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Acetylation Regulates Thioredoxin Reductase Activity And Oligomerization, David E. Wright

Electronic Thesis and Dissertation Repository

The Thioredoxin (Trx) system provides the cell with robust defense against oxidative stress and regulates the function of nearly every cellular process through the reduction-oxidation (redox) regulation of proteins. The Trx system is involved in the development of many diseases ranging from cancer to cardiovascular disorders. Thioredoxin reductase (TrxR) is the key enzyme in the Trx system and contains the 21^st genetically encoded amino acid, selenocysteine (Sec). There were multiple experimentally identified TrxR acetylation sites with an unknown effect on TrxR activity. My thesis tested the hypothesis that programmed protein acetylation will enhance the activity of TrxR1. I used …

The Protective Effects Of Anthocyanins On Neurons, Abigail Lynn

Pence-Boyce STEM Student Scholarship

Parkinson’s and Alzheimer’s are debilitating neurodegenerative diseases that are largely thought to be exacerbated, and perhaps even caused, by oxidative stress in and around neurons. At the same time, there has been increased research in the field of nutrition and how the foods we eat impact our short- and long-term health. These combined interests have resulted in fascinating studies that have found certain foods, namely plants, can have a variety of medicinal benefits.....The purpose of this study is to determine if plant extracts that have high levels of certain phytonutrients can increase the activity of cellular enzymes that reduce oxidative …

The Response Of Microcystis And The Microbiome To Exogenous Hydrogen Peroxide, Bryan A. Puma

Masters Theses, 2020-current

Microcystis spp. produce prolific annual blooms in freshwater systems worldwide. The success of these blooms depends heavily on the Microcystis spp. overcoming environmental factors such as oxidative stress caused by reactive oxygen species (ROS) like hydrogen peroxide. Most Microcystis genomes do not contain many genes for responding to oxidative stress, including those that encode the enzyme catalase. Other cyanobacteria such as Prochlorococcus that also lack hydrogen peroxide degrading enzymes have been shown to benefit from partnerships with heterotrophic bacteria. Microcystis spp. may also receive similar benefits from heterotrophic bacteria in the phycosphere. To test this hypothesis, we examined the …

Thermal Tolerance, Physiology, And Microhabitat Use Of Eleutherodactylus Coqui Across An Elevational Gradient In Hawai‘I, Jack Marchetti

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The coqui frog (Eleutherodactylus coqui) is an invasive species in Hawai‘i, and has spread across much of the island. While elevational temperature differences are thought to restrict the coqui’s spread, it is unclear if they have resulted in changes to the coqui’s physiology and microhabitat use as it has expanded into higher elevations.

We first sought to determine if the coqui’s substrate use and baseline physiology differs between elevations. We found that frogs at high elevation were found closer to the forest floor and used different substrates than frogs from low and mid-elevations. This change in microhabitat use …

Effect Of Elevated Temperature And Roundup Exposure On Oxidative Stress And Antioxidant Status In The American Oyster, Afsana Chowdhury

Theses and Dissertations

Aquatic organisms are frequently exposed to various environmental stressors. In this study, we observed the short-term (1-week) combined dose-dependent effect of Roundup, a glyphosate-based herbicide, and high temperature (30°C) on the morphology of gills and digestive glands, expression of heat shock protein-70 (HSP70), dinitrophenyl protein (DNP), nitrotyrosine protein (NTP), antioxidant enzymes such as catalase (CAT) and superoxidase dismutase (SOD) in tissues of American oyster (Crassostrea virginica). Histological analyses showed an increase in mucous production in the gills and digestive glands, hemocyte aggregation in the connective tissues as well as structural change of the lumen in the digestive glands …

Examining The Oxidative Stress Effects In Rats Exposed To 2-Aminoanthracene In Utero And High Fat Diet Three Months After, Brianna A. Lanoix

Honors College Theses

Polycyclic aromatic hydrocarbons are organic compounds that are created synthetically or found in partially burned oil, gasoline, and coal. 2-aminoanthracene (2AA) is a common example of a PAH and can affect lipid and carbohydrate metabolism and resulting in inflammatory problems and oxidative stress. The objective of the research project is to investigate oxidative stress in relation to diabetes in rats exposed to 2AA in utero and a high fat diet later in life. Pregnant dams were separated into treatment groups based on their dosages of 2AA; 0 mg/kg (control), 50 mg/kg (low), 100 mg/kg (high). During the gestation -postpartum period, …

Cytotoxicity Of Copper (Ii) Octanoate On Mouse Hippocampal Astrocytes, Ali A. Shohatee

Theses and Dissertations

Copper, as an essential trace element, is crucial for various biological processes but has also been utilized as a constituent of various pesticides for decades. Copper (II) octanoate is a pesticide utilized as a fungicide and is approved for use in the production of certified organic foods. Previous studies have implicated copper as an inducer of oxidative stress and activator of the Nrf2-ARE pathway. Nrf2 is essential in regulating the transcription of various genes to alleviate toxicity such as those involved in glutathione synthesis and detoxification. Due to the limited toxicological data, this study into the potential induction of oxidative …

Endogenous Antioxidant Response And Lipid Peroxidation Levels In Muscle Tissue Of The Cownose Ray (Rhinoptera Bonasus), Bailey Berry

Electronic Theses and Dissertations

Oxidative stress is the result of an imbalance between reactive oxygen species (ROS) and antioxidant response within cells. ROS generation is a natural consequence of ETC activity within the mitochondria and is associated with aerobic metabolism. Oxidative stress data on elasmobranch muscle is limited, with previous studies primarily focusing on mammalian and teleost muscle. Elasmobranch skeletal muscle is generally composed of large proportions of white muscle fibers (anaerobic), low proportions of red muscle fibers (aerobic), and low proportions of pink muscle fibers (anaerobic). The cownose ray, a benthopelagic batoid species, presents an interesting model of study because it contains relatively …

Effects Of Roundup Exposure On Redox Status, Cellular Apoptosis, And Antioxidant And Osmoregulatory Enzyme Expressions In Goldfish (Carassius Auratus), Md Imran Noor

Theses and Dissertations

Intense anthropogenic activities of industrialized nations dramatically increase environmental pollution. This study focused on the effects of Roundup, a glyphosate-based herbicide, exposure (low- and high-dose: 0.5 and 5 mg/L for 2 weeks) on dinitrophenyl protein (DNP), nitrotyrosine protein (NTP), superoxidase dismutase (SOD), catalase (CAT), Na+ /K+ - ATPase (NKA), and renin expressions, and cellular apoptosis in the gills and kidneys of goldfish. Histopathological analysis showed widespread tissue damage in both gills and kidneys. Immunohistochemical analysis provided insights into the expression of molecular biomarkers in tissues. Fish exposed to Roundup exhibited a significant (P<0.05) upregulation in DNP, NTP, SOD, and CAT expressions, and apoptotic nuclei in both tissues. Additionally, exposure to Roundup significantly increased renin expression in kidneys and decreased NKA expression in gills. Overall, our results suggest that exposure to Roundup induces oxidative/nitrative stress and cellular apoptosis and alters osmoregulatory and antioxidant systems which may lead to impaired physiological functions in goldfish.

Redox Sensing By Yeast Hsp70 Facilitates Modulation Of Protein Quality Control And The Cytoprotective Response, Alec Santiago

Dissertations & Theses (Open Access)

Neurodegenerative disease affects millions of Americans every year, through diagnoses such as Alzheimer’s, Parkinson’s, and Huntington’s diseases. One factor linked to formation of these aggregates is damage sustained to proteins by oxidative stress. Cellular protein homeostasis (proteostasis) relies on the ubiquitous Hsp70 chaperone family. Hsp70 activity has been previously shown to be modulated by modification of two key cysteines in the ATPase domain by oxidizing or thiol-modifying compounds. To investigate the biological consequences of cysteine modification on the Hsp70 Ssa1 in budding yeast, I generated cysteine null (cysteine to serine) and oxidomimetic (cysteine to aspartic acid) mutant variants of both …

Roles Of Oxidative Stress And Dna Methylation In Cigarette Smoking-Induced Accelerated Acute Myeloid Leukemia Progression, Mary Figueroa

Dissertations & Theses (Open Access)

Acute myeloid leukemia (AML) is a commonly diagnosed cancer in smokers. When current or former smokers have AML, they have worse survival compared to never smoking patients. This has been observed clinically for decades, but then it is unknown how smoking leads to worsened AML survival. Smoking causes oxidative stress and altered DNA methylation that persists for decades in peripheral blood mononuclear cells, but these changes from smoking have not been evaluated in the context of AML. We hypothesize that smoking-induced molecular changes, including altered DNA methylation associated with poor AML prognosis, promote AML. We developed a novel model to …

The Effect Of Media And Filtration In Inducing The Oxidative Stress Response In Escherichia Coli, Suzanne Hollingsworth

University Honors Theses

Escherichia coli grown in complex medium (LB), but not defined medium (DGC), arrest DNA replication when collected on membrane filters and resuspended in fresh media. The arrest is similar to that observed when cells are challenged with hydrogen peroxide. Yet, the reason behind this arrest is unknown.

I hypothesized that the arrest in replication in complex medium after filtering might be due to oxidative shock, and therefore cells grown in complex medium and filtered should induce an oxidative stress response similar to cells treated with hydrogen peroxide. Utilizing the indicator dye H₂DCFDA, which fluoresces in response to reactive …

Repeated Low-Level Blast Induces Chronic Neuroinflammation And Neurobehavioral Changes In Rat Models, Arun Reddy Ravula

Dissertations

Blast-induced neurotrauma (bTBI) is a signature medical concern for military personnel when they are exposed to explosions in active combat zones. However, soldiers as well as law enforcement personnel are also repeatedly exposed to low-level blasts during training sessions with heavy weaponries as part of combat readiness. Service personnel who sustain brain injuries from repeated low-level blasts (rLLBs) do not display overt pathological symptoms immediately but rather develop cognitive impairments, attention deficits, anxiety, and sleep disturbances over time. An improved rat model of rLLB was developed in this thesis by applying controlled low-level blast pressures (10 psi) repeated five times …

Investigating The Roles Of Rna Modification And Associated Enzymes On Stress Response And Connections To Human Diseases, Carrson Widen

Biological Sciences

Transfer RNAs decode messenger RNA using anticodon – codon interactions to deliver specific amino acids to a growing peptide chain. Enzyme-catalyzed modifications on specific nucleotides on tRNAs increase their stability and help mediate the speed and fidelity of translation, giving these modifications regulatory potential. RNA modifications are catalyzed by writer enzymes, and I predicted that writers are important in the cellular responses to stress. I have evaluated the following E. coli modification enzyme mutants: miaA, mnmE, dtd, tmcA, lysU, yeaK, and iscS, from the corresponding Keio E. coli gene deletion library. Writer mutants were exposed to hydrogen peroxide to induce …

Aging, A Pathological Factor In Neurological Injury, Aruvi Vijikumar

Graduate Theses, Dissertations, and Problem Reports

One of the main reasons for CNS drugs to fail in clinical development is not considering age as a risk factor while studying chronic age-related neurological/neurodegenerative diseases in preclinical studies. We first set out to gain a comprehensive understanding of the impact of age on various aspects (anatomical, immunological, and biochemical) in rodents that play a key role in determining the onset, progression, and evolution of disease severity. With advancing age, the vascular structure and function are compromised which is hypothesized to accelerate cognitive decline. The initial step toward developing novel therapeutics is to characterize the age-related vascular modifications. Utilizing …

Toxicity Of Indoor Dust-Derived Trace Elements And Organic Contaminants Impact On Normal Human Colon Epithelial Cells, Noura Abdulrahman

Theses (2016-Present)

Indoor dust stands out as a burgeoning challenge in society due to its implication on people’s health. Exposure to toxic dust particles occurs in different ways that include inhalation, ingestion, and dermal contact. In the hindsight, many people spend most of their time indoors exposing themselves to high levels of dust. Notably, different groups of individuals present varied risk levels to the toxicity of particles with vulnerable persons being susceptible to adverse effects of these contaminants. This includes the elderly, children, and immunocompromised individuals. The study examines the impacts of two variables that are trace elements (TMD) and organic contaminants …

Toxicity And Effects Of Tire Crumb Rubber In The Aquatic Environment, Stephanie Laplaca

All Dissertations

Plastic materials have provided innovative solutions to society’s evolving needs and challenges. Due to their durability and resistance to degradation, plastics remain in the environment for long periods of time and can therefore be transported to many environmental compartments such as water, sediment, and biota. Microplastics (MPs) have been defined as synthetic plastic particles that have at least one dimension less than 5 mm and are insoluble in water. Microrubber (MR), a recently acknowledged sub-group of MPs, has been documented in environmental samples more recently, frequently comprising a large portion of total MPs of various samples. In South Carolina specifically, …

Characterizing The Structural, Biophysical And Functional Effects Of S-Glutathionylation On Stim1 Ca2+ Sensing, Christian Michael Sirko

Electronic Thesis and Dissertation Repository

Stromal interaction molecule 1 (STIM1) is an endo/sarcoplasmic reticulum (ER/SR) calcium (Ca²⁺) sensing protein that initiates cytoplasmic Ca²⁺ influx via store-operated calcium entry (SOCE). STIM1, in conjunction with Orai, a plasma membrane (PM) protein, function as mediators of SOCE through the formation of calcium-release activated calcium (CRAC) channels. S-Glutathionylation of STIM1 at Cys56 has been shown to evoke constitutive Ca²⁺ entry in DT40 cells, however no studies have carefully investigated the biophysical and structural effects of this covalent modification to the luminal domain, which are critical for understanding the molecular mechanism underlying the regulation of …

Elucidating The Evolution And Function Of Srnas That Facilitate Bacterial Stress Tolerance, Madeline Claire Krieger

Dissertations and Theses

Non-coding small RNAs (sRNAs) are ubiquitous post-transcriptional regulators found in both gram-negative and gram-positive bacteria. Despite their integral role in many regulatory pathways, including those that facilitate stress-tolerance, little is known about the evolutionary forces that drive the emergence of novel sRNAs, how prevalent sRNAs are within bacterial species, or the functions of a majority of these transcripts. In this work, I first describe the evolution of OxyS, a well-characterized sRNA in gram-negative Enterobacteriaceae that is involved in coordinating the bacterial response to oxidative stress. Next, I identify novel sRNAs differentially produced by the gram-positive oral pathogen Streptococcus mutans in …

Synthetic Heterosynaptic Plasticity Enhances The Versatility Of Memristive Systems Emulating Bio-Synapse Structure And Function, William T. Mcclintic

Doctoral Dissertations

Memristive systems occur in nature and are hallmarked via pinched hysteresis, the difference in the forward and reverse pathways for a given phenomenon. For example, neurons of the human brain are composed of synapses which apply the properties of memristance for neuronal communication, learning, and memory consolidation. Modern technology has much to gain from the characteristics of memristive systems, including lower power operation, on-chip memory, and bio-inspired computing. What is more, a relationship between memristive systems and synaptic plasticity exists and can be investigated focusing on homosynaptic and heterosynaptic plasticity. Where homosynaptic plasticity applies to interactions between neurons at a …

Validation Of Anti-Oxidative Stress Genes From Genome-Wide Screening Of Escherichia Coli, Carson Ercanbrack

Chemistry & Biochemistry Undergraduate Honors Theses

The primary purpose of this project is to evaluate the genes that play a role in the oxidative stress response in Escherichia coli. In doing so, the entire genome of E. coli was subject to throughput in which individual genes were determined to have a role in the bacteria’s oxidative stress response. Moreover, this project focused on the validation of the genes that were able to pass the initial throughput stage. The genes were subject to two forms of validation. In the first validation technique, candidate genes were overexpressed and minimum inhibitory concentrations of hypochlorous acid were taken. Following, a …

Elucidating The Role Of The Msaabcr Operon In Persister Cells Formation And Stress Response In Staphylococcus Aureus, Shanti Pandey

Dissertations

Staphylococcus aureus is a major human pathogen that causes lethal systemic conditions such as infective endocarditis, osteomyelitis, sepsis and pneumonia. Chronic in nature, these diseases are often refractory to the antibiotic treatment. Such recalcitrance is mainly caused due to the presence of persister cells, which are a bacterial subpopulation that exhibits extreme, yet transient antibiotic tolerance accompanied by a transient halt in the growth. However, upon cessation of antibiotic treatment, resumption in growth of persister cells causes recurrence of infections and treatment failure, displaying tremendous clinical significance. In this study, we show the involvement of the msaABCR operon in persister …

Antibacterial And Antioxidant Potential Of A Novel Plant, Eriodictyon Californicum, And Its Healing Abilities, Allie Richards

Undergraduate Theses

Our body is under constant attack of oxidative stress (OS). OS is a crucial factor in the pathogenesis and progression of various chronic diseases such as diabetics, rheumatoid arthritis, myocardial infarction, cardiovascular diseases, stroke, cancer, Alzheimer’s disease, Parkinson’s disease, aging and more. The main cause of OS is free radicals, which are continuously generated in our body during normal metabolic processes. These free radicals have the potential to damage any of our key biomolecules. To protect ourselves from the toxic effect of free radicals the human body has a built-in army of antioxidants that play an important role in the …

Herbal Extracts As Neuroprotective Agents In An In-Vitro Model Of Aluminum Neurotoxicity, Nada Ezzelarab

Theses and Dissertations

Background: Aluminum toxicity due to environmental or industrial exposure, medical applications, or from cooking utensils is a serious medical problem. The current study aims to investigate three herbal extracts: pomegranate peel extract, Achillea fragrantissima extract, and papaya fruit extract to combat this neurotoxicity.

Methods: Chemical characterization of the three extracts were evaluated using HPLC MS while their neuroprotective activity was assayed using MTT assay on SHSY5Y cells and nitric oxide levels.

Results: Using HPLC-MS chromatography, we have identified twenty-one compounds in the hydro-alcoholic Achillea fragrantissima, seventeen were determined in the pomegranate peel, eleven were assessed in the Carica papaya …

Nrf2 Regulation By Hsp90, Oxidation, And In Breast Cancer, Vy Ngo

Electronic Thesis and Dissertation Repository

To cope with the dynamic range of stressful stimuli that a cell experiences within its lifetime, a host of adaptive cell survival and cell stress response pathways have evolved. The antioxidant and heat shock responses are two key cell stress response pathways primarily involved in the detoxification and elimination of oxidative stress and the maintenance of protein integrity, respectively. Traditionally, these responses are regarded and studied as two independent pathways. In this exploratory work, we hypothesize that oxidative damage to Nrf2 and Keap1 and their interactions with Hsp90 alter their function within the cellular antioxidant stress response. By establishing and …

Effect Of Whole Fruit Based Anthocyanins On Systemic Inflammation, Oxidative Stress, And Waist Circumference In Women, Anastasiya Yudinova

Cal Poly Humboldt theses and projects

Cardiometabolic disease (CMD) remains the leading cause of death nationally. Intra-abdominal fat (IAF) is one of the primary risk factors for CMD. Women are particularly vulnerable to developing CMD due to hormonal changes during and after menopause that increase IAF. Excess IAF has deleterious effects on the body, increasing systemic inflammation and oxidative stress, leading to CMD. This systematic review and meta-analyses examined current research related to consumption of whole foods high in anthocyanins, their impact on oxidative stress and inflammation, and the medium and amount of anthocyanin delivery that yields the most benefits to women at risk for CMD. …

The Protective Effects Of Mir-210 Modified Endothelial Progenitor Cells Released Exosomes In Hypoxia/Reoxygenation Injured Neurons, Sri Meghana Yerrapragada

Browse all Theses and Dissertations

Endothelial progenitor cells (EPCs) have been shown to provide beneficial effects on oxidative stress. Exosomes (EXs) released from these stem cells could be one of the major contributors, as they are known to convey the benefit of one cell to another cell via microRNAs (miRNA). At first, we determined that EPCs release more EXs when they are serum-starved for 48 hours., and by determining the microRNA-210 (miR-210) levels in the EXs, we found that miRNA is being transferred from cells to EXs. Meanwhile, miR-210 is gaining popularity in reducing elevated oxidative stress levels. In this study, we investigated the role …

Interactive Effects Of Heat Stress And Pesticides Co-Exposure On Swimming Behavior, Oxidative Stress, Antioxidant Expression, And Redox Status In Common Goldfish (Carassius Auratus), Brittney Danielle Lacy

Theses and Dissertations

Aquatic ecosystems are inundated by environmental pesticides. This study, observed the dose-dependent effects of pesticides cocktail (metalachlor, linuron, isoproturon, tebucanazole, aclonifen, atrazine, pendimethalin, and azinphos-methyl) and elevated temperature (32 °C for 4-week exposure) on morphology of gills and kidneys, and expression of nitrotyrosine protein (NTP), dinitrophenyl protein (DNP), catalase (CAT), superoxidase dismutase (SOD), Na+/K+-ATPase, renin, and apoptosis in tissues of goldfish. Additionally, the effects on the free-swimming behavior were also observed. Histological analysis showed wide-spread damage in tissues at higher temperature and pesticides co-exposure. Immunohistochemical analysis demonstrated alterations in NTP, DNP, CAT and SOD expressions in tissues at higher temperature …

Therapeutic Potential Of A Ketogenic Diet In The Treatment Of Major Depressive Disorder, Jordan A. Murrin

Masters Theses, 2020-current

Major depressive disorder (MDD) is the second most common mental health condition and a leading cause of disability in the world. It is theorized that MDD develops from a combination of biological, psychological, and social stressors. The condition is typically treated using pharmaceuticals and psychotherapy. However, not all individuals with MDD have access to or choose to use these treatments, or may prefer to incorporate therapeutic lifestyle changes such as exercise, sleep, and healthy eating. Even with treatment, MDD can alter brain structure and function, leading to the development of comorbid mental health and chronic metabolic conditions like obesity, cardiovascular …

Impacts Of Tourism On The Ecophysiology Of The Endangered Northern Bahamian Rock Iguana (Cyclura Cychlura), Alison C. Webb

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Increased interest in ecotourism over recent years has led to more direct human-animal interactions and a striking concomitant increase in the provisioning of non-natural food, that may have unintended consequences for the wildlife involved. The critically endangered Northern Bahamian Rock Iguana provides a valuable model to address the potential impact of food provisioning on health as there are populations that represent a graded variation in human presence, with sites experiencing high, low, or no tourism. To assess the potential impacts of tourism on iguana physiology I first reviewed the relevant literature on iguana physiology and then performed three investigations focusing …