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Description
Neurological manifestations may be more prominent and have a larger role in ankylosing spondylitis than previously thought. Ankylosing Spondylitis is a rheumatic disease primarily identified by its autoinflammatory characteristics and is highly associated with the HLA-B27 gene. While it’s cause is not yet fully understood and it’s symptoms widely vary, neurological impairment is not uncommon. The neurological manifestations of Ankylosing Spondylitis include but are not limited to pain sensitization, altered brain phenotype, and disrupted cardiac conduction. Central and peripheral nervous system involvement may be more significant than previously thought and have the potential to cause demyelinating diseases, spinal cord, and nerve root injuries. Altered connectivity throughout various regions within the brain further exemplify the need for a better understanding of the disease and better treatment development. Higher instances of depression and dementia were also reported and coincide with not only a less active lifestyle, but altered brain activity. Studies on cardiac conduction and arrhythmias in AS patients revealed parasympathetic and sympathetic nervous system dysregulation. These studies have explored the possibility of new targets for treatment involving cardiac mechanisms. Treatments for diseases of a similar suspected pathology, new prospective targets for therapy, and a more thorough understanding of current treatments for the disease may be the key in providing more substantial relief. By further investigation in the role of the nervous system in Ankylosing Spondylitis, the disease may become more manageable for patients and greatly increase quality of life in the future.
ContributorsHill, Jordan (Author) / Newbern, Jason (Thesis director) / Anderson, Karen (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
As the incidence of dementia continues to rise, the need for an effective and non-invasive method of intervention has become increasingly imperative. Music therapy has exhibited these qualities in addition to relatively low implementation costs, therefore establishing itself as a promising means of therapeutic intervention. In this review, current research was investigated in order to determine its effectiveness and uncover the neurochemical mechanisms that lead to positive manifestations such as improved memory recall, increased social affiliation, increased motivation, and decreased anxiety. Music therapy has been found to improve several aspects of memory recall. One proposed mechanism involves temporal entrainment, during which the melodic structures present in music provide a framework for chunking information. Although entrainment's role in the treatment of motor defects has been thoroughly studied, its role in treating cognitive disorders is still relatively new. Musicians have also been shown to demonstrate extensive plastic changes; therefore, it is hypothesized that non-musicians may also glean some benefits from engaging in music. Social affiliation has been found to increase due to increases in endogenous oxytocin. Oxytocin has also been shown to strengthen hippocampal spike transmission, a promising outcome for Alzheimer's patients. An increase in motivation has also been found to occur due to music's ability to tap into the reward center of the brain. Dopaminergic transmission between the VTA, NAc and higher functioning regions such as the OFC and hypothalamus has been revealed. Additionally, relaxing music decreases stress levels and modifies associated autonomic processes, i.e. heart rate, blood pressure, and respiratory rate. On the contrary, stimulating music has been found to initiate sympathetic nervous system activity. This is thought to occur by either a reflexive brainstem response or stimulus interpretation by the amygdala.
ContributorsFlores, Catalina Nicole (Author) / Redding, Kevin (Thesis director) / Hoffer, Julie (Committee member) / Neisewander, Janet (Committee member) / School of Molecular Sciences (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Immediate early genes (IEGs) are rapidly activated in response to an environmental stimulus, and most code for transcription factors that mediate processes of synaptic plasticity, learning, and memory. EGR3, an immediate early gene transcription factor, is a mediator of biological processes that are disrupted in patients with schizophrenia (SCZ). A microarray experiment conducted by our lab revealed that Egr3 also regulates genes involved in DNA damage response. A recent study revealed that physiological neuronal activity results in the formation of DNA double-stranded breaks (DSBs) in the promoters of IEGs. Additionally, they showed that these DSBs are essential for inducing the expression of IEGs, and failure to repair these DSBs results in the persistent expression of IEGs. We hypothesize that Egr3 plays a role in repairing activity- induced DNA DSBs, and mice lacking Egr3 should have an abnormal accumulation of these DSBs. Before proceeding with that experiment, we conducted a preliminary investigation to determine if electroconvulsive stimulation (ECS) is a reliable method of inducing activity- dependent DNA damage, and to measure this DNA damage in three subregions of the hippocampus: CA1, CA3, and dentate gyrus (DG). We asked the question, are levels of DNA DSBs different between these hippocampal subregions in animals at baseline and following electroconvulsive stimulation (ECS)? To answer this question, we quantified γ-H2AX, a biomarker of DNA DSBs, in the hippocampal subregions of wildtype mice. Due to technical errors and small sample size, we were unable to substantiate our preliminary findings. Despite these shortcomings, our experimental design can be modified in future studies that investigate the role of Egr3 in activity-induced DNA damage repair.
ContributorsKhoshaba, Rami Samuel (Author) / Newbern, Jason (Thesis director) / Gallitano, Amelia (Committee member) / Marballi, Ketan (Committee member) / School of Molecular Sciences (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Damage to DNA can affect the genes it encodes; if this damage is not repaired, abnormal proteins may be produced and cellular functions may be disturbed. DNA damage has been implicated in the initiation and progression of a variety of diseases. Conversely, DNA damage has also been discovered to contribute to beneficial biological processes. Madabhushi and colleagues (2015) determined that activity-dependent DNA double strand breaks (DSBs) in the promoter region of immediate early genes (IEGs) induced their expression. EGR3 is an IEG transcription factor which regulates the expression of growth factors and synaptic plasticity-associated genes. In a previously conducted microarray experiment, it was revealed that EGR3 regulates the expression of genes associated with DNA repair such as Cenpa and Nr4a2. These findings inspired us to investigate if EGR3 affects DNA repair in vivo. Before conducting this experiment, we sought to standardize and optimize a method of inducing DNA damage in the hippocampus. Electroconvulsive stimulation (ECS) is utilized to induce neuronal activity. Since neuronal activity leads to the formation of DNA DSBs, we theorized that ECS could be used to induce DNA DSBs in the hippocampus. We predicted that mice that receive ECS would have more DNA DSBs than those that receive the sham treatment. Gamma H2AX, a biomarker for DNA damage, was utilized to quantify DNA DSBs. Gamma H2AX expression in the dentate gyrus, CA1 and CA3 regions of the hippocampus was compared between mice that received the sham treatment and mice that received ECS. Mice that received ECS were sacrificed either 1 or 2 hours post-administration, constituting treatment conditions of 1 hr post-ECS and 2 hrs post-ECS. Our results suggest that ECS has a statistically significant effect exclusively in the CA1 region of the hippocampus. However, our analyses may have been limited due to sample size. A power analysis was conducted, and the results suggest that a sample size of n=4 mice will be sufficient to detect significant differences across treatments in all three regions of the hippocampus. Ultimately, future studies with an increased sample size will need to be conducted to conclusively assess the use of ECS to induce DNA damage within the hippocampus.
ContributorsAden, Aisha Abubakar (Author) / Newbern, Jason (Thesis director) / Gallitano, Amelia (Thesis director) / Marballi, Ketan (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Aberrant signaling through the canonical RAS/RAF/MEK/ERK (ERK/MAPK) pathway leads to the pathology of a group of neurodevelopmental disorders called RASopathies. RASopathies are caused by germline mutations in the ERK/MAPK pathway and have an incidence of approximately 1:2000 births. The majority of RASopathies stem from mutations that cause gain-of-function in the ERK/MAPK pathway. In this study, we have begun to unravel the roles that GABAergic interneurons play in the pathology of RASopathies. Our data demonstrate that gain-of-function ERK/MAPK signaling expressed in a GABAergic interneuron-specific fashion leads to forebrain hyperexcitability in mutant mice. Further, some GABAergic interneurons experience activated-caspase 3 mediated apoptosis in the embryonic subpallium, leading to a loss of PV-expressing interneurons in the somatosensory cortex. We found that pharmaceutical intervention during embryogenesis using a MEK1 inhibitor may be effective in preventing apoptosis of these neurons. Future work is still needed to understand the mechanism of the death of GABAergic interneurons and to further pursue therapeutic approaches. Taken together, this study suggests potential roles of cortical GABAergic interneurons in ERK/MAPK-linked pathologies and indicates possible approaches to provide therapy for these conditions.
ContributorsShah, Shiv (Author) / Newbern, Jason (Thesis director) / Gipson-Reichardt, Cassandra (Committee member) / School of Life Sciences (Contributor) / Economics Program in CLAS (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Egr3 is an immediate early gene transcription factor that shows genetic association with schizophrenia, and is found in decreased levels in the brains of schizophrenia patients. Schizophrenia patients also exhibit cognitive and memory deficits, both of which Egr3 has been shown to play a crucial role in. Additionally, high levels of DNA damage are found in the brains of schizophrenia patients. A recent study has shown that DNA damage occurs as a result of normal physiological activity in neurons and is required for induction of gene expression of a subset of early response genes. Also, failure to repair this damage can lead to gene expression in a constitutive switched on state. Egr3 knockout (Egr3-/-) mice show deficits in hippocampal synaptic plasticity and memory. We were interested in characterizing downstream targets of EGR3 in the hippocampus. To determine these targets, electroconvulsive seizure (ECS) was carried out in Egr3 -/- versus wild type (WT) mice, and a microarray study was first done in our lab. ECS maximally stimulates Egr3 expression and we hypothesized that there would be gene targets that are differentially expressed between Egr3 -/- and WT mice that had been subjected to ECS. Two separate analyses of the microarray yielded 65 common genes that were determined as being differentially expressed between WT and Egr3 -/- mice after ECS. Further Ingenuity Pathway Analysis of these 65 genes indicated the Gadd45 signaling pathway to be the top canonical pathway, with the top four pathways all being associated with DNA damage or DNA repair. A literature survey was conducted for these 65 genes and their associated pathways, and 12 of the 65 genes were found to be involved in DNA damage response and/or DNA repair. Validation of differential expression was then conducted for each of the 12 genes, in both the original male cohort used for microarray studies and an additional female cohort of mice. 7 of these genes validated through quantitative real time PCR (qRT-PCR) in the original male cohort used for the microarray study, and 4 validated in both the original male cohort and an independent female cohort. Bioinformatics analysis yielded predicted EGR3 binding sites in promoters of these 12 genes, validating their role as potential transcription targets of EGR3. These data reveal EGR3 to be a novel regulator of DNA repair. Further studies will be needed to characterize the role of Egr3 in repairing DNA damage.
ContributorsBarkatullah, Arhem Fatima (Author) / Newbern, Jason (Thesis director) / Gallitano, Amelia (Committee member) / Marballi, Ketan (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
The mammalian target of rapamycin (mTOR) is integral in regulating cell growth as it maintains a homeostatic balance of proteins by modulating their synthesis and degradation. In the brain, mTOR regulates protein-driven neuroplastic changes that modulate learning and memory. Nevertheless, upregulation of mTOR can cause detrimental effect in spatial memory and synaptic plasticity. The proline-rich Akt-substrate 40 kDa (PRAS40) is a key negative regulator of mTOR, as it binds mTOR and directly reduces its activity. To investigate the role of PRAS40 on learning and memory, we generated a transgenic mouse model in which we used the tetracycline-off system to regulate the expression of PRAS40 specifically in neurons of the hippocampus. After induction, we found that mice overexpressing PRAS40 performed better than control mice in the Morris Water Maze behavioral test. We further show that the improvement in memory was associated with a decrease in mTOR signaling, an increase in dendritic spines in hippocampal pyramidal neurons, and an increase in the levels of brain-derived neurotrophic factor (BDNF), a neurotrophin necessary for learning and memory. This is the first evidence that shows that increasing PRAS40 in the mouse brain enhances learning and memory deficits.
ContributorsSarette, Patrick William (Author) / Oddo, Salvatore (Thesis director) / Caccamo, Antonella (Committee member) / Kelleher, Raymond (Committee member) / School of Molecular Sciences (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Okur-Chung Neurodevelopmental syndrome (OCNDS) is a rare disorder characterized by hypotonia, developmental delay, dysmorphic features, and more. It is caused by pathogenic variants on CSNK2A1, the α subunit of protein kinase CK2. CK2 is considered a master regulator involved in many cell functions from cell differentiation and proliferation to apoptosis. Here, we create a potential zebrafish model of OCNDS with CK2 inhibition and characterize fibroblast cells with, K198R, D156E, and R47G variants of CSNK2A1. RNAseq results display a wide range of effects notably in the Myosin Protein superfamily, Insulin-like Growth Factor family, and in proteins related to mitochondrial function and cell metabolism. Factors in cell growth and metabolism across the nervous system and neuromuscular interactions appear to be most affected with similarities in markers to oncogenic states in some cases.
ContributorsLeka, Kamawela (Author) / Newbern, Jason (Thesis director) / Rangasamy, Sampath (Committee member) / Barrett, The Honors College (Contributor) / School of Molecular Sciences (Contributor) / Harrington Bioengineering Program (Contributor)
Created2023-05
Description
The primary channel responsible for cold thermo-transduction in mammals is the transient receptor potential melastatin 8 (TRPM8) channel. TRPM8 is a polymodal, nonselective cation channel with an activation that is dependent on a variety of signals, including the membrane potential, calcium concentration, temperature, and ligands such as menthol. Mathematical modeling provides valuable insight into biochemical phenomena, such as the activity of these channels, which are difficult to observe experimentally. Here, we propose a TRPM8 gating model, represented as a system of ordinary differential equations with menthol, calcium, voltage, and temperature dependencies. We use voltage-clamp data from transfected HEK293 cells in the presence of menthol to create a menthol-dependent voltage shift of activation. We fit the parameters of the TRPM8 gating model to replicate experimental TRPM8 transfected HEK293 cell voltage clamp electrophysiology data using a genetic algorithm. Using k-means clustering, we note eight clusters within 110 total parameter sets consisting of parameter solutions that provide a good fit to the experimental data. We then replicate novel fixed-voltage temperature ramp and fixed-temperature voltage ramp experimental data, demonstrating that our model can replicate the dynamic behaviors of TRPM8. With this TRPM8 gating model, we analyze the various parameter sets obtained from the genetic algorithm and find that different parameter combinations of calcium decay, calcium voltage shift of activation, and temperature sensitivity are able to match static voltage clamp data although differ in their effects on hysteresis and maximal current within prolonged temperature ramp simulations.
ContributorsDudebout, Eric (Author) / Crook, Sharon (Thesis director) / Van Horn, Wade (Committee member) / Barrett, The Honors College (Contributor) / School of Molecular Sciences (Contributor)
Created2024-05