Cell and Developmental Biology Commons^™

From Chaos To Clockwork: Investigating The Role Of Circadian Genes In Metabolic Development Of 2nd And 3rd Instar Drosophila Larvae, Elliott R. Ruegsegger, Stephanie Hood, Amy Poe

Biological Sciences Undergraduate Honors Theses

Circadian clocks regulate daily physiological and metabolic rhythms across many organisms. In Drosophila melanogaster, the molecular clock involving period (per) and timeless regulates gene expression across 24-hour cycles. Circadian rhythms are well characterized in adult, mature organisms, but their emergence during early developmental stages remain poorly understood. In D. melanogaster, the circadian regulation of sleep and feeding rhythms emerges during the 3rd instar larval stage. This suggests that the circadian regulation of metabolism may also arise during this stage. Further, the metabolic consequences of circadian clock disruptions during this developmentally rich period remain unclear. This research aimed to …

Mitochondria Dynamics In Microglia During Health, Inflammation, And Aging, Alicia Nicole Pietramale

Dartmouth College Ph.D Dissertations

Microglia continually surveil the brain, allowing for rapid detection of tissue damage or infection. Microglial metabolism is linked to tissue homeostasis, yet how mitochondria are subcellularly partitioned in microglia and dynamically reorganize during surveillance, injury responses, and phagocytic engulfment in the intact brain has remained unclear. In this dissertation, I combine intravital imaging, ultrastructural analyses, and metabolic and cytoskeletal markers to investigate how mitochondrial organization relates to microglial function across health, inflammation, and aging.

I first show that microglial processes diverge in their mitochondrial content, with some containing multiple mitochondria while others are completely void. This heterogeneous partitioning is conserved …

Long Acting Beta2-Adrenergic Receptor Agonists Reverse Diabetic Nephropathy And Liver Steatosis In Murine Models Of Diabetes And Are Associated With Protection In Retrospective Human Studies, Brennan Winkler

MUSC Theses and Dissertations

Diabetes Mellitus (DM) affects 13.9% of men and 14.3% of women worldwide, a total of approximately 828 million people. Patients with diabetes are at risk of several complications including diabetic nephropathy (DN) and metabolic-associated steatohepatitis (MASH). These diseases eventually lead to end stage kidney disease (ESKD) and liver failure requiring dialysis and organ transplantation. In addition, diabetes exacerbates disease severity of autosomal dominant polycystic kidney disease (ADPKD), the most common potentially lethal genetic disease to affect humans with a prevalence of 1 in 500-1000. Therefore, a therapeutic approach that can attenuate organ damage and restore function in patients with DM, …

Brief Pulses Of High-Level Fluid Shear Stress Enhance Metastatic Potential And Rapidly Alter The Metabolism Of Cancer Cells, Amanda N. Pope, Devon L. Moose, Guy O. Hudson, Hank R. Weresh, Marion R. Dykstra, Aabha Y. Joshi, Patrick Breheny, Eric B. Taylor, Michael D. Henry

Department of Biomedical and Translational Sciences Faculty Publications

Circulating tumor cells (CTCs) face challenges to their survival, including mechanical and oxidative stresses that are different from cancer cells in solid primary and metastatic tumors. The impact of adaptations to the fluid microenvironment of the circulation on the outcome of the metastatic cascade is not well understood. Here, we find that cancer cells exposed to brief pulses of high-level fluid shear stress (FSS) exhibit enhanced invasiveness and anchorage-independent proliferation in vitro and enhanced metastatic colonization/tumor formation in vivo. Cancer cells exposed to FSS rapidly alter their metabolism in a manner that promotes survival by providing energy for cytoskeletal remodeling …

Investigating Potential Alzheimer's Disease Therapies Through An Agent-Based Model Of Impaired Microglia Metabolismmodeling Impaired Microglia Metabolism, Cheyenne Ty, Abigail Penland, John Gerving, Martin Mendoza-Ceja, Megan Pratt, Kamila Larripa

Spora: A Journal of Biomathematics

Alzheimer’s disease is the leading cause of dementia globally and is marked by amyloid-β plaque accumulation, decreased brain pH, disrupted metabolism, and increased permeability of the blood-brain barrier. Microglia, the resident immune cells of the central nervous system, are essential for maintaining brain homeostasis and are critically involved in the progression of AD. While microglia can initiate protective immune responses to injury and disease, dysregulated microglial metabolism may contribute to the exacerbation of Alzheimer's pathology. To investigate potential therapeutic strategies, we developed an agent-based model simulating the effects of exercise and metabolic enhancement on dysfunctional microglia. Our findings suggest that …

Impact Of S-Phase Kinase Protien 2 Blockades On Hematopoetic Stem Cell Metabolism, Nicole Elmaraghy

Electronic Theses, Projects, and Dissertations

Hematopoietic stem and progenitor cells (HSPCs) quiescence is vital for the success of bone marrow transplantation, as it preserves long term self- renewal and prevents premature exhaustion (Takubo et al., 2013; Wilson et al., 2008). However, bone marrow transplant (BMT) failure remains a clinical challenge, often due to lack of long-term engraftment and insufficient stress reliance. Both of these characteristics are tightly linked to disrupted stem cell quiescence and metabolic imbalance (Anso et al., 2017; Vannini et al., 2016). One key player is S-phase kinase protein (SKP2), an E3 ubiquitin ligase that targets cell cycle inhibitors, like p27, for proteosome …

Metabolic Regulation Of Cardiac Fibroblast Phenotype And Function., Collin Kleis Wells

Electronic Theses and Dissertations

Cardiac fibroblasts are central effectors of cardiac repair after myocardial infarction (MI). In response to signaling cues, they differentiate to a range of phenotypes with robust capacities to synthesize and secrete extracellular matrix (ECM) and signaling molecules. Although activated fibroblast phenotypes are associated with pronounced changes in metabolism, it remains unclear how the metabolic network upholds the effector functions of fibroblasts in the post-infarcted heart. Here, we identified that critical enzymes in the phosphoenolpyruvate (PEP) cycle, i.e. pyruvate kinase muscle-2 (PKM2) and phosphoenolpyruvate carboxykinase-2 (PCK2), are elevated in the heart after MI and examined their role in regulating post-MI remodeling …

The Role Of Ucp2 In Pancreatic Cancer Metabolism And Its Potential As A Radiosensitizer, Emily Rieff

Dissertations and Theses (Open Access)

Uncoupling protein 2 (UCP2) is a mitochondrial protein that regulates the flow of protons down the gradient established by the electron transport chain (ETC) without generating ATP, thus uncoupling the proton gradient from ATP generation. In tumors, specifically pancreatic cancer (PDAC), the ETC is highly stimulated to generate the copious ATP needed by the tumor to grow. However, extended ETC use increases reactive oxygen species (ROS), and if left unchecked, results in cell death. To evade this, PDAC employs antioxidant strategies, including upregulating UCP2 in tumor cells. In addition to its uncoupling function, UCP2 indirectly controls ROS levels by maintaining …

Steroid Receptors And Coregulators: Dissemination Of Sex Differences And Emerging Technologies, Sally Pauss, Evelyn A. Bates, Genesee J. Martinez, Zane T. Bates, Zachary A. Kipp, Cassandra D. Gipson, Terry D. Hinds Jr.

Markey Cancer Center Faculty Publications

Steroid receptors are ligand-induced transcription factors that have broad functions among all living animal species, ranging from control of sex differences, body weight, stress responses, and many others. Their binding to coregulator proteins is regulated by corepressors and coactivators that interchange upon stimulation with a ligand. Coregulator proteins are an imperative and understudied aspect of steroid receptor signaling. Here, we discuss steroid receptor basics from protein domain structures that allow them to interact with coregulators and other proteins, their essential functions as transcription factors, and other elemental protein–protein interactions. We deliberate about the mechanisms that coregulators control in steroid receptor …

Genetic Analysis Of Methionine Restriction-Associated Mitochondrial Unfolded Protein Response Signaling., Josh D. Dodge

Biology Dissertations - Archive

The lifespan of an organism is dictated by various genetic and environmental factors. One such determinant is the health of mitochondria which are organelles that mediate various critical cell functions including a significant role in generating the vast supply of cellular energy. Indeed, the gradual decline of mitochondrial function is believed to be a hallmark and possible cause of aging. Paradoxically, mild mitochondrial dysfunction early in life extends lifespan in various model organisms. Cells use diverse approaches to promote mitochondrial homeostasis, including the transcriptional reprogramming of cells by mitochondrial unfolded protein response (UPRmt) to mitigate mitochondrial stress. Consistently, UPRmt activation …

Characterizing And Targeting The Non-Catalytic Functions Of Phosphatase Of Regenerating Liver 3 (Prl-3) In Oncogenesis And Cancer Progression, Jeffery T. Jolly

Theses and Dissertations--Molecular and Cellular Biochemistry

Phosphatase of Regenerating Liver 3 (PRL-3) is frequently upregulated in various cancers and is associated with poor patient prognosis. Although traditionally studied for its phosphatase activity, PRL-3 also interacts with the CNNM family of magnesium transporters through its catalytic site, and these two functions are mutually exclusive at any given time. Most previous studies relied on a commonly used PRL-3 mutation that disrupts both phosphatase activity and CNNM binding, making it challenging to determine which function drives its oncogenic effects. To address this gap in the field, I utilized a panel of PRL-3 mutants that selectively disrupt either phosphatase activity …

Potentiation Of Gelonin Cytotoxicity By Pulsed Electric Fields, Olga N. Pakhomova, Eleni Zivla, Giedre Silkuniene, Mantas Silkunas, Andrei G. Pakhomov

Bioelectrics Publications

Gelonin is a ribosome-inactivating protein with extreme intracellular toxicity but poor permeation into cells. Targeted disruption of cell membranes to facilitate gelonin entry is explored for cancer and tissue ablation. We demonstrate a hundreds- to thousands-fold enhancement of gelonin cytotoxicity by pulsed electric fields in the T24, U-87, and CT26 cell lines. The effective gelonin concentration to kill 50% of cells (EC₅₀) after electroporation ranged from <1 nM to about 100 nM. For intact cells, the EC₅₀ was unattainable even at the highest gelonin concentration of 1000 nM, which reduced cell survival by only 5–15%. For isoeffective electroporation treatments using 300 ns, 9 µs, and 100 µs pulses, longer pulses were more efficient at lowering gelonin EC₅₀. Increasing the electric field strength of 8, 100 µs pulses from 0.65 to 1.25 kV/cm reduced gelonin EC₅₀ from 128 nM to 0.72 nM. Conversely, the presence of 100 nM gelonin enabled a more than 20-fold reduction in the number of pulses required for equivalent cell killing. Pulsed electric field-mediated delivery of gelonin shows promise for hyperplasia ablation at concentrations sufficiently low to minimize or avoid systemic toxicity.

Bridging The Gap Between Structural And Cellular Biology: Insight Into The Organization Of Glycolytic Enzymes In Cells, Heather Hansen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Glycolytic enzymes are spatially organized in the cytoplasm, and are shown to localize with cellular structures such as the plasma membrane, F-actin, mitochondria, or associate independently within the cytosol. The assembly of these enzymes is hypothesized to regulate pathway flux to meet the energetic needs of the cell. However, it is unclear whether all of these assemblies have the same mechanism of formation or function in the cell. We investigated the role of glycolytic enzyme assemblies in cells, using the glycolytic “gatekeeper” enzyme phosphofructokinase-1 (PFK1). PFK1 is extensively regulated by multiple mechanisms, including over 20 allosteric ligands, post translational modifications, …

Metabolic And Barrier Function In Response To Β-Caryophyllene In Intestinal Epithelial Cells, Hannah Scroggins

Theses and Dissertations--Animal and Food Sciences

Butyrate, a short-chain fatty acid, regulates cellular metabolism and energy status in intestinal epithelial cells. β-caryophyllene (BCP) is a plant-derived compound that may provide advantageous effects on intestinal barrier function and nutrient utilization. The goal of this thesis was to investigate the effects of BCP on butyrate utilization and metabolism in intestinal epithelial cells. Throughout this thesis, Caco-2 cells in hanging inserts in multi-well plates were used as a model for the intestinal barrier. One study was conducted to investigate the effect of BCP on butyrate utilization and barrier function in intestinal epithelial cells. A second study aimed to elucidate …

Accurate Body Weight Class Prediction From Mirna And Gene Expression In Blood And Saliva Samples, Kimberly Lettner

Master of Science in Forensic Science Directed Research Projects

miRNA interference on protein abundance related to glucose uptake and lipid production has been evaluated in biomedical research and linked to metabolic disorders like severe obesity. The direct regulation of protein abundance caused by miRNAs on a person’s metabolism can lead to an increased weight and overall size. Body size, measured by BMI, provides additional physical descriptions that can be combined with hair color, eye color, age, and skin pigment to aid investigations of unidentified remains or unknown suspects not found in a database. The purpose of this project was to evaluate the miRNA expression of target biomarkers in dried …

Functional And Structural Analysis Of The Neimann-Pick Disease Type C Pathway To Include Caveolin-1, Anthony Michael Seat

Chemistry and Chemical Biology ETDs

Human disease is often thought of as an all or nothing prospect, either one has the disease or one does not. This does not bear out in clinical or personal experiences, instead demonstrating that disease occurs within a spectrum ranging from presumed unaffected to demonstrably and detrimentally affected.Neimann-Pick disease is one example of this spectrum look into diseased states, with multiple named versions of a phenotypically similar disease. We focus on Neimann-Picktype C (NPC), which is the result of a disruption in the efflux of cholesterol and sphingolipids from the endocytic pathway. NPC demonstrates this concept of a spectrum of …

The Anti-Diabetic Drug Metformin Disrupts Feeding And Sleeping Behaviors In Drosophila Melanogaster., Lucas Fitzgerald

College of Arts & Sciences Senior Theses

Dimethylbiguanide, also known as metformin, is the single most prescribed oral treatment for non-insulin dependent diabetes mellitus, or type 2 diabetes, in Western countries. The primary mechanism of action that metformin acts through is the activation of AMP kinase, an important regulator of energy homeostasis. While the anti-diabetic effects of metformin are well documented, its effects on feeding and sleeping behaviors are not well characterized. Using the model organism Drosophila melanogaster, the mean daily quantity of food consumed was measured and compared between groups treated with several dosages of metformin. Feeding interactions such as meal frequency and length were …

Delineating Contributions Of Genotype And Lineage To Lung Cancer Therapy Response, Kassandra Jo Naughton

Theses and Dissertations--Toxicology and Cancer Biology

Non-small cell lung cancer (NSCLC) heterogeneity is a major challenge for determining effective treatment strategies. Adenocarcinomas (ADCs) and squamous cell carcinomas (SCCs) are histologically and epigenetically distinct subtypes of NSCLC. Patients with ADC tumors harboring mutations in both KRAS and LKB1 (aka STK11) have lower survival rates than those with KRAS-only tumors. KRAS/LKB1 tumors are not only aggressive, but also respond poorly to immunotherapy. However, these data are limited to ADCs, and it is unclear if SCCs with this genotype are also resistant to immunotherapy. We developed a mouse model of Kras^mut/Lkb1^mut capable of producing …

Identification And Therapeutic Targeting Of Metabolic Alterations In Estrogen Receptor-Positive Breast Cancer, Steven Tau

Dartmouth College Ph.D Dissertations

Estrogen receptor-positive breast cancer remains one of the most frequently diagnosed cancers in women. Despite adjuvant endocrine therapy reducing the rate of recurrence, there remains a significant proportion of patients whose breast cancer will recur years to decades after the initial diagnosis. The underlying biology of tumor cells in the period between initiation of adjuvant therapy and recurrence is relatively unexplored, preventing the development of better treatment options. From a genome-wide screening approach, we identified and characterized broad metabolic reprogramming associated with the persistent cell state. We demonstrate that a decreased ability to metabolize glucose in turn pushes a higher …

Development Of Combination Therapy Strategies To Treat Cancer Using Dihydroorotate Dehydrogenase Inhibitors, Nicholas Mullen

Theses & Dissertations

Cancer cells require supraphysiologic levels of nucleotide triphosphates to fuel their malignant behaviors, including uncontrolled proliferation, immune evasion, metastasis, and therapy resistance. This requirement is met by hyperactive flux through the de novo pyrimidine and de novo purine pathways. Dihydroorotate dehydrogenase (DHODH) is an essential enzyme in the de novo pyrimidine pathway that can be targeted by FDA approved and experimental drug compounds. A robust body of preclinical evidence, encompassing hundreds of independent studies over several decades, demonstrates impressive activity of DHODH inhibitors in animal models of cancer. Paradoxically, however, all clinical trials to date have failed to demonstrate efficacy …

Mitochondrial Roles In Developmentally Programmed Heart Disease, Eli John Louwagie

Dissertations and Theses

Offspring of diabetic and obese mothers (ODOM) have greater risks of heart disease at birth and later in life. However, prevention is hindered because underlying mechanisms are poorly understood. Mounting studies in the Developmental Origins of Health and Disease field suggest that mitochondria play key roles in developmentally programmed heart disease similar to the roles they play in cardiomyopathy in adults with diabetes and obesity. However, whether mitochondria are responsible for the short[1]and long-term cardiac disease seen in ODOM remains unknown. Here, we sought to delineate the roles of mitochondria in the hearts of ODOM, determine whether mitochondria are playing …

The Effects Of Sex On Zebrafish Bone Metabolism, Simon Bagatto

Williams Honors College, Honors Research Projects

I investigated the effects of diet and sex on zebrafish bone metabolism. Zebrafish were subjected to either a high-calorie or low-calorie diet over a five-week period. After this diet, zebrafish scales were used to measure alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) enzyme activity with a fluorescent substrate. The enzyme activities were markers of the osteoblasts (ALP) and the osteoclasts (TRAP). These data were compared among sex and diet of the zebrafish using a repeated measures ANOVA statistical test. I also measured the number of resorption lacunae per scale (another indicator of osteoclast activity). The results showed higher TRAP …

Exploring The Relationship Between The Epigenome And Metabolism In Mycn-Amplified Neuroblastoma, Krista M. Dalton

Theses and Dissertations

High risk neuroblastoma (NB) is responsible for nearly 15% of all cancer related deaths in the pediatric population. The transcription factor MYCN is the most studied oncogene in NB, automatically conferring high-risk and has been found to be difficult to target. One way that MYCN amplification in NB functions to support tumorigenicity is through altered metabolism, satisfying the demand for rapid proliferation by increasing the nutrient flux through biosynthetic pathways. We performed an unbiased screen on select metabolic targeted therapy combinations and correlated sensitivity with over 20 subsets of cancer. We found that MYCN-amplified NB is hypersensitive to the …

Ankyrin Dependent Mitochondrial Function And Bioenergetics In The Heart, Janani Subramaniam, Janani Subramaniam

Dissertations and Theses (Open Access)

ANK2 mutations in patients are associated with numerous arrhythmias, cardiomyopathies, and other heart defects. In the heart, AnkB, the protein encoded by ANK2, clusters relevant ion channels and cell adhesion molecules in several important domains; however, its role at Mitochondria Associated ER/SR Membranes (MAMs) has yet to be investigated. MAMs are crucial to mitochondrial function and metabolism and are signaling hubs implicated in various cardiac pathologies. Among several functions, these sites mediate the direct transfer of calcium from the ER/SR to the mitochondria to modulate ATP synthesis. Given that mitochondrial function and energy production are paramount to cardiovascular heath, …

A Computational Model Of The Line-1 Retrotransposon Life Cycle And Visualization Of Metabolic Networks In 3-Dimensions., Michael D. Martin

Electronic Theses and Dissertations

Computational modeling of metabolic reactions and cellular systems is evolving as a tool for quantitative prediction of metabolic parameters and reaction pathway analysis. In this work, the basics of computational cell biology are presented as well as a summary of physical processes within the cell, and the algorithmic methods used to find time dependent solutions. Protein-protein and enzyme-substrate interactions are mathematically represented via mass action kinetics to construct sets of linear differential equations that describe reaction rates and formation of protein complexes. Using mass action methods, examples of reaction networks and their solutions are presented within the Virtual Cell simulation …

Determining The Role Of Mir-133a In The Diabetic Heart, Tyler Kambis

Theses & Dissertations

Diabetes mellitus (DM) is characterized by hyperglycemia, hyperlipidemia, and hypoinsulemia, each of which disrupt intracellular mechanisms in the heart. DM is a chronic metabolic disease delineated into two categories: insulin deficient-type 1 DM and insulin resistant-type 2 DM. Although they differ in underlying genetic and physiological factors, both significantly increase the risk of heart failure. Impaired insulin signaling shifts energy dependency from glycolysis towards fatty acid β-oxidation in the DM heart. This DM-induced metabolic shift increases mitochondrial stress leading to mitochondrial dysfunction and cell death in the heart. The metabolically entwined ferroptosis is a novel form of myocardial cell death …

Metabolic Diversity Among Fibroblasts From Regenerating And Non-Regenerating Mammals, Ebenezer Aryee

Theses and Dissertations--Biology

Regeneration is a wound repair process that terminates in the restoration of tissue function and structure. Fibroblasts play pivotal roles in regenerative and fibrotic wound repair. Reports of extensive regenerative ability in mammals have been historically rare, but more recently spiny mice (Acomys) have emerged as a bona fide model of complex tissue regeneration. Recent work has indicated that fibroblasts from regenerators (Acomys and Oryctolagus) are more resistant to reactive oxygen species (ROS)-induced senescence compared to non-regenerating species, suggesting the influence of intrinsic cellular states on the fate of wound repair. Determining the basal metabolic signature …

Catabolism Of Bcaas And Application, Skylar Arellano-Myers

Honors Thesis

Over the past 150 years, amino acids have been found and researched in the nutrition biochemistry field. Over these years, three have been identified; leucine, valine and isoleucine; to make up the branch chain amino acids (BCAAs) that play a crucial role on the anaerobic and aerobic energy systems. The metabolism of BCAAs is a highly complicated process that is regulated by the activation of the alpha-keto acids dehydrogenase complex (BCKDH complex) to complete the catabolic reaction. With exercise, it has been found to increase the metabolism of BCAAs by increasing the BCKDH complex, which will decrease the fatigue and …

Investigating A Novel Function For Phosphoserine Aminotransferase 1 (Psat1) In Epidermal Growth Factor Receptor (Egfr)-Mediated Lung Tumorigenesis., Rumeysa Biyik-Sit

Electronic Theses and Dissertations

Phosphoserine aminotransferase 1 (PSAT1) catalyzes the second enzymatic step within the serine synthetic pathway (SSP) and its expression is elevated in numerous human cancers, including non-small cell lung cancer (NSCLC). Epidermal growth factor receptor (EGFR) mutant NSCLC is characterized by activating mutations within its tyrosine kinase domain and accounts for 17% of lung adenocarcinomas. Although elevated SSP activity has been observed in EGFR-mutant lung cancer cells, the involvement of PSAT1 in EGFR-mediated oncogenesis is still unclear. Here, we explore a putative non-canonical function for PSAT1 using biochemical approaches to elucidate unknown interacting proteins and genomic RNA-seq profiling to identify cellular …

In Vivo Optical Metabolic Imaging Of Long-Chain Fatty Acid Uptake In Orthotopic Models Of Triple-Negative Breast Cancer, Megan C. Madonna, Joy E. Duer, Joyce V. Lee, Jeremy Williams, Baris Avsaroglu, Caigang Zhu, Riley Deutsch, Roujia Wang, Brian T. Crouch, Matthew D. Hirschey, Andrei Goga, Nirmala Ramanujam

Biomedical Engineering Faculty Publications

Targeting a tumor’s metabolic dependencies is a clinically actionable therapeutic approach; however, identifying subtypes of tumors likely to respond remains difficult. The use of lipids as a nutrient source is of particular importance, especially in breast cancer. Imaging techniques offer the opportunity to quantify nutrient use in preclinical tumor models to guide development of new drugs that restrict uptake or utilization of these nutrients. We describe a fast and dynamic approach to image fatty acid uptake in vivo and demonstrate its relevance to study both tumor metabolic reprogramming directly, as well as the effectiveness of drugs targeting lipid metabolism. Specifically, …