Neuroscience and Neurobiology Commons^™

Type 2 Neural Progenitor Cell Activation Drives Reactive Neurogenesis After Binge-Like Alcohol Exposure In Adolescent Male Rats, Chelsea Rhea Geil Nickell, Hui Peng, Dayna M. Hayes, Kevin Y. Chen, Justin A. Mcclain, Kimberly Nixon

Pharmaceutical Sciences Faculty Publications

Excessive alcohol consumption during adolescence remains a significant health concern as alcohol drinking during adolescence increases the likelihood of an alcohol use disorder in adulthood by fourfold. Binge drinking in adolescence is a particular problem as binge-pattern consumption is the biggest predictor of neurodegeneration from alcohol and adolescents are particularly susceptible to the damaging effects of alcohol. The adolescent hippocampus, in particular, is highly susceptible to alcohol-induced structural and functional effects, including volume and neuron loss. However, hippocampal structure and function may recover with abstinence and, like in adults, a reactive burst in hippocampal neurogenesis in abstinence may contribute to …

Methylglyoxal Requires Ac1 And Trpa1 To Produce Pain And Spinal Neuron Activation, Ryan B. Griggs, Don E. Laird, Renee R. Donahue, Weisi Fu, Bradley K. Taylor

Physiology Faculty Publications

Methylglyoxal (MG) is a metabolite of glucose that may contribute to peripheral neuropathy and pain in diabetic patients. MG increases intracellular calcium in sensory neurons and produces behavioral nociception via the cation channel transient receptor potential ankyrin 1 (TRPA1). However, rigorous characterization of an animal model of methylglyoxal-evoked pain is needed, including testing whether methylglyoxal promotes negative pain affect. Furthermore, it remains unknown whether methylglyoxal is sufficient to activate neurons in the spinal cord dorsal horn, whether this requires TRPA1, and if the calcium-sensitive adenylyl cyclase 1 isoform (AC1) contributes to MG-evoked pain. We administered intraplantar methylglyoxal and then evaluated …

Physical Aggressiveness And Gray Matter Deficits In Ventromedial Prefrontal Cortex, David S. Chester, Donald R. Lynam, Richard Milich, C. Nathan Dewall

Psychology Faculty Publications

What causes individuals to hurt others? Since the famous case of Phineas Gage, lesions of the ventromedial prefrontal cortex (VMPFC) have been reliably linked to physically aggressive behavior. However, it is unclear whether naturally-occurring deficits in VMPFC, among normal individuals, might have widespread consequences for aggression. Using voxel based morphometry, we regressed gray matter density from the brains of 138 normal female and male adults onto their dispositional levels of physical aggression, verbal aggression, and sex, simultaneously. Physical, but not verbal, aggression was associated with reduced gray matter volume in the VMPFC and to a lesser extent, frontopolar cortex. Participants …

A Deafness Mechanism Of Digenic Cx26 (Gjb2) And Cx30 (Gjb6) Mutations: Reduction Of Endocochlear Potential By Impairment Of Heterogeneous Gap Junctional Function In The Cochlear Lateral Wall, Ling Mei, Jin Chen, Liang Zong, Yan Zhu, Chun Liang, Raleigh O. Jones, Hong-Bo Zhao

Otolaryngology--Head & Neck Surgery Faculty Publications

Digenic Connexin26 (Cx26, GJB2) and Cx30 (GJB6) heterozygous mutations are the second most frequent cause of recessive deafness in humans. However, the underlying deafness mechanism remains unclear. In this study, we created different double Cx26 and Cx30 heterozygous (Cx26^+/−/Cx30^+/−) mouse models to investigate the underlying pathological changes and deafness mechanism. We found that double Cx26^+/−/Cx30^+/− heterozygous mice had hearing loss. Endocochlear potential (EP), which is a driving force for hair cells producing auditory receptor current, was reduced. However, unlike Cx26 homozygous knockout (Cx26^−/−) mice, the cochlea in Cx26 …

A Customized Quantitative Pcr Microrna Panel Provides A Technically Robust Context For Studying Neurodegenerative Disease Biomarkers And Indicates A High Correlation Between Cerebrospinal Fluid And Choroid Plexus Microrna Expression, Wang-Xia Wang, David W. Fardo, Gregory A. Jicha, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

MicroRNA (miRNA) expression varies in association with different tissue types and in diseases. Having been found in body fluids including blood and cerebrospinal fluid (CSF), miRNAs constitute potential biomarkers. CSF miRNAs have been proposed as biomarkers for neurodegenerative diseases; however, there is a lack of consensus about the best candidate miRNA biomarkers and there has been variability in results from different research centers, perhaps due to technical factors. Here, we sought to optimize technical parameters for CSF miRNA studies. We examined different RNA isolation methods and performed miRNA expression profiling with TaqMan® miRNA Arrays. More specifically, we developed a customized …

Complement 3a Receptor In Dorsal Horn Microglia Mediates Pronociceptive Neuropeptide Signaling, Suzanne Doolen, Jennifer Cook, Maureen Riedl, Kelley Kitto, Shinichi Kohsaka, Christopher N. Honda, Carolyn A. Fairbanks, Bradley K. Taylor, Lucy Vulchanova

Physiology Faculty Publications

The complement 3a receptor (C3aR1) participates in microglial signaling under pathological conditions and was recently shown to be activated by the neuropeptide TLQP‐21. We previously demonstrated that TLQP‐21 elicits hyperalgesia and contributes to nerve injury‐induced hypersensitivity through an unknown mechanism in the spinal cord. Here we determined that this mechanism requires C3aR1 and that microglia are the cellular target for TLQP‐21. We propose a novel neuroimmune signaling pathway involving TLQP‐21‐induced activation of microglial C3aR1 that then contributes to spinal neuroplasticity and neuropathic pain. This unique dual‐ligand activation of C3aR1 by a neuropeptide (TLQP‐21) and an immune mediator (C3a) represents a …

Binge Alcohol Exposure Transiently Changes The Endocannabinoid System: A Potential Target To Prevent Alcohol-Induced Neurodegeneration, Daniel J. Liput, James R. Pauly, Audra L. Stinchcomb, Kimberly Nixon

Pharmaceutical Sciences Faculty Publications

Excessive alcohol consumption leads to neurodegeneration, which contributes to cognitive decline that is associated with alcohol use disorders (AUDs). The endocannabinoid system has been implicated in the development of AUDs, but little is known about how the neurotoxic effects of alcohol impact the endocannabinoid system. Therefore, the current study investigated the effects of neurotoxic, binge-like alcohol exposure on components of the endocannabinoid system and related N-acylethanolamines (NAEs), and then evaluated the efficacy of fatty acid amide hydrolase (FAAH) inhibition on attenuating alcohol-induced neurodegeneration. Male rats were administered alcohol according to a binge model, which resulted in a transient decrease in …

Novel Calcium-Related Targets Of Insulin In Hippocampal Neurons, Shaniya Maimaiti, Hilaree N. Frazier, Katie L. Anderson, Adam O. Ghoweri, Lawrence D. Brewer, Nada M. Porter, Olivier Thibault

Pharmacology and Nutritional Sciences Faculty Publications

Both insulin signaling disruption and Ca²⁺ dysregulation are closely related to memory loss during aging and increase the vulnerability to Alzheimer's disease (AD). In hippocampal neurons, aging-related changes in calcium regulatory pathways have been shown to lead to higher intracellular calcium levels and an increase in the Ca²⁺-dependent afterhyperpolarization (AHP), which is associated with cognitive decline. Recent studies suggest that insulin reduces the Ca²⁺-dependent AHP. Given the sensitivity of neurons to insulin and evidence that brain insulin signaling is reduced with age, insulin-mediated alterations in calcium homeostasis may underlie the beneficial actions of insulin in …

P2x2 Dominant Deafness Mutations Have No Negative Effect On Wild-Type Isoform: Implications For Functional Rescue And In Deafness Mechanism, Yan Zhu, Juline Beudez, Ning Yu, Thomas Grutter, Hong-Bo Zhao

Otolaryngology--Head & Neck Surgery Faculty Publications

The P2X2 receptor is an ATP-gated ion channel, assembled by three subunits. Recently, it has been found that heterozygous mutations of P2X2 V60L and G353R can cause autosomal dominant nonsyndromic hearing loss. However, the underlying mechanism remains unclear. The fact that heterozygous mutations cause deafness suggests that the mutations may have dominant-negative effect (DNE) on wild-type (WT) P2X2 isoforms and/or other partners leading to hearing loss. In this study, the effect of these dominant deafness P2X2 mutations on WT P2X2 was investigated. We found that sole transfection of both V60L and G353R deafness mutants could efficiently target to the plasma …

Low Arousal Positive Emotional Stimuli Attenuate Aberrant Working Memory Processing In Persons With Mild Cognitive Impairment, Lucas S. Broster, Shonna L. Jenkins, Sarah D. Holmes, Gregory A. Jicha, Yang Jiang

Behavioral Science Faculty Publications

Emotional enhancement effects on memory have been reported to mitigate the pathophysiology of Alzheimer’s disease (AD). However, relative to their manifestation in persons without pathologic aging, these effects may be reduced in magnitude or even deleterious, especially in tasks that more closely model ecologic memory performance. Based upon a synthesis of such reports, we hypothesized that in persons with AD low arousal positive stimuli would evoke relatively intact emotional enhancement effects, but that high arousal negative stimuli would evoke disordered emotional enhancement effects. To assess this, participants with and without mild cognitive impairment (MCI) presumed to be due to AD …

Dynamic Range Of Frontoparietal Functional Modulation Is Associated With Working Memory Capacity Limitations In Older Adults, Jonathan G. Hakun, Nathan F. Johnson

Physical Therapy Faculty Publications

Older adults tend to over-activate regions throughout frontoparietal cortices and exhibit a reduced range of functional modulation during WM task performance compared to younger adults. While recent evidence suggests that reduced functional modulation is associated with poorer task performance, it remains unclear whether reduced range of modulation is indicative of general WM capacity-limitations. In the current study, we examined whether the range of functional modulation observed over multiple levels of WM task difficulty (N-Back) predicts in-scanner task performance and out-of-scanner psychometric estimates of WM capacity. Within our sample (60–77 years of age), age was negatively associated with frontoparietal modulation range. …

Chronic Traumatic Encephalopathy-Integration Of Canonical Traumatic Brain Injury Secondary Injury Mechanisms With Tau Pathology, Jacqueline R. Kulbe, Edward D. Hall

Spinal Cord and Brain Injury Research Center Faculty Publications

In recent years, a new neurodegenerative tauopathy labeled Chronic Traumatic Encephalopathy (CTE), has been identified that is believed to be primarily a sequela of repeated mild traumatic brain injury (TBI), often referred to as concussion, that occurs in athletes participating in contact sports (e.g. boxing, football, football, rugby, soccer, ice hockey) or in military combatants, especially after blast-induced injuries. Since the identification of CTE, and its neuropathological finding of deposits of hyperphosphorylated tau protein, mechanistic attention has been on lumping the disorder together with various other non-traumatic neurodegenerative tauopathies. Indeed, brains from suspected CTE cases that have come to autopsy …

The Effect Of Co2, Intracellular Ph And Extracellular Ph On Mechanosensory Proprioceptor Responses In Crayfish And Crab, Viresh Dayaram, Cole A. Malloy, Sarah Martha, Brenda Alvarez, Ikenna Chukwudolue, Nadera Dabbain, Dlovan D.Mahmood, Slavina Goleva, Tori Hickey, Angel Ho, Molly King, Paige Kington, Matthew Mattingly, Samuel Potter, Landon Simpson, Amanda Spence, Henry Uradu, Jacob Van Doorn, Dlovan Faiq, Robin L. Cooper

Biology Faculty Publications

Proprioceptive neurons monitor the movements of limbs and joints to transduce the movements into electrical signals. These neurons function similarly in species from arthropods to humans. These neurons can be compromised in disease states and in adverse environmental conditions such as with changes in external and internal pH. We used two model preparations (the crayfish muscle receptor organ and a chordotonal organ in the limb of a crab) to characterize the responses of these proprioceptors to external and internal pH changes as well as raised CO₂. The results demonstrate the proprioceptive organs are not highly sensitive to changes …

Pattern Discovery In Brain Imaging Genetics Via Scca Modeling With A Generic Non-Convex Penalty, Lei Du, Kefei Liu, Xiaohui Yao, Jingwen Yan, Shannon L. Risacher, Junwei Han, Lei Guo, Andrew J. Saykin, Li Shen, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, John Morris, Leslie M. Shaw, Zaven Khachaturian, Greg Sorensen, Maria Carrillo, Lew Kuller, Marc Raichle, Steven Paul, Peter Davies, Howard Fillit, Franz Hefti, David Holtzman, Charles D. Smith, Gregory Jicha, Peter A. Hardy, Partha Sinha, Elizabeth Oates, Gary Conrad

Neurology Faculty Publications

Brain imaging genetics intends to uncover associations between genetic markers and neuroimaging quantitative traits. Sparse canonical correlation analysis (SCCA) can discover bi-multivariate associations and select relevant features, and is becoming popular in imaging genetic studies. The L1-norm function is not only convex, but also singular at the origin, which is a necessary condition for sparsity. Thus most SCCA methods impose ℓ₁-norm onto the individual feature or the structure level of features to pursuit corresponding sparsity. However, the ℓ₁-norm penalty over-penalizes large coefficients and may incurs estimation bias. A number of non-convex penalties are proposed to reduce …

A Latent Propriospinal Network Can Restore Diaphragm Function After High Cervical Spinal Cord Injury, Jared M. Cregg, Kevin A. Chu, Lydia E. Hager, Rachel S. J. Maggard, Daimen R. Stoltz, Michaela Edmond, Warren J. Alilain, Polyxeni Philippidou, Lynn T. Landmesser, Jerry Silver

Spinal Cord and Brain Injury Research Center Faculty Publications

Spinal cord injury (SCI) above cervical level 4 disrupts descending axons from the medulla that innervate phrenic motor neurons, causing permanent paralysis of the diaphragm. Using an ex vivo preparation in neonatal mice, we have identified an excitatory spinal network that can direct phrenic motor bursting in the absence of medullary input. After complete cervical SCI, blockade of fast inhibitory synaptic transmission caused spontaneous, bilaterally coordinated phrenic bursting. Here, spinal cord glutamatergic neurons were both sufficient and necessary for the induction of phrenic bursts. Direct stimulation of phrenic motor neurons was insufficient to evoke burst activity. Transection and pharmacological manipulations …

Single-Base Resolution Mapping Of 5-Hydroxymethylcytosine Modifications In Hippocampus Of Alzheimer's Disease Subjects, Elizabeth M. Ellison, Melissa A. Bradley-Whitman, Mark A. Lovell

Chemistry Faculty Publications

Epigenetic modifications to cytosine have been shown to regulate transcription in cancer, embryonic development, and recently neurodegeneration. While cytosine methylation studies are now common in neurodegenerative research, hydroxymethylation studies are rare, particularly genome-wide mapping studies. As an initial study to analyze 5-hydroxymethylcytosine (5-hmC) in the Alzheimer’s disease (AD) genome, reduced representation hydroxymethylation profiling (RRHP) was used to analyze more than 2 million sites of possible modification in hippocampal DNA of sporadic AD and normal control subjects. Genes with differentially hydroxymethylated regions were filtered based on previously published microarray data for altered gene expression in hippocampal DNA of AD subjects. Our …

Targeting Mitochondrial Dysfunction In Cns Injury Using Methylene Blue; Still A Magic Bullet?, Hemendra J. Vekaria, Lora Talley Watts, Ai-Ling Lin, Patrick G. Sullivan

Spinal Cord and Brain Injury Research Center Faculty Publications

Complex, multi-factorial secondary injury cascades are initiated following traumatic brain injury, which makes this a difficult disease to treat. The secondary injury cascades following the primary mechanical tissue damage, are likely where effective therapeutic interventions may be targeted. One promising therapeutic target following brain injury are mitochondria. Mitochondria are complex organelles found within the cell, which act as powerhouses within all cells by supplying ATP. These organelles are also necessary for calcium cycling, redox signaling and play a major role in the initiation of cell death pathways. When mitochondria become dysfunctional, there is a tendency for the cell to loose …

Clinically Silent Alzheimer's And Vascular Pathologies Influence Brain Networks Supporting Executive Function In Healthy Older Adults, Brian T. Gold, Christopher A. Brown, Jonathan G. Hakun, Leslie M. Shaw, John Q. Trojanowski, Charles D. Smith

Neuroscience Faculty Publications

Aging is associated with declines in executive function. We examined how executive functional brain systems are influenced by clinically silent Alzheimer’s disease (AD) pathology and cerebral white matter hyperintensities (WMHs). Twenty-nine younger adults and thirty-four cognitively normal older adults completed a working memory paradigm while functional magnetic resonance imaging (fMRI) was performed. Older adults further underwent lumbar cerebrospinal fluid (CSF) draw for assessment of AD pathology and FLAIR imaging for assessment of WMHs. Accurate working memory performance in both age groups was associated with high fronto-visual functional connectivity (fC). However, in older adults, higher expression of fronto-visual fC was linked …

Acute Treatment With Doxorubicin Affects Glutamate Neurotransmission In The Mouse Frontal Cortex And Hippocampus, Theresa Currier Thomas, Joshua A. Beitchman, Francois Pomerleau, Teresa Noel, Paiboon Jungsuwadee, D. Allan Butterfield, Daret K. St. Clair, Mary Vore, Greg A. Gerhardt

Spinal Cord and Brain Injury Research Center Faculty Publications

Doxorubicin (DOX) is a potent chemotherapeutic agent known to cause acute and long-term cognitive impairments in cancer patients. Cognitive function is presumed to be primarily mediated by neuronal circuitry in the frontal cortex (FC) and hippocampus, where glutamate is the primary excitatory neurotransmitter. Mice treated with DOX (25 mg/kg i.p.) were subjected to in vivo recordings under urethane anesthesia at 24h post-DOX injection or 5 consecutive days of cognitive testing (Morris Water Maze; MWM). Using novel glutamate-selective microelectrode arrays, amperometric recordings measured parameters of extracellular glutamate clearance and potassium-evoked release of glutamate within the medial FC and dentate gyrus (DG) …

Systems Biology Approach To Late-Onset Alzheimer's Disease Genome-Wide Association Study Identifies Novel Candidate Genes Validated Using Brain Expression Data And Caenorhabditis Elegans Experiments, Shubhabrata Mukherjee, Joshua C. Russell, Daniel T. Carr, Jeremy D. Burgess, Mariet Allen, Daniel J. Serie, Kevin L. Boehme, John S. K. Kauwe, Adam C. Naj, David W. Fardo, Dennis W. Dickson, Thomas J. Montine, Nilufer Ertekin-Taner, Matt R. Kaeberlein, Paul K. Crane

Biostatistics Faculty Publications

Introduction—We sought to determine whether a systems biology approach may identify novel late-onset Alzheimer's disease (LOAD) loci.

Methods—We performed gene-wide association analyses and integrated results with human protein-protein interaction data using network analyses. We performed functional validation on novel genes using a transgenic Caenorhabditis elegans Aβ proteotoxicity model and evaluated novel genes using brain expression data from people with LOAD and other neurodegenerative conditions.

Results—We identified 13 novel candidate LOAD genes outside chromosome 19. Of those, RNA interference knockdowns of the C. elegans orthologs of UBC, NDUFS3, EGR1, and ATP5H were associated with Aβ …

Age Drives Distortion Of Brain Metabolic, Vascular And Cognitive Functions, And The Gut Microbiome, Jared D. Hoffman, Ishita Parikh, Stefan J. Green, George Chlipala, Robert P. Mohney, Mignon Keaton, Bjoern Bauer, Anika M. S. Hartz, Ai-Ling Lin

Sanders-Brown Center on Aging Faculty Publications

Advancing age is the top risk factor for the development of neurodegenerative disorders, including Alzheimer’s disease (AD). However, the contribution of aging processes to AD etiology remains unclear. Emerging evidence shows that reduced brain metabolic and vascular functions occur decades before the onset of cognitive impairments, and these reductions are highly associated with low-grade, chronic inflammation developed in the brain over time. Interestingly, recent findings suggest that the gut microbiota may also play a critical role in modulating immune responses in the brain via the brain-gut axis. In this study, our goal was to identify associations between deleterious changes in …

Reduced Ability Of Calcitriol To Promote Augmented Dopamine Release In The Lesioned Striatum Of Aged Rats, Wayne A. Cass, Laura E. Peters

Neuroscience Faculty Publications

Parkinson’s disease (PD) is a progressive and debilitating neurodegenerative disorder that affects over one million people in the United States. Previous studies, carried out in young adult rats, have shown that calcitriol, the active metabolite of vitamin D, can be neuroprotective in 6-hydroxydopamine (6-OHDA) models of PD. However, as PD usually affects older individuals, the ability of calcitriol to promote dopaminergic recovery was examined in lesioned young adult (4 month old), middle-aged (14 month old) and aged (22 month old) rats. Animals were given a single injection of 12 μg 6-OHDA into the right striatum. Four weeks later they were …

Thiamine Deficiency And Neurodegeneration: The Interplay Among Oxidative Stress, Endoplasmic Reticulum Stress, And Autophagy, Dexiang Liu, Zunji Ke, Jia Luo

Pharmacology and Nutritional Sciences Faculty Publications

Thiamine (vitamin B1) is an essential nutrient and indispensable for normal growth and development of the organism due to its multilateral participation in key biochemical and physiological processes. Humans must obtain thiamine from their diet since it is synthesized only in bacteria, fungi, and plants. Thiamine deficiency (TD) can result from inadequate intake, increased requirement, excessive deletion, and chronic alcohol consumption. TD affects multiple organ systems, including the cardiovascular, muscular, gastrointestinal, and central and peripheral nervous systems. In the brain, TD causes a cascade of events including mild impairment of oxidative metabolism, neuroinflammation, and neurodegeneration, which are commonly observed in …

Challenges And Considerations Related To Studying Dementia In Blacks/African Americans, Eseosa T. Ighodaro, Peter T. Nelson, Walter A. Kukull, Frederick A. Schmitt, Erin L. Abner, Allison M. Caban-Holt, Shoshana H. Bardach, Derrick C. Hord, Crystal M. Glover, Gregory A. Jicha, Linda J. Van Eldik, Alexander X. Byrd, Anita Fernander

Neuroscience Faculty Publications

Blacks/African Americans have been reported to be ~2–4 times more likely to develop clinical Alzheimer’s disease (AD) compared to Whites. Unfortunately, study design challenges (e.g., recruitment bias), racism, mistrust of healthcare providers and biomedical researchers, confounders related to socioeconomic status, and other sources of bias are often ignored when interpreting differences in human subjects categorized by race. Failure to account for these factors can lead to misinterpretation of results, reification of race as biology, discrimination, and missed or delayed diagnoses. Here we provide a selected historical background, discuss challenges, present opportunities, and suggest considerations for studying health outcomes among racial/ethnic …

Investigation Of The Safety Of Focused Ultrasound-Induced Blood-Brain Barrier Opening In A Natural Canine Model Of Aging, Meaghan Anne O'Reilly, Ryan Matthew Jones, Edward Barrett, Anthony P. Schwab, Elizabeth Head, Kullervo Hynynen

Sanders-Brown Center on Aging Faculty Publications

Rationale: Ultrasound-mediated opening of the Blood-Brain Barrier(BBB) has shown exciting potential for the treatment of Alzheimer's disease(AD). Studies in transgenic mouse models have shown that this approach can reduce plaque pathology and improve spatial memory. Before clinical translation can occur the safety of the method needs to be tested in a larger brain that allows lower frequencies be used to treat larger tissue volumes, simulating clinical situations. Here we investigate the safety of opening the BBB in half of the brain in a large aged animal model with naturally occurring amyloid deposits.

Methods: Aged dogs naturally accumulate plaques and show …

Interleukin-6 (Il-6) Rs1800796 And Cyclin Dependent Kinase Inhibitor (Cdkn2a/Cdkn2b) Rs2383207 Are Associated With Ischemic Stroke In Indigenous West African Men, Rufus Akinyemi, Donna K. Arnett, Hemant K. Tiwari, Bruce Ovbiagele, Fred Sarfo, Vinodh Srinivasasainagendra, Marguerite Ryan Irvin, Abiodun Adeoye, Rodney T. Perry, Albert Akpalu, Carolyn Jenkins, Lukman Owolabi, Reginald Obiako, Kolawole Wahab, Emmanuel Sanya, Morenikeji Komolafe, Michael Fawale, Philip Adebayo, Godwin Osaigbovo, Taofiki Sunmonu, Paul Olowoyo, Innocent Chukwuonye, Yahaya Obiabo, Onoja Akpa, Sylvia Melikam, Raelle Saulson, Raj Kalaria, Adesola Ogunniyi, Mayowa Owolabi

Epidemiology and Environmental Health Faculty Publications

Background—Inherited genetic variations offer a possible explanation for the observed peculiarities of stroke in sub – Saharan African populations. Interleukin–6 polymorphisms have been previously associated with ischemic stroke in some non-African populations.

Aim—Herein we investigated, for the first time, the association of genetic polymorphisms of IL-6 and CDKN2A- CDKN2B and other genes with ischemic stroke among indigenous West African participants in the Stroke Investigative Research and Education Network (SIREN) Study.

Methods—Twenty-three previously identified single nucleotide polymorphisms (SNPs) in 14 genes of relevance to the neurobiology of ischemic stroke were investigated. Logistic regression models adjusting for known …

Linking Kindling To Increased Glutamate Release In The Dentate Gyrus Of The Hippocampus Through The Stxbp5/Tomosyn-1 Gene, Seth R. Batten, Elena A. Matveeva, Sidney W. Whiteheart, Thomas C. Vanaman, Greg A. Gerhardt, John T. Slevin

Psychology Faculty Publications

Introduction: In kindling, repeated electrical stimulation of certain brain areas causes progressive and permanent intensification of epileptiform activity resulting in generalized seizures. We focused on the role(s) of glutamate and a negative regulator of glutamate release, STXBP5/tomosyn-1, in kindling.

Methods: Stimulating electrodes were implanted in the amygdala and progression to two successive Racine stage 5 seizures was measured in wild-type and STXBP5/tomosyn-1^−/− (Tom^−/−) animals. Glutamate release measurements were performed in distinct brain regions using a glutamate-selective microelectrode array (MEA).

Results: Naïve Tom^−/− mice had significant increases in KCl-evoked glutamate release compared to naïve wild type as …

Impulsive Personality Dimensions Are Associated With Altered Behavioral Performance And Neural Responses In The Monetary Incentive Delay Task, Ruolei Gu, Yang Jiang, Seth Kiser, Chelsea L. Black, Lucas S. Broster, Yue-Jia Luo, Thomas H. Kelly

Behavioral Science Faculty Publications

Individual differences in dimensions of impulsivity personality including disinhibition and sensation seeking modulate approach responses to reinforcing stimuli, such as drugs and money. The current study examined the effects of monetary incentive on both behavioral performance and electrophysiological activity among individuals varying in disinhibition and sensation seeking. The monetary incentive delay (MID) task was completed under electroencephalogram (EEG) recording. Behavioral data showed that higher disinhibition and sensation-seeking were associated with lower performance accuracy. Event-related potential (ERP) data showed that high reinforcement cues elicited a larger late positive component (LPC) than other conditions among high disinhibition participants, indicating its strong emotional …

Optimization Of Mitochondrial Isolation Techniques For Intraspinal Transplantation Procedures, Jenna L. Gollihue, Samir P. Patel, Charles B. Mashburn, Khalid C. Eldahan, Patrick G. Sullivan, Alexander G. Rabchevsky

Physiology Faculty Publications

Background—Proper mitochondrial function is essential to maintain normal cellular bioenergetics and ionic homeostasis. In instances of severe tissue damage, such as traumatic brain and spinal cord injury, mitochondria become damaged and unregulated leading to cell death. The relatively unexplored field of mitochondrial transplantation following neurotrauma is based on the theory that replacing damaged mitochondria with exogenous respiratory-competent mitochondria can restore overall tissue bioenergetics.

New Method—We optimized techniques in vitro to prepare suspensions of isolated mitochondria for transplantation in vivo. Mitochondria isolated from cell culture were genetically labeled with turbo-green fluorescent protein (tGFP) for imaging and tracking purposes …

Identification Of Changes In Neuronal Function As A Consequence Of Aging And Tauopathic Neurodegeneration Using A Novel And Sensitive Magnetic Resonance Imaging Approach, Sarah N. Fontaine, Alexandria Ingram, Ryan A. Cloyd, Shelby E. Meier, Emily Miller, Danielle N. Lyons, Grant K. Nation, Elizabeth Mechas, Blaine Weiss, Chiara Lanzillotta, Fabio Di Domenico, Frederick A. Schmitt, David K. Powell, Moriel H. Vandsburger, Jose Francisco Abisambra

Sanders-Brown Center on Aging Faculty Publications

Tauopathies, the most common of which is Alzheimer’s disease (AD), constitute the most crippling neurodegenerative threat to our aging population. Tauopathic patients have significant cognitive decline accompanied by irreversible and severe brain atrophy, and it is thought that neuronal dysfunction begins years before diagnosis. Our current understanding of tauopathies has yielded promising therapeutic interventions but have all failed in clinical trials. This is partly due to the inability to identify and intervene in an effective therapeutic window early in the disease process. A major challenge that contributes to the definition of an early therapeutic window is limited technologies. To address …