Molecular and Cellular Neuroscience Commons^™

Establishment Of A Hek293t Cell Model System To Investigate Direct Intracellular Interactions Between Amyloid-Β (Aβ) And The Nlrp3 Inflammasome, Cristina Sinobas Pereira

Dissertations

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder and the leading cause of dementia worldwide. While Amyloid-β (Aβ) aggregation is a defining pathological feature, increasing evidence highlights chronic neuroinflammation as a critical contributor to disease progression. Soluble Aβ assemblies can act as damage associated molecular patterns (DAMPs) including activation of the NLRP3 inflammasome, which links amyloid pathology to sustained inflammatory responses in the brain (Heneka et al., 2015; Nakanishi et al., 2018). However, the molecular mechanisms by which specific Aβ conformations influence inflammasome assembly remain incompletely understood.This study aimed to investigate whether distinct aggregation states of amyloid β42 (Aβ42) are …

Design And Advancement Of Analytical Frameworks For In Vivo Single-Photon Calcium Imaging To Characterize Temporal- And Treatment-Dependent Neural Adaptations To Opioid Exposure And Withdrawal In The Medial Prefrontal Cortex, Alexia R. Alsum Dr.

Theses and Dissertations--Pharmacy

Despite the availability of several approved medications for opioid use disorder (OUD), it remains a significant public health concern characterized by persistent neurobiological adaptations that drive relapse and impede successful recovery. The medial prefrontal cortex (mPFC), a region critical for executive control and decision-making, undergoes pronounced functional changes during chronic opioid exposure and withdrawal, yet the cellular mechanisms underlying these adaptations remain poorly understood. This dissertation aims to investigate longitudinal alterations in mPFC neural activity across opioid exposure and withdrawal using in vivo single-photon calcium imaging and newly developed computational frameworks.

Following standard preprocessing to extract and normalize calcium traces, …

Disrupted Circadian Rhythms Affect Hallmark Pathologies In Alzheimer’S Disease-Related Mouse Models, Valeria Buzinova

Theses and Dissertations--Molecular and Cellular Biochemistry

Alzheimer’s Disease (AD) is a complex neurodegenerative disease with two hallmark pathologies: extracellular amyloid-b (Ab) and intracellular neurofibrillary tangles (NFTs). Ab is proteolytically processed from amyloid precursor protein (APP) by b-secretase and g-secretase as a monomeric peptide prone to aggregation. Eventually, the aggregate-prone monomers will form dense plaques that are difficult to break down and remove. These plaques begin to deposit into the cortex decades prior to the formation of NFTs and the onset of cognitive decline. NFTs are comprised of hyper-phosphorylated tau. Tau is a protein that serves to promote and stabilize the formation of microtubules. The formation of …

Mechanistic Insights Into The Neuroprotective Effects Of The Antidepressant Agomelatine In Alzheimer's Disease, Grace Terry

Dissertations, Theses, and Capstone Projects

Alzheimer’s Disease (AD) is a complex neurodegenerative disease that has limited treatment options and no cure. AD is characterized by robust pathology including extracellular amyloid beta plaques, intracellular neurofibrillary tangles, neuronal and synaptic loss, neuroinflammation, and brain atrophy. AD presents with cognitive decline and memory loss but only years after neuropathology has started to accumulate. This robust pathology has made AD difficult to treat and highlights the need for therapeutics that modulate multiple pathways. Agomelatine (AGO) was selected by a high-throughput machine learning drug repurposing algorithm by our collaborator Dr. Lie Xie (Hunter College Dept. of Comp. Sci.) as having …

Advanced Interactions Of Directed Energy With Retinal Pigment Epithelial Cells And Their Photochemical And Photothermal Responses, Jin B. Ha

Theses & Dissertations

Excess optical radiation can injure the retina through either rapid heat deposition (photothermal damage) or cumulative photo‑oxidative stress (photochemical damage), yet current laser‑safety limits treat these mechanisms as independent. To test that assumption, this dissertation integrated systematic wavelength, duration and temperature‑controlled laser exposures with live/dead fluorescence imaging in a melanin‑loaded hTERT‑RPE1 monolayer model. First, concurrent 447 nm (blue) and 2 µm (infra‑red) beams delivered for 200 s demonstrated a strong thermal–photochemical synergy: each beam alone was sub‑threshold (≤25 % lethality) but together produced 100 % RPE death without exceeding 50 °C, proving that modest heating markedly lowers the photon dose …

Aptamer Selection And Development Of Electrochemical Aptamer-Based Sensors For Neuropeptide Y, Evelyn Adela Carreto Guevara

Department of Chemistry: Dissertations, Theses, and Student Research

In this thesis, we report the results of four aptamers obtained from an aptamer selection process called the systematic evolution of ligands by exponential enrichment (SELEX) with affinity to Neuropeptide Y (NPY). NPY is a highly abundant peptide transmitter with widespread distribution throughout the body which affects various physiological functions. These functions include energy homeostasis, appetite regulation, stress response, and anxiety regulation. Dynamic monitoring of NPY levels is crucial for better understanding behaviors in individuals with neurological disorders associated with NPY. Aptamers are synthetic oligonucleotides obtained through SELEX which have a binding affinity to a target of interest when in …

Apolipoprotein E4, Tauopathy, And Brain Injury: Molecular Insights Into Alzheimer's Disease Pathology, Nashanthea J. Roland

Theses & Dissertations

Alzheimer’s disease (AD) is the world’s leading cause of dementia, characterized by progressive atrophy of the hippocampal and cortical brain regions, synapse damage and loss, and a buildup of senile plaques and neurofibrillary tangles composed of β-amyloid peptides and hyperphosphorylated tau, respectively. While age is the most significant risk factor for developing AD, apolipoprotein E4 (APOE4) is the strongest genetic risk factor for AD. Although it is known that APOE4 influences tau pathology, the molecular mechanisms by which APOE4 drives AD pathogenesis and progression remain unclear. In addition to intrinsic contributions to AD, there are many extrinsic factors that can …

Assessing The Behavioral Impact Of Pyridostigmine Bromide In Rats, Noah A. Martin

Honors Theses

Pyridostigmine bromide (PB) is an organophosphate (OP) nerve agent prophylactic used to protect warfighters against chemical warfare agents. OPs inhibit the neural enzyme acetylcholinesterase (AChE) in the brain. This leads to the buildup of acetylcholine, causing respiratory failure, seizures, and death. PB functions by inhibiting ~30% of peripheral AChE temporarily, protecting the enzymes so that the body is able to restore sufficient cholinergic function post-exposure. PB does not cross the blood-brain barrier, though it may still indirectly affect toxicity in the brain due to repeated AChE inhibition throughout treatment, or by inhibition of non-target ChE’s in the blood. The aim …

In-Silico Modeling And Characterization Of Kcc2 Protein Interaction With A Small Molecule Direct Agonist Identifies Potential Binding Sites For Modulating Behaviors Associated With Substances Of Abuse, William Hai Dang Ho, Alfred Amendolara, Kenyon Mitchell, Jaden Miner, Ruth Northcott, Braxton Bingham, Andrew J. Payne

Annual Research Symposium

Purpose

KCC2 is a potassium-chloride cotransporter that plays a critical role in neuronal function by regulating GABAergic signaling via chloride gradients. Maintaining this concentration gradient is crucial for balancing excitation and inhibition in the brain. While KCC2 dysregulation has been implicated in epilepsy and seizures, recent studies suggest that KCC2 inhibition results in phenotypes mirroring those seen in chronic opioid dependence. As such, increasing evidence support KCC2 being a potential therapeutic target for modulating behaviors associated with substances of abuse. Currently, only a few direct small molecule agonists against KCC2 have been reported, and no definitive active site on the …

Technological Development Of In-Cell Nmr: Microfluidic, Metabolomic, And Fluxomic Approaches, Nicholas Sciolino

Electronic Theses & Dissertations (2024 - present)

In the fields of structural biology, metabolomics, and fluxomics, there is a driving, technique-based concern when it comes to high-resolution spectrometry and its marriage to biological and physiological relevance. Sample preparation often involves cellular perturbation, lysate separation schemes, combinations with non-biological reagents, and timeline slack. Conceptually, the farther we get from the cell, the greater the potential disparity between what exists in vivo and our in vitro manipulations. This is particularly true when seeking to collect data on transfected targets of interest, and on sensitive metabolic equilibria that occur on the order of minutes. The question remains: if we are …

Ciliary Arl14b In Vision, Alexis Breann Crockett

Graduate Theses, Dissertations, and Problem Reports (ETD)

Primary cilia are highly specialized organelles that regulate signaling, trafficking, and sensory perception across multiple tissues, including the retina. The small GTPase ADP Ribosylation Factor-Like Protein 13B (ARL13B) is an atypical ARF-family protein enriched in cilia. ARL13B acts as a guanine exchange factor (GEF) for another small GTPase ARF-like Protein 3 (ARL3). Mutations in ARL13B cause Joubert syndrome, a ciliopathy characterized by brain malformation, developmental delays, and retinal degeneration. Despite ARL13B’s known ciliary localization and clinical relevance, ARL13B’s precise functions in cilia remain poorly defined. This dissertation investigates the cilia-specific roles and GEF-specific roles of ARL13B in photoreceptors using two …

Characterization Of Stealth Liposome-Based Nanoparticles Encapsulating Acat1/Soat1 Inhibitor F26: Potential Therapeutics For Niemann-Pick Type C And Other Neurodegenerative Diseases., Junghoon Lee

Dartmouth College Ph.D Dissertations

Cholesterol dysregulation is implicated in neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson’s disease (PD), Huntington’s disease (HD) and Niemann-Pick type C disease (NPCD). This study focused on evaluating the potent ACAT1 inhibitor, F26, as a therapeutic strategy for NPCD. F26 demonstrated superior ACAT1 inhibition and efficacy compared to the previously studied inhibitor, F12511, both in vitro and in vivo. Notably, F26 exhibited enhanced pharmacokinetic properties, including prolonged duration of action and better brain retention, making it a more promising candidate for treating neurodegenerative diseases.

F26 was encapsulated in a liposome-based nanoparticle system, DSPE-PEG2000 with phosphatidylcholine (PC), for enhancing its …

Towards A New Role Of Mitochondrial Hydrogen Peroxide In Synaptic Function, Cliyahnelle Z. Alexander

Student Theses and Dissertations

Aerobic metabolism is known to generate damaging ROS, particularly hydrogen peroxide. Reactive oxygen species (ROS) are highly reactive molecules containing oxygen that have the potential to cause damage to cells and tissues in the body. ROS are highly reactive atoms or molecules that rapidly interact with other molecules within a cell. Intracellular accumulation can result in oxidative damage, dysfunction, and cell death. Due to the limitations of H₂O₂ (hydrogen peroxide) detectors, other impacts of ROS exposure may have been missed. HyPer7, a genetically encoded sensor, measures hydrogen peroxide emissions precisely and sensitively, even at sublethal levels, during …

The Effect Of Novel Microtubule Modulators On Experimental Lewy Body Disease, Anuj S. Jamenis

Electronic Theses and Dissertations

In Lewy body disorders, α-synuclein aggregates are believed to destabilize the microtubular framework. However, microtubules are a challenging therapeutic target, as excessive rigidity or flexibility afforded by microtubule modulators may be neurotoxic. Thus, the objective of the present study was to evaluate dual-acting microtubule- stabilizing/destabilizing agents in cellular and animal models of early-stage Lewy body disease.

In Aim 1 we tested the dual-acting tricylic pyrimido[4,5-b]indole analogs AG161-47 and AG161-41 in an in vitro preformed fibril induced model of Lewy body disease. We found that both compounds reduced preformed fibril-seeded α-synucleinopathy without toxicity in primary hippocampal cultures. AG161-47 subtly impacted microtubule …

Unveiling The Nexus Of Cellular Quality Control: Exploring The Interplay Between Ribosome-Associated Protein Quality Control And Mitochondrial Quality Control Pathways, Foozhan Tahmasebinia

Biological Sciences Theses and Dissertations

In eukaryotic cells, the intricate interplay between cellular quality control mechanisms is crucial for maintaining homeostasis and safeguarding the integrity of vital processes, spanning from macromolecule synthesis to the renewal of entire cellular organelles.

Disruption of these networks can lead to severe diseases such as metabolic disorders, underscoring the interconnected nature and feedback control mechanisms inherent in biological systems, including cellular quality control systems. This interconnectedness extends to the intricate communication between organelles, enabling coordinated functioning and adaptation to changing cellular conditions, particularly in response to stressors.

While the exact mechanisms governing these communications within cellular quality control systems remain …

Investigating The Roles Of Dapk, P53/Cep-1, And Mitochondrial Damage In Necrotic Neurodegeneration In C. Elegans, Anil Singh

Dissertations and Theses

Stroke is one of the leading causes of death in the U.S., with minority groups, suffering higher fatality rates. Stroke is caused by ischemia, where occlusion of blood supply to the brain results in neurodegeneration. Most of the damage is attributed to excitotoxicity, where an accumulation of the neurotransmitter glutamate in the synapse overstimulates postsynaptic neurons and ultimately leads to cell death (largely by necrosis). Stroke treatments are often ineffective, due to the delay between the onset of stroke and the delivery of effective treatment. To address this, we focus our study on putative later-acting mediators of excitotoxicity such as …

Structural And Functional Consequences Of Pde6 Prenylation In Rod And Cone Photoreceptors, Faezeh Moakedi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Phosphodiesterase-6 (PDE6) serves as a pivotal component in the phototransduction pathways of both cone and rod photoreceptors. In cones, PDE6 consists of tetrameric subunits: inhibitory (γ') and catalytic (α'). The catalytic subunit, PDE6α', contains a C-terminal prenylation motif. Deletion of this motif is associated with achromatopsia (ACHM), a form of color blindness. The mechanisms underlying the disease and the roles of PDE6 lipidation in vision remain elusive. Meanwhile, rod PDE6 is composed of α and β catalytic subunits and γ inhibitory subunits, with alterations in the C-terminal "prenylation motif" of PDE6β linked to retinitis pigmentosa (RP) pathology. In this comprehensive …

Characterization Of Pathological Tau Mutants, Charles J. Mcdonald

Dissertations, Theses, and Capstone Projects

Tau is a protein expressed exclusively in glia and neurons in the central nervous system and implicated in several neurogenerative diseases called “tauopathies”. Among all the tauopathies, one third is characterized by the presence of genetic mutations leading to the synthesis of tau proteins with single amino acid substitutions at specific locations and affecting protein function. While most of the initial studies have emphasize the functional role of tau as modulator of the axonal cytoskeleton, it has recently been well accepted that tau is also an intrinsically disordered protein that tends to form membraneless organelles called coacervates, due to a …

Changes In The Epigenetic Landscape Of Oligodendrocyte Progenitor Cells With Time, David K. Dansu

Dissertations, Theses, and Capstone Projects

Most neonatal oligodendrocyte progenitors (nOPCs) give rise to myelinating oligodendrocytes during development, while a proportion are retained as proliferative undifferentiated cells in the adult brain (aOPCs). Previous studies have reported distinct properties for those two populations but the molecular mechanisms underlying these intrinsic differences are not well understood. Using RNA-sequencing and unbiased histone proteomics analysis, we identify transcripts and histone marks that are higher in aOPCs than nOPCs. The genome-wide ChIP-sequencing analysis of chromatin from aOPCs compared to nOPCs detects greater occupancy of the H4K8ac mark at loci corresponding to the higher transcript levels of oligodendrocyte-specific transcription factors and lipid …

Probing Amyloid-Beta Protein Structure And Dynamics With A Selective Antibody, Shikha Grover

Dissertations

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder. The AD brain is characterized by significant neuronal loss and accumulation of insoluble fibrillar amyloid-β protein (Aβ) plaques and tau protein neurofibrillary tangles in the brain. However, over the last decade, many studies have shown that the neurodegenerative effect of Aβ may in fact be caused by various soluble oligomeric forms as opposed to the insoluble fibrils. Furthermore, the data suggest that a pre-fibrillar aggregated form, termed protofibrils, mediates direct neurotoxicity, and triggers a robust neuroinflammatory response.

Antibodies targeting the various conformation of Aβ are important therapeutic agents to prevent the progression …

Investigating Visinin-Like Protein 1 And Ubiquitinated Visinin-Like Protein 1 As Mild Traumatic Brain Injury Biomarkers, Yueming Wu

Theses and Dissertations--Chemistry

Traumatic brain injury (TBI) continues to be a significant cause of morbidity and mortality worldwide. Despite significant progress in understanding the complex pathophysiology of TBI, the underlying mechanisms remain poorly understood. The primary brain damage is acute and irreversible. However, secondary brain injuries often develop gradually over months to years, creating an opportunity for critical therapeutic interventions. In the past decade, research on TBI biomarkers has seen significant progress. This progress has been driven by the diverse nature of TBI pathologies and the challenges they present for evaluation, management, and prognosis. TBI biomarker proteins resulting from axonal, neuronal, or glial …

Brain Glycogen – Beyond Energy Storage In Glycogen Storage Diseases, Kia H. Markussen

Theses and Dissertations--Molecular and Cellular Biochemistry

Glycogen is a carbohydrate molecule that is traditionally viewed as a convenient and easily accessible energy storage form of glucose. However,emerging evidence supports the role of glycogen as more than a glucose storage form. During the last 20 years, glycogen has been shown to play pivotal roles in learning and memory, signaling events, viscosity, protein glycosylation, and be acritical hallmark in devastating diseases. Not only, does glycogen play a role as an energy substrate and critical metabolite during energy deprivation, glycogen is central for neurotransmitter homeostasis, tumor initiation, and ontributes to proper protein glycosylation in the brain. In this work, …

Heat Shock Protein 90 (Hsp90) System In Health And Disease., Daniella Munezero

Graduate Theses, Dissertations, and Problem Reports (ETD)

Cells rely on heat shock proteins (HSP) to facilitate and regulate the folding of the substrate proteins into their native state, and degradation if misfolding cannot be prevented. HSP90, a member of the HSP family, is a potential target for treatment of cancer and neurodegenerative diseases. Unfortunately, several clinical trials for cancer treatment have been discontinued due to cell toxicity accompanying HSP90 inhibition. HSP90 has four distinct but structurally similar paralogs. HSP90 inhibitors target all the paralogs despite increasing proof of functional differences among the paralogs. Understanding the in vivo function of HSP90 and the role played by each paralog …

The Role Of Parkin In Mitochondrial Dna, Eliezer Lichter

Theses & Dissertations

Mitochondria are at the center of biological phenomena such as aging and diseases, especially neurodegenerative diseases. While the discovery of mitochondria only came approximately 200 years after the cell was discovered, a lot of progress has been made since. The mitochondrial genome encodes proteins vital for mitochondrial function. These proteins are only a subset of the proteins present in mitochondria; the rest are nuclear encoded. The nucleus also encodes cytosolic proteins vital for mitochondrial maintenance. One of these is Parkin, an E3 ubiquitin ligase that ubiquitinates mitochondrial proteins as mitochondria become depolarized. Its activity has been shown to be involved …

Metoprolol Disrupts Sterol Biosynthesis Through Inhibition Of 7-Dehydrocholesterol Reductase (Dhcr7), Luke B. Allen

Theses & Dissertations

Cholesterol is essential for life. It is particularly important in the brain as it relies on de novo synthesis of cholesterol following the formation of the blood brain barrier (BBB). As such, disrupting sterol biosynthesis during neurodevelopment can have devastating outcomes. The most common post-lanosterol sterol biosynthesis disorder, Smith-Lemli-Opitz Syndrome, arises from a faulty DHCR7 enzyme. DHCR7 has also been shown to be inhibited by several psychotropic medications. Here we assess six beta-blockers and their effects on sterol biosynthesis in vitro. Two beta-blockers, metoprolol and nebivolol strongly inhibit DHCR7 in four separate in vitro models of both mouse and …

Role Of Nuclear Lamins In Oligodendrocyte Lineage Cells, Camila Yattah

Dissertations, Theses, and Capstone Projects

Differentiation of oligodendrocytes from progenitor cells is a highly regulated process characterized by a series of molecular changes, resulting in nuclear and morphological features unique to the mature oligodendrocyte state. Heterochromatin formation starting at the nuclear periphery, as well as increased nuclear rigidity are characteristically observed. The nuclear periphery is characterized by the presence of the nuclear lamina and it has been implicated in higher-order genome organization in cells. Lamins are the protein components of the nuclear lamina, and their expression is dependent upon the cell differentiation stage of the cells. While Lamin B1 (LMNB1) expression is high in progenitors …

Novel Therapeutic Strategies For Alzheimer’S Disease: Prostaglandin D2 Signaling And Its Human Polymorphisms As Well As A Polypharmacological Approach, Charles H. Wallace

Dissertations, Theses, and Capstone Projects

Alzheimer’s disease (AD) is an age related neurodegenerative disease with pathology that includes amyloid plaques, neurofibrillary tangles and non-resolving neuroinflammation. Non-resolving neuroinflammation lasts the entire course of the disease and has deleterious effects and is often thought to accelerate AD pathology. Non-Steroidal Anti-inflammatory Drugs (NSAIDs) have commonly been used as therapeutics to treat pain, inflammation and vascular. NSAIDs work by altering the cyclooxygenase (COX) mediated biosynthesis of prostaglandins which are lipid mediators that have many physiological functions, for example nociception, inflammation and vasodilation. Epidemiological studies support the notion that NSAIDs could be used to treat AD. Yet, clinical trials using …

Innate Immunity In The Pathobiology And Treatment Of Infectious And Neurodegenerative Diseases, Mai Mostafa

Theses & Dissertations

Mononuclear phagocytes (MPs; monocytes, macrophages, and dendritic cells) are the governors of innate immunity which is the body’s first line of defense against microbial pathogens. They act beneficial or detrimental. They are crucial for an effective non-specific immune response to invading pathogens by engulfing, destroying, then eliciting an adaptive specific immune response. Given their pivotal functions in the host immune defense, studying MP immune responses in disease is paramount important for understanding disease pathobiology and uncovering therapeutic strategies.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the driver of acute respiratory distress syndrome (ARDS) in coronavirus disease 2019 (COVID-19) amongst …

Vitamin D And Its In Vitro Therapeutic Action Mediated Through Vdr Rather Than Pdia3, Jaeden Pyburn

Undergraduate Honors Theses

Brain calcification is a common occurrence in the aging process, with >20% of individuals over the age of 65 showing hardened plaques in the basal ganglia. Loss of the vitamin D receptor (VDR) in transgenic mice leads to formation of calcified plaques in the basal ganglia and thalamus within the mice. Vitamin D signals through two known vitamin D responsive proteins, protein disulfide isomerase A3 (PDIA3) and VDR. In vitro, vitamin D has been demonstrated to suppress calcification in osteoblast-like cells. Here, we aim to elucidate which of either PDIA3 or VDR transduce vitamin D mediated suppression of calcification in …

The Effects Of Neuronal Growth Factors On Lps-Activated Schwann Cells, Caitlyn E. Henry, Peyton Kimmel, Angela Asirvatham Ph.D.

Student Research Poster Presentations 2022

Schwann cells (SCs) are the principal support cells of neurons in the peripheral nervous system, that both myelinate axons for the rapid conduction of electrical impulses as well as assist in axonal repair during nerve injury. During nerve injury, SCs secrete tumor necrosis factor alpha (TNF-α)^1,5,6 and other proinflammatory mediators^1,6, attracting macrophages to the site of injury to induce inflammation and clear myelin debris.^1,6 Once the debris is cleared, the neuron stimulates SC proliferation by secreting neuronal mitogens, such as heregulin^3,4, and an unknown factor that activates the cAMP pathway³, an important …