Cellular and Molecular Physiology Commons^™

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 …

Chronic Inflammation: The Link Between A High Added Sugar Diet And Disease, Anna Collins

Senior Honors Theses

The modern diet includes many processed foods that contain added sugars, resulting in a significant increase in daily glucose and fructose consumption. Considering this, there is an increased effort to uncover the effects of excess sugar intake on the body’s health and metabolism. Strong evidence supports the connection between a high added sugar diet and the presence of chronic, low-grade inflammation due to cellular distress and metabolic dysfunction. Prolonged inflammatory responses are linked to tissue damage and the development of various metabolic diseases that are prevalent in modern society, such as obesity, fatty liver disease, cardiovascular disease, and type 2 …

Editorial: Frontiers In The Midlands Society Of Physiological Sciences (2023-2024), Sathish Kumar Natarajan, Hong Zheng, Surabhi Chandra, Harold D. Schultz, William C.W. Chen

Journal Articles: Cellular & Integrative Physiology

No abstract provided.

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 …

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 …

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 …

Decreased Activity Of Phosphofructokinase-1 In Flight Muscle Cells Of Hawk Moth Manduca Sexta With Age, Owen G. Alvine

Honors Thesis

The phosphofructokinase-1 (PFK-1) enzyme is important for the catalyzation and regulation of glycolysis, especially in muscle. Investigating age-related changes in PFK-1 activity will provide insights into the metabolism shifts in muscle cells of our muscle aging model. The hawk moth, Manduca sexta, was chosen as the model organism because of its unique endothermic, synchronous flight muscles that are more analogous to vertebrates than invertebrate species. We hypothesized that PFK-1 activity will increase in muscle cells of aged moths due to dysregulation of the mitochondria. This was predicted to change the method of energy production, by hindering oxidative phosphorylation, making glycolysis …

Cold-Induced Metabolic Changes In Lean, Nag-1 Transgenic Mice, Rachel J. Davey

All Master's Theses

Obesity is a multifaceted metabolic disorder with severe worldwide public health consequences. While obesity can often be treated using diet and exercise, there are complex genetic interactions driving obesity that don’t always respond to such changes. One important research focus for addressing genetic factors is activating brown adipose tissue which increases thermogenesis, the process of burning stored fats to generate heat. Cold exposure is a known way to activate brown adipose tissue through b3-adrenergic signaling. This signaling pathway causes an upregulation of thermogenesis in brown adipocytes and beige adipocytes, which is white adipose tissue that “browns” and becomes metabolically active. …

Human Retinal Organoids Release Extracellular Vesicles That Regulate Gene Expression In Target Human Retinal Progenitor Cells, Jing Zhou, Miguel Flores‑Bellver, Jianbo Pan, Alberto Benito‑Martin, Cui Shi, Onyekwere Onwumere, Jason Mighty, Jiang Qian, Xiufeng Zhong, Tasmim Hogue, Baffour Amponsah‑Antwi, Linda Einbond, Rajendra Gharbaran, Hao Wu, Bo‑Juen Chen, Zhiliang Zheng, Tatyana Tchaikovskaya, Xusheng Zhang, Hector Peinado, Maria Valeria Canto‑Soler, Stephen Redenti

Publications and Research

The mechanisms underlying retinal development have not been completely elucidated. Extracellular vesicles (EVs) are novel essential mediators of cell‑to‑cell communication with emerging roles in developmental processes. Nevertheless, the identification of EVs in human retinal tissue, characterization of their cargo, and analysis of their potential role in retina development has not been accomplished. Three‑dimensional retinal tissue derived from human induced pluripotent stem cells (hiPSC) provide an ideal developmental system to achieve this goal. Here we report that hiPSC‑derived retinal organoids release exosomes and microvesicles with small noncoding RNA cargo. EV miRNA cargo‑predicted targetome correlates with Gene Ontology (GO) pathways involved in …

Physiological And Behavioral Correlates Of Hif-1 Alpha Protein Levels In The Gulf Killifish, Fundulus Grandis, Jasmine Harris

LSU New Orleans Theses and Dissertations

Although the hypoxia-inducible transcription factor (HIF) orchestrates molecular responses to low oxygen, the amount of HIF-1α protein expressed during hypoxia varies among species, individuals, and tissues. This study measured HIF-1α protein levels along with several physiological and behavioral variables in the estuarine fish Fundulus grandis under normoxia (> 7 mg l^-1 dissolved oxygen) and hypoxia (1 mg l^-1 dissolved oxygen). Fish under hypoxic conditions had higher tissue levels of HIF-1α, hematocrit, blood glucose, blood lactate, frequency of aquatic surface respiration (ASR), and lower activity than normoxic controls. Under hypoxia, HIF-1α abundance in gill was positively correlated with body …

Glucose Metabolism Of Breast Cancer Sub-Clones That Preferentially Metastasize To The Lungs And Bone, Anna G. Skubiz

Honors Theses

Malignant breast cancers exhibit preferential metastasis to bone and lung (1). While changes in gene expression in lung-specific (LM) and bone-specific metastasis (BoM) lines derived from the MDA-MB-231 breast cancer line have been identified, few metabolic genes are differentially expressed; thus it is unknown if tissue-specific metabolic reprogramming occurs. Two hallmarks of cancer cells are an altered metabolic phenotype characterized by enhanced conversion of glucose to lactate in spite of adequate oxygen availability for complete mitochondrial oxidation of this substrate (referred to as aerobic glycolysis or the Warburg effect) and a greater dependence on glutamine. These changes in primary tumor …

Genetic And Cellular Models For The Study Of Ptk2b And Adam10 In Adaptive Thermogenesis And Metabolism, Jared S. Farrar

Theses and Dissertations

In a cellular model, we demonstrate that the non-receptor protein tyrosine kinase 2 beta (PTK2B) plays a critical role in mouse cultured beige adipocyte differentiation. CRISPR/Cas9-mediated knock-out of Ptk2b results in non-differentiating white adipocytes and differentiated beige adipocytes with significantly reduced thermogenic gene and protein expression, enlarged lipid droplet size, and altered mitochondrial respiration. Together, these data in a cell culture system provide evidence for a role of PTK2B in the differentiation of mouse beige adipocytes.

In the process of developing a new mouse model utilizing the adipocyte selective Adipoq-Cre transgenic mouse, strong genetic linkage between a gene …

Pyruvate Kinase Isoform M2 Influences Autophagy And Related Processes In Hepatocellular Carcinoma Cells, Matthew Lin

University Scholar Projects

Hepatocellular carcinoma (HCC) is the most common form of liver cancer that affects ~14 million people in the world. Like all cancers, HCC is a disease that arises from unstinted cellular growth initiated by genetic alterations, metabolic changes, and dysregulation in key cellular pathways. Of interest is the relationship between metabolism and cell proliferation/degradation for therapeutic targeting. Pyruvate kinase M2 is a dimeric, glycolytically inactive isoform of the final enzyme involved in glycolysis, that is often upregulated in cancerous tissue. It is thought that the enzymatic function of PKM2 outside of glycolysis contributes to the biosynthesis of anabolic intermediates used …

Serine-Dependent Sphingolipid Synthesis Is A Metabolic Liability Of Aneuploid Cells, Sunyoung Hwang, H. Tobias Gustafsson, Ciara O’Sullivan, Gianna Bisceglia, Xinhe Huang, Christian Klose, Andrej Schevchenko, Robert C. Dickson, Paola Cavaliere, Noah Dephoure, Eduardo M. Torres

Molecular and Cellular Biochemistry Faculty Publications

Aneuploidy disrupts cellular homeostasis. However, the molecular mechanisms underlying the physiological responses and adaptation to aneuploidy are not well understood. Deciphering these mechanisms is important because aneuploidy is associated with diseases, including intellectual disability and cancer. Although tumors and mammalian aneuploid cells, including several cancer cell lines, show altered levels of sphingolipids, the role of sphingolipids in aneuploidy remains unknown. Here, we show that ceramides and long-chain bases, sphingolipid molecules that slow proliferation and promote survival, are increased by aneuploidy. Sphingolipid levels are tightly linked to serine synthesis, and inhibiting either serine or sphingolipid synthesis can specifically impair the fitness …

On The Origin Of Superoxide Dismutase: An Evolutionary Perspective Of Superoxide-Mediated Redox Signaling., Adam J. Case

Journal Articles: Cellular & Integrative Physiology

The field of free radical biology originated with the discovery of superoxide dismutase (SOD) in 1969. Over the last 5 decades, a plethora of research has been performed in species ranging from bacteria to mammals that has elucidated the molecular reaction, subcellular location, and specific isoforms of SOD. However, while humans have only begun to study this class of enzymes over the past 50 years, it has been estimated that these enzymes have existed for billions of years, and may be some of the original enzymes found in primitive life. As life evolved over this expanse of time, these enzymes …

Effect Of Oxygen-Limiting Tidal Conditions On Muscle Metabolism And Structure In The Giant Acorn Barnacle, Balanus Nubilus, Katie O. Grady

Master's Theses

Crustacean muscle fibers are some of the largest cells in the animal kingdom, with fiber diameters in the giant acorn barnacle (Balanus nubilus) exceeding 3 mm. Sessile animals with extreme muscle sizes and that live in the hypoxia-inducing intertidal zone – like B. nubilus – represent ideal models for probing the effects of oxygen limitation on muscle cells. We investigated changes in metabolism and structure of B. nubilus muscle in response to: normoxic immersion, anoxic immersion, or air emersion, for acute (6h) or chronic (6h exposures twice daily for 2wks) time periods. Following exposure, we immediately measured hemolymph …

The Effect Of Transformed Escherichia Coli On The Mouse Intestine Microbiome: The Microbial Metabolic Enhancement Hypothesis, Bryar P. Kader

Senior Honors Theses

Metabolic disorders affect around thirty-four percent of the population in the United States. Among these disorders is lactose intolerance, which results from diminished production of the human lactase enzyme. This disorder and others like it are genetically determined and cannot be cured. However, the use of transformed bacteria implanted in the colon may provide a means by which the faulty pathway can be bypassed. To test whether transformed bacteria have the capability to aid in the digestion of normally indigestible compounds, a transformed strain of Escherichia coli overexpressing the beta-galactosidase enzyme encoded by the lacZ gene was colonized in the …

Dirigent Domain-Containing Protein Is Part Of The Machinery Required For Formation Of The Lignin-Based Casparian Strip In The Root, Prashant S. Hosmani, Takehiro Kamiya, John Danku, Sadaf Naseer, Niko Geldner, Mary Lou Guerinot, David Salt

Dartmouth Scholarship

The endodermis acts as a "second skin" in plant roots by providing the cellular control necessary for the selective entry of water and solutes into the vascular system. To enable such control, Casparian strips span the cell wall of adjacent endodermal cells to form a tight junction that blocks extracellular diffusion across the endodermis. This junction is composed of lignin that is polymerized by oxidative coupling of monolignols through the action of a NADPH oxidase and peroxidases. Casparian strip domain proteins (CASPs) correctly position this biosynthetic machinery by forming a protein scaffold in the plasma membrane at the site where …

Regulation Of Protein Degradation In The Heart By Amp-Activated Protein Kinase, Kedryn K. Baskin, Kedryn K. Baskin

Dissertations and Theses (Open Access)

The degradation of proteins by the ubiquitin proteasome system is essential for cellular homeostasis in the heart. An important regulator of metabolic homeostasis is AMP-activated protein kinase (AMPK). During nutrient deprivation, AMPK is activated and intracellular proteolysis is enhanced through the ubiquitin proteasome system (UPS). Whether AMPK plays a role in protein degradation through the UPS in the heart is not known. Here I present data in support of the hypothesis that AMPK transcriptionally regulates key players in the UPS, which, under extreme conditions can be detrimental to the heart. The ubiquitin ligases MAFbx /Atrogin-1 and MuRF1, key regulators of …