Medical Neurobiology Commons^™

In Search Of The Locus Coeruleus: Guidelines For Identifying Anatomical Boundaries And Electrophysiological Properties Of The Blue Spot In Mice, Fish, Finches, And Beyond, Amelien Vreven, Gary Aston-Jones, Anthony E Pickering, Gina R Poe, Barry Waterhouse, Nelson K Totah

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Our understanding of human brain function can be greatly aided by studying analogous brain structures in other organisms. One brain structure with neurochemical and anatomical homology throughout vertebrate species is the locus coeruleus (LC), a small collection of norepinephrine (NE)-containing neurons in the brainstem that project throughout the central nervous system. The LC is involved in nearly every aspect of brain function, including arousal and learning, which has been extensively examined in rats and nonhuman primates using single-unit recordings. Recent work has expanded into putative LC single-unit electrophysiological recordings in a nonmodel species, the zebra finch. Given the importance of …

Differential Roles Of Key Brain Regions: Ventral Tegmental Area, Locus Coeruleus, Dorsal Raphe, Nucleus Accumbens, Caudate Nucleus, And Prefrontal Cortex In Regulating Response To Methylphenidate: Insights From Neuronal And Behavioral Studies In Freely Behaving Rats, Nachum Dafny, Catherine Claussen, Emilee Frazier, Yin Liu

Faculty, Staff and Student Publications

A total of 3102 neurons were recorded before and following acute and chronic methylphenidate (MPD) administration. Acute MPD exposure elicits mainly increases in neuronal and behavioral activity in dose–response characteristics. The response to chronic MPD exposure, as compared to acute 0.6, 2.5, or 10.0 mg/kg MPD administration, elicits electrophysiological and behavioral sensitization in some animals and electrophysiological and behavioral tolerance in others when the neuronal recording evaluations were performed based on the animals’ behavioral responses, or amount of locomotor activity, to chronic MPD exposure. The majority of neurons recorded from those expressing behavioral sensitization responded to chronic MPD with further …

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 …

Cns-Associated Macrophages Contribute To Intracerebral Aneurysm Pathophysiology, Martina Glavan, Ana Jelic, Damien Levard, Juhana Frösen, Sara Keränen, Bart A A Franx, Ana-Rita Bras, Estelle R Louet, Ádám Dénes, Mario Merlini, Denis Vivien, Marina Rubio

Faculty, Staff and Student Publications

Simple Summary

Vestibular schwannoma (VS), benign cranial nerve sheath tumors of the vestibulocochlear nerve, lack efficacious systemic therapies, especially if they develop in a NF2-related schwannomatosis (NF2) background. They cause hearing loss, tinnitus and balance problems. Metastasis associated in colon cancer 1 (MACC1) is a key driver of metastasis. Although MACC1 expression is associated with highly malignant tumors and VS are considered benign, both are attached to the HGF/MET signaling pathway and MACC1 is a candidate gene localized at a hearing loss-related gene locus. Therefore, it was investigated whether MACC1 might be involved in VS pathogenesis. Surprisingly, MACC1 expression …

A Novel Spatiotemporal Graph Convolutional Network Framework For Functional Connectivity Biomarkers Identification Of Alzheimer’S Disease, Ying Zhang, Le Xue, Shuoyan Zhang, Jiacheng Yang, Qi Zhang, Min Wang, Luyao Wang, Mingkai Zhang, Jiehui Jiang, Yunxia Li

Faculty, Staff and Student Publications

BACKGROUND: Functional connectivity (FC) biomarkers play a crucial role in the early diagnosis and mechanistic study of Alzheimer's disease (AD). However, the identification of effective FC biomarkers remains challenging. In this study, we introduce a novel approach, the spatiotemporal graph convolutional network (ST-GCN) combined with the gradient-based class activation mapping (Grad-CAM) model (STGC-GCAM), to effectively identify FC biomarkers for AD.

METHODS: This multi-center cross-racial retrospective study involved 2,272 participants, including 1,105 cognitively normal (CN) subjects, 790 mild cognitive impairment (MCI) individuals, and 377 AD patients. All participants underwent functional magnetic resonance imaging (fMRI) and T1-weighted MRI scans. In this study, …

Caldendrin Is A Repressor Of Piezo2 Channels And Touch Sensation In Mice, Josue A Lopez, Luis O Romero, Wai-Lin Kaung, J Wesley Maddox, Valeria Vásquez, Amy Lee

Faculty, Staff and Student Publications

The sense of touch is crucial for cognitive, emotional, and social development and relies on mechanically activated (MA) ion channels that transduce force into an electrical signal. Despite advances in the molecular characterization of these channels, the physiological factors that control their activity are poorly understood. Here, we used behavioral assays, electrophysiological recordings, and various mouse strains (males and females analyzed separately) to investigate the role of the calmodulin-like Ca2+ sensor, caldendrin, as a key regulator of MA channels and their roles in touch sensation. In mice lacking caldendrin (Cabp1 KO), heightened responses to tactile stimuli correlate with enlarged …

Sarin-Induced Neuroinflammation In Mouse Brain Is Attenuated By The Caspase Inhibitor Q-Vd-Oph, Ekta J. Shah, William C. Grunwald Jr., Teresa L. Garrett, Thomas L. Brown, David R. Cool

Neuroscience, Cell Biology & Physiology Faculty Publications

Organophosphates cause hyperstimulation of the central nervous system, leading to extended seizures, convulsions, and brain damage. Sarin is a highly toxic organophosphate nerve agent that has been employed in several terrorist attacks. The prolonged toxicity of sarin may be enhanced by the neuroinflammatory response initiated by the inflammasome, caspase involvement, and generation/release of proinflammatory cytokines. Since neurodegeneration and neuroinflammation are prevalent in sarin-exposed animals, we were interested in evaluating the capacity of quinolyl-valyl-O-methylaspartyl-[-2,6-difluorophenoxy]-methyl ketone (Q-VD-OPh), a pan caspase inhibitor to attenuate neuroinflammation following sarin exposure. To test this hypothesis, sarin-exposed C57BL/6 mice were treated with Q-VD-OPh or negative control quinolyl-valyl-O-methylglutamyl-[-2,6-difluorophenoxy]-methyl …

Increased Cysteinyl-Trna Synthetase Drives Neuroinflammation In Alzheimer’S Disease, Xiu-Hong Qi, Peng Chen, Yue-Ju Wang, Zhe-Ping Zhou, Xue-Chun Liu, Hui Fang, Chen-Wei Wang, Ji Liu, Rong-Yu Liu, Han-Kui Liu, Zhen-Xin Zhang, Jiang-Ning Zhou

Faculty, Staff and Student Publications

Background

Microglia-mediated neuroinflammation in Alzheimer’s disease (AD) is not only a response to pathophysiological events, but also plays a causative role in neurodegeneration. Cytoplasmic cysteinyl-tRNA synthetase (CARS) is considered to be a stimulant for immune responses to diseases; however, it remains unknown whether CARS is involved in the pathogenesis of AD.

Methods

Postmortem human temporal cortical tissues at different Braak stages and AD patient-derived serum samples were used to investigate the changes of CARS levels in AD by immunocytochemical staining, real-time PCR, western blotting and ELISA. After that, C57BL/6J and APP/PS1 transgenic mice and BV-2 cell line were used to …

Mechanosensory Encoding In Ex Vivo Muscle–Nerve Preparations, Stephen N. Housley, Evelyn A. Gardolinski, Paul Nardelli, J'Ana Reed, Mark M. Rich, Timothy C. Cope

Neuroscience, Cell Biology & Physiology Faculty Publications

Our objective was to evaluate an ex vivo muscle-nerve preparation used to study mechanosensory signalling by low threshold mechanosensory receptors (LTMRs). Specifically, we aimed to assess how well the ex vivo preparation represents in vivo firing behaviours of the three major LTMR subtypes of muscle primary sensory afferents, namely type Ia and II muscle spindle (MS) afferents and type Ib tendon organ afferents. Using published procedures for ex vivo study of LTMRs in mouse hindlimb muscles, we replicated earlier reports on afferent firing in response to conventional stretch paradigms applied to non-contracting, that is passive, muscle. Relative to in vivo …

Synaptic Vesicle Dynamics In Mouse Rod Bipolar Cells, Sara S Patterson, Rebecca J Girresch, Marcus A Mazzaferri, Andrea S Bordt, Wendy L Piñon-Teal, Brett D Jesse, Dinukie-Chantal W Perera, Melanie A Schlepphorst, James A Kuchenbecker, Alice Z Chuang, Jay Neitz, David W Marshak, Judith Mosinger Ogilvie

Faculty, Staff and Student Publications

Considerable progress has been made in studying the receptive fields of the most common primate retinal ganglion cell (RGC) types, such as parasol RGCs. Much less is known about the rarer primate RGC types and the circuitry that gives rise to noncanonical receptive field structures. The goal of this study was to analyze synaptic inputs to smooth monostratified RGCs to determine the origins of their complex spatial receptive fields, which contain isolated regions of high sensitivity called "hotspots." Interestingly, smooth monostratified RGCs co-stratify with the well-studied parasol RGCs and are thus constrained to receiving input from bipolar and amacrine cells …

Structures Of Channelrhodopsin Paralogs In Peptidiscs Explain Their Contrasting K+ And Na+ Selectivities, Shu Kikuta, Shin Nagayama, Sanae Hasegawa-Ishii

Faculty, Staff and Student Publications

The olfactory epithelium (OE) is directly exposed to environmental agents entering the nasal cavity, leaving OSNs prone to injury and degeneration. The causes of olfactory dysfunction are diverse and include head trauma, neurodegenerative diseases, and aging, but the main causes are chronic rhinosinusitis (CRS) and viral infections. In CRS and viral infections, reduced airflow due to local inflammation, inflammatory cytokine production, release of degranulated proteins from eosinophils, and cell injury lead to decreased olfactory function. It is well known that injury-induced loss of mature OSNs in the adult OE causes massive regeneration of new OSNs within a few months through …

Anesthetized Animal Experiments For Neuroscience Research, Shin Nagayama, Sanae Hasegawa-Ishii, Shu Kikuta

Faculty, Staff and Student Publications

Brain research has progressed with anesthetized animal experiments for a long time. Recent progress in research techniques allows us to measure neuronal activity in awake animals combined with behavioral tasks. The trends became more prominent in the last decade. This new research style triggers the paradigm shift in the research of brain science, and new insights into brain function have been revealed. It is reasonable to consider that awake animal experiments are more ideal for understanding naturalistic brain function than anesthetized ones. However, the anesthetized animal experiment still has advantages in some experiments. To take advantage of the anesthetized animal …

Dopamine, Norepinephrine And Serotonin Participate Differently In Methylphenidate Action In Concomitant Behavioral And Ventral Tegmental Area, Locus Coeruleus And Dorsal Raphe Neuronal Study In Young Rats, Cruz Reyes-Vasquez, Zachary Jones, Bin Tang, Nachum Dafny

Faculty, Staff and Student Publications

Methylphenidate (MPD), known as Ritalin, is a psychostimulant used to treat children, adults, and the elderly. MPD exerts its effects through increasing concentrations of dopamine (DA), norepinephrine (NE), and serotonin (5-HT) in the synaptic cleft. Concomitant behavioral and neuronal recording from the ventral tegmental area (VTA), locus coeruleus (LC), and from the dorsal raphe (DR) nucleus, which are the sources of DA, NE, and 5-HT to the mesocorticolimbic circuit, were investigated following acute and repetitive (chronic) saline, 0.6, 2.5, or 10.0 mg/kg MPD. Animals received daily saline or MPD administration on experimental days 1 to 6 (ED1–6), followed by a …

Enhanced Presynaptic Mitochondrial Energy Production Is Required For Memory Formation, Erica L Underwood, John B Redell, Kimberly N Hood, Mark E Maynard, Michael Hylin, M Neal Waxham, Jing Zhao, Anthony N Moore, Pramod K Dash

Faculty, Staff and Student Publications

Some of the prominent features of long-term memory formation include protein synthesis, gene expression, enhanced neurotransmitter release, increased excitability, and formation of new synapses. As these processes are critically dependent on mitochondrial function, we hypothesized that increased mitochondrial respiration and dynamics would play a prominent role in memory formation. To address this possibility, we measured mitochondrial oxygen consumption (OCR) in hippocampal tissue punches from trained and untrained animals. Our results show that context fear training significantly increased basal, ATP synthesis-linked, and maximal OCR in the Shaffer collateral-CA1 synaptic region, but not in the CA1 cell body layer. These changes were …

Cortex-Wide Neural Dynamics Predict Behavioral States And Provide A Neural Basis For Resting-State Dynamic Functional Connectivity, Somayeh Shahsavarani, David N Thibodeaux, Weihao Xu, Sharon H Kim, Fatema Lodgher, Chinwendu Nwokeabia, Morgan Cambareri, Alexis J Yagielski, Hanzhi T Zhao, Daniel A Handwerker, Javier Gonzalez-Castillo, Peter A Bandettini, Elizabeth M C Hillman

Faculty, Staff and Student Publications

Although resting-state functional magnetic resonance imaging (fMRI) studies have observed dynamically changing brain-wide networks of correlated activity, fMRI's dependence on hemodynamic signals makes results challenging to interpret. Meanwhile, emerging techniques for real-time recording of large populations of neurons have revealed compelling fluctuations in neuronal activity across the brain that are obscured by traditional trial averaging. To reconcile these observations, we use wide-field optical mapping to simultaneously record pan-cortical neuronal and hemodynamic activity in awake, spontaneously behaving mice. Some components of observed neuronal activity clearly represent sensory and motor function. However, particularly during quiet rest, strongly fluctuating patterns of activity across …

Functional Neuronal Circuits Promote Disease Progression In Cancer, Anthony C Restaino, Austin Walz, Samuel J Vermeer, Jeffrey Barr, Attila Kovács, Robin R Fettig, Daniel W Vermeer, Hunter Reavis, Caitlin S Williamson, Christopher T Lucido, Tuany Eichwald, Dalia K Omran, Euihye Jung, Lauren E Schwartz, Maria Bell, Desirae M Muirhead, Jody E Hooper, William C Spanos, Ronny Drapkin, Sebastien Talbot, Paola D Vermeer

Faculty, Staff and Student Publications

The molecular and functional contributions of intratumoral nerves to disease remain largely unknown. We localized synaptic markers within tumors suggesting that these nerves form functional connections. Consistent with this, electrophysiological analysis shows that malignancies harbor significantly higher electrical activity than benign disease or normal tissues. We also demonstrate pharmacologic silencing of tumoral electrical activity. Tumors implanted in transgenic animals lacking nociceptor neurons show reduced electrical activity. These data suggest that intratumoral nerves remain functional at the tumor bed. Immunohistochemical staining demonstrates the presence of the neuropeptide, Substance P (SP), within the tumor space. We show that tumor cells express the …

The Alzheimer’S Disease Risk Factor Inpp5d Restricts Neuroprotective Microglial Responses In Amyloid Beta-Mediated Pathology, Mary Claire Tuohy, Elizabeth M C Hillman, Randolph Marshall, Dritan Agalliu

Faculty, Staff and Student Publications

Stroke is a devastating cause of global morbidity and mortality. Ischemic brain injury triggers a profound local and systemic immune response that participates in stroke pathophysiology. In turn, this immune response has emerged as a potential therapeutic target. In order to maximize its therapeutic potential, it is critical to understand how the immune response to ischemic brain injury is affected by age - the strongest non-modifiable risk factor for stroke. The development of multi-omics and single-cell technologies has provided a more comprehensive characterization of transcriptional and cellular changes that occur during aging. In this review, we summarize recent advances in …

Positioning The Brainstem Within The Neural Network Of Threat Prediction, Xu O Zhang, Fabricio H Do Monte

Faculty, Staff and Student Publications

In a recent study, Strickland and McDannald dissected the role of brainstem networks in threat prediction. Using probabilistic threat discrimination in rats, the authors demonstrated that brainstem neurons estimate threat probability and generate positive aversive prediction errors after unexpected outcomes. Their findings suggest that, beyond organizing defensive behaviors, brainstem neurons are involved in threat prediction computations.

G Protein-Coupled Receptor Kinase-2 (Grk-2) Controls Exploration Through Neuropeptide Signaling In Caenorhabditis Elegans, Kristen Davis, Christo Mitchell, Olivia Weissenfels, Jihong Bai, David M. Raizen, Michael Ailion, Irini Topalidou

Department of Neuroscience Faculty Papers

Animals alter their behavior in manners that depend on environmental conditions as well as their developmental and metabolic states. For example, C. elegans is quiescent during larval molts or during conditions of satiety. By contrast, worms enter an exploration state when removed from food. Sensory perception influences movement quiescence (defined as a lack of body movement), as well as the expression of additional locomotor states in C. elegans that are associated with increased or reduced locomotion activity, such as roaming (exploration behavior) and dwelling (local search). Here we find that movement quiescence is enhanced, and exploration behavior is reduced in …

Excessive Mechanotransduction In Sensory Neurons Causes Joint Contractures, Shang Ma, Adrienne E Dubin, Luis O Romero, Meaghan Loud, Alexandra Salazar, Sarah Chu, Nikola Klier, Sameer Masri, Yunxiao Zhang, Yu Wang, Alex T Chesler, Katherine A Wilkinson, Valeria Vásquez, Kara L Marshall, Ardem Patapoutian

Faculty, Staff and Student Publications

Distal arthrogryposis (DA) is a collection of rare disorders that are characterized by congenital joint contractures. Most DA mutations are in muscle- and joint-related genes, and the anatomical defects originate cell-autonomously within the musculoskeletal system. However, gain-of-function mutations in PIEZO2, a principal mechanosensor in somatosensation, cause DA subtype 5 (DA5) through unknown mechanisms. We show that expression of a gain-of-function PIEZO2 mutation in proprioceptive sensory neurons that mainly innervate muscle spindles and tendons is sufficient to induce DA5-like phenotypes in mice. Overactive PIEZO2 causes anatomical defects through increased activity within the peripheral nervous system during postnatal development. Furthermore, botulinum toxin …

Trogocytosis Of Neurons And Glial Cells By Microglia In A Healthy Adult Macaque Retina, Megan Goyal, Andrea S Bordt, Jay Neitz, David W Marshak

Faculty, Staff and Student Publications

Microglial cells are the primary resident immune cells in the retina. In healthy adults, they are ramified; that is, they have extensive processes that move continually. In adult retinas, microglia maintain the normal structure and function of neurons and other glial cells, but the mechanism underlying this process is not well-understood. In the mouse hippocampus, microglia engulf small pieces of axons and presynaptic terminals via a process called trogocytosis. Here we report that microglia in the adult macaque retina also engulf pieces of neurons and glial cells, but not at sites of synapses. We analyzed microglia in a volume of …

Nasal Accumulation And Metabolism Of Δ9-Tetrahydrocannabinol Following Aerosol (‘Vaping’) Administration In An Adolescent Rat Model, Alexa Torrens, Christina M Ruiz, Maricela X Martinez, Alex Mabou Tagne, Pritam Roy, Dakota Grimes, Faizy Ahmed, Valeria Lallai, Victoria Inshishian, Malia Bautista, Yen-Chu Chen, Marilyn A. Huestis, Aditi Das, Christie D Fowler, Stephen V Mahler, Daniele Piomelli

Institute of Emerging Health Professions Faculty Papers

Passive aerosol exposure to Δ9-tetrahydrocannabinol (THC) in laboratory animals results in faster onset of action and less extensive liver metabolism compared to most other administration routes and might thus provide an ecologically relevant model of human cannabis inhalation. Previous studies have, however, overlooked the possibility that rodents, as obligate nose breathers, may accumulate aerosolized THC in the nasal cavity, from where the drug might directly diffuse to the brain. To test this, we administered THC (ten 5-s puffs of 100 mg/mL of THC) to adolescent (31-day-old) Sprague-Dawley rats of both sexes. We used liquid chromatography/tandem mass spectrometry to quantify the …

Synaptic Development In Diverse Olfactory Neuron Classes Uses Distinct Temporal And Activity-Related Programs, Michael A. Aimino, Alison T. Depew, Lucas Restrepo, Timothy J. Mosca

Farber Institute for Neuroscience Faculty Papers

Developing neurons must meet core molecular, cellular, and temporal requirements to ensure the correct formation of synapses, resulting in functional circuits. However, because of the vast diversity in neuronal class and function, it is unclear whether or not all neurons use the same organizational mechanisms to form synaptic connections and achieve functional and morphologic maturation. Moreover, it remains unknown whether neurons united in a common goal and comprising the same sensory circuit develop on similar timescales and use identical molecular approaches to ensure the formation of the correct number of synapses. To begin to answer these questions, we took advantage …

Characterization Of A Bioactive Peptide T14 In The Human And Rodent Substantia Nigra: Implications For Neurodegenerative Disease, Susan Adele Greenfield, Giovanni Ferrati, Clive W Coen, Auguste Vadisiute, Zoltan Molnár, Sara Garcia-Rates, Sally Frautschy, Gregory M Cole

Faculty, Staff and Student Publications

The substantia nigra is generally considered to show significant cell loss not only in Parkinson's but also in Alzheimer's disease, conditions that share several neuropathological traits. An interesting feature of this nucleus is that the pars compacta dopaminergic neurons contain acetylcholinesterase (AChE). Independent of its enzymatic role, this protein is released from pars reticulata dendrites, with effects that have been observed in vitro, ex vivo and in vivo. The part of the molecule responsible for these actions has been identified as a 14-mer peptide, T14, cleaved from the AChE C-terminus and acting at an allosteric site on alpha-7 nicotinic receptors, …

Rapid Reconstruction Of Neural Circuits Using Tissue Expansion And Light Sheet Microscopy, Joshua L Lillvis, Hideo Otsuna, Xiaoyu Ding, Igor Pisarev, Takashi Kawase, Jennifer Colonell, Konrad Rokicki, Cristian Goina, Ruixuan Gao, Amy Hu, Kaiyu Wang, John Bogovic, Daniel E Milkie, Linus Meienberg, Brett D Mensh, Edward S Boyden, Stephan Saalfeld, Paul W Tillberg, Barry J Dickson

Faculty, Staff and Student Publications

Brain function is mediated by the physiological coordination of a vast, intricately connected network of molecular and cellular components. The physiological properties of neural network components can be quantified with high throughput. The ability to assess many animals per study has been critical in relating physiological properties to behavior. By contrast, the synaptic structure of neural circuits is presently quantifiable only with low throughput. This low throughput hampers efforts to understand how variations in network structure relate to variations in behavior. For neuroanatomical reconstruction, there is a methodological gulf between electron microscopic (EM) methods, which yield dense connectomes at considerable …

Synaptic Origins Of The Complex Receptive Field Structure In Primate Smooth Monostratified Retinal Ganglion Cells, Andrea S Bordt, Sara S Patterson, James A Kuchenbecker, Marcus A Mazzaferri, Joel N Yearick, Emma R Yang, Judith Mosinger Ogilvie, Jay Neitz, David W Marshak

Faculty, Staff and Student Publications

Ganglion cells are the projection neurons of the retina. Intrinsically photosensitive retinal ganglion cells (ipRGCs) express the photopigment melanopsin and also receive input from rods and cones via bipolar cells and amacrine cells. In primates, multiple types of ipRGCs have been identified. The ipRGCs with somas in the ganglion cell layer have been studied extensively, but less is known about those with somas in the inner nuclear layer, the "displaced" cells. To investigate their synaptic inputs, three sets of horizontal, ultrathin sections through central macaque retina were collected using serial block-face scanning electron microscopy. One displaced ipRGC received nearly all …

Hepatic Circadian And Differentiation Factors Control Liver Susceptibility For Fatty Liver Disease And Tumorigenesis, Baharan Fekry, Aleix Ribas-Latre, Rachel Van Drunen, Rafael Bravo Santos, Samay Shivshankar, Yulin Dai, Zhongming Zhao, Seung-Hee Yoo, Zheng Chen, Kai Sun, Frances M Sladek, Mamoun Younes, Kristin Eckel-Mahan

Faculty, Staff and Student Publications

Hepatocellular carcinoma (HCC) is a leading cause of cancer deaths, and the most common primary liver malignancy to present in the clinic. With the exception of liver transplant, treatment options for advanced HCC are limited, but improved tumor stratification could open the door to new treatment options. Previously, we demonstrated that the circadian regulator Aryl Hydrocarbon-Like Receptor Like 1 (ARNTL, or Bmal1) and the liver-enriched nuclear factor 4 alpha (HNF4α) are robustly co-expressed in healthy liver but incompatible in the context of HCC. Faulty circadian expression of HNF4α- either by isoform switching, or loss of expression- results in an increased …

Computational Analysis Of Memory Consolidation Following Inhibitory Avoidance (Ia) Training In Adult And Infant Rats: Critical Roles Of Camkiia And Mecp2, Yili Zhang, Paul Smolen, Cristina M Alberini, Douglas A Baxter, John H Byrne

Faculty, Staff and Student Publications

Key features of long-term memory (LTM), such as its stability and persistence, are acquired during processes collectively referred to as consolidation. The dynamics of biological changes during consolidation are complex. In adult rodents, consolidation exhibits distinct periods during which the engram is more or less resistant to disruption. Moreover, the ability to consolidate memories differs during developmental periods. Although the molecular mechanisms underlying consolidation are poorly understood, the initial stages rely on interacting signaling pathways that regulate gene expression, including brain-derived neurotrophic factor (BDNF) and Ca²⁺/calmodulin-dependent protein kinase II α (CaMKIIα) dependent feedback loops. We investigated the ways …

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 …

Oleic Acid Is An Endogenous Ligand Of Tlx/Nr2e1 That Triggers Hippocampal Neurogenesis, Prasanna Kandel, Fatih Semerci, Rachana Mishra, William Choi, Aleksandar Bajic, Dodge Baluya, Lihua Ma, Kevin Chen, Austin C Cao, Tipwarin Phongmekhin, Nick Matinyan, Alba Jiménez-Panizo, Srinivas Chamakuri, Idris O Raji, Lyra Chang, Pablo Fuentes-Prior, Kevin R Mackenzie, Caroline L Benn, Eva Estébanez-Perpiñá, Koen Venken, David D Moore, Damian W Young, Mirjana Maletic-Savatic

Faculty, Staff and Students Publications

Neural stem cells, the source of newborn neurons in the adult hippocampus, are intimately involved in learning and memory, mood, and stress response. Despite considerable progress in understanding the biology of neural stem cells and neurogenesis, regulating the neural stem cell population precisely has remained elusive because we have lacked the specific targets to stimulate their proliferation and neurogenesis. The orphan nuclear receptor TLX/NR2E1 governs neural stem and progenitor cell self-renewal and proliferation, but the precise mechanism by which it accomplishes this is not well understood because its endogenous ligand is not known. Here, we identify oleic acid (18:1ω9 monounsaturated …