Neurosciences Commons^™

Early Morphological Changes Of The Rectus Femoris Muscle And Deep Fascia In Ullrich Congenital Muscular Dystrophy, Patrizia Sabatelli, Luciano Merlini, Alberto Di Martino, Vittoria Cenni, Cesare Faldini

Department of Medicine Faculty Papers

Ullrich congenital muscular dystrophy (UCMD) is a severe form of muscular dystrophy caused by the loss of function of collagen VI, a critical component of the muscle-tendon matrix. Magnetic resonance imaging of UCMD patients’ muscles shows a peculiar rim of abnormal signal at the periphery of each muscle, and a relative sparing of the internal part. The mechanism/s involved in the early fat substitution of muscle fiber at the periphery of muscles remain elusive. We studied a muscle biopsy of the rectus femoris/deep fascia (DF) of a 3-year-old UCMD patient, with a homozygous mutation in the COL6A2 gene. By immunohistochemical …

Single-Cell Systems Neuroscience: A Growing Frontier In Mental Illness, Sean O'Sullivan

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

The development of effective treatments for psychiatric disease has been disappointing in recent decades given the advancements in neuroscience. Moreover, rising rates of mental illness such as addiction and depression compel scientists and physicians to discover novel and creative solutions. One such approach that has proven effective is systems neuroscience: A focus on networks as opposed to mechanism. Further, investigation at the single-cell and circuit level is likely to be fruitful in such endeavors as this resolution describes the functional psychopathology that allows for intervention.

Treatment-Specific Hippocampal Subfield Volume Changes With Antidepressant Medication Or Cognitive-Behavior Therapy In Treatment-Naive Depression., Hua-Hsin Tai, Jungho Cha, Faezeh Vedaei, Boadie W Dunlop, W Edward Craighead, Helen S Mayberg, Ki Sueng Choi

Department of Neuroscience Faculty Papers

Background: Hippocampal atrophy has been consistently reported in major depressive disorder with more recent focus on subfields. However, literature on hippocampal volume changes after antidepressant treatment has been limited. The first-line treatments for depression include antidepressant medication (ADM) or cognitive-behavior therapy (CBT). To understand the differential effects of CBT and ADM on the hippocampus, we investigated the volume alterations of hippocampal subfields with treatment, outcome, and chronicity in treatment-naïve depression patients. Methods: Treatment-naïve depressed patients from the PReDICT study were included in this analysis. A total of 172 patients who completed 12 weeks of randomized treatment with CBT (n …

The Effects Of Molecular Crowding And Cpg Hypermethylation On Dna G-Quadruplexes Formed By The C9orf72 Nucleotide Repeat Expansion., Kadir A. Ozcan, Layla T. Ghaffari, Aaron R. Haeusler

Farber Institute for Neuroscience Faculty Papers

A nucleotide repeat expansion (NRE), (G₄C₂)_n, located in a classically noncoding region of C9orf72 (C9), is the most common genetic mutation associated with ALS/FTD. There is increasing evidence that nucleic acid structures formed by the C9-NRE may both contribute to ALS/FTD, and serve as therapeutic targets, but there is limited characterization of these nucleic acid structures under physiologically and disease relevant conditions. Here we show in vitro that the C9-NRE DNA can form both parallel and antiparallel DNA G-quadruplex (GQ) topological structures and that the structural preference of these DNA GQs can be dependent …

Effects Of The Tailored Activity Program (Tap) On Dementia-Related Symptoms, Health Events And Caregiver Wellbeing: A Randomized Controlled Trial, Laura N Gitlin, Katherine Marx, Catherine V. Piersol, Nancy A Hodgson, Jin Huang, David L Roth, Constantine Lyketsos

Department of Occupational Therapy Faculty Papers

BACKGROUND: People living with dementia (PLWD) and caregivers are adversely impacted by lack of meaningful activity leading to worse symptoms and impaired quality-of-life. There is a critical need to develop effective and well-tolerated treatments that mitigate clinical symptoms, engage PLWD and support caregiver wellbeing. We tested whether, compared to attention control, the Tailored Activity Program (TAP) reduced clinical symptoms and health-related events, and improved caregiver wellbeing, and if TAP activities were well-tolerated.

METHODS: We conducted a single-blind randomized controlled trial among 250 dyads recruited from Baltimore-Washington DC (2012-2016) with a dementia diagnosis and clinically significant agitation/aggression. Dyads were randomized to …

The Ephb2 Receptor Uses Homotypic, Head-To-Tail Interactions Within Its Ectodomain As An Autoinhibitory Control Mechanism, Yan Xu, Dorothea Robev, Nayanendu Saha, Bingcheng Wang, Matthew B. Dalva, Kai Xu, Juha P. Himanen, Dimitar B. Nikolov

Department of Neuroscience Faculty Papers

The Eph receptor tyrosine kinases and their ephrin ligands direct axon pathfinding and neuronal cell migration, as well as mediate many other cell–cell communication events. Their dysfunctional signaling has been shown to lead to various diseases, including cancer. The Ephs and ephrins both localize to the plasma membrane and, upon cell–cell contact, form extensive signaling assemblies at the contact sites. The Ephs and the ephrins are divided into A and B subclasses based on their sequence conservation and affinities for each other. The molecular details of Eph–ephrin recognition have been previously revealed and it has been documented that ephrin binding …

Neuronal Nsun2 Deficiency Produces Trna Epitranscriptomic Alterations And Proteomic Shifts Impacting Synaptic Signaling And Behavior., J Blaze, A Navickas, H L Phillips, S Heissel, A Plaza-Jennings, S Miglani, H Asgharian, M Foo, C D Katanski, C P Watkins, Z T Pennington, B Javidfar, S Espeso-Gil, B Rostandy, H Alwaseem, C G Hahn, H Molina, D J Cai, T Pan, W D Yao, H Goodarzi, F Haghighi, S Akbarian

Department of Neuroscience Faculty Papers

Epitranscriptomic mechanisms linking tRNA function and the brain proteome to cognition and complex behaviors are not well described. Here, we report bi-directional changes in depression-related behaviors after genetic disruption of neuronal tRNA cytosine methylation, including conditional ablation and transgene-derived overexpression of Nsun2 in the mouse prefrontal cortex (PFC). Neuronal Nsun2-deficiency was associated with a decrease in tRNA m⁵C levels, resulting in deficits in expression of 70% of tRNA^Gly isodecoders. Altogether, 1488/5820 proteins changed upon neuronal Nsun2-deficiency, in conjunction with glycine codon-specific defects in translational efficiencies. Loss of Gly-rich proteins critical for glutamatergic neurotransmission was associated with impaired …

Caldag-Gefi Mediates Striatal Cholinergic Modulation Of Dendritic Excitability, Synaptic Plasticity And Psychomotor Behaviors., Jill R. Crittenden, Shenyu Zhai, Magdalena Sauvage, Takashi Kitsukawa, Eric Burguière, Morgane Thomsen, Hui Zhang, Cinzia Costa, Giuseppina Martella, Veronica Ghiglieri, Barbara Picconi, Karen A. Pescatore, Ellen M. Unterwald, Walker S. Jackson, David E. Housman, S. Barak Caine, David Sulzer, Paolo Calabresi, Anne C. Smith, D. James Surmeier, Ann M. Graybiel

Department of Neuroscience Faculty Papers

CalDAG-GEFI (CDGI) is a protein highly enriched in the striatum, particularly in the principal spiny projection neurons (SPNs). CDGI is strongly down-regulated in two hyperkinetic conditions related to striatal dysfunction: Huntington's disease and levodopa-induced dyskinesia in Parkinson's disease. We demonstrate that genetic deletion of CDGI in mice disrupts dendritic, but not somatic, M1 muscarinic receptors (M1Rs) signaling in indirect pathway SPNs. Loss of CDGI reduced temporal integration of excitatory postsynaptic potentials at dendritic glutamatergic synapses and impaired the induction of activity-dependent long-term potentiation. CDGI deletion selectively increased psychostimulant-induced repetitive behaviors, disrupted sequence learning, and eliminated M1R blockade of cocaine self-administration. …

On The Road From Phenotypic Plasticity To Stem Cell Therapy., Lorraine Iacovitti

Farber Institute for Neuroscience Faculty Papers

In 1981, I published a paper in the first issue of The Journal of Neuroscience with my postdoctoral mentor, Richard Bunge. At that time, the long-standing belief that each neuron expressed only one neurotransmitter, known as Dale's Principle (Dale, 1935), was being hotly debated following a report by French embryologist Nicole Le Douarin showing that neural crest cells destined for one transmitter phenotype could express characteristics of another if transplanted to alternate sites in the developing embryo (Le Douarin, 1980). In the Bunge laboratory, we were able to more directly test the question of phenotypic plasticity in the controlled environment …

A Stress-Free Strategy To Correct Point Mutations In Patient Ips Cells, Jingli Cai, Elizabeth Kropf, Ya-Ming Hou, Lorraine Iacovitti

Department of Biochemistry and Molecular Biology Faculty Papers

When studying patient specific induced pluripotent stem cells (iPS cells) as a disease model, the ideal control is an isogenic line that has corrected the point mutation, instead of iPS cells from siblings or other healthy subjects. However, repairing a point mutation in iPS cells even with the newly developed CRISPR-Cas9 technique remains difficult and time-consuming. Here we report a strategy that makes the Cas9 “knock-in” methodology both hassle-free and error-free. Instead of selecting a Cas9 recognition site close to the point mutation, we chose a site located in the nearest intron. We constructed a donor template with the fragment …

Input-Output Signal Processing Plasticity Of Vagal Motor Neurons In Response To Cardiac Ischemic Injury., Jonathan Gorky, Alison Moss, Marina Balycheva, Rajanikanth Vadigepalli, James S. Schwaber

Computational Medicine Center Faculty Papers

Vagal stimulation is emerging as the next frontier in bioelectronic medicine to modulate peripheral organ health and treat disease. The neuronal molecular phenotypes in the dorsal motor nucleus of the vagus (DMV) remain largely unexplored, limiting the potential for harnessing the DMV plasticity for therapeutic interventions. We developed a mesoscale single-cell transcriptomics data from hundreds of DMV neurons under homeostasis and following physiological perturbations. Our results revealed that homeostatic DMV neuronal states can be organized into distinguishable input-output signal processing units. Remote ischemic preconditioning induced a distinctive shift in the neuronal states toward diminishing the role of inhibitory inputs, with …

Conservation And Innovation: Versatile Roles For Lrp4 In Nervous System Development., Alison T. Depew, Timothy J. Mosca

Department of Neuroscience Faculty Papers

As the nervous system develops, connections between neurons must form to enable efficient communication. This complex process of synaptic development requires the coordination of a series of intricate mechanisms between partner neurons to ensure pre- and postsynaptic differentiation. Many of these mechanisms employ transsynaptic signaling via essential secreted factors and cell surface receptors to promote each step of synaptic development. One such cell surface receptor, LRP4, has emerged as a synaptic organizer, playing a critical role in conveying extracellular signals to initiate diverse intracellular events during development. To date, LRP4 is largely known for its role in development of the …

Rapid Decline In Telestroke Consults In The Setting Of Covid-19., Syed O. Shah., Robin Dharia, Jaime Stazi, Maureen Deprince, Robert H. Rosenwasswer

Farber Institute for Neuroscience Faculty Papers

Background and Purpose: As coronavirus disease 2019 (COVID-19) continues to be a global pandemic, there is a growing body of evidence suggesting that incidence of diseases that require emergent care, particularly myocardial infarction and ischemic stroke, has declined rapidly. The objective of this study is to quantify our experience of telestroke (TS) consults at a large tertiary comprehensive stroke center during the COVID-19 pandemic.

Methods: We retrospectively reviewed TS consults of patients presenting to our neuroscience network. Those with a confirmed diagnosis of acute ischemic stroke or transient ischemia attack were included. Data were compared from April 1, 2019, to …

Infection And Risk Of Parkinson's Disease, Richard Jay Smeyne, Alastair J Noyce, Matthew D. Byrne, Rodolfo Savica, Connie Marras

Department of Neuroscience Faculty Papers

Parkinson's disease (PD) is thought to be caused by a combination of genetic and environmental factors. Bacterial or viral infection has been proposed as a potential risk factor, and there is supporting although not entirely consistent epidemiologic and basic science evidence to support its role. Encephalitis caused by influenza has included parkinsonian features. Epidemiological evidence is most compelling for an association between PD and hepatitis C virus. Infection with Helicobacter pylori may be associated not only with PD risk but also response to levodopa. Rapidly evolving knowledge regarding the role of the microbiome also suggests a role of resident bacteria …

Development Of A Method Using Retrograde Neuronal Tracers To Neuroanatomically Characterize Respiratory Neural Circuitry, Samantha Thomas, Angelo Lepore

Phase 1

Introduction:

Loss of respiratory function is one of the leading causes of death following spinal cord injury (SCI). Existing studies have demonstrated that pre-phrenic interneurons (PPIN’s) can be recruited into the phrenic motor neuron (PhMN) pathway following cervical SCI and may contribute to respiratory recovery, but there is still a lack of information detailing the nature of these changes and the extent they may improve diaphragm function. This project aims to validate a method of utilizing neuronal tracers to further characterize the intact respiratory circuitry.

Methods:

This study was carried out using a rat model. A fluorophore-conjugated retrograde neuronal …

A High Affinity, Partial Antagonist Effect Of 3,4-Diaminopyridine Mediates Action Potential Broadening And Enhancement Of Transmitter Release At Nmjs, Kristine S Ojala, Scott P Ginebaugh, Man Wu, Evan W Miller, Gloria Ortiz, Manuel Covarrubias, Stephen D Meriney

Department of Neuroscience Faculty Papers

3,4-Diaminopyridine (3,4-DAP) increases transmitter release from neuromuscular junctions (NMJs), and low doses of 3,4-DAP (estimated to reach ∼1 μM in serum) are the Food and Drug Administration (FDA)-Approved treatment for neuro muscular weakness caused by Lambert-Eaton myasthenic syn drome. Canonically, 3,4-DAP is thought to block voltage-gated potassium (Kv) channels, resulting in prolongation of the pre synaptic action potential (AP). However, recent reports have shown that low millimolar concentrations of 3,4-DAP have an off-Target agonist effect on the Cav1 subtype ("L-Type") of voltage-gated calcium (Cav) channels and have speculated that this agonist effect might contribute to 3,4-DAP effects on transmitter release …

Sleep Induction By Mechanosensory Stimulation In Drosophila., Arzu Öztürk-Çolak, Sho Inami, Joseph R. Buchler, Patrick D. Mcclanahan, Andri Cruz, Christopher Fang-Yen, Kyunghee Koh

Department of Neuroscience Faculty Papers

People tend to fall asleep when gently rocked or vibrated. Experimental studies have shown that rocking promotes sleep in humans and mice. However, the mechanisms underlying the phenomenon are not well understood. A habituation model proposes that habituation, a form of non-associative learning, mediates sleep induction by monotonous stimulation. Here, we show that gentle vibration promotes sleep in Drosophila in part through habituation. Vibration-induced sleep (VIS) leads to increased homeostatic sleep credit and reduced arousability, and can be suppressed by heightened arousal or reduced GABA signaling. Multiple mechanosensory organs mediate VIS, and the magnitude of VIS depends on vibration frequency …

Facial Grimace Testing As An Assay Of Neuropathic Pain-Related Behavior In A Mouse Model Of Cervical Spinal Cord Injury., Nicolette M Heinsinger, Gabrielle Spagnuolo, R Vivian Allahyari, Simon Galer, Tyler Fox, David A Jaffe, Samantha J Thomas, Lorraine Iacovitti, Angelo C Lepore

Department of Neuroscience Faculty Papers

A major portion of individuals affected by traumatic spinal cord injury (SCI) experience one or more types of chronic neuropathic pain (NP), which is often intractable to currently available treatments. The availability of reliable behavioral assays in pre-clinical models of SCI-induced NP is therefore critical to assess the efficacy of new potential therapies. Commonly used assays to evaluate NP-related behavior in rodents, such as Hargreaves thermal and von Frey mechanical testing, rely on the withdrawal response to an evoked stimulus. However, other assays that test spontaneous/non-evoked NP-related behavior or supraspinal aspects of NP would be highly useful for a more …

Covid-19-Associated Cns Demyelinating Diseases, Dhanashri Miskin, Md

Department of Neuroscience Faculty Papers

Neurological manifestations of SARS-CoV-2 infection are increasingly being recognized. The most common neurologic symptoms include headache, anosmia, and dysgeusia, but patients may also develop other central nervous system (CNS) diseases.

Combination Of A Gellan Gum-Based Hydrogel With Cell Therapy For The Treatment Of Cervical Spinal Cord Injury, Eduardo D Gomes, Biswarup Ghosh, Rui Lima, Miguel Goulão, Tiago Moreira-Gomes, Joana Martins-Macedo, Mark W Urban, Megan C Wright, Jeffrey M Gimble, Nuno Sousa, Nuno A Silva, Angelo C Lepore, António J Salgado

Department of Neuroscience Faculty Papers

Cervical spinal cord trauma represents more than half of the spinal cord injury (SCI) cases worldwide. Respiratory compromise, as well as severe limb motor deficits, are among the main consequences of cervical lesions. In the present work, a Gellan Gum (GG)-based hydrogel modified with GRGDS peptide, together with adipose tissue-derived stem/stromal cells (ASCs) and olfactory ensheathing cells (OECs), was used as a therapeutic strategy after a C2 hemisection SCI in rats. Hydrogel or cells alone, and a group without treatment, were also tested. Four weeks after injury, compound muscle action potentials (CMAPs) were performed to assess functional phrenic motor neuron …

Covid-19 And Possible Links With Parkinson's Disease And Parkinsonism: From Bench To Bedside, David Sulzer, Angelo Antonini, Valentina Leta, Anna Nordvig, Richard Jay Smeyne, James E Goldman, Osama Al-Dalahmah, Luigi Zecca, Alessandro Sette, Luigi Bubacco, Olimpia Meucci, Elena Moro, Ashley S Harms, Yaqian Xu, Stanley Fahn, K Ray Chaudhuri

Department of Neuroscience Faculty Papers

This Viewpoint discusses insights from basic science and clinical perspectives on coronavirus disease 2019 (COVID-19)/severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection in the brain, with a particular focus on Parkinson's disease. Major points include that neuropathology studies have not answered the central issue of whether the virus enters central nervous system neurons, astrocytes or microglia, and the brain vascular cell types that express virus have not yet been identified. Currently, there is no clear evidence for human neuronal or astrocyte expression of angiotensin-converting enzyme 2 (ACE2), the major receptor for viral entry, but ACE2 expression may be activated by inflammation, and …

Synaptic Dysfunction Induced By Glycine-Alanine Dipeptides In C9orf72-Als/Ftd Is Rescued By Sv2 Replenishment., Brigid K Jensen, Martin H Schuldi, Kevin Mcavoy, Katelyn A Russell, Ashley Boehringer, Bridget M Curran, Karthik Krishnamurthy, Xinmei Wen, Thomas Westergard, Le Ma, Aaron R. Haeusler, Dieter Edbauer, Piera Pasinelli, Davide Trotti

Department of Neuroscience Faculty Papers

The most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) is an intronic hexanucleotide repeat expansion in the C9orf72 gene. In disease, RNA transcripts containing this expanded region undergo repeat-associated non-AUG translation to produce dipeptide repeat proteins (DPRs), which are detected in brain and spinal cord of patients and are neurotoxic both in vitro and in vivo paradigms. We reveal here a novel pathogenic mechanism for the most abundantly detected DPR in ALS/FTD autopsy tissues, poly-glycine-alanine (GA). Previously, we showed motor dysfunction in a GA mouse model without loss of motor neurons. Here, we demonstrate that mobile …

Antagonistic Regulation Of Circadian Output And Synaptic Development By Jetlag And The Dyschronic-Slowpoke Complex, Angelique Lamaze, James E.C. Jepson, Oghenerukevwe Akpoghiran, Kyunghee Koh

Department of Neuroscience Faculty Papers

Circadian output genes act downstream of the clock to promote rhythmic changes in behavior and physiology, yet their molecular and cellular functions are not well understood. Here we characterize an interaction between regulators of circadian entrainment, output, and synaptic development in Drosophila that influences clock-driven anticipatory increases in morning and evening activity. We previously showed the JETLAG (JET) E3 ubiquitin ligase resets the clock upon light exposure, whereas the PDZ protein DYSCHRONIC (DYSC) regulates circadian locomotor output and synaptic development. Surprisingly, we find that JET and DYSC antagonistically regulate synaptic development at the larval neuromuscular junction, and reduced JET activity …

Appendix 10: Neurotechnology Descriptions, Namrata Grampurohit, Phd, Otr/L

Department of Occupational Therapy Faculty Papers

Neurotechnologies Covered:

• Electrical stimulation over the surface of the arm or hand
• Electrical stimulation over the surface of the spine
• Electrical stimulation over the surface of the head
• Magnetic stimulation over the surface of the head
• Braces that are powered to amplify movements
• Brain computer interface with a cap
• Baclofen pump

Positive Surface Charge Of Glun1 N-Terminus Mediates The Direct Interaction With Ephb2 And Nmdar Mobility., Halley R. Washburn, Nan L. Xia, Wei Zhou, Yu-Ting Mao, Matthew B. Dalva

Department of Neuroscience Faculty Papers

Localization of the N-methyl-D-aspartate type glutamate receptor (NMDAR) to dendritic spines is essential for excitatory synaptic transmission and plasticity. Rather than remaining trapped at synaptic sites, NMDA receptors undergo constant cycling into and out of the postsynaptic density. Receptor movement is constrained by protein-protein interactions with both the intracellular and extracellular domains of the NMDAR. The role of extracellular interactions on the mobility of the NMDAR is poorly understood. Here we demonstrate that the positive surface charge of the hinge region of the N-terminal domain in the GluN1 subunit of the NMDAR is required to maintain NMDARs at dendritic spine …

Phosphorylation Of A K Channel By Pkc Regulates The Excitability Of Primary Sensory Neurons And Pain Signaling, Tyler D. Alexander, Lianteng Zhi, Phd, Tanziyah Muqeem, Manuel Covarrubias, Md, Phd

Phase 1

Introduction: Voltage-gated potassium channels (Kvs) play an important role in the termination of neuronal action potentials. Kv3.4 is one of many types of Kv channels, found throughout the human body – including in the axon terminals of dorsal root ganglia neurons. Kv3.4 channels are categorized as A-type currents and have prominent fast-inactivation that has been shown to be phosphorylation dependent. It is hypothesized that following spinal cord injury (SCI), Kv3.4 channels become hyperphosphorylated and their expression reduced – leading to an increase in nociceptive signaling.

Methods: We used embryonic DRG neurons, transfected with one of four types of viral …

A Crucial Role For The Protein Quality Control System In Motor Neuron Diseases., Riccardo Cristofani, Valeria Crippa, Maria Elena Cicardi, Barbara Tedesco, Veronica Ferrari, Marta Chierichetti, Elena Casarotto, Margherita Piccolella, Elio Messi, Mariarita Galbiati, Paola Rusmini, Angelo Poletti

Department of Neuroscience Faculty Papers

Motor neuron diseases (MNDs) are fatal diseases characterized by loss of motor neurons in the brain cortex, in the bulbar region, and/or in the anterior horns of the spinal cord. While generally sporadic, inherited forms linked to mutant genes encoding altered RNA/protein products have also been described. Several different mechanisms have been found altered or dysfunctional in MNDs, like the protein quality control (PQC) system. In this review, we will discuss how the PQC system is affected in two MNDs-spinal and bulbar muscular atrophy (SBMA) and amyotrophic lateral sclerosis (ALS)-and how this affects the clearance of aberrantly folded proteins, which …

Map7 Prevents Axonal Branch Retraction By Creating A Stable Microtubule Boundary To Rescue Polymerization., Stephen R. Tymanskyj, Le Ma

Farber Institute for Neuroscience Faculty Papers

Complex neural circuits are built from axonal branches that allow each neuron to connect with multiple targets. During development, maturation of nascent branches depends on stabilization of newly assembled or transported microtubules, which are thought to be regulated by microtubule-associated proteins (MAPs). However, because many known MAPs inhibit branch formation, it is not clear which MAP is responsible for regulating microtubule stability during branch development. Here, we show that MAP7, a less-well understood MAP that is localized to branch junctions, provides a key molecular mechanism to regulate microtubule stability during branch formation. In developing rodent sensory neurons of mixed sex, …

Long-Distance Axon Regeneration Promotes Recovery Of Diaphragmatic Respiratory Function After Spinal Cord Injury., Mark W. Urban, Biswarup Ghosh, Cole G. Block, Laura R. Strojny, Brittany A. Charsar, Miguel Goulão, Sreeya S. Komaravolu, George M. Smith, Megan C. Wright, Shuxin Li, Angelo C. Lepore

Farber Institute for Neuroscience Faculty Papers

Compromise in inspiratory breathing following cervical spinal cord injury (SCI) is caused by damage to descending bulbospinal axons originating in the rostral ventral respiratory group (rVRG) and consequent denervation and silencing of phrenic motor neurons (PhMNs) that directly control diaphragm activation. In a rat model of high-cervical hemisection SCI, we performed systemic administration of an antagonist peptide directed against phosphatase and tensin homolog (PTEN), a central inhibitor of neuron-intrinsic axon growth potential. PTEN antagonist peptide (PAP4) robustly restored diaphragm function, as determined with electromyography (EMG) recordings in living SCI animals. PAP4 promoted substantial, long-distance regeneration of injured rVRG axons through …

Understanding The Axonal Response To Injury By In Vivo Imaging In The Mouse Spinal Cord: A Tale Of Two Branches., Binhai Zheng, Ariana O Lorenzana, Le Ma

Department of Neuroscience Faculty Papers

Understanding the basic properties of how axons respond to injury in the mammalian central nervous system (CNS) is of fundamental value for developing strategies to promote neural repair. Axons possess complex morphologies with stereotypical branching patterns. However, current knowledge of the axonal response to injury gives little consideration to axonal branches, nor do strategies to promote axon regeneration. This article reviews evidence from in vivo spinal cord imaging that axonal branches markedly impact the degenerative and regenerative responses to injury. At a major bifurcation point, depending on whether one or both axonal branches are injured, neurons may choose either a …