Neuroscience and Neurobiology Commons^™

Investigating The Neuroprotective Effects Of Cannabinoids And Insulin-Like Growth Factors On Glia With Induced Inflammation, Caleb Bloodworth

Honors Theses

Chronic inflammation is a driver of numerous neurodegenerative diseases that reduce quality of life for affected individuals. Non-psychoactive cannabinoids have begun to gain more interest in the world of anti-inflammatory medicine for chronically ill patients. Along with these cannabinoids, insulin-like growth factor-1 has been examined for its association with downregulation of inflammation. Our research aimed to investigate how neuroglia are affected by treatment with cannabinoids or IGF-1 in the face of inflammation from HIV-1 protein, Tat, or lipopolysaccharide (LPS). Preliminary studies in our laboratory showed that neither cannabinoids or IGF-1 treatment altered astrocyte morphology or overall astrocyte viability under baseline …

Hdac6 Inhibition Reverses Long-Term Doxorubicin-Induced Cognitive Dysfunction By Restoring Microglia Homeostasis, Blake Mcalpin

Dissertations and Theses (Open Access)

One in 8 women in the US will be diagnosed with breast cancer. Currently, doxorubicin is one of the most effective chemotherapies for breast cancer. Unfortunately, up to 60% of survivors report long-term chemotherapy-induced cognitive dysfunction (CICD) characterized by deficits in working memory, processing speed, and executive functioning. Currently, no interventions for CICD have been approved by the US Food and Drug Administration. I show here that a 14-day treatment with a blood-brain barrier permeable histone deacetylase 6 (HDAC6) inhibitor successfully reverses long-term CICD following a therapeutic doxorubicin dosing schedule in female mice, as assessed by the puzzle box test …

Innate Lymphoid Cell Characterization And Ilc2s In Neuroinflammation In Aging And Sex Differences, Alexis Mobley, Alexis S. Mobley

Dissertations and Theses (Open Access)

Aging affects immunologic responses by a global immune system suppression, including dysregulation of cytokine mediators, leading to increased inflammation throughout all systems, termed inflammaging. However, understanding healthy aging mechanisms can bypass this effect. Inflammaging also leads to poor outcomes during brain injury, making immune-targeting therapeutics tantamount to overall brain health and longevity. Moreover, sex affects disease etiology and severity through hormonal and chromosomal sex, as the X chromosome contains most immunology-based genes. Androgens have a generally suppressive effect on the immune system. Additionally, when immune responses are mounted, males are better at CD4+ T cell type (Th1) responses, while females …

Emerging Roles For The Orphan Gpcrs, Gpr37 And Gpr37 L1, In Stroke Pathophysiology, Sabra Mouhi, Breona Martin, Sharon Owino

Neuroscience: Faculty Publications

Recent studies have shed light on the diverse and complex roles of G-protein coupled receptors (GPCRs) in the pathophysiology of stroke. These receptors constitute a large family of seven transmembrane-spanning proteins that play an intricate role in cellular communication mechanisms which drive both tissue injury and repair following ischemic stroke. Orphan GPCRs represent a unique sub-class of GPCRs for which no natural ligands have been found. Interestingly, the majority of these receptors are expressed within the central nervous system where they represent a largely untapped resource for the treatment of neurological diseases. The focus of this review will thus be …

Application Of Confocal Microscopy To Study The Neural Mechanisms Underlying Insect And Rodent Behavior, Christian Michelle Harris

Theses, Dissertations and Capstones

Posture and walking require support of the body weight, which is thought to be detected by sensory receptors in the legs. Specificity in sensory encoding occurs through the morphological properties of the sense organs (numerical distribution, receptor size) and their physiological response characteristics. These studies focus upon campaniform sensilla, receptors that detect forces as strains in the insect exoskeleton. To study the morphology of campaniform sensilla, the sites of mechanotransduction (cuticular caps) were imaged by light and confocal microscopy in four species (stick insects, cockroaches, blow flies and Drosophila). These data indicate that the gradient (range) of cap sizes may …

Disruption Of Cholesterol Biosynthesis Contributes To Glial Dysfunction And Disturbs Astrocyte-Microglia Crosstalk, Bethany Ann Freel

Dissertations and Theses

The brain is the most cholesterol rich organ in the body, containing ~25% of the body’s total cholesterol content. Due to the blood-brain barrier, cholesterol in the brain is primarily synthesized de novo by astrocytes and transported to neurons. Genetic disorders of cholesterol biosynthetic enzymes result in reduced CNS cholesterol levels and sterol precursor accumulation. Smith-Lemli-Opitz syndrome (SLOS) is caused by mutations in 7-dehydrocholesterol reductase (DHCR7), which is responsible for the reduction of 7- DHC to cholesterol in the final step of the cholesterol biosynthesis pathway. SLOS results in broad neurodevelopmental malformations and neurological deficits. While much work has focused …

Microglia Polarize In Response To Transactive Response Dna-Binding Protein-43 (Tdp-43) And Display Partial Recovery After Removal Of The Stimulus, Alicen Wilcox

Honors Theses

The proper response to protein signals is necessary for a healthy central nervous system (CNS), and protein dysregulation is a feature of neurodegenerative diseases. Transactive response DNA-binding protein-43 (TDP-43) is an intranuclear protein, but mislocalization is associated with amyotrophic lateral sclerosis (ALS). TDP-43 is released into the extracellular space where it is sensed by microglia, the CNS-resident immune cells. Our data and the literature suggest that microglia respond to TDP-43 dysregulation by increasing CNS inflammation. The goal of this study was to determine the impact of TDP-43 on microglial function and the extent to which microglia recovery. To study the …

Alcohol As A Catalyst For Hiv-Associated Neuroinflammation And Tbi-Induced Iron Toxicity, Agnieszka Agas

Dissertations

Alcohol has long been considered an exacerbator of diseases, disorders, and injuries as well as many of the accompanying symptoms. As an alternative approach, this dissertation explores alcohol as a catalyst for two different human disease conditions, human immunodeficiency virus (HIV)-associated neuroinflammation and traumatic brain injury (TBI)-induced iron toxicity. In HIV-1 infection, this dissertation presents a novel anti-viral drug, called Drug-S, for a possible inhibition and treatment of HIV-1 disease progression.

The first aim explores the influence of alcohol with HIV-associated neuroinflammation on macrophage migration across an in vitro model of the blood brain barrier. There is a gap in …

Cognitive Changes Caused By Lps-Induced Neuroinflammation, Nancy De La Torre

Dissertations, Theses, and Capstone Projects

The brain performs cognitive processes finely orchestrated by timely precise action of neurons. Neurons functioning at their highest standard communicate with each other through perfectly functioning synapses. Microglia, as part of the immune system assist synaptic processing and have the ability to affect cognition. Indeed, microglia play a role in cognition. To investigate the link between microglia and cognition we utilized lipopolysaccharide (LPS) to pharmacologically activate microglia. LPS, normally present in the environment on the wall of Gram-negative bacteria is a pharmacological agent used to cause microglia activation in mice. LPS is a typical model to study changes induced by …

The Effects Of 17alpha-Hydroxyprogesterone Caproate On The Development Of The Mesocortical Dopamine Pathway And Cognitive Behavior, Melanie Lolier

Legacy Theses & Dissertations (2009 - 2024)

This dissertation examined the complex developmental impact of the clinically relevant synthetic progestin 17α-hydroxyprogesterone caproate (17-OHPC) on medial prefrontal cortex (mPFC) development. In rodents, the effects of 17-OHPC are subtle, but significant. In the Chapter II, we observed that 17-OHPC abolishes sex differences in dopaminergic fiber innervation and alters microglia phenotype in the prelimbic and infralimbic areas by the end of the first postnatal week. In the third chapter, the overall effect of 17-OHPC on the ontogeny of dopaminergic fiber innervation and synaptic bouton density were used to characterize the timing and duration of treatment effects in the mPFC. In …

Myelin, Cpla2, And Azithromycin: Modulation Of Macrophage Activation In Spinal Cord Injury Inflammation, Timothy J. Kopper

Theses and Dissertations--Physiology

Spinal cord injury (SCI) produces a chronic inflammatory state primarily mediated by macrophages consisting of resident microglia and infiltrating monocytes. These chronically activated SCI macrophages adopt a pro-inflammatory, pathological state that continues to cause additional damage after the initial injury and inhibits recovery. While the roles of macrophages in SCI pathophysiology are well documented, the factors contributing to this maladaptive response are poorly understood. Here, we identify the detrimental effects of myelin debris on macrophage physiology and demonstrate a novel, activation state-dependent role for cytosolic phospholipase-A2 (cPLA₂) in myelin- mediated potentiation of pro-inflammatory macrophage activation. Macrophage- mediated inflammatory …

The Role Of Anti-Inflammatory Cytokine Interleukin-10 (Il-10) In Tauopathies, Lea L. Weston

Biomedical Sciences ETDs

Tauopathies are neurodegenerative diseases, including Alzheimer’s disease, that are associated with pathological accumulation of the microtubule associated protein tau (MAPT, or tau) (Lee et al., 2001). Abnormal hyperphosphorylated tau (pTau) strongly correlate with cognitive impairment (Nelson et al., 2012). Neuroinflammation is also associated with tauopathies (Gerhard et al., 2006b; Edison et al., 2008) and is implicated in driving tau pathology (Yoshiyama et al., 2007, Maphis et al., 2015b). Therefore, it is compelling to understand the role of anti-inflammatory cytokines in limiting neuroinflammation and tau pathology. Interleukin-10 (IL-10) is a well-established anti-inflammatory cytokine with roles in limiting inflammation in the central …

Microglia Induced Neuroinflammation Through The Nlrp3 Inflammasome Following Blast Traumatic Brain Injury, Daniel Younger

Dissertations

The incidence of traumatic brain injury (TBI) among military personnel have been steadily increasing with modern conflicts. A recent RAND report estimated 320,000 service members, totaling 20% of deployed forces, suffer from TBI. However, of this population roughly 60% have not seen a medical professional specifically for TBI. Unlike the civilian population, the primary cause of TBI for active-duty military personnel is blast exposure. Blasts now account for over 70% of all US military casualties in operation Iraqi Freedom (OIF) and Operation enduring freedom (OEF) and are the major cause of TBI. Among many pathological mechanisms associated with blast TBI, …

Dha Modulates Manf And Trem2 Abundance, Enhances Neurogenesis, Reduces Infarct Size, And Improves Neurological Function After Experimental Ischemic Stroke, Ludmila Belayev, Sung Ha Hong, Raul S. Freitas, Hemant Menghani, Shawn J. Marcell, Larissa Khoutorova, Pranab K. Mukherjee, Madigan M. Reid, Reinaldo B. Oria, Nicolas G. Bazan

School of Medicine Faculty Publications

Aims: Mesencephalic astrocyte-derived neurotrophic factor (MANF) is a secretory neurotrophic factor protein that promotes repair after neuronal injury. The microglia cell surface receptor (triggering receptor expressed on myeloid cells-2; TREM2) regulates the production of pro- and antiinflammatory mediators after stroke. Here, we study MANF and TREM2 expression after middle cerebral artery occlusion (MCAo) and explore if docosahexaenoic acid (DHA) treatment exerts a potentiating effect. Methods: We used 2 hours of the MCAo model in rats and intravenously administered DHA or vehicle at 3 hours after the onset of MCAo. Neurobehavioral assessment was performed on days 1, 3, 7, and 14; …

Axonal Regrowth Of Olfactory Sensory Neurons After Chemical Ablation And Removal Of Axonal Debris By Microglia, Rudy Chapman

Electronic Theses and Dissertations

Olfactory sensory neurons (OSNs) are contained within the olfactory epithelium (OE) and are responsible for detecting odorant molecules in the air. The exposure of OSNs to the external environment is necessary for their function, but it also leaves them exposed to potentially harmful elements and thus results in a high turnover rate. Despite the high turnover, the olfactory sense is maintained throughout life through the division of a population of stem cells that produce new OSNs both during normal turnover and after an injury occurs in the OE. When new OSNs are born, they must extend axons from the OE …

Cytotoxic Analysis Of Old Drugs: New Drugs For Alzheimer’S Disease, Sebastian Yumiseba

Theses and Dissertations

Microglia are the resident immune cells of the CNS and constitute about 10% of all cells in the CNS. They have a vital role in Alzheimer’s pathogenesis as either cytotoxic or neuroprotective. Recent efforts are being put into repurposing drugs to target the microglia to treat Alzheimer’s disease.

Microglia-Neuron Interactions In A Mouse Model Of Low Grade Neuroepithelial Tumors, Veolette Hanna

Honors Scholar Theses

Microglia are the macrophages of the brain and spinal cord, playing an important role in the immune response to disease states of the nervous system. This study conducts an investigation on the activity of microglia in response to low grade neuroepithelial tumors. Using mouse models and microglial markers, a qualitative and quantitative analysis of microglia activation, migration, and invasion within the brain cortex during early stages of tumor development was conducted. It was found that the presence of a low grade neuroepithelial tumor in the cortex of one hemisphere of the brain causes significant microglia activation in comparison to the …

Effect Of Reduced Neurogenesis On Microglial Activation, Amelia Smith

Honors Scholars Collaborative Projects

The geriatric population of America has grown exponentially in the past century. Health degradations and expensive medical care are characteristic of this population with many of these costs due to age-related cognitive decline. It is essential to completely understand the mechanisms of normal and abnormal aging in the search for treatments for cognitive decline. A reduction of neurogenesis is a common factor in aging, but this reduction is even more drastic in individuals experiencing cognitive decline. It is unclear what effect reduced neurogenesis has on the extracellular environment, including glial cells. In particular, changes in microglial activation could be related …

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 …

Development And Sensory Experience Dependent Regulation Of Microglia In Barrel Cortex, Joshua C. Brumberg, John Kalambogias, Chia-Chien Chen, Safraz Khan, Titus Son, Carolyn Headlam, Cindy Lin

Publications and Research

The barrel cortex is within the primary somatosensory cortex of the rodent, and processes signals from the vibrissae. Much focus has been devoted to the function of neurons, more recently, the role of glial cells in the processing of sensory input has gained increasing interest. Microglia are the principal immune cells of the nervous system that survey and regulate the cellular constituents of the dynamic nervous system. We investigated the normal and disrupted development of microglia in barrel cortex by chronically depriving sensory signals via whisker trimming for the animals’ first postnatal month. Using immunohistochemistry to label microglia, we performed …

Determining The Pathological Effects Of Prenatal Alcohol Exposure On Peripheral Neuropathy Via Spinal And Peripheral Immune Mechanisms, Joshua J. Sanchez

Biomedical Sciences ETDs

Previous studies have suggested that children with Fetal Alcohol Spectrum Disorder (FASD) display hypersensitivity to light touch. In support of this notion, we have demonstrated that applying a chronic constriction injury (CCI) to the sciatic nerve of rats that have prenatal alcohol exposure (PAE) results in heightened sensitivity to light touch, clinically termed allodynia. These observations coincided with heightened glial activation and enhanced peripheral immune reactivity. Considering allodynia is known to be mediated by both peripheral immune responses and spinal glial activation, it is reasonable to speculate that allodynia following PAE may be mediated through an alteration of immune reactivity. …

Deletion Of P38Α Mapk In Microglia Blunts Trauma-Induced Inflammatory Responses In Mice, Josh M. Morganti, Danielle S. Goulding, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

Traumatic brain injury (TBI) is a significant cause of morbidity and mortality in the USA and other developed countries worldwide. Following the initial mechanical insult, the brain’s primary innate immune effector, microglia, initiate inflammatory signaling cascades and pathophysiological responses that can lead to chronic neuroinflammation and neurodegenerative sequelae. The p38α MAPK signaling pathway in microglia is a key contributor to inflammatory responses to diverse disease-relevant stressors and injury conditions. Therefore, we tested here whether microglia p38α contributes to acute and persistent inflammatory responses induced by a focal TBI. We generated conditional cell-specific knockout of p38α in microglia using a CX3CR1 …

Rejuvenation Of The Epigenetic Landscape Of The Aged Brain Through Manipulation Of Circulating Factors, Edward Koellhoffer

Dissertations and Theses (Open Access)

The aging population of the United States is expanding at an alarming rate. The Center for Disease Control and Prevention estimates that the population of those age 65 years and older will reach over 50 million by 2020 and will double to 100 million by 2060. This will not only put a massive strain on national healthcare resources, but will also increase the number of those who are not able to live and function independently. It is becoming increasingly vital to understand how the brain changes with age and mechanisms to possibly protect and rejuvenate the aged brain to a …

The Effects Of Two Novel Anti-Inflammatory Compounds On Prepulse Inhibition And Neural Microglia Cell Activation In A Rodent Model Of Schizophrenia, Heath W. Shelton

Electronic Theses and Dissertations

Recent studies have shown elevated neuroinflammation in a large subset of individuals diagnosed with schizophrenia. A pro-inflammatory cytokine, tumor necrosis factor-alpha (TNFα), has been directly linked to this neuroinflammation. This study examined the effects of two TNFα modulators (PD2024 and PD340) produced by our collaborators at P2D Bioscience, Inc., to alleviate auditory sensorimotor gating deficits and reduce microglial cell activation present in the polyinosinic:polycytidylic (Poly I:C) rodent model of schizophrenia. Auditory sensorimotor gating was assessed using prepulse inhibition and microglial activation was examined and quantified using immunohistochemistry and confocal microscopy, respectively. Both PD2024 and PD340 alleviated auditory sensorimotor gating deficits …

Induction Of Cerebral Hyperexcitability By Peripheral Viral Challenge: Role Of Cxcl10 Chemokine, Tiffany J. Petrisko

Graduate Theses, Dissertations, and Problem Reports (ETD)

Peripheral viral infections are po­tent comorbid factors that exacerbate neuro­degene­ration. Although the under­lying mecha­nisms have not been defined, neuronal hyperexcitability has been established as an underlying feature. Our lab has developed a preclinical model in which a viral mimetic, poly­inosinic-poly­cytidylic acid (PIC) is injected in­tra­peritoneally to induce an anti-viral acute phase response (APR). APR in turn elicits robust neuronal hyperexcitability. The present study was undertaken to characterize molecular mechanisms that mediate the development of hyperexcitability in response to PIC challenge. The analysis of brain tissue after PIC challenge revealed a robust elevation of CXCL10 chemokine, indicating its putative role in …

Mechanisms Of Microglia Mediated Apolipoprotien E Neurotoxicity, Pardeep Singh

Dissertations and Theses

No abstract provided.

Role Of The Fractalkine Receptor In Cns Autoimmune Inflammation: New Approach Utilizing A Mouse Model Expressing The Human Cx3cr1I249/M280 Variant, Sandra M. Cardona, Sangwon V. Kim, Kaira A. Church, Vanessa O. Torres, Ian A. Cleary, Andrew S. Mendiola, Stephen P. Saville, Stephanie S. Watowich, Jan Parker-Thornburg, Alejandro Soto-Ospina, Richard M. Ransohoff, Astrid E. Cardona

Peer Reviewed Articles

Multiple sclerosis (MS), an inflammatory demyelinating disease of the central nervous system (CNS) is the leading cause of non-traumatic neurological disability in young adults. Immune mediated destruction of myelin and oligodendrocytes is considered the primary pathology of MS, but progressive axonal loss is the major cause of neurological disability. In an effort to understand microglia function during CNS inflammation, our laboratory focuses on the fractalkine/CX3CR1 signaling as a regulator of microglia neurotoxicity in various models of neurodegeneration. Fractalkine (FKN) is a transmembrane chemokine expressed in the CNS by neurons and signals through its unique receptor CX3CR1 present in microglia. During …

Targeting Pro-Inflammatory Function Of Microglia Using Small Molecules To Combat Neurodegeneration, Gabrielle C. Williams, Priya Prakash, Gaurav Chopra

The Summer Undergraduate Research Fellowship (SURF) Symposium

Microglia are the brain’s resident immune cells that are responsible for maintaining homeostasis in healthy conditions. During injury or infection, resting microglia get activated and produce pro-inflammatory cytokines such as IL-1b, IL-1a, IL-6, etc. along with reactive oxygen species like nitric oxide (NO) to combat neuroinflammatory diseases such as Alzheimer’s disease (AD). Inflammation is characterized by the activation of resident-immune cells in the brain called microglia that respond to the eat-me signals released by the toxic amyloid beta peptides as well as the dying neurons in the microenvironment. Recent studies have shown that activated microglia induce neuronal death by secreting …

Ginsenoside Re Protects Methamphetamine-Induced Dopaminergic Neurotoxicity In Mice Via Upregulation Of Dynorphin-Mediated Κ-Opioid Receptor And Downregulation Of Substance P-Mediated Neurokinin 1 Receptor, Duy-Khanh Dang, Eun-Joo Shin, Dae-Joong Kim, Hai-Quyen Tran, Ji Hoon Jeong, Choon-Gon Jang, Seung-Yeol Nah, Jung Hwan Jeong, Jae Kyung Byun, Sung Kwon Ko, Guoying Bing, Jau-Shyong Hong, Hyoung-Chun Kim

Neuroscience Faculty Publications

Background: We previously reported that ginsenoside Re (GRe) attenuated against methamphetamine (MA)-induced neurotoxicity via anti-inflammatory and antioxidant potentials. We also demonstrated that dynorphin possesses anti-inflammatory and antioxidant potentials against dopaminergic loss, and that balance between dynorphin and substance P is important for dopaminergic neuroprotection. Thus, we examined whether GRe positively affects interactive modulation between dynorphin and substance P against MA neurotoxicity in mice.

Methods: We examined changes in dynorphin peptide level, prodynorphin mRNA, and substance P mRNA, substance P-immunoreactivity, homeostasis in enzymatic antioxidant system, oxidative parameter, microglial activation, and pro-apoptotic parameter after a neurotoxic dose of MA to clarify the …

Minocycline Protects Developing Brain Against Ethanol-Induced Damage, Xin Wang, Kai Zhang, Fanmuyi Yang, Zhenhua Ren, Mei Xu, Jacqueline A. Frank, Zun-Ji Ke, Jia Luo

Pharmacology and Nutritional Sciences Faculty Publications

Fetal alcohol spectrum disorders (FASD) are caused by ethanol exposure during the pregnancy and is the leading cause of mental retardation. Ethanol exposure during the development results in the loss of neurons in the developing brain, which may underlie many neurobehavioral deficits associated with FASD. It is important to understand the mechanisms underlying ethanol-induced neuronal loss and develop appropriate therapeutic strategies. One of the potential mechanisms involves neuroimmune activation. Using a third trimester equivalent mouse model of ethanol exposure, we demonstrated that ethanol induced a wide-spread neuroapoptosis, microglial activation, and neuroinflammation in C57BL/6 mice. Minocycline is an antibiotic that inhibits …