Molecular and Cellular Neuroscience Commons^™

Investigating Tumor Growth And Regulation In Supratentorial Ependymomas; The Impact Of Dlk1 And Egr1 Knockout, Om Sinojia

Honors Scholar Theses

Ependymomas (EPNs) are primary brain tumors that often arise from radial glial cells lining the ventricular system. Supratentorial ependymomas (ST-EPNs) are particularly aggressive, and understanding the molecular factors driving their growth is critical for developing targeted therapies. This study investigates the roles of DLK1 and EGR1, key regulators in cellular differentiation and tumorigenesis, in the development of ST-EPNs. We utilized genetically engineered mouse models to induce postnatal knockouts of DLK1 and EGR1 and evaluated tumor growth using histological and imaging techniques. Tumor area was quantified across multiple brain sections from both male and female mice. DLK1 knockout brains exhibited consistent …

The Relationship Between Amygdala And Orbitofrontal Cortex Volume In The Context Of Oppositional Defiant Disorder, Rahul Alla

Honors Scholar Theses

Disobedient and rebellious attitude in children is on the rise and this type of behavior is categorized as Oppositional Defiant Disorder (ODD). ODD in children can be identified as a persistent pattern of angry or irritable mood, argumentative or defiant behavior or vindictiveness toward others according to the Diagnostic and Statistical Manual (DSM-5, Fifth Edition) of Mental Disorders.1 Children with ODD typically have difficulty regulating and processing their emotions. Issues with regulating emotions is defined as the process by which individuals “influence which emotions they have, when they have them, and how they experience and express them”.2 Dysregulation of emotions …

Development Of Vasculature Patterns In A Mouse Model Of Supratentorial Ependymoma, Jackson Ayers

Honors Scholar Theses

Supratentorial Ependymoma (ST-EPN) is a subtype of ependymoma, a primary solid tumor found throughout the nervous system. ST-EPN are most commonly caused by an oncogenic fusion between the zinc finger gene ZFTA and the RELA, and this distinct ependymoma subtype is readily modeled in mice by conditional expression of ZFTA-RELA in radial glial cells. ST-EPN are known to have a distinctive arrangement of tumor cells and vasculature forming pseudo-rosettes in which polarized tumor cells surround blood vessels within the tumors. It is not known how these pseudo-rosettes or the tumor vasculature form and develop in ST-EPN, so in this study …

Investigating Sexual Dimorphism In Lateral Hypothalamic Melanin-Concentrating Hormone Neuron Subpopulations, Mahitha Juttu

Honors Scholar Theses

The lateral hypothalamic area (LHA) is an area crucial for coordinating key behaviors such as sleep, wakefulness, stress, and feeding. Within this area in the brain, Melanin concentrating hormone (MCH) neurons are exclusive to the LHA and also contribute to these key homeostatic behaviors. These neurons can be divided into two different subpopulations: MCH neurons that express cocaine amphetamine-regulated transcript (CART) tachykinin-3 receptor (NK3R) and MCH neurons that do not express CART and NK3R. These neuronal subpopulations have been implicated in coordinating key behaviors but have not been well studied.

In this paper, our project seeks to analyze how the …

Characterizing Rat Lateral Amygdala Interneurons By Colocalization Of Calcium-Binding Proteins Via Serial Multiplex Immunohistochemistry, Ethan Gasteyer

Honors Scholar Theses

The lateral amygdala is a brain structure that plays an important role in regulating fear and anxiety. Some anxiety disorders are hypothesized to develop from failures in this local inhibitory circuit. Distinct populations of these inhibitory neurons express patterns of calcium- binding proteins and neuropeptides that suggest differences in functionality within the lateral amygdala. Furthermore, these patterns of expression are compared between male and female rats to identify sex differences in the lateral amygdala. Previous studies have reported sex differences in amygdala activation and connectivity, but very little is known about the sexual dimorphism of calcium-binding protein and neuropeptide expression. …

Anatomical Characterization Of Descending Projections Of Lateral Hypothalamic Glutamatergic And Gabaergic Neurons, Jeremy Lesser

Holster Scholar Projects

Important innate behaviors in mammals, such as sleep-wake regulation, arousal, eating, drinking, and stress, are associated with the lateral hypothalamic area (LHA). The LHA is a complex brain region consisting of broad populations of either excitatory glutamatergic neurons or inhibitory GABAergic neurons. Recent studies have revealed dense and heterogeneous fibers from both LHA populations projecting to neuromodulatory regions in the midbrain and brainstem, including the tuberomammillary nucleus (TMN), ventral tegmental area (VTA), dorsal raphe (DR), and locus coeruleus (LC). Viral tracing and immunohistochemistry were utilized to characterize the anatomy of LHAVGLUT2 and LHAVGAT projections to the aforementioned regions in an …

Identification Of Secretion Factors That Restructure Neural Tissue In A Model Of Low Grade Glioma, Jackson Ayers

Holster Scholar Projects

Pediatric Low-grade Gliomas account for up to ⅔ of all pediatric tumors. Despite their low grade classification, they have the ability to mutate farther to a grade 3 or 4 neurological tumor, exponentially decreasing treatment and survival rates. Identifying the specific secretion factors associated with these tumors is extremely beneficial towards possible treatment options. CRISPR/Cas9 constructs were implemented to knock out GDF-15 and CCl-3 secretion factors in the presence of a BRAFV600E mutation before concentrated DNA plasmids were injected and integrated into the brains of mice embryos through In Utero Electroporation (IUE). The brains were subsequently stained through an immunohistochemistry …

Identifying The Cell Composition And Clonal Diversity Of Supratentorial Ependymoma Using Single Cell Rna-Sequencing, James He

University Scholar Projects

Ependymoma is a primary solid tumor of the central nervous system. Supratentorial ependymoma (ST-EPN), a subtype of ependymomas, is driven by an oncogenic fusion between the ZFTA and RELA genes in 70% of cases. We introduced this fusion into neural progenitor cells of mice embryos via in utero electroporation of a non-viral binary piggyBac transposon system containing ZFTA-RELA. From preliminary data in the LoTurco lab, inducing the expression of ZFTA-RELA into different neural progenitor cells produces tumors of varying lethality and cellular composition. To define the cellular composition and subclonal diversity of ST-EPN tumors, we used single cell RNA-sequencing to …

Identifying The Cell Composition And Clonal Diversity Of Supratentorial Ependymoma Using Single Cell Rna-Sequencing, James He

Honors Scholar Theses

Ependymoma is a primary solid tumor of the central nervous system. Supratentorial ependymoma (ST-EPN), a subtype of ependymomas, is driven by an oncogenic fusion between the ZFTA and RELA genes in 70% of cases. We introduced this fusion into neural progenitor cells of mice embryos via in utero electroporation of a non-viral binary piggyBac transposon system containing ZFTA-RELA. From preliminary data in the LoTurco lab, inducing the expression of ZFTA-RELA into different neural progenitor cells produces tumors of varying lethality and cellular composition. To define the cellular composition and subclonal diversity of ST-EPN tumors, we used single cell RNA-sequencing …

The Effects Of Mapk Signaling On The Development Of Cerebellar Granule Cells, Kerry Morgan

University Scholar Projects

The granule cells are the most abundant neuronal type in the human brain. Rapid proliferation of granule cell progenitors results in dramatic expansion and folding of the cerebellar cortex during postnatal development. Mis-regulation of this proliferation process causes medulloblastoma, the most prevalent childhood brain tumor. In the developing cerebellum, granule cells are derived from Atoh1-expressing cells, which arise from the upper rhombic lip (the interface between the roof plate and neuroepithelium). In addition to granule cells, the Atoh1 lineage also gives rise to different types of neurons including cerebellar nuclei neurons. In the current study, I have investigated the …

The Effects Of Mapk Signaling On The Development Of Cerebellar Granule Cells, Kerry Morgan

Honors Scholar Theses

The granule cells are the most abundant neuronal type in the human brain. Rapid proliferation of granule cell progenitors results in dramatic expansion and folding of the cerebellar cortex during postnatal development. Mis-regulation of this proliferation process causes medulloblastoma, the most prevalent childhood brain tumor. In the developing cerebellum, granule cells are derived from Atoh1-expressing cells, which arise from the upper rhombic lip (the interface between the roof plate and neuroepithelium). In addition to granule cells, the Atoh1 lineage also gives rise to different types of neurons including cerebellar nuclei neurons. In the current study, I have investigated the …

Kcnq2 Localization In The Brainstem, Christina Valera

Honors Scholar Theses

KCNQ2 channels are potassium channels that serve to control neuronal excitability. Loss of function mutations in these channels are known to cause various forms of epilepsy. Recently, KCNQ2 R201C and R201H gain of function mutations have been shown to exhibit an exaggerated startle response and other unique phenotypes uncharacteristic of epilepsy. These phenotypes resemble hyperekplexia, a condition in which glycine neurotransmission in the spinal cord and brainstem is affected. While KCNQ2 has widespread localization throughout the brain, its presence in the brainstem remains unknown. We used immunostaining to determine the localization of KCNQ2 in the vagus nerve and hypoglossal nerve …

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 …

Notch Inhibitors And The Bet Inhibitor Jq-1 Decrease The Growth Of Primary Tumor Cells Derived From A Novel Mouse Model Of C11orf95-Rela Induced Brain Tumor, Ericka Randazzo, Jesse Dunnack, Justin Fang, Joseph Loturco Phd

University Scholar Projects

Brain tumors are the most common childhood solid malignancy, and because of remarkable advances in treating many cancers outside of the brain, they have become the leading cause of cancer mortality in children. Ependymomas are a class of brain tumors which can be further subdivided into three groups based upon their location and genetic features. Of the three classes, supratentorial ependymomas are the only subgroup known to be marked by an oncogenic driver gene, which consists of a fusion mutation between the C11orf95 and RELA genes. C11orf95-RELA positive tumors are the most aggressive and lethal of …

Quantifying Expression Of Interneuron Subtype Markers For Dlx-2 Transfected Ng2 Cells, Timothy Nolan

Honors Scholar Theses

Neurons are a post-mitotic cell population, and therefore, they are not able to regenerate in vivo after a traumatic injury. Because inhibitory GABAergic interneurons and oligodendrocyte precursor cells (OPCs) are derived from the same precursor, recent studies have focused on transforming these OPCs into GABAergic neurons. However, there are different types of GABAergic interneurons that have different electrophysiological responses, which can lead to functional differences. The Nishiyama laboratory had already used a key gene in GABAergic interneuron and OPC differentiation, Distal-less homeobox 2 (Dlx-2), to transfect OPCs; early electrophysiology tests showed most of these transfected cells behaved like immature neurons, …

Is Concussion-Related Sleep Disturbance Present After Return To Play In College Athletes?, Alexander Gallaer

Honors Scholar Theses

As one of the most commonly experienced symptoms, the ramifications of sleep disruption as a result of concussion are potentially great, yet widely unexplored. Particularly troublesome is murky data regarding the length of sleep disruption following a concussion. By analyzing self-reported sleep data via the Pittsburgh Sleep Quality Index, this study seeks to investigate potential differences in sleep quality between injured college athletes 40 days after they have been cleared to play and matched controls. Data was analyzed using ANOVA analysis as well as Pearson correlation. No significant differences were found in sleep quality between groups, nor was there a …

Reconstitution Of Gabaergic Postsynapses In Host Cells, Karthik Kanamalla

Honors Scholar Theses

Type A GABA receptors (GABAARs) can be found embedded in postsynaptic membranes or in a variety of extrasynaptic locations. Receptors with synaptic function are recruited to the postsynapse by submembranous scaffolds composed of gephyrin and collybistin (CB). This study was aimed at assessing whether the ability to interact with the scaffold differentiates synaptic from non-synaptic receptors. Using HEK293 cells as an expression system, and indirect immunofluorescence (IF), co-localization of extrasynaptic receptors α1β3δ and α4β3δ with the CB-gephyrin scaffold was assessed and compared with that of the synaptic receptor α1β3γ2. Results indicated that both extrasynaptic receptors were able to colocalize with …

Exploring The Effect Of Novel Small Molecules On Oligodendrocyte Precursor Proliferation, Sagune Sakya

University Scholar Projects

Gliomas, a type of brain tumor, can be difficult to treat and have a poor survival rate. One pathway that leads to glioma formation is excessive signaling by platelet derived growth factors (PDGF) through PDGF receptor α (PDGFRα). Through this research, I found that novel compounds that downregulate PDGFRα decrease proliferation of Oli-neu cells, an oligodendrocyte precursor cell model, and identified signaling pathways through which these compounds may exert their effect. Further investigation may identify targets for development of glioma treatments.

Pathological Effects Of Repeated Concussive Tbi In Mouse Models: Periventricular Damage And Ventriculomegaly, Richard H. Wolferz Jr.

Honors Scholar Theses

Repeated concussive traumatic brain injury (rcTBI) is the most prominent form of head injury affecting the brain, with an estimated 1.7 million Americans affected each year (Kuhn 2012). Neurologists have been concerned about the danger of repeated head impacts since the 1920’s, but researchers have only begun to understand the long-term effects of rcTBI (McKee 2009). Although symptoms can be as mild as dizziness, current research suggests that multiple concussions can lead to a progressive degenerative brain disease known as chronic traumatic encephalopathy (CTE) (Luo 2008, McKee 2009, Kane 2013). Research on the brain is just beginning to scratch the …

Astroglial Boundary Formation And Epha4 Signaling In Neuroblast Migration, Nicholas B. Gallo

University Scholar Projects

Adult neurogenesis, the process of generating new neurons from neural precursors, is a highly complex process that is limited to two specific areas of the brain, the dentate gyrus of the hippocampus and the subventricular zone (SVZ). Despite continued research investigating neurogenesis in these two regions, we still lack a fundamental understanding of the molecular mechanisms of neural cell division, migration, differentiation, and integration in the postnatal brain. In particular, the rostral migratory stream (RMS), which is a cellular migratory route for newly generated neuronal precursors that travel from the SVZ to the olfactory bulb, will provide a useful model …

Astroglial Boundary Formation And Epha4 Signaling In Neuroblast Migration, Nicholas B. Gallo

Honors Scholar Theses

Adult neurogenesis, the process of generating new neurons from neural precursors, is a highly complex process that is limited to two specific areas of the brain, the dentate gyrus of the hippocampus and the subventricular zone (SVZ). Despite continued research investigating neurogenesis in these two regions, we still lack a fundamental understanding of the molecular mechanisms of neural cell division, migration, differentiation, and integration in the postnatal brain. In particular, the rostral migratory stream (RMS), which is a cellular migratory route for newly generated neuronal precursors that travel from the SVZ to the olfactory bulb, will provide a useful model …

Characterization Of The Ependymal Barrier Due To Human Aging And Injury In Murine Models, Ye Sun

University Scholar Projects

Ventriclulomegaly, or the expansion of the ventricles in the brain, is a phenomenon associated with age and injury to the brain. The ependymal layer that encases the ventricles displays certain degrees of plasticity and regenerative ability due to its associated stem cell niche, the subventricular zone (SVZ). Previous research in the Conover Lab has shown that in the mouse, which maintains an actively proliferating SVZ into adulthood, there is an intact ependymal monolayer throughout normal aging, with maintained lateral ventricle size with some degree of stretching. In contrast, the human SVZ declines in proliferative capacity after infancy, and age-related changes …

The Effect Of Repeated Mild Traumatic Brain Injury On Ventricular Volume And Microglial Activation, Lillian Rose Talbot

Honors Scholar Theses

As the leading cause of death and disability in individuals under the age of 45-years-old, Traumatic Brain Injury (TBI) is a public health crisis that demands the attention of the scientific and medical community [28]. The majority of all TBIs that occur in the United States each year are a non-deadly yet detrimental form of closed brain injury known as mild TBI (mTBI) or concussion [6]. Athletes, young people and military personnel all face a high risk of acquiring mTBI as a result of their environments. In our study we have chosen to model repeated mTBI (rmTBI) in the mouse …

Modulation Of Synaptic Transmission By Adenosine In Layer 2/3 Of The Rat Visual Cortex In Vitro, Nicholas M. Bannon

Master's Theses

No abstract provided.

Evidence For Pit-Type (Slc20) And Napi-Ii-Type (Slc34) Transporters In The Rat Choroid Plexus, Hien M. Le

Honors Scholar Theses

: A major function of the brain choroid plexus (CP) is to regulate the exchange of solutes between the blood plasma and the cerebrospinal fluid (CSF) using selective transporters. CSF inorganic phosphate (P_i) concentration is maintained at about one-half that of plasma and is potentially important because of its regulatory, structural, and biochemical functions. Phosphate is critical for ATP and DNA formation, the linked regulation between phosphate and calcium, and as an intracellular buffer. The human body has two major P_i transporter gene families known as SLC34 (NaPi-II) and SLC20 (PiT), which have wide tissue distribution. Although …

Detection Of Sk2 Channels On Hippocampal Neurons, Jamie L. Maciaszek

Master's Theses

Calcium-activated small conductance potassium channels (SK) are crucial for synaptic plasticity, sleep, and learning and memory (Hammond, Bond et al. 2006; Cueni, Canepari et al. 2008; Lin, Lujan et al. 2008). Despite the recent progress on SK channel physiology, the precise spatial organization of SK channels in neurons has remained unknown. Such knowledge is critical as the subcellular distribution of SK channels is an important determinant of neuronal excitability. Currently, there are no techniques to image ion channel distribution quantitatively at the nanometer scale in living cells. Here, it is demonstrated that integration of natural toxins with single molecule atomic …

Investigation Of Mirnas Expression In A Citron-Kinase Mutant Model Of Microcephaly, Shan Parikh

Master's Theses

Mutation of Citron-Kinase (Cit-K) in rodents causes substantial reductions in the number of neurons generated in the CNS and results in a primary microcephaly-like phenotype. Evidence from drosophila genetics has further established a genetic link between Cit-K and a protein Argonaut 1 (AGO1), which is required for proper functioning of the miRNA machinery (2). Experiments characterizing the role of miRNAs in the developing cortex demonstrate the requirement of miRNAs for differentiation of neural progenitor cells starting at embryonic day 12.5 (3). Together, this evidence links the role of miRNAs to neurogenesis and thus this relationship warrants further investigation. Here miRNA …

Modulation Of Hypoglossal Motoneurons By Nitric Oxide, Justin Philip Benoit

Master's Theses

Obstructive sleep apnea (OSA)- the occurrence of repetitive episodes of airway obstruction during sleep- is considered a major health problem affecting up to 9% of adults in the United States (Parish & Somers, 2004). The hypoglossal motor nucleus (HMN) controls genioglossus muscle tone and is critically important for maintaining airway patency; loss of excitatory input to the HMN during sleep results in disfacilitation of hypoglossal motoneurons, increased airway resistance and contributes to the development of OSA (Horner R. L., 2007). However, a fundamental question of sleep medicine that remains unresolved is what mechanisms help maintain airway patency during sleep? A …

Dopaminergic Innervation Of The Subventricular Zone In The Murine Brain, Linda Beth Drozdowicz

Honors Scholar Theses

The subventricular zone (SVZ) is one of two areas in the brain that, in a healthy mouse, continually generate neurons throughout adulthood. While it was previously thought that only the A9 neurons of the substantia nigra sent dopaminergic afferents to the SVZ, recent studies suggest that the A10 neurons of the ventral tegmental area may innervate this area. This project has aimed to discover which, if either, model is correct.

Examination of the Aphakia (AK) mouse was used to determine the role of distinct midbrain regions in SVZ regulation. Additionally, intraperitoneal injections of the chemical MPTP were used to deduce …