Molecular and Cellular Neuroscience Commons^™

Lpa Receptors Modulate Gene Expression During Oligodendrocyte Differentiation, Samantha A. Spencer

Theses and Dissertations

LPA, produced by the lysoPLD activity of ATX, binds its cognate receptors and regulates the development of multiple brain cells, including oligodendrocytes (OLGs). OLGs progress through a lineage from precursor (OPC) to early OLG to immature OLG, until finally the cells mature and enwrap axons to enable saltatory conduction and provide trophic support. The studies in this dissertation characterized the receptors LPA4 and LPA6 as inhibitors of OPC differentiation. Western blot analysis of MS patient lesion tissue found a negative correlation between ATX levels and levels of LPA4 and LPA6. A previously created homology model for LPA4 was used to …

Exosomes As Systemic Mediators Of Nanotube Induced Neurotoxicity, Christopher G. Canal

Theses and Dissertations

Extra-pulmonary effects of nanoparticle inhalation have been well documented; however, mechanisms for conveying peripheral bioactivity remain elusive. Recent studies point to indirect molecular mediators shed into the circulation. Protein and lipid alternatives to cytokines or chemokines have been proposed, yet the diversity among responses suggests a broader assemblage of factors. Recently we have proposed proteolytic fragment peptides as an additional source of bioactivity, which interestingly were significantly associated with exosomal proteins after enrichment analysis. Here we tested whether modeled exposure to multi-walled carbon nanotubes (MWCNT) could alter the composition and bioactivity of circulating exosomes. Male C57BL/6 mice were exposed by …

Targeting The Nt17 Of The Huntingtin Protein Via Natural And Chemical Modifications: Impact On Aggregation And Membrane Interactions, Faezeh Sedighi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Huntington Disease (HD) is a fatal neurodegenerative disorder caused by an expanded polyglutamine domain (polyQ) in the first exon of the huntingtin protein (htt-exon1). The major hallmark of HD is the accumulation of aggregates into proteinaceous inclusion bodies. PolyQ expansion in huntingtin promotes self-assembly into a variety of toxic aggregates such as oligomers, fibrils, and amorphous aggregates. The resulting heterogeneous mixture of distinct species makes it difficult to assign a toxic function to specific aggregate structures. In addition, htt interacts with a variety of membranous surfaces. The first 17 amino acids (Nt17) of htt directly flanking the polyQ domain functions …

Factors Influencing Huntingtin Aggregation At Surfaces: Implications For Huntington’S Disease, Sharon E. Groover

Graduate Theses, Dissertations, and Problem Reports (ETD)

Huntington’s Disease (HD) is a genetic, neurodegenerative disease characterized by an abnormal polyglutamine (polyQ) expansion in the first exon of the huntingtin protein (htt). The polyQ domain facilitates aggregation and initiates the formation of a diverse collection of aggregate species, including fibrils, oligomers and annular aggregates. The first 17 amino acids of htt (Nt17) directly flank the polyQ domain and is a key factor in htt’s association to membranous structures. In addition to Nt17 being an amphipathic αhelix, it also promotes aggregation through self-association and contains numerous posttranslational modifications (PTMs) that can modulate toxicity and subcellular localization. For in depth …

The Interplay Of Progestins, Matrix Metalloproteinases, And The Aging Brain, Keyana Nicole Porter

Graduate Theses, Dissertations, and Problem Reports (ETD)

Progestins are synthetic hormones that are designed to mimic the biological actions of progesterone. They, however, possess other pharmacological actions and properties, in addition to their progestational activities. Medroxyprogesterone Acetate (MPA) is a progestin used globally in the hormonal contraceptive, Depo Provera®, by women in their reproductive prime and is a major compound found in hormone therapy (HT) formulations used by menopausal women. MPA is used by approximately 1 in 5 adolescents and adult women in the United States who are sexually active. Globally, nearly 48 million women utilize injectable contraceptives to prevent pregnancy, with most users utilizing MPA as …

The Wiring Logic Of Identified Serotonergic Neurons Across Olfactory Networks In Drosophila, Kaylynn E. Coates

Graduate Theses, Dissertations, and Problem Reports (ETD)

Serotonin is a ubiquitous neuromodulator that confers flexibility in networks to modulate a wide array of behavioral and physiological processes. However, due to the complexity and heterogeneity of serotonergic systems, it has been challenging to determine the patterns of connectivity as well as the physiological contexts that influence individual serotonin neurons. In this dissertation, I use two serotonergic neurons which innervate the Drosophila olfactory system, the CSDns, as a model to explore these broad questions comprehensively using anatomical approaches. I first show that the CSDns have distinct connectivity relationships with populations of antennal lobe principal olfactory neurons and that their …

Cerebrovascular Dysfunction And Degeneration In Alzheimer’S Disease Pathophysiology, Dominic Dimitri Quintana

Graduate Theses, Dissertations, and Problem Reports (ETD)

Alzheimer’s disease (AD) is a terminal illness and the most common form of dementia, which disproportionately affects the aged population. The pathophysiology of AD is characterized by neurodegeneration that slowly progresses, affecting regions of the brain that are involved in learning, memory, language, and executive function. In patients with the disease, early symptoms include non-disruptive forgetfulness that evolves into the inability to form new memories and ultimately the loss of autonomy at late stages. Histopathological hallmarks in the brain from patients with AD is the presence of amyloid-β (Aβ)-plaques and neurofibrillary tangles (NFT) deposited in the parenchyma. Since the discovery …

A Kinesin Adapter Directly Mediates Dendritic Mrna Localization During Neural Development In Mice, Hao Wu, Jing Zhou, Tianhui Zhu, Ivan Cohen, Jason Dictenberg

Publications and Research

Motor protein-based active transport is essential for mRNA localization and local translation in animal cells, yet how mRNA granules interact with motor proteins remains poorly understood. Using an unbiased yeast two–hybrid screen for interactions between murine RNA-binding proteins (RBPs) and motor proteins, here we identified protein interaction with APP tail-1 (PAT1) as a potential direct adapter between zipcode-binding protein 1 (ZBP1, a β-actin RBP) and the kinesin-I motor complex. The amino acid sequence of mouse PAT1 is similar to that of the kinesin light chain (KLC), and we found that PAT1 binds to KLC directly. Studying PAT1 in mouse …

Cerebro-Vascular Disruption Mediated Initiation And Propagation Of Traumatic Brain Injury In A Fluid Percussion Injury Model, Xiaotang Ma

Dissertations

Traumatic brain injury (TBI) is a major health problem for over 3.17 million people in the US. There is no FDA-approved drug for the treatment because the injury mechanisms have not been clearly identified. The knowledge gap is addressed here by the lateral fluid percussion injury (FPI) rat model, through the understanding of layer-structured mechanisms from physical vascular rupture to acute necrosis, as well as biochemical changes in perivascular space as secondary events.

Firstly, the cerebrovascular hemorrhage and related infarct volume are investigated as the primary events in moderate FPI, which is found to be increased with injury severity in …

Nanomedicine-Driven Neuropathic Pain Relief In Rat Model Is Associated With Macrophage Polarity And Mast Cell Activation, Muzamil Saleem

Electronic Theses and Dissertations

We explored the immune neuropathology underlying multi-day relief from neuropathic pain in a rat model initiated at the sciatic nerve by using a nanoemulsion-based nanomedicine as a biological probe. The nanomedicine is theranostic: both therapeutic (containing celecoxib drug) and diagnostic (containing near-infrared fluorescent (NIRF) dye) and is small enough to be phagocytosed by circulating monocytes. A model of neuropathic pain is initiated by tying four 1mm spaced knots around the sciatic nerve with chromic gut suture, which results in neuroinflammation, and a resultant pain-like behavior manifests. We show that pain-like behavior reaches a plateau of maximum hypersensitivity 8 days post-surgery, …

Roles Of Autism Gene Arid1b In Murine Brain Development And Behavior, Amanda L. Smith

Theses & Dissertations

Autism spectrum disorder (ASD) and intellectual disability (ID) are highly prevalent neurodevelopmental disorders characterized by social and communication deficits, stereotyped behaviors, cognitive dysfunction, and deficits in adaptive behaviors. The pathogenesis underlying these disorders remains unknown, and thus no pharmacologic or genetic therapies are currently available. Recent progress in the field has shown that haploinsufficiency of the AT-rich interactive domain-containing 1B (ARID1B) gene is a genetic cause of ASD and ID. Our lab recently developed an Arid1b knockout mouse model to better study its role in the pathogenesis of these disorders. One theory regarding the cause of neurodevelopmental disorders …

Cholesterol Biosynthesis In The Nervous System With An Emphasis On Desmosterolosis, Luke Allen

Theses & Dissertations

Cholesterol biosynthesis is integral to proper neurodevelopment due to the reliance on de novo synthesis of cholesterol in the brain. Disruptions in this process have devastating outcomes for human life characterized by several phenotypic manifestations concomitant with developmental delay. The cholesterol biosynthesis disorder desmosterolosis is an extremely rare disorder with a severe clinical phenotype, however, the models used to study this disease are not well characterized. In addition to genetic disruptions in cholesterol biosynthesis, pharmacological perturbation is an understudied side effect of many commonly prescribed drugs. Here we present a characterization of the sterol profile of the mouse model of …

Role Of Astrocyte-Derived Extracellular Vesicles In Neuroinflammation Mediated By Drug Abuse, Ke Liao

Theses & Dissertations

Neuronal damage and neuroinflammation is a hallmark feature of HIV-associated neurological disorders (HANDs). Opioids abuse accelerates the incidence and progression of HAND; however, the mechanisms underlying the potentiation of neuropathogenesis by these drugs remain elusive. Extracellular vesicles (EVs) are essential conduits in HIV and drug abuse-mediated synaptodendritic injury and neuroinflammation. Findings from our group have demonstrated that astrocyte-derived EV (ADEV)-miRNA-29b mediates HIV Tat and morphine-induced neuronal injury, thus underscoring the importance of such interactions in NeuroHIV.

Besides, HIV Tat and morphine-mediated synaptodendritic injury via ADEVs, we are also interested in whether ADEVs contributes to neuroinflammation. Microglia are critical players in …

Assessing The Morphology Of Vesicles In Inhibitory Symmetric Synapses In Safety And Fear Conditions In The Rat Lateral Amygdala, Valerie Kress

Honors Scholar Theses

There is a significant lack of research on vesicle morphology in inhibitory synapses in the rat lateral amygdala. Published research focuses heavily on excitatory synapses in different parts of the rat brain and even this research rarely focuses on the different vesicle types in axons. It is reported that in these axons, synaptic vesicles traditionally contain neurotransmitters while small dense core vesicles contain active zone proteins and large dense core vesicles contain neuropeptides. This study aims to find correlations between vesicle morphology, location, contents, and potential function of each of the different types of vesicle in inhibitory axons.

After reviewing …

Cognitive And Non-Cognitive Outcomes Associated With Student Engagement In A Novel Brain Chemoarchitecture Mapping Course-Based Undergraduate Research Experience., Christina D'Arcy, Anais Martinez, Arshad Khan, Jeffrey Olimpo

Selected Works Temporary Series

No abstract provided.

Cognitive And Non-Cognitive Outcomes Associated With Student Engagement In A Novel Brain Chemoarchitecture Mapping Course-Based Undergraduate Research Experience., D'Arcy, Anais Martinez, Arshad Khan, Jeffrey Olimpo

Departmental Papers (Biology)

No abstract provided.

Alzheimer's And Amyloid Beta: Amyloidogenicity And Tauopathy Via Dyshomeostatic Interactions Of Amyloid Beta, Jordan Tillinghast

Senior Honors Theses

This paper reviews functions of Amyloid-β (Aβ) in healthy individuals compared to the consequences of aberrant Aβ in Alzheimer’s disease (AD). As extraneuronal Aβ accumulation and plaque formation are characteristics of AD, it is reasonable to infer a pivotal role for Aβ in AD pathogenesis. Establishing progress of the disease as well as the mechanism of neurodegeneration from AD have proven difficult (Selkoe, 1994). This thesis provides evidence suggesting the pathogenesis of AD is due to dysfunctional neuronal processes involving Aβ’s synaptic malfunction, abnormal interaction with tau, and disruption of neuronal homeostasis. Significant evidence demonstrates that AD symptoms are partially …

Understanding Object Motion Encoding In The Mammalian Retina., Victor Julian Depiero

Electronic Theses and Dissertations

Phototransduction, transmission of visual information down the optic nerve incurs delays on the order of 50 – 100ms. This implies that the neuronal representation of a moving object should lag behind the object’s actual position. However, studies have demonstrated that the visual system compensates for neuronal delays using a predictive mechanism called phase advancing, which shifts the population response toward the leading edge of a moving object’s retinal image. To understand how this compensation is achieved in the retina, I investigated cellular and synaptic mechanisms that drive phase advancing. I used three approaches, each testing phase advancing at a …

A Novel Switch-Like Function Of Delta-Catenin In Dendrite Development, Ryan Baumert

Dissertations and Theses (Open Access)

The formation of neuronal networks in the brain is tightly regulated, and dependent on the morphology of dendrites, the branch-like signal-receiving structures extending from neurons. Disruptions in dendrite development, or dendritogenesis, can lead to the atypical neuronal connectivity associated with multiple neurodevelopmental diseases. My research addresses molecular processes that underlie dendritogenesis via analysis of a pair of novel interactions involving the protein delta-catenin.

In neurons, delta-catenin localizes to dendrites and synapses, where it functions in their development and maintenance. Structurally, delta-catenin possesses a central Armadillo domain and a C-terminal PDZ-binding motif. This motif associates with PDZ domain-containing proteins, and is …

Modeled Microgravity Induces Neutrophil Extracellular Trap (Net)Osis Formation And Reduced Phagocytosis Of Polymorphonuclear Neutrophils, Amber M. Paul

Publications

Spaceflight can dysregulate immunity, by way of increasing granulocytes numbers with impaired function. Polymorphonuclear neutrophils (PMN) are granulocytes that are first responders to infection or injury, and consist of the largest pool of immune cells in humans. PMNs function during innate immunity, through phagocytosis and promotion of inflammation, via the release of reactive oxygen species (ROS) mediators and granule-containing enzymes, such as myeloperoxidase (MPO) and NADPH oxidase-2 (NOX-2). In addition, neutrophil extracellular trap (NET) formation is another mechanism of PMN surveillance that works independently of engulfment phagocytosis, and is a last resort function that can induce NETosis or PMN-specific cell …