Neurology Commons^™

Why Study Mechanisms Of Brain Stimulation Therapies? To Modulate The Right Neurons, In The Right Way, At The Right Time, Matthew J Mcginley, Steven T Lee

Duncan NRI Faculty and Staff Publications

Clinical applications of vagus nerve stimulation (VNS) are burgeoning, but mechanistic work lags behind. In this issue of Neuron, Bowles and colleagues show that VNS timed with positive reinforcement improves motor learning and cortical function by a cholinergic mechanism.

A Potential Role For Substance P In West Nile Virus Neuropathogenesis, Shannon E Ronca, Sarah M Gunter, Rebecca Berry Kairis, Allison Lino, Jonathan Romero, Robia G Pautler, Alan Nimmo, Kristy O Murray

Faculty, Staff and Students Publications

Of individuals who develop West Nile neuroinvasive disease (WNND), ~10% will die and >40% will develop long-term complications. Current treatment recommendations solely focus on supportive care; therefore, we urgently need to identify novel and effective therapeutic options. We observed a correlation between substance P (SP), a key player in neuroinflammation, and its receptor Neurokinin-1 (NK1R). Our study in a wild-type BL6 mouse model found that SP is upregulated in the brain during infection, which correlated with neuroinvasion and damage to the blood−brain barrier. Blocking the SP/NK1R interaction beginning at disease onset modestly improved survival and prolonged time to death in …

The Tfeb-Tgif1 Axis Regulates Emt In Mouse Epicardial Cells, Elena Astanina, Gabriella Doronzo, Davide Corà, Francesco Neri, Salvatore Oliviero, Tullio Genova, Federico Mussano, Emanuele Middonti, Edoardo Vallariello, Chiara Cencioni, Donatella Valdembri, Guido Serini, Federica Limana, Eleonora Foglio, Andrea Ballabio, Federico Bussolino

Duncan NRI Faculty and Staff Publications

Epithelial-mesenchymal transition (EMT) is a complex and pivotal process involved in organogenesis and is related to several pathological processes, including cancer and fibrosis. During heart development, EMT mediates the conversion of epicardial cells into vascular smooth muscle cells and cardiac interstitial fibroblasts. Here, we show that the oncogenic transcription factor EB (TFEB) is a key regulator of EMT in epicardial cells and that its genetic overexpression in mouse epicardium is lethal due to heart defects linked to impaired EMT. TFEB specifically orchestrates the EMT-promoting function of transforming growth factor (TGF) β, and this effect results from activated transcription of thymine-guanine-interacting …

Mir-486 Is Essential For Muscle Function And Suppresses A Dystrophic Transcriptome, Adrienne Samani, Rylie M Hightower, Andrea L Reid, Katherine G English, Michael A Lopez, J Scott Doyle, Michael J Conklin, David A Schneider, Marcas M Bamman, Jeffrey J Widrick, David K Crossman, Min Xie, David Jee, Eric C Lai, Matthew S Alexander

Faculty, Staff and Student Publications

miR-486 is a muscle-enriched microRNA, or “myomiR,” that has reduced expression correlated with Duchenne muscular dystrophy (DMD). To determine the function of miR-486 in normal and dystrophin-deficient muscles and elucidate miR-486 target transcripts in skeletal muscle, we characterized mir-486 knockout mice (mir-486 KO). mir-486 KO mice developed disrupted myofiber architecture, decreased myofiber size, decreased locomotor activity, increased cardiac fibrosis, and metabolic defects were exacerbated in mir-486 KO:mdx5cv (DKO) mice. To identify direct in vivo miR-486 muscle target transcripts, we integrated RNA sequencing and chimeric miRNA eCLIP sequencing to identify key transcripts and pathways that contribute towards mir-486 …

‘Fly-Ing’ From Rare To Common Neurodegenerative Disease Mechanisms, Mengqi Ma, Matthew J Moulton, Shenzhao Lu, Hugo J Bellen

Duncan NRI Faculty and Staff Publications

Genome sequencing advances have enabled researchers and clinicians to probe vast numbers of human variants to distinguish pathogenic from benign variation. Model organisms have been critical in variant assessment and delineating molecular mechanisms of some of the diseases caused by these variants. The fruit fly, Drosophila melanogaster, has played a valuable role in this endeavor, taking advantage of its genetic technologies and established biological knowledge. In this review, we highlight the utility of the fly in studying the function of genes associated with rare neurological diseases that have led to a better understanding of common disease mechanisms. We emphasize …

Removal Of Kcnq2 From Parvalbumin-Expressing Interneurons Improves Anti-Seizure Efficacy Of Retigabine, Junzhan Jing, Corrinne Dunbar, Alina Sonesra, Ana Chavez, Suhyeorn Park, Ryan Yang, Heun Soh, Maxwell Lee, Anastasios V Tzingounis, Edward C Cooper, Xiaolong Jiang, Atul Maheshwari

Duncan NRI Faculty and Staff Publications

Anti-seizure drug (ASD) targets are widely expressed in both excitatory and inhibitory neurons. It remains unknown if the action of an ASD upon inhibitory neurons could counteract its beneficial effects on excitatory neurons (or vice versa), thereby reducing the efficacy of the ASD. Here, we examine whether the efficacy of the ASD retigabine (RTG) is altered after removal of the Kv7 potassium channel subunit KCNQ2, one of its drug targets, from parvalbumin-expressing interneurons (PV-INs). Parvalbumin-Cre (PV-Cre) mice were crossed with Kcnq2-floxed (Kcnq2fl/fl) mice to conditionally delete Kcnq2 from PV-INs. In these conditional knockout mice (cKO, PV-Kcnq2 …

Kctd7 Deficiency Induces Myoclonic Seizures Associated With Purkinje Cell Death And Microvascular Defects, Justine H Liang, Jonathan Alevy, Viktor Akhanov, Ryan Seo, Cory A Massey, Danye Jiang, Joy Zhou, Roy V Sillitoe, Jeffrey L Noebels, Melanie A Samuel

Duncan NRI Faculty and Staff Publications

Mutations in the potassium channel tetramerization domain-containing 7 (KCTD7) gene are associated with a severe neurodegenerative phenotype characterized by childhood onset of progressive and intractable myoclonic seizures accompanied by developmental regression. KCTD7-driven disease is part of a large family of progressive myoclonic epilepsy syndromes displaying a broad spectrum of clinical severity. Animal models of KCTD7-related disease are lacking, and little is known regarding how KCTD7 protein defects lead to epilepsy and cognitive dysfunction. We characterized Kctd7 expression patterns in the mouse brain during development and show that it is selectively enriched in specific regions as the brain matures. We further …

Modeling Neonatal Intraventricular Hemorrhage Through Intraventricular Injection Of Hemoglobin, Brandon A Miller, Shelei Pan, Peter H Yang, Catherine Wang, Amanda L Trout, Dakota Defreitas, Sruthi Ramagiri, Scott D Olson, Jennifer M Strahle

Faculty, Staff and Student Publications

Neonatal intraventricular hemorrhage (IVH) is a common consequence of premature birth and leads to brain injury, posthemorrhagic hydrocephalus (PHH), and lifelong neurological deficits. While PHH can be treated by temporary and permanent cerebrospinal fluid (CSF) diversion procedures (ventricular reservoir and ventriculoperitoneal shunt, respectively), there are no pharmacological strategies to prevent or treat IVH-induced brain injury and hydrocephalus. Animal models are needed to better understand the pathophysiology of IVH and test pharmacological treatments. While there are existing models of neonatal IVH, those that reliably result in hydrocephalus are often limited by the necessity for large-volume injections, which may complicate modeling of …

Novel Dominant And Recessive Variants In Human Robo1 Cause Distinct Neurodevelopmental Defects Through Different Mechanisms, Yan Huang, Mengqi Ma, Xiao Mao, Davut Pehlivan, Oguz Kanca, Feride Un-Candan, Li Shu, Gulsen Akay, Tadahiro Mitani, Shenzhao Lu, Sukru Candan, Hua Wang, Bo Xiao, James R Lupski, Hugo J Bellen

Duncan NRI Faculty and Staff Publications

The Roundabout (Robo) receptors, located on growth cones of neurons, induce axon repulsion in response to the extracellular ligand Slit. The Robo family of proteins controls midline crossing of commissural neurons during development in flies. Mono- and bi-allelic variants in human ROBO1 (HGNC: 10249) have been associated with incomplete penetrance and variable expressivity for a breath of phenotypes, including neurodevelopmental defects such as strabismus, pituitary defects, intellectual impairment, as well as defects in heart and kidney. Here, we report two novel ROBO1 variants associated with very distinct phenotypes. A homozygous missense p.S1522L variant in three affected siblings with nystagmus; and …

Genetic Impairment Of Succinate Metabolism Disrupts Bioenergetic Sensing In Adrenal Neuroendocrine Cancer, Priyanka Gupta, Keehn Strange, Rahul Telange, Ailan Guo, Heather Hatch, Amin Sobh, Jonathan Elie, Angela M Carter, John Totenhagen, Chunfeng Tan, Yogesh A Sonawane, Jiri Neuzil, Amarnath Natarajan, Ashley J Ovens, Jonathan S Oakhill, Thorsten Wiederhold, Karel Pacak, Hans K Ghayee, Laurent Meijer, Sushanth Reddy, James A Bibb

Faculty, Staff and Student Publications

Metabolic dysfunction mutations can impair energy sensing and cause cancer. Loss of function of the mitochondrial tricarboxylic acid (TCA) cycle enzyme subunit succinate dehydrogenase B (SDHB) results in various forms of cancer typified by pheochromocytoma (PC). Here we delineate a signaling cascade where the loss of SDHB induces the Warburg effect, triggers dysregulation of [Ca2+]i, and aberrantly activates calpain and protein kinase Cdk5, through conversion of its cofactor from p35 to p25. Consequently, aberrant Cdk5 initiates a phospho-signaling cascade where GSK3 inhibition inactivates energy sensing by AMP kinase through dephosphorylation of the AMP kinase γ subunit, PRKAG2. Overexpression of p25-GFP …

Genetic Impairment Of Succinate Metabolism Disrupts Bioenergetic Sensing In Adrenal Neuroendocrine Cancer, Priyanka Gupta, Keehn Strange, Rahul Telange, Ailan Guo, Heather Hatch, Amin Sobh, Jonathan Elie, Angela M Carter, John Totenhagen, Chunfeng Tan, Yogesh A Sonawane, Jiri Neuzil, Amarnath Natarajan, Ashley J Ovens, Jonathan S Oakhill, Thorsten Wiederhold, Karel Pacak, Hans K Ghayee, Laurent Meijer, Sushanth Reddy, James A Bibb

Faculty, Staff and Student Publications

Metabolic dysfunction mutations can impair energy sensing and cause cancer. Loss of function of the mitochondrial tricarboxylic acid (TCA) cycle enzyme subunit succinate dehydrogenase B (SDHB) results in various forms of cancer typified by pheochromocytoma (PC). Here we delineate a signaling cascade where the loss of SDHB induces the Warburg effect, triggers dysregulation of [Ca

Regulation Of Microglial Activation In Stroke In Aged Mice: A Translational Study, Conelius Ngwa, Abdullah Al Mamun, Shaohua Qi, Romana Sharmeen, Yan Xu, Fudong Liu

Faculty, Staff and Student Publications

Numerous neurochemical changes occur with aging and stroke mainly affects the elderly. Our previous study has found interferon regulatory factor 5 (IRF5) and 4 (IRF4) regulate neuroinflammation in young stroke mice. However, whether the IRF5-IRF4 regulatory axis has the same effect in aged brains is not known. In this study, aged (18-20-month-old), microglial IRF5 or IRF4 conditional knockout (CKO) mice were subjected to a 60-min middle cerebral artery occlusion (MCAO). Stroke outcomes were quantified at 3d after MCAO. Flow cytometry and ELISA were performed to evaluate microglial activation and immune responses. We found aged microglia express higher levels of IRF5 …

Integrated Regulation Of Pka By Fast And Slow Neurotransmission In The Nucleus Accumbens Controls Plasticity And Stress Responses, Rachel Thomas, Adan Hernandez, David R Benavides, Wei Li, Chunfeng Tan, Alan Umfress, Florian Plattner, Ayanabha Chakraborti, Lucas Pozzo-Miller, Susan S Taylor, James A Bibb

Faculty, Staff and Student Publications

Cortical glutamate and midbrain dopamine neurotransmission converge to mediate striatum-dependent behaviors, while maladaptations in striatal circuitry contribute to mental disorders. However, the crosstalk between glutamate and dopamine signaling has not been entirely elucidated. Here we uncover a molecular mechanism by which glutamatergic and dopaminergic signaling integrate to regulate cAMP-dependent protein kinase (PKA) via phosphorylation of the PKA regulatory subunit, RIIβ. Using a combination of biochemical, pharmacological, neurophysiological, and behavioral approaches, we find that glutamate-dependent reduction in cyclin-dependent kinase 5 (Cdk5)-dependent RIIβ phosphorylation alters the PKA holoenzyme autoinhibitory state to increase PKA signaling in response to dopamine. Furthermore, we show that …

Twist1 Interacts With Β/Δ-Catenins During Neural Tube Development And Regulates Fate Transition In Cranial Neural Crest Cells, Jessica W Bertol, Shelby Johnston, Rabia Ahmed, Victoria K Xie, Kelsea M Hubka, Lissette Cruz, Larissa Nitschke, Marta Stetsiv, Jeremy P Goering, Paul Nistor, Sally Lowell, Hanne Hoskens, Peter Claes, Seth M Weinberg, Irfan Saadi, Mary C Farach-Carson, Walid D Fakhouri

Faculty, Staff and Student Publications

Cell fate determination is a necessary and tightly regulated process for producing different cell types and structures during development. Cranial neural crest cells (CNCCs) are unique to vertebrate embryos and emerge from the neural plate borders into multiple cell lineages that differentiate into bone, cartilage, neurons and glial cells. We have previously reported that Irf6 genetically interacts with Twist1 during CNCC-derived tissue formation. Here, we have investigated the mechanistic role of Twist1 and Irf6 at early stages of craniofacial development. Our data indicate that TWIST1 is expressed in endocytic vesicles at the apical surface and interacts with β/δ-catenins during neural …

Electrophysiological Alterations Driving Pain-Associated Spontaneous Activity In Human Sensory Neuron Somata Parallel Alterations Described In Spontaneously Active Rodent Nociceptors, Robert Y North, Max A Odem, Yan Li, Claudio Esteves Tatsui, Ryan M Cassidy, Patrick M Dougherty, Edgar T Walters

Faculty, Staff and Student Publications

Neuropathic pain in rodents can be driven by ectopic spontaneous activity (SA) generated by sensory neurons in dorsal root ganglia (DRG). The recent demonstration that SA in dissociated human DRG neurons is associated with reported neuropathic pain in patients enables a detailed comparison of pain-linked electrophysiological alterations driving SA in human DRG neurons to alterations that distinguish SA in nociceptors from SA in low-threshold mechanoreceptors (LTMRs) in rodent neuropathy models. Analysis of recordings from dissociated somata of patient-derived DRG neurons showed that SA and corresponding pain in both sexes were significantly associated with the three functional electrophysiological alterations sufficient to …

Ankle2-Related Microcephaly: A Variable Microcephaly Syndrome Resembling Zika Infection, Ajay X Thomas, Nichole Link, Laurie A Robak, Gail Demmler-Harrison, Emily C Pao, Audrey E Squire, Savannah Michels, Julie S Cohen, Anne Comi, Paolo Prontera, Alberto Verrotti Di Pianella, Giuseppe Di Cara, Livia Garavelli, Stefano Giuseppe Caraffi, Carlo Fusco, Roberta Zuntini, Kendall C Parks, Elliott H Sherr, Mais O Hashem, Sateesh Maddirevula, Fowzan S Alkuraya, Isphana A F Contractar, Jennifer E Neil, Christopher A Walsh, Hugo J Bellen, Hsiao-Tuan Chao, Robin D Clark, Ghayda M Mirzaa

Duncan NRI Faculty and Staff Publications

Objective: This study delineates the clinical and molecular spectrum of ANKLE2-related microcephaly (MIC), as well as highlights shared pathological mechanisms between ANKLE2 and the Zika virus.

Methods: We identified 12 individuals with MIC and variants in ANKLE2 with a broad range of features. Probands underwent thorough phenotypic evaluations, developmental assessments, and anthropometric measurements. Brain imaging studies were systematically reviewed for developmental abnormalities. We functionally interrogated a subset of identified ANKLE2 variants in Drosophila melanogaster.

Results: All individuals had MIC (z-score ≤ -3), including nine with congenital MIC. We identified a broad range of brain abnormalities including simplified cortical gyral pattern, …

Sox9 Directs Divergent Epigenomic States In Brain Tumor Subtypes, Debosmita Sardar, Hsiao-Chi Chen, Amanda Reyes, Srinidhi Varadharajan, Antrix Jain, Carrie Mohila, Rachel Curry, Brittney Lozzi, Kavitha Rajendran, Alexis Cervantes, Kwanha Yu, Ali Jalali, Ganesh Rao, Stephen C Mack, Benjamin Deneen

Duncan NRI Faculty and Staff Publications

Epigenetic dysregulation is a universal feature of cancer that results in altered patterns of gene expression that drive malignancy. Brain tumors exhibit subtype-specific epigenetic alterations; however, the molecular mechanisms responsible for these diverse epigenetic states remain unclear. Here, we show that the developmental transcription factor Sox9 differentially regulates epigenomic states in high-grade glioma (HGG) and ependymoma (EPN). Using our autochthonous mouse models, we found that Sox9 suppresses HGG growth and expands associated H3K27ac states, while promoting ZFTA-RELA (ZR

Cd11bhigh B Cells Increase After Stroke And Regulate Microglia: Cd11bhigh B Cells Increase After Stroke And Regulate Mg, Janelle M Korf, Pedram Honarpisheh, Eric C Mohan, Anik Banerjee, Maria P Blasco-Conesa, Parisa Honarpisheh, Gary U Guzman, Romeesa Khan, Bhanu P Ganesh, Amy L Hazen, Juneyoung Lee, Aditya Kumar, Louise D Mccullough, Anjali Chauhan

Faculty, Staff and Student Publications

Recent studies have highlighted the deleterious contributions of B cells to post-stroke recovery and cognitive decline. Different B cell subsets have been proposed based on expression levels of transcription factors (e.g. T-bet) as well as specific surface proteins. CD11b (α-chain of integrin) is expressed by several immune cell types and is involved in regulation of cell motility, phagocytosis, and other essential functions of host immunity. Although B cells express CD11b, the CD11b^high subset of B cells has not been well characterized, especially in immune dysregulation seen with aging and after stroke. Here, we investigate the role of CD11b^{high …}

Neuronal Activity Induces Glucosylceramide That Is Secreted Via Exosomes For Lysosomal Degradation In Glia, Liping Wang, Guang Lin, Zhongyuan Zuo, Yarong Li, Seul Kee Byeon, Akhilesh Pandey, Hugo J Bellen

Duncan NRI Faculty and Staff Publications

Recessive variants in GBA1 cause Gaucher disease, a prevalent form of lysosome storage disease. GBA1 encodes a lysosomal enzyme that hydrolyzes glucosylceramide (GlcCer) into glucose and ceramide. Its loss causes lysosomal dysfunction and increased levels of GlcCer. We generated a null allele of the Drosophila ortholog Gba1b by inserting the Gal4 using CRISPR-Cas9. Here, we show that Gba1b is expressed in glia but not in neurons. Glial-specific knockdown recapitulates the defects found in Gba1b mutants, and these can be rescued by glial expression of human GBA1. We show that GlcCer is synthesized upon neuronal activity, and it is transported …

Renin-Angiotensin System In Huntington's Disease: Evidence From Animal Models And Human Patients, Lucas M Kangussu, Natalia P Rocha, Priscila A C Valadão, Thatiane C G Machado, Kívia B Soares, Julliane V Joviano-Santos, Leigh B Latham, Gabriela D Colpo, Ana Flávia Almeida-Santos, Erin Furr Stimming, Ana Cristina Simões E Silva, Antônio L Teixeira, Aline Silva Miranda, Cristina Guatimosim

Faculty, Staff and Student Publications

The Renin-Angiotensin System (RAS) is expressed in the central nervous system and has important functions that go beyond blood pressure regulation. Clinical and experimental studies have suggested that alterations in the brain RAS contribute to the development and progression of neurodegenerative diseases. However, there is limited information regarding the involvement of RAS components in Huntington's disease (HD). Herein, we used the HD murine model, (BACHD), as well as samples from patients with HD to investigate the role of both the classical and alternative axes of RAS in HD pathophysiology. BACHD mice displayed worse motor performance in different behavioral tests alongside …

Small Rna Signatures Of Acute Ischemic Stroke In L1cam Positive Extracellular Vesicles, Michael A Lopez, Ying Si, Xianzhen Hu, Valentyna Williams, Fuad Qushair, Jackson Carlyle, Lyndsy Alesce, Michael Conklin, Shawn Gilbert, Marcas M Bamman, Matthew S Alexander, Peter H King

Faculty, Staff and Student Publications

Duchenne muscular dystrophy (DMD) is an X-linked recessive disease characterized by skeletal muscle instability, progressive muscle wasting, and fibrosis. A major driver of DMD pathology stems from aberrant upregulation of transforming growth factor β (TGFβ) signaling. In this report, we investigated the major transducers of TGFβ signaling, i.e., receptor Smads (R-Smads), in DMD patient skeletal muscle and observed a 48-fold increase in Smad8 mRNA. Smad1, Smad2, Smad3, and Smad5 mRNA were only minimally increased. A similar pattern was observed in the muscle from the mdx5cv mouse. Western blot analysis showed upregulation of phosphorylated Smad1, Smad5, and Smad8 …

Gene-Based Therapeutics For Rare Genetic Neurodevelopmental Psychiatric Disorders, Beverly L Davidson, Guangping Gao, Elizabeth Berry-Kravis, Allison M Bradbury, Carsten Bönnemann, Joseph D Buxbaum, Gavin R Corcoran, Steven J Gray, Heather Gray-Edwards, Robin J Kleiman, Adam J Shaywitz, Dan Wang, Huda Y Zoghbi, Terence R Flotte, Sitra Tauscher-Wisniewski, Cynthia J Tifft, Mustafa Sahin

Duncan NRI Faculty and Staff Publications

We are in an emerging era of gene-based therapeutics with significant promise for rare genetic disorders. The potential is particularly significant for genetic central nervous system disorders that have begun to achieve Food and Drug Administration approval for select patient populations. This review summarizes the discussions and presentations of the National Institute of Mental Health-sponsored workshop "Gene-Based Therapeutics for Rare Genetic Neurodevelopmental Psychiatric Disorders," which was held in January 2021. Here, we distill the points raised regarding various precision medicine approaches related to neurodevelopmental and psychiatric disorders that may be amenable to gene-based therapies.

Transcription Factor Runx3 Mediates Plasticity Of Thgm Cells Toward Th1 Phenotype, Javad Rasouli, Giacomo Casella, Weifeng Zhang, Dan Xiao, Gaurav Kumar, Paolo Fortina, Guang-Xian Zhang, Bogoljub Ciric, Abdolmohamad Rostami

Department of Neurology Faculty Papers

GM-CSF-producing T helper (Th) cells play a crucial role in the pathogenesis of autoimmune diseases such as multiple sclerosis (MS). Recent studies have identified a distinct population of GM-CSF-producing Th cells, named ThGM cells, that also express cytokines TNF, IL-2, and IL-3, but lack expression of master transcription factors (TF) and signature cytokines of commonly recognized Th cell lineages. ThGM cells are highly encephalitogenic in a mouse model of MS, experimental autoimmune encephalomyelitis (EAE). Similar to Th17 cells, in response to IL-12, ThGM cells upregulate expression of T-bet and IFN-γ and switch their phenotype to Th1. Here we show that …

Transmission, Strain Diversity, And Zoonotic Potential Of Chronic Wasting Disease, Sandra Pritzkow

Faculty, Staff and Student Publications

Chronic wasting disease (CWD) is a prion disease affecting several species of captive and free-ranging cervids. In the past few decades, CWD has been spreading uncontrollably, mostly in North America, resulting in a high increase of CWD incidence but also a substantially higher number of geographical regions affected. The massive increase in CWD poses risks at several levels, including contamination of the environment, transmission to animals cohabiting with cervids, and more importantly, a putative transmission to humans. In this review, I will describe the mechanisms and routes responsible for the efficient transmission of CWD, the strain diversity of natural CWD, …

Gut Dysbiosis And Age-Related Neurological Diseases In Females, Janelle M Korf, Bhanu P Ganesh, Louise D Mccullough

Faculty, Staff and Student Publications

Historically, females have been underrepresented in biological research. With increased interest in the gut microbiome and the gut-brain axis, it is important for researchers to pursue studies that consider sex as a biological variable. The composition of the gut microbiome is influenced by environmental factors, disease, diet, and varies with age and by sex. Detrimental changes in the gut microbiome, referred to as dysbiosis, is believed to influence the development and progression of age-related neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and stroke. Many are investigating the changes in microbial populations in order or to better understand …

Chemotherapy Coupled To Macrophage Inhibition Induces T-Cell And B-Cell Infiltration And Durable Regression In Triple-Negative Breast Cancer, Swarnima Singh, Nigel Lee, Diego A Pedroza, Igor L Bado, Clark Hamor, Licheng Zhang, Sergio Aguirre, Jingyuan Hu, Yichao Shen, Yitian Xu, Yang Gao, Na Zhao, Shu-Hsia Chen, Ying-Wooi Wan, Zhandong Liu, Jeffrey T Chang, Daniel Hollern, Charles M Perou, Xiang H F Zhang, Jeffrey M Rosen

Duncan NRI Faculty and Staff Publications

Immunosuppressive elements within the tumor microenvironment, such as tumor-associated macrophages (TAM), can present a barrier to successful anti-tumor responses by cytolytic T cells. Here we employed preclinical syngeneic p53 null mouse models of triple-negative breast cancer (TNBC) to develop a treatment regimen that harnessed the immunostimulatory effects of low-dose cyclophosphamide coupled with the pharmacologic inhibition of TAMs using either a small molecule CSF1R inhibitor or an anti-CSF1R antibody. This therapeutic combination was effective in treating several highly aggressive TNBC murine mammary tumor and lung metastasis models. Single cell RNA sequencing characterized tumor-infiltrating lymphocytes (TIL) including helper T cells and antigen-presenting …

A Peptide Blocking The Adora1-Neurabin Interaction Is Anticonvulsant And Inhibits Epilepsy In An Alzheimer's Model, Shalini Saggu, Yunjia Chen, Liping Chen, Diana Pizarro, Sandipan Pati, Wen Jing Law, Lori Mcmahon, Kai Jiao, Qin Wang

Faculty, Staff and Student Publications

Epileptic seizures are common sequelae of stroke, acute brain injury, and chronic neurodegenerative diseases, including Alzheimer's disease (AD), and cannot be effectively controlled in approximately 40% of patients, necessitating the development of novel therapeutic agents. Activation of the A1 receptor (A1R) by endogenous adenosine is an intrinsic mechanism to self-terminate seizures and protect neurons from excitotoxicity. However, targeting A1R for neurological disorders has been hindered by side effects associated with its broad expression outside the nervous system. Here we aim to target the neural-specific A1R/neurabin/regulator of G protein signaling 4 (A1R/neurabin/RGS4) complex that dictates A1R signaling strength and response outcome …

A Wireless Millimetric Magnetoelectric Implant For The Endovascular Stimulation Of Peripheral Nerves, Joshua C Chen, Peter Kan, Zhanghao Yu, Fatima Alrashdan, Roberto Garcia, Amanda Singer, C S Edwin Lai, Ben Avants, Scott Crosby, Zhongxi Li, Boshuo Wang, Michelle M Felicella, Ariadna Robledo, Angel V Peterchev, Stefan M Goetz, Jeffrey D Hartgerink, Sunil A Sheth, Kaiyuan Yang, Jacob T Robinson

Faculty, Staff and Student Publications

Implantable bioelectronic devices for the simulation of peripheral nerves could be used to treat disorders that are resistant to traditional pharmacological therapies. However, for many nerve targets, this requires invasive surgeries and the implantation of bulky devices (about a few centimetres in at least one dimension). Here we report the design and in vivo proof-of-concept testing of an endovascular wireless and battery-free millimetric implant for the stimulation of specific peripheral nerves that are difficult to reach via traditional surgeries. The device can be delivered through a percutaneous catheter and leverages magnetoelectric materials to receive data and power through tissue via …

Co-Transmitting Neurons In The Lateral Septal Nucleus Exhibit Features Of Neurotransmitter Switching, Patrick J Hunt, Mikhail Kochukov, Brandon T Pekarek, Benjamin D W Belfort, Juan M Romero, Jessica L Swanson, Benjamin R Arenkiel

Faculty, Staff and Students Publications

The lateral septal nucleus (LSN) is a highly interconnected region of the central brain whose activity regulates widespread circuitry. As such, the mechanisms that govern neuronal activity within the LSN have far-reaching implications on numerous brain-wide nuclei, circuits, and behaviors. We found that GABAergic neurons within the LSN express markers that mediate the release of acetylcholine (ACh). Moreover, we show that these vGATLSN neurons release both GABA and ACh onto local glutamatergic LSN neurons. Using both short-term and long-term neuronal labeling techniques we observed expression of the cholinergic neuron marker Choline Acetyltransferase (ChAT) in vGATLSN neurons. These findings provide evidence …

Expression Of 4e-Bp1 In Juvenile Mice Alleviates Mtor-Induced Neuronal Dysfunction And Epilepsy, Lena H Nguyen, Youfen Xu, Travorn Mahadeo, Longbo Zhang, Tiffany V Lin, Heather A Born, Anne E Anderson, Angélique Bordey

Faculty, Staff and Students Publications

Hyperactivation of the mTOR pathway during foetal neurodevelopment alters neuron structure and function, leading to focal malformation of cortical development and intractable epilepsy. Recent evidence suggests a role for dysregulated cap-dependent translation downstream of mTOR signalling in the formation of focal malformation of cortical development and seizures. However, it is unknown whether modifying translation once the developmental pathologies are established can reverse neuronal abnormalities and seizures. Addressing these issues is crucial with regards to therapeutics because these neurodevelopmental disorders are predominantly diagnosed during childhood, when patients present with symptoms. Here, we report increased phosphorylation of the mTOR effector and translational …