Developmental Neuroscience Commons^™

Individual Differences In Age And Testosterone Are Uniquely Associated With Neural Oscillatory Activity Serving Verbal Working Memory In Children And Adolescents, Abraham D. Killanin

Theses & Dissertations

During the sensitive period of adolescence, the human brain undergoes dynamic changes in structure and function resulting in vast executive function gains. Verbal working memory (VWM) is one executive function that serves as a foundation to language acquisition, reading, and learning. Many have examined the development of VWM in youth, but few have probed age-related changes in the underlying neural oscillatory dynamics, and none have examined testosterone-related changes. We recorded magnetoencephalography during a modified Sternberg VWM task in 82 youth participants aged 6 – 14 years old and collected salivary testosterone samples. Significant oscillatory responses were identified and imaged using …

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 …

Astrocytic Contribution To Sensory Hypersensitivity In A Mouse Model Of Fragile X Syndrome, Lara E. Bergdolt

Theses & Dissertations

Fragile X syndrome (FXS) is the most common form of inherited intellectual disability and a leading cause of autism spectrum disorder (ASD). FXS is caused by mutations in the fragile X mental retardation gene (FMR1), which result in complete or substantial loss of expression of its protein product fragile X mental retardation protein (FMRP). Neuronal impairments in the absence of FMRP have been extensively characterized. However, much less is known about the impact that loss of FMRP has on the physiology and function of astrocytes and the implications for behavior. A common behavior exhibited by both FXS and ASD patients …

Linking Spinal Cord Circuits With Upper Limb Sensorimotor Control In Adults With Cerebral Palsy, Saihari Dukkipati

Theses & Dissertations

Cerebral palsy (CP) is the most common neurological disorder originating in childhood, but most of the people living with CP are currently adults. While people with CP continue to get older, the amount of research focused on adults has been rather limited. The early childhood insults leading to CP are thought to originate in the brain, but the effects on the entire neuromuscular system across the lifespan have only recently started to be explored. Of note, recent neuroimaging evidence suggests that the cervical spinal cord structure is atypical in adults with CP. However, it is largely unclear how the neurophysiological …

Probing The Role Of Astrocytes In The Pathology Of Fragile X Syndrome With Human Stem Cells, Baiyan Ren

Theses & Dissertations

Fragile X syndrome (FXS) is an X-linked neurodevelopmental disorder related to intellectual disability and the most common monogenic cause of autism spectrum disorder. FXS is mainly caused by an expansion of CGG repeats in the 5’-untranslated region of fragile X mental retardation 1 (FMR1) gene, leading to the loss of expression of fragile X mental retardation protein (FMRP). Astrocytes are the most abundant glial cells in the central nervous system (CNS). Loss of FMRP in astrocytes has been found to contribute to structural and functional synaptic deficits in the Fmr1-KO mouse model. The contribution of human astrocytes, however, to the …

In Utero And Postnatal Oxycodone Exposure: Implications For Intergenerational Effects, Katherine E. Odegaard

Theses & Dissertations

Prescription opioid abuse during and after pregnancy is a rising public health concern. Adding a layer of complexity is the role of heredity in the overall development of these exposed offspring. The present work uses a preclinical rat model mimicking oxycodone (oxy) exposure in utero (IUO) and postnatally (PNO) to investigate comparative and intergenerational effects in the two different exposure groups.

To understand the direct effects of IUO and PNO exposure on the F1 generation, we employed a systems biology approach encompassing proton magnetic resonance spectroscopy (¹H-MRS), electrophysiology RNA-sequencing, and pain assessment to elucidate molecular and behavioral changes …

Molecular And Behavioral Studies In Cdkl5 Deficiency Disorder, Ethan Schroeder

Theses & Dissertations

CDKL5 Deficiency Disorder (CDD) is an X-linked neurodevelopmental disorder associated with epilepsy, developmental retardation, autism, and related phenotypes. Currently, there is no cure available for the disorder. Thus, the identification of cellular and molecular aberrations in this disorder and the generation and validation of mouse models that recapitulate core aspects of the disorder are a pressing need in the field. Our studies are aimed at filling this gap.

Mutations in the CDKL5 gene, encoding CDKL5, have been identified in this disorder. CDKL5 is a protein with homology to the serine-threonine kinases and incompletely characterized function. Mutations in CDKL5 are predominately …

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 …

Arid1b And Macf1 In Murine Brain Development And Behavior, Jeffrey Jay Moffat

Theses & Dissertations

Intellectual disability (ID) and autism spectrum disorder (ASD) affect between one and three percent of the global population. These disorders represent a significant emotional and financial burden for affected individuals and their families. Treatment for these conditions remains limited because many of the key molecular factors and associated pathogenic mechanisms are still poorly understood.

In this report we examine two genes related to ASD and ID, AT-rich interactive domain-containing protein 1B (ARID1B) and Microtubule-actin crosslinking factor 1 (MACF1). ARID1B is a subunit of the mammalian BRG1/BRM associated factor (BAF) chromatin-remodeling complex, which broadly regulates gene expression. ARID1B also …

A Role For Δ-Catenin In Synaptic Regulation, Li Yuan

Theses & Dissertations

The cadherin-catenin complex regulates cell-cell adhesion and signal transduction in epithelial cells. It is becoming increasingly evident that components of the complex regulate various aspects of neuronal architecture and function. δ-catenin is a cytosolic component of the cadherin-catenin complex and is predominantly expressed in the central nervous system. Loss of CTNND2, which encodes δ-catenin, is associated with intellectual disability and mutations in CTNND2 have been identified in autism, suggesting that δ-catenin is a critical component of the molecular machinery underlying neural circuit function. We have previously demonstrated that δ-catenin regulates multiple aspects of synaptic and dendritic development, including dendritic …

Compensatory Mechanisms And T Cell Migration In Mouse Models Of Dopaminergic Loss, Kristi M. Anderson

Theses & Dissertations

Parkinson’s disease (PD) is the most common neurodegenerative movement disorder and second most common neurodegenerative disorder. PD is characterized by the selective loss of dopaminergic neurons and dopamine neurotransmitter within the substantia nigra and termini in the striatum. Progressive loss of dopaminergic neurons occurs over many years in PD, and by the time movement disorder symptoms manifest, up to 50-70% of dopaminergic neurons have been lost. Several aspects of PD pathology have been described in detail, but a better understanding of PD progression is needed to develop more efficient treatments.

Motor symptoms associated with PD do not manifest until significant …