Cellular and Molecular Physiology Commons^™

Diabetic Cardiomyopathy: An Immunometabolic Perspective., Paras K. Mishra, Wei Ying, Shyam Sundar Nandi, Gautam K. Bandyopadhyay, Kaushik K. Patel, Sushil K. Mahata

Journal Articles: Cellular & Integrative Physiology

The heart possesses a remarkable inherent capability to adapt itself to a wide array of genetic and extrinsic factors to maintain contractile function. Failure to sustain its compensatory responses results in cardiac dysfunction, leading to cardiomyopathy. Diabetic cardiomyopathy (DCM) is characterized by left ventricular hypertrophy and reduced diastolic function, with or without concurrent systolic dysfunction in the absence of hypertension and coronary artery disease. Changes in substrate metabolism, oxidative stress, endoplasmic reticulum stress, formation of extracellular matrix proteins, and advanced glycation end products constitute the early stage in DCM. These early events are followed by steatosis (accumulation of lipid droplets) …

Antiproliferative Effects Of Hibernating American Bullfrog (Rana Catesbeiana) Blood Plasma On Thp-1 Cells, Sean Robbins

Annual Graduate Student Symposium

Hibernation is an incredible adaptation that allows an organism to go dormant during the winter, when food is scarce. Much is unknown physiologically about hibernation, and most current research comes from mammalian models. During hibernation, the cells of mammals are impeded from going through mitosis. 13-lined ground squirrels (Ictidomys tridecemlineatus) and woodchucks (Marmota monax) have a protein, alpha-2-macroglobulin, in their blood plasma, which has significant antiproliferative effects on spleen cells. The goal of my study was to determine if an exothermic organism, the American Bullfrog (Rana catesbeiana), also actively suppresses mitosis while hibernating and if so, determine if it is …

Patterns Of Morphological And Molecular Evolution In The Antillean Tree Bat, Ardops Nichollsi (Chiroptera: Phyllostomidae), Roxanne J. Larsen, Peter A. Larsen, Caleb D. Phillips, Hugh H. Genoways, Gary G. Kwiecinski, Scott C. Pedersen, Carleton J. Phillips, Robert J. Baker

University of Nebraska State Museum: Mammalogy Papers

Species endemic to oceanic islands offer unique insights into the mechanisms underlying evolution and have served as model systems for decades. Often these species show phenotypic variation that is correlated with the ecosystems in which they occur and such correlations may be a product of genetic drift, natural selection, and/or environmental factors. We explore the morphologic and genetic variation within Ardops nichollsi, a species of phyllostomid bat endemic to the Lesser Antillean islands. Ardops nichollsi is an ideal taxon to investigate the tempo of evolution in Chiroptera, as it: is a recently derived genus in the family Phyllostomidae; contains …

Bioaccumulation Of Metallic Trace Elements And Antioxidant Enzyme Activities In Apfelbeckia Insculpta (L. Koch, 1867) (Diplopoda: Callipodida) From The Cave Hadži-Prodanova Pećina (Serbia), Jelena Vranković, Slavica Borković-Mitić, Bojan Ilić, Milanka Radulović, Slaviša Milošević, Slobodan Makarov, Bojan Mitić

International Journal of Speleology

The concentration of 10 metallic trace elements or MTE (Cu, Fe, Zn, Mn, As, Hg, Pb, Cd, Ni, and Cr) was measured in specimens of the troglophilic millipede Apfelbeckia insculpta (L. Koch, 1867) and sediment of the cave Hadži-Prodanova Pećina in western Serbia. Some MTE, like Fe and Mn, displayed much higher concentrations compared to other elements, both in the sediment and in the body of A. insculpta. On the other hand, estimation of the bioaccumulation factor (BAF) in both males and females of A. insculpta showed values greater than 1 for xenobiotic elements compared to those that are essential. …

Editing Of Misaminoacylated Trna Controls The Sensitivity Of Amino Acid Stress Responses In Saccharomyces Cerevisiae, Kyle Mohler, Rebecca Mann, Tammy J. Bullwinkle, Kyle W. Hopkins, Lin Hwang, Noah M. Reynolds, Brandon Gassaway, Hans-Rudolph Aerni, Jesse Rinehart, Michael Polymenis, Kym F. Faull, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Amino acid starvation activates the protein kinase Gcn2p, leading to changes in gene expression and translation. Gcn2p is activated by deacylated tRNA, which accumulates when tRNA aminoacylation is limited by lack of substrates or inhibition of synthesis. Pairing of amino acids and deacylated tRNAs is catalyzed by aminoacyl-tRNA synthetases, which use quality control pathways to maintain substrate specificity. Phenylalanyl-tRNA synthetase (PheRS) maintains specificity via an editing pathway that targets non-cognate Tyr-tRNA^Phe. While the primary role of aaRS editing is to prevent misaminoacylation, we demonstrate editing of misaminoacylated tRNA is also required for detection of amino acid starvation by …

Quality Control By Isoleucyl-Trna Synthetase Of Bacillus Subtilis Is Required For Efficient Sporulation, Elizabeth Kermgard, Zhou Yang, Annika-Marisa Michel, Rachel Simari, Jacqueline Wong, Michael Ibba, Beth A. Lazazzera

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Isoleucyl-tRNA synthetase (IleRS) is an aminoacyl-tRNA synthetase whose essential function is to aminoacylate tRNA^Ile with isoleucine. Like some other aminoacyl-tRNA synthetases, IleRS can mischarge tRNA^Ile and correct this misacylation through a separate post-transfer editing function. To explore the biological significance of this editing function, we created a ileS(T233P) mutant of Bacillus subtilis that allows tRNA^Ile mischarging while retaining wild-type Ile-tRNA^Ile synthesis activity. As seen in other species defective for aminoacylation quality control, the growth rate of the ileS(T233P) strain was not significantly different from wild-type. When the ileS(T233P) strain was assessed for its ability to promote …

Ms-Read: Quantitative Measurement Of Amino Acid Incorporation, Kyle Mohler, Hans-Rudolph Aerni, Brandon Gassaway, Jiqiang Ling, Michael Ibba, Jesse Rinehart

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Ribosomal protein synthesis results in the genetically programmed incorporation of amino acids into a growing polypeptide chain. Faithful amino acid incorporation that accurately reflects the genetic code is critical to the structure and function of proteins as well as overall proteome integrity. Errors in protein synthesis are generally detrimental to cellular processes yet emerging evidence suggest that proteome diversity generated through mistranslation may be beneficial under certain conditions. Cumulative translational error rates have been determined at the organismal level, however codon specific error rates and the spectrum of misincorporation errors from system to system remain largely unexplored. In particular, until …

Modulating Beta-Cardiac Myosin Function At The Molecular And Tissue Levels, Wanjian Tang, Cheavar A. Blair, Shane D. Walton, András Málnási-Csizmadia, Kenneth S. Campbell, Christopher M. Yengo

Physiology Faculty Publications

Inherited cardiomyopathies are a common form of heart disease that are caused by mutations in sarcomeric proteins with beta cardiac myosin (MYH7) being one of the most frequently affected genes. Since the discovery of the first cardiomyopathy associated mutation in beta-cardiac myosin, a major goal has been to correlate the in vitro myosin motor properties with the contractile performance of cardiac muscle. There has been substantial progress in developing assays to measure the force and velocity properties of purified cardiac muscle myosin but it is still challenging to correlate results from molecular and tissue-level experiments. Mutations that cause …

The Scaffolding Protein Iqgap1 Promotes Hepatic Proliferation And Protects The Liver From Injury, Hanna Erickson, Sayeepriyadarshini Anakk

Hepatobiliary Cancers: Pathobiology and Translational Advances

No abstract provided.

Transient Alt Activation Protects Human Primary Cells From Chromosome Instability Induced By Low Chronic Oxidative Stress, Elisa Coluzzi, Rossella Buonsante, Stefano Leone, Anthony J. Asmar, Kelley L. Miller, Daniela Cimini, Antonella Sgura

Bioelectrics Publications

Cells are often subjected to the effect of reactive oxygen species (ROS) as a result of both intracellular metabolism and exposure to exogenous factors. ROS-dependent oxidative stress can induce 8-oxodG within the GGG triplet found in the G-rich human telomeric sequence (TTAGGG), making telomeres highly susceptible to ROS-induced oxidative damage. Telomeres are nucleoprotein complexes that protect the ends of linear chromosomes and their dysfunction is believed to affect a wide range of cellular and/or organismal processes. Acute oxidative stress was shown to affect telomere integrity, but how prolonged low level oxidative stress, which may be more physiologically relevant, affects telomeres …

Metabolic And Morphologic Shifts In Neuro2a Cells Cultured In Galactose Medium, Leah Welker

Masters Theses

It has been observed that highly-proliferating cells, such as cancer cells, rely mainly on glycolysis for ATP production, regardless of presence of oxygen. This effect, however, can be reversed by changing the main energy substrate in the medium from glucose to galactose. The oxidation of galactose in glycolysis yields less net ATP, presumably forcing the cell into OXPHOS. This has been established in many cell lines, including HeLA, HepG2, and skeletal muscle cells. As of yet, this has not been reproduced in neuronal cells. Using Neuro2a, a murine neuroblastoma cell line, this study exposes neuronal cells to galactose medium, and …

Differential Activity And Content Of High-Affinity Glutamate Transporters, Content Of Their Regulatory Proteins, And Capacity For Glutamine And Glutathione Synthesis In Tissues Of Finished Versus Growing Steers, Jing Huang

Theses and Dissertations--Animal and Food Sciences

Improvement of feeding regimens for production animals has been hindered by a lack of fundamental knowledge about how the capacity to regulate nutrient absorption across cell membranes affects the function of nutrient metabolizing enzymes. The objective is to determine if the activities and protein content of system X^-_AG glutamate transporter, its regulatory protein (GTRAP3-18 and ARL6IP1), glutamine synthetase (GS) and glutathione (GSH) content, changes in liver (Experiment 1), longissimus dorsi (LM) and subcutaneous adipose tissue (SF) (Experiment 2) as beef steers transitioned from predominantly-lean (growing) to -lipid (finished) tissue accretion phases. In liver (Experiment 1), system X^{- …}

Pioglitazone, Neet Family Proteins, And Galactose Modulation Of Liver Cell Bioenergetics, David F. Grimm

Undergraduate Honors Theses

MitoNEET was discovered through interactions with a labeled and photoactive derivative of pioglitazone (pio), a drug used to increase peripheral insulin sensitivity. Its unique coordination of a [2Fe-2S] cluster by three cysteine residues (Cys-72, Cys-74, and Cys-83) and one histidine (His-87) gives this cluster both stability and the ability to be donated to acceptor proteins. These qualities allow mitoNEET to participate in a diversity of biological functions. Functions of mitoNEET and the consequences of pioglitazone (pio) treatment in human hepatocellular carcinoma (HepG2) cells cultured in glucose or galactose-based medium were examined by respiration and proliferation studies. Pio treatment decreased complex …

Functional Studies Of Novel Mosquito Stage-Specific Genes In The Malaria Parasite, Plasmodium Berghei., Kaitlyn Kiernan

Master's Theses

The development and survival of the malaria parasite Plasmodium within its mosquito vector is not very well understood. When the parasite is taken up by an Anopheles mosquito, it is exposed to digestive enzymes, reactive oxygen species, increasing pH, decreasing temperature, and a diverse microbial flora. Our lab is studying the adaptive mechanisms underlying parasite survival in this hostile environment, one of which is movement out of the midgut. In order to escape the midgut, the parasite develops into an elongated, motile form called the ookinete. I am investigating two genes, thioredoxin-like protein 1 (trxl-1) and subpellicular microtubule protein 1 …

Assessment Of Bovine Vascular Serotonin Receptor Populations And Transport Of Ergot Alkaloids In The Small Intestine, Miriam A. Snider

Theses and Dissertations--Animal and Food Sciences

Prior work using a contractility bioassay determined that the serotonin (5-HT) receptor subtype 5-HT_2A is present in bovine lateral saphenous veins and plays a role in ergot alkaloid-induced vascular contraction in steers grazing endophyte-infected (Epichloë coenophiala) tall fescue (Lolium arundinaceum). A study was conducted to determine what 5-HT receptors are involved in vasoconstriction of bovine gut vasculature. The findings of this study indicate that 5-HT_2A is present and may play a role in ergot alkaloid induced vasoconstriction. A second study was conducted to determine if ergot alkaloids were transported in the small intestine. The …

Ionic Regulation Of Critical Cellular Processes In Non-Excitable Cells, Brandon M. Franklin

Theses and Dissertations--Biology

There are long-standing hypotheses that endogenous ion currents act to control cell dynamics in development, wound healing and regeneration. However, the mechanisms employed by cells to detect the electric field (EF) and translate it into a discernable message to drive specific cell behaviors, such as migration, proliferation and differentiation, are not well understood. A better understanding of how cells are able to sense EFs and react to them is vital to understanding physiological mechanisms are involved in regeneration. Ion channel signaling provides a reasonable suspect for mediating these effects based on their documented involvement in proliferation, migration and differentiation.

To …

The Mechanical Properties Of Non-Failing And Failing Human Myocardium, Cheavar A. Blair

Theses and Dissertations--Physiology

Heart failure is a clinical syndrome that manifests when there are structural and functional impairments to the heart that reduces the ability of the ventricles to fill or eject blood. The syndrome affects ~6 million Americans and is responsible for nearly 300,000 deaths annually. At the core of the syndrome are dysfunctional sarcomeres, the machinery that drives cardiac contraction and relaxation. By assessing the mechanical properties of human cardiac tissue, the information provided in this dissertation will provide data that demonstrates how sarcomeric dysfunction contributes to heart failure in the left and right ventricles. Additionally, these data will supply information …

Rad Gtpase: Identification Of Novel Regulatory Mechanisms And A New Function In Modulation Of Bone Density And Marrow Adiposity, Catherine Nicole Kaminski Withers

Theses and Dissertations--Molecular and Cellular Biochemistry

The small GTP-binding protein Rad (RRAD, Ras associated with diabetes) is the founding member of the RGK (Rad, Rem, Rem2, and Gem/Kir) family that regulates voltage-dependent calcium channel function. Given its expression in both excitable and non-excitable cell types, the control mechanisms for Rad regulation and the potential for novel functions for Rad beyond calcium channel modulation are open questions. Here we report a novel interaction between Rad and Enigma, a scaffolding protein that also binds to the E3 ubiquitin ligase Smad ubiquitin regulatory factor 1 (Smurf1). Overexpression of Smurf1, but not …

Hydrogen Sulfide Regulation Of Kir Channels, Junghoon Ha

Theses and Dissertations

Inwardly rectifying potassium (Kir) channels establish and regulate the resting membrane potential of excitable cells in the heart, brain and other peripheral tissues. Phosphatidylinositol- 4,5-bisphosphate (PIP2) is a key direct activator of ion channels, including Kir channels. Gasotransmitters, such as carbon monoxide (CO), have been reported to regulate the activity of Kir channels by altering channel-PIP2 interactions. We tested, in a model system, the effects and mechanism of action of another important gasotransmitter, hydrogen sulfide (H2S) thought to play a key role in cellular responses under ischemic conditions. Direct administration of sodium hydrogen sulfide (NaHS), as an exogenous H2S source, …

Profiling The Action Of Acetylcholine In The Drosophila Melanogaster Larval Model: Heart, Behavior, And The Development And Maintenance Of Sensorimotor Circuits, Cole A. Malloy

Theses and Dissertations--Biology

Understanding the role of various chemical messengers in altering behaviors and physiological processes is a common goal for scientists across multiple disciplines. The main focus of this dissertation is on characterizing the action of an important neurotransmitter, acetylcholine (ACh), modulating larval Drosophila melanogaster neural circuits and heart. In this dissertation, I provide important insights into the mechanisms by which ACh influences the formation and performance of select neural circuits, while also revealing significant details regarding its role in additional physiological functions, including cardiac pace making. In Chapter 1, I provide a general overview of ACh action in mammals and flies …