavior through a one-to-one correspondence between a particular brain and its behavioral output. Within this framework, studies with few subjects but sufficient sample sizes can be both rigorous and impactful.

Clinicopathologic Dissociation: Robust Lafora Body Accumulation In Malin Ko Mice Without Observable Changes In Home-Cage Behavior, Vaishnav Krishnan, Jun Wu, Arindam Ghosh Mazumder, Jessica L Kamen, Catharina Schirmer, Nandani Adhyapak, John Samuel Bass, Samuel C Lee, Atul Maheshwari, Gemma Molinaro, Jay R Gibson, Kimberly M Huber, Berge A Minassian

Faculty, Staff and Students Publications

Lafora disease (LD) is a syndrome of progressive myoclonic epilepsy and cumulative neurocognitive deterioration caused by recessively inherited genetic lesions of EPM2A (laforin) or NHLRC1 (malin). Neuropsychiatric symptomatology in LD is thought to be directly downstream of neuronal and astrocytic polyglucosan aggregates, termed Lafora bodies (LBs), which faithfully accumulate in an age-dependent manner in all mouse models of LD. In this study, we applied home-cage monitoring to examine the extent of neurobehavioral deterioration in a model of malin-deficient LD as a means to identify robust preclinical endpoints that may guide the selection of novel genetic treatments. At 6 weeks, ∼6-7 …

Protocol For Preclinical Evaluation Of Locoregionally Delivered Car T Cells In Patient-Derived Xenograft Models Of Brain Tumors, Benjamin Draper, Chantelle Bowers, Eleni Vassalou, Ailsa Greppi, John Anderson, Nabil Ahmed, Michael D Taylor, Laura K Donovan

Faculty, Staff and Students Publications

Here, we present a protocol for preclinical evaluation of locoregionally delivered CAR T cells in patient-derived xenograft models of primary, metastatic, and recurrent brain tumors. We provide instructions for isolating peripheral blood mononuclear cells (PBMCs), producing CAR T cells in conjunction with locoregional delivery, and preclinical trial design and analysis involving CAR T cells. Additionally, we describe comprehensive preclinical readouts and guidelines for critical endpoint sample collections. In line with clinical trial procedures, our protocol broadens available treatment modalities for direct clinical translation. For complete details on the use and execution of this protocol, please refer to Donovan et al …

Fate-Mapping And Functional Dissection Reveal Perilous Influence Of Type I Interferon Signaling In Mouse Brain Aging, Ethan R Roy, Sanming Li, Sepideh Saroukhani, Yanyu Wang, Wei Cao

Faculty, Staff and Student Publications

Background: Aging significantly elevates the risk of developing neurodegenerative diseases. Neuroinflammation is a universal hallmark of neurodegeneration as well as normal brain aging. Which branches of age-related neuroinflammation, and how they precondition the brain toward pathological progression, remain ill-understood. The presence of elevated type I interferon (IFN-I) has been documented in the aged brain, but its role in promoting degenerative processes, such as the loss of neurons in vulnerable regions, has not been studied in depth.

Methods: To comprehend the scope of IFN-I activity in the aging brain, we surveyed IFN-I-responsive reporter mice at multiple ages. We also examined 5- …

Hemojuvelin-Mediated Hepcidin Induction Requires Both Bone Morphogenetic Protein Type I Receptors Alk2 And Alk3, Deniz Y Dogan, Eugen I Urzica, Isabelle Hornung, Philipp Kastl, David Oguama, Franca M Fette, Lien H Nguyen, Frank Rosenbauer, Kai Zacharowski, Ursula Klingmüller, Elise Gradhand, Andreas Von Knethen, Rüdiger Popp, Ingrid Fleming, Lisa Schrader, Andrea U Steinbicker

Faculty, Staff and Student Publications

Hemojuvelin (HJV) is a glycosylphosphatidylinositol-anchored protein of the repulsive guidance molecule family acting as a bone morphogenetic protein (BMP) coreceptor to induce the hepatic iron regulatory protein hepcidin. Hepcidin causes ubiquitination and degradation of the sole known iron exporter ferroportin, thereby limiting iron availability. The detailed signaling mechanism of HJV in vivo has yet to be investigated. In the current manuscript, we used an established model of adeno-associated virus (AAV)-mediated liver-specific overexpression of HJV in murine models of hepatocyte-specific deficiency of the BMP type I receptors Alk2 or Alk3. In control mice, HJV overexpression increased hepatic Hamp messenger RNA (mRNA) …

Perturbations In Risk/Reward Decision Making And Frontal Cortical Catecholamine Regulation Induced By Mild Traumatic Brain Injury, Christopher P Knapp, Eleni Papadopoulos, Jessica A Loweth, Ramesh Raghupathi, Stan B Floresco, Barry D Waterhouse, Rachel L Navarra

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Mild traumatic brain injury (mTBI) disrupts cognitive processes that influence risk taking behavior. Little is known regarding the effects of repetitive mild injury (rmTBI) or whether these outcomes are sex specific. Risk/reward decision making is mediated by the prefrontal cortex (PFC), which is densely innervated by catecholaminergic fibers. Aberrant PFC catecholamine activity has been documented following TBI and may underlie TBI-induced risky behavior. The present study characterized the effects of rmTBI on risk/reward decision making behavior and catecholamine transmitter regulatory proteins within the PFC. Rats were exposed to sham, single (smTBI), or three closed-head controlled cortical impact (CH-CCI) injuries and …

Purkinje Cell Dysfunction Causes Disrupted Sleep In Ataxic Mice, Luis E Salazar Leon, Amanda M Brown, Heet Kaku, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

Purkinje cell dysfunction disrupts movement and causes disorders such as ataxia. Recent evidence suggests that Purkinje cell dysfunction may also alter sleep regulation. Here, we used an ataxic mouse model generated by silencing Purkinje cell neurotransmission (L7Cre;Vgatfx/fx) to better understand how cerebellar dysfunction impacts sleep physiology. We focused our analysis on sleep architecture and electrocorticography (ECoG) patterns based on their relevance to extracting physiological measurements during sleep. We found that circadian activity was unaltered in the mutant mice, although their sleep parameters and ECoG patterns were modified. The L7Cre;Vgatfx/fx mutant mice had decreased wakefulness and rapid eye movement (REM) sleep, …

Presynaptic Nanoscale Components Of Retrograde Synaptic Signaling, Benjámin Barti, Barna Dudok, Kata Kenesei, Miklós Zöldi, Vivien Miczán, Gyula Y Balla, Diana Zala, Mariana Tasso, Claudia Sagheddu, Máté Kisfali, Blanka Tóth, Marco Ledri, E Sylvester Vizi, Miriam Melis, László Barna, Zsolt Lenkei, Iván Soltész, István Katona

Faculty, Staff and Students Publications

While our understanding of the nanoscale architecture of anterograde synaptic transmission is rapidly expanding, the qualitative and quantitative molecular principles underlying distinct mechanisms of retrograde synaptic communication remain elusive. We show that a particular form of tonic cannabinoid signaling is essential for setting target cell–dependent synaptic variability. It does not require the activity of the two major endocannabinoid-producing enzymes. Instead, by developing a workflow for physiological, anatomical, and molecular measurements at the same unitary synapse, we demonstrate that the nanoscale stoichiometric ratio of type 1 cannabinoid receptors (CB1Rs) to the release machinery is sufficient to predict synapse-specific release probability. Accordingly, …

Glioblastoma Disrupts Cortical Network Activity At Multiple Spatial And Temporal Scales, Jochen Meyer, Kwanha Yu, Estefania Luna-Figueroa, Benjamin Deneen, Jeffrey Noebels

Faculty, Staff and Students Publications

The emergence of glioblastoma in cortical tissue initiates early and persistent neural hyperexcitability with signs ranging from mild cognitive impairment to convulsive seizures. The influence of peritumoral synaptic density, expansion dynamics, and spatial contours of excess glutamate upon higher order neuronal network modularity is unknown. We combined cellular and widefield imaging of calcium and glutamate fluorescent reporters in two glioblastoma mouse models with distinct synaptic microenvironments and infiltration profiles. Functional metrics of neural ensembles are dysregulated during tumor invasion depending on the stage of malignant progression and tumor cell proximity. Neural activity is differentially modulated during periods of accelerated and …

Astrocytes Remember Inflammation, Michael R Williamson, Benjamin Deneen

Faculty, Staff and Students Publications

Astrocytes respond to all forms of central nervous system maladies. In a recent issue of Nature, Lee et al. demonstrate that astrocytes encode inflammatory stimuli as epigenetic memory, which strengthens responses to subsequent stimuli and exacerbates pathology in disease models.

Modulation Of The Blood-Brain Barrier By Sigma-1r Activation, Eugen Brailoiu, Jeffrey L Barr, Hailey N Wittorf, Saadet Inan, Ellen M Unterwald, Gabriela Cristina Brailoiu

Faculty, Staff and Student Publications

Sigma non-opioid intracellular receptor 1 (Sigma-1R) is an intracellular chaperone protein residing on the endoplasmic reticulum at the mitochondrial-associated membrane (MAM) region. Sigma-1R is abundant in the brain and is involved in several physiological processes as well as in various disease states. The role of Sigma-1R at the blood-brain barrier (BBB) is incompletely characterized. In this study, the effect of Sigma-1R activation was investigated in vitro on rat brain microvascular endothelial cells (RBMVEC), an important component of the blood-brain barrier (BBB), and in vivo on BBB permeability in rats. The Sigma-1R agonist PRE-084 produced a dose-dependent increase in mitochondrial calcium, …

Autologous Bone Marrow Mononuclear Cells To Treat Severe Traumatic Brain Injury In Children, Charles S Cox, David M Notrica, Jenifer Juranek, Jeffrey H Miller, Fabio Triolo, Steven Kosmach, Sean I Savitz, P David Adelson, Claudia Pedroza, Scott D Olson, Michael C Scott, Akshita Kumar, Benjamin M Aertker, Henry W Caplan, Margaret L Jackson, Brijesh S Gill, Robert A Hetz, Michael S Lavoie, Linda Ewing-Cobbs

Faculty, Staff and Student Publications

Autologous bone marrow mononuclear cells (BMMNCs) infused after severe traumatic brain injury have shown promise for treating the injury. We evaluated their impact in children, particularly their hypothesized ability to preserve the blood–brain barrier and diminish neuroinflammation, leading to structural CNS preservation with improved outcomes.

We performed a randomized, double-blind, placebo-sham-controlled Bayesian dose-escalation clinical trial at two children's hospitals in Houston, TX and Phoenix, AZ, USA (NCT01851083). Patients 5–17 years of age with severe traumatic brain injury (Glasgow Coma Scale score ≤ 8) were randomized to BMMNC or placebo (3:2). Bone marrow harvest, cell isolation and infusion were …

Piezo1 Regulates Meningeal Lymphatic Vessel Drainage And Alleviates Excessive Csf Accumulation, Dongwon Choi, Eunkyung Park, Joshua Choi, Renhao Lu, Jin Suh Yu, Chiyoon Kim, Luping Zhao, James Yu, Brandon Nakashima, Sunju Lee, Dhruv Singhal, Joshua P Scallan, Bin Zhou, Chester J Koh, Esak Lee, Young-Kwon Hong

Faculty, Staff and Students Publications

Piezo1 regulates multiple aspects of the vascular system by converting mechanical signals generated by fluid flow into biological processes. Here, we find that Piezo1 is necessary for the proper development and function of meningeal lymphatic vessels and that activating Piezo1 through transgenic overexpression or treatment with the chemical agonist Yoda1 is sufficient to increase cerebrospinal fluid (CSF) outflow by improving lymphatic absorption and transport. The abnormal accumulation of CSF, which often leads to hydrocephalus and ventriculomegaly, currently lacks effective treatments. We discovered that meningeal lymphatics in mouse models of Down syndrome were incompletely developed and abnormally formed. Selective overexpression of …

Interaction Of High-Fat Diet And Brain Trauma Alters Adipose Tissue Macrophages And Brain Microglia Associated With Exacerbated Cognitive Dysfunction, Rebecca J Henry, James P Barrett, Maria Vaida, Niaz Z Khan, Oleg Makarevich, Rodney M Ritzel, Alan I Faden, Bogdan A Stoica

Faculty, Staff and Student Publications

Obesity increases the morbidity and mortality of traumatic brain injury (TBI). Detailed analyses of transcriptomic changes in the brain and adipose tissue were performed to elucidate the interactive effects between high-fat diet-induced obesity (DIO) and TBI. Adult male mice were fed a high-fat diet (HFD) for 12 weeks prior to experimental TBI and continuing after injury. High-throughput transcriptomic analysis using Nanostring panels of the total visceral adipose tissue (VAT) and cellular components in the brain, followed by unsupervised clustering, principal component analysis, and IPA pathway analysis were used to determine shifts in gene expression patterns and molecular pathway activity. Cellular …

Linear And Nonlinear Behaviors Of The Photoreceptor Coupled Network, Ji-Jie Pang, Xiaolong Jiang, Samuel M Wu

Faculty, Staff and Students Publications

Photoreceptors are electrically coupled to one another, and the spatiotemporal properties of electrical synapses in a two-dimensional retinal network are still not well studied, because of the limitation of the single electrode or pair recording techniques which do not allow simultaneously measuring responses of multiple photoreceptors at various locations in the retina. A multiple electrode recording system is needed. In this study, we investigate the network properties of the two-dimensional rod coupled array of the salamander retina (both sexes were used) by using the newly available multiple patch electrode system that allows simultaneous recordings from up to eight cells and …

Miniature Battery-Free Epidural Cortical Stimulators, Joshua E Woods, Amanda L Singer, Fatima Alrashdan, Wendy Tan, Chunfeng Tan, Sunil A Sheth, Sameer A Sheth, Jacob T Robinson

Faculty, Staff and Student Publications

Miniaturized neuromodulation systems could improve the safety and reduce the invasiveness of bioelectronic neuromodulation. However, as implantable bioelectronic devices are made smaller, it becomes difficult to store enough power for long-term operation in batteries. Here, we present a battery-free epidural cortical stimulator that is only 9 millimeters in width yet can safely receive enough wireless power using magnetoelectric antennas to deliver 14.5-volt stimulation bursts, which enables it to stimulate cortical activity on-demand through the dura. The device has digitally programmable stimulation output and centimeter-scale alignment tolerances when powered by an external transmitter. We demonstrate that this device has enough power …

Bi-Directional Neuro-Immune Dysfunction After Chronic Experimental Brain Injury, Rodney M Ritzel, Yun Li, Yun Jiao, Sarah J Doran, Niaz Khan, Rebecca J Henry, Kavitha Brunner, David J Loane, Alan I Faden, Gregory L Szeto, Junfang Wu

Faculty, Staff and Student Publications

Background

It is well established that traumatic brain injury (TBI) causes acute and chronic alterations in systemic immune function and that systemic immune changes contribute to posttraumatic neuroinflammation and neurodegeneration. However, how TBI affects bone marrow (BM) hematopoietic stem/progenitor cells chronically and to what extent such changes may negatively impact innate immunity and neurological function has not been examined.

Methods

To further understand the role of BM cell derivatives on TBI outcome, we generated BM chimeric mice by transplanting BM from chronically injured or sham (i.e., 90 days post-surgery) congenic donor mice into otherwise healthy, age-matched, irradiated CD45.2 C57BL/6 (WT) …

Gabaergic/Glycinergic And Glutamatergic Neurons Mediate Distinct Neurodevelopmental Phenotypes Of Stxbp1 Encephalopathy, Joo Hyun Kim, Wu Chen, Eugene S Chao, Armando Rivera, Heet Naresh Kaku, Kevin Jiang, Dongwon Lee, Hongmei Chen, Jaimie M Vega, Teresa V Chin, Kevin Jin, Kelly T Nguyen, Sheldon S Zou, Zain Moin, Shawn Nguyen, Mingshan Xue 薛名杉

Faculty, Staff and Students Publications

An increasing number of pathogenic variants in presynaptic proteins involved in the synaptic vesicle cycle are being discovered in neurodevelopmental disorders. The clinical features of these synaptic vesicle cycle disorders are diverse, but the most prevalent phenotypes include intellectual disability, epilepsy, movement disorders, cerebral visual impairment, and psychiatric symptoms ( Verhage and Sørensen, 2020; Bonnycastle et al., 2021; John et al., 2021; Melland et al., 2021). Among this growing list of synaptic vesicle cycle disorders, the most frequent is STXBP1 encephalopathy caused by de novo heterozygous pathogenic variants in syntaxin-binding protein 1 (STXBP1, also known as …

Final Report Of The Phase Ii Next/Cns-Gct-4 Trial: Gempox Followed By Marrow-Ablative Chemotherapy For Recurrent Intracranial Germ Cell Tumors, Margaret Shatara, Megan Blue, Joseph Stanek, Yin A Liu, Daniel M Prevedello, Pierre Giglio, Vinay K Puduvalli, Sharon L Gardner, Jeffrey C Allen, Kenneth K Wong, Marvin D Nelson, Floyd H Gilles, Roberta H Adams, Jasmine Pauly, Katrina O'Halloran, Ashley S Margol, Girish Dhall, Jonathan L Finlay

Faculty, Staff and Student Publications

Background: Patients with relapsed intracranial germinoma can achieve durable remission with standard chemotherapy regimens and/or reirradiation; however, innovative therapies are required for patients with relapsed and/or refractory intracranial nongerminomatous germ cell tumors (NGGCTs) due to their poor prognosis. Improved outcomes have been reported using reinduction chemotherapy to achieve minimal residual disease, followed by marrow-ablative chemotherapy (HDCx) with autologous hematopoietic progenitor cell rescue (AuHPCR). We conducted a phase II trial evaluating the response and toxicity of a 3-drug combination developed for recurrent intracranial germ cell tumors consisting of gemcitabine, paclitaxel, and oxaliplatin (GemPOx).

Methods: A total of 9 patients with confirmed …

Signaling Mechanisms Underlying Activity-Dependent Integration Of Adult-Born Neurons In The Mouse Olfactory Bulb, Suyang Bao, Juan M Romero, Benjamin D W Belfort, Benjamin R Arenkiel

Duncan NRI Faculty and Staff Publications

Adult neurogenesis has fascinated the field of neuroscience for decades given the prospects of harnessing mechanisms that facilitate the rewiring and/or replacement of adult brain tissue. The subgranular zone of the hippocampus and the subventricular zone of the lateral ventricle are the two main areas in the brain that exhibit ongoing neurogenesis. Of these, adult-born neurons within the olfactory bulb have proven to be a powerful model for studying circuit plasticity, providing a broad and accessible avenue into neuron development, migration, and continued circuit integration within adult brain tissue. This review focuses on some of the recognized molecular and signaling …

Neural And Behavioural State Switching During Hippocampal Dentate Spikes, Jordan S Farrell, Ernie Hwaun, Barna Dudok, Ivan Soltesz

Faculty, Staff and Students Publications

Distinct brain and behavioural states are associated with organized neural population dynamics that are thought to serve specific cognitive functions^1–3. Memory replay events, for example, occur during synchronous population events called sharp-wave ripples in the hippocampus while mice are in an ‘offline’ behavioural state, enabling cognitive mechanisms such as memory consolidation and planning^4–11. But how does the brain re-engage with the external world during this behavioural state and permit access to current sensory information or promote new memory formation? Here we found that the hippocampal dentate spike, an understudied population event that …

A Therapeutically Targetable Positive Feedback Loop Between Nc-Hlx-2-7, Hlx, And Myc That Promotes Group 3 Medulloblastoma, Keisuke Katsushima, Kandarp Joshi, Menglang Yuan, Brigette Romero, Mona Batish, Stacie Stapleton, George Jallo, Elayaraja Kolanthai, Sudipta Seal, Olivier Saulnier, Michael D Taylor, Robert J Wechsler-Reya, Charles G Eberhart, Ranjan J Perera

Faculty, Staff and Students Publications

Recent studies suggest that long non-coding RNAs (lncRNAs) contribute to medulloblastoma (MB) formation and progression. We have identified an lncRNA, lnc-HLX-2-7, as a potential therapeutic target in group 3 (G3) MBs. lnc-HLX-2-7 RNA specifically accumulates in the promoter region of HLX, a sense-overlapping gene of lnc-HLX-2-7, which activates HLX expression by recruiting multiple factors, including enhancer elements. RNA sequencing and chromatin immunoprecipitation reveal that HLX binds to and activates the promoters of several oncogenes, including TBX2, LIN9, HOXM1, and MYC. Intravenous treatment with cerium-oxide-nanoparticle-coated antisense oligonucleotides targeting lnc-HLX-2-7 (CNP-lnc-HLX-2-7) inhibits tumor growth by 40%-50% in an intracranial MB xenograft mouse …

Dopamine Lesions Alter The Striatal Encoding Of Single-Limb Gait, Long Yang, Deepak Singla, Alexander K Wu, Katy A Cross, Sotiris C Masmanidis

Faculty, Staff and Student Publications

The striatum serves an important role in motor control, and neurons in this area encode the body's initiation, cessation, and speed of locomotion. However, it remains unclear whether the same neurons also encode the step-by-step rhythmic motor patterns of individual limbs that characterize gait. By combining high-speed video tracking, electrophysiology, and optogenetic tagging, we found that a sizable population of both D1 and D2 receptor expressing medium spiny projection neurons (MSNs) were phase-locked to the gait cycle of individual limbs in mice. Healthy animals showed balanced limb phase-locking between D1 and D2 MSNs, while dopamine depletion led to stronger phase-locking …

Tmem106b Coding Variant Is Protective And Deletion Detrimental In A Mouse Model Of Tauopathy, George A Edwards, Caleb A Wood, Yang He, Quynh Nguyen, Peter J Kim, Ruben Gomez-Gutierrez, Kyung-Won Park, Yong Xu, Cody Zurhellen, Ismael Al-Ramahi, Joanna L Jankowsky

Duncan NRI Faculty and Staff Publications

TMEM106B is a risk modifier of multiple neurological conditions, where a single coding variant and multiple non-coding SNPs influence the balance between susceptibility and resilience. Two key questions that emerge from past work are whether the lone T185S coding variant contributes to protection, and if the presence of TMEM106B is helpful or harmful in the context of disease. Here, we address both questions while expanding the scope of TMEM106B study from TDP-43 to models of tauopathy. We generated knockout mice with constitutive deletion of TMEM106B, alongside knock-in mice encoding the T186S knock-in mutation (equivalent to the human T185S variant), and …

Childhood Cancer Mutagenesis Caused By Transposase-Derived Pgbd5, Makiko Yamada, Ross R Keller, Rodrigo Lopez Gutierrez, Daniel Cameron, Hiromichi Suzuki, Reeti Sanghrajka, Jake Vaynshteyn, Jeffrey Gerwin, Francesco Maura, William Hooper, Minita Shah, Nicolas Robine, Phillip Demarest, N Sumru Bayin, Luz Jubierre Zapater, Casie Reed, Steven Hébert, Ignas Masilionis, Ronan Chaligne, Nicholas D Socci, Michael D Taylor, Claudia L Kleinman, Alexandra L Joyner, G Praveen Raju, Alex Kentsis

Faculty, Staff and Students Publications

Genomic rearrangements are a hallmark of most childhood tumors, including medulloblastoma, one of the most common brain tumors in children, but their causes remain largely unknown. Here, we show that PiggyBac transposable element derived 5 (Pgbd5) promotes tumor development in multiple developmentally accurate mouse models of Sonic Hedgehog (SHH) medulloblastoma. Most Pgbd5-deficient mice do not develop tumors, while maintaining normal cerebellar development. Ectopic activation of SHH signaling is sufficient to enforce cerebellar granule cell progenitor-like cell states, which exhibit Pgbd5-dependent expression of distinct DNA repair and neurodevelopmental factors. Mouse medulloblastomas expressing Pgbd5 have increased numbers of somatic structural DNA rearrangements, …

Tumor Treating Fields Suppress Tumor Cell Growth And Neurologic Decline In Models Of Spinal Metastases, Daniel Ledbetter, Romulo Augusto Andrade De Almeida, Xizi Wu, Ariel Naveh, Chirag B Patel, Queena Gonzalez, Thomas H Beckham, Robert North, Laurence Rhines, Jing Li, Amol Ghia, David Aten, Claudio Tatsui, Christopher Alvarez-Breckenridge

Faculty, Staff and Student Publications

Spinal metastases can result in severe neurologic compromise and decreased overall survival. Despite treatment advances, local disease progression is frequent, highlighting the need for novel therapies. Tumor treating fields (TTFields) impair tumor cell replication and are influenced by properties of surrounding tissue. We hypothesized that bone's dielectric properties will enhance TTFields-mediated suppression of tumor growth in spinal metastasis models. Computational modeling of TTFields intensity was performed following surgical resection of a spinal metastasis and demonstrated enhanced TTFields intensity within the resected vertebral body. Additionally, luciferase-tagged human KRIB osteosarcoma and A549 lung adenocarcinoma cell lines were cultured in demineralized bone grafts …