Biochemical Phenomena, Metabolism, and Nutrition Commons^™

Yeast Copper Proteins And Reactive Oxygen Species In Effecting Lifespan, Megan Bestwick

Post-Grant Reports

Mitochondria are essential organelles in most eukaryotic cells because of their role in metabolism and the production of ATP by the oxidative phosphorylation (OXPHOS) pathway, as well as other key cellular processes. Metal cofactors, such as copper (Cu) and iron (Fe), are incorporated into OXPHOS protein complexes of yeast located within the inner membrane of the mitochondria. Misincorporation or modulation of these available metals in mitochondrial enzymes leads to the production of reactive oxygen species (ROS). ROS are reactive molecules containing oxygen such as peroxides, superoxide, and hydroxyl radicals. Yeast are a good model for studying aging and the effect …

Characterizing Aft1/2-Grx3/4 Interaction And The Role Of Bol2 During Iron Regulation In Saccharomyces Cerevisiae, William Rivers

Senior Theses

Iron dysregulation has been linked to a variety of human diseases, such as anemia, Friedreich’s ataxia, X-linked sideroblastic anemia, sideroblastic-like microcytic anemia, and myopathy. Thus, it is vitally important to understand the mechanisms for regulating intracellular iron. Here, we use fluorescence microscopy techniques in live cells to study interactions of the yeast proteins Grx3/4, Aft1/2, and Bol2, which have been shown to be involved in turning off iron import when the cell has adequate iron. Modified versions of genes encoding these proteins have been incorporated into several yeast backgrounds to use fluorescence to monitor interactions under varying iron levels.

Supervised Dimension Reduction For Large-Scale "Omics" Data With Censored Survival Outcomes Under Possible Non-Proportional Hazards, Lauren Spirko-Burns, Karthik Devarajan

COBRA Preprint Series

The past two decades have witnessed significant advances in high-throughput ``omics" technologies such as genomics, proteomics, metabolomics, transcriptomics and radiomics. These technologies have enabled simultaneous measurement of the expression levels of tens of thousands of features from individual patient samples and have generated enormous amounts of data that require analysis and interpretation. One specific area of interest has been in studying the relationship between these features and patient outcomes, such as overall and recurrence-free survival, with the goal of developing a predictive ``omics" profile. Large-scale studies often suffer from the presence of a large fraction of censored observations and potential …

Student-Faculty Collaborative Research Grant Report, Megan Bestwick

Post-Grant Reports

Mitochondria are essential organelles in most eukaryotic cells because of their role in metabolism and the production of ATP by the oxidative phosphorylation (OXPHOS) pathway, as well as other key cellular processes. Metal cofactors, such as copper (Cu) and iron (Fe), are incorporated into OXPHOS protein complexes of yeast located within the inner membrane of the mitochondria. Misincorporation or modulation of these available metals in mitochondrial enzymes leads to the production of reactive oxygen species (ROS). ROS are reactive molecules containing oxygen such as peroxides, superoxide, and hydroxyl radicals. Yeast are a good model for studying aging and the effect …

Toward An Enzyme-Coupled, Bioorthogonal Platform For Methyltransferases: Probing The Specificity Of Methionine Adenosyltransferases, Tyler D. Huber

Theses and Dissertations--Pharmacy

Methyl group transfer from S-adenosyl-l-methionine (AdoMet) to various substrates including DNA, proteins, and natural products (NPs), is accomplished by methyltransferases (MTs). Analogs of AdoMet, bearing an alternative S-alkyl group can be exploited, in the context of an array of wild-type MT-catalyzed reactions, to differentially alkylate DNA, proteins, and NPs. This technology provides a means to elucidate MT targets by the MT-mediated installation of chemoselective handles from AdoMet analogs to biologically relevant molecules and affords researchers a fresh route to diversify NP scaffolds by permitting the differential alkylation of chemical sites vulnerable to NP MTs that are unreactive to …

Relationship Of Sociodemographic Factors With Serum Levels Of Vitamin D In A Healthy Population Of Pakistan, Khalida Iqbal, Najmul Islam, Naseema Mehboobali, Ali Asghar, Saleem Perwaiz Iqbal, Mohammad Perwaiz Iqbal

Department of Biological & Biomedical Sciences

High prevalence of vitamin D deficiency has been reported from Pakistan. Association of sociodemographic factors with vitamin D status has received little attention in this region. Therefore, we embarked on investigating the relationship of sociodemographic factors with vitamin D levels in a healthy Pakistani population. Venous blood from 226 healthy participants (age range 19-69 years) was collected and analyzed for serum concentrations of 25(OH) vitamin D [25(OH)D] and other related biomarkers. Demographic characteristics of the study participants were collected. Vitamin D deficiency (25(OH)D levels less than 20 ng/ml) was found to be 75% in this cohort. Gender, sunlight exposure and …

Mitochondrial Metabolism In Major Neurological Diseases, Zhengqiu Zhou, Grant L. Austin, Lyndsay E. A. Young, Lance A. Johnson, Ramon Sun

Molecular and Cellular Biochemistry Faculty Publications

Mitochondria are bilayer sub-cellular organelles that are an integral part of normal cellular physiology. They are responsible for producing the majority of a cell’s ATP, thus supplying energy for a variety of key cellular processes, especially in the brain. Although energy production is a key aspect of mitochondrial metabolism, its role extends far beyond energy production to cell signaling and epigenetic regulation–functions that contribute to cellular proliferation, differentiation, apoptosis, migration, and autophagy. Recent research on neurological disorders suggest a major metabolic component in disease pathophysiology, and mitochondria have been shown to be in the center of metabolic dysregulation and possibly …

Bayesian Analytical Approaches For Metabolomics : A Novel Method For Molecular Structure-Informed Metabolite Interaction Modeling, A Novel Diagnostic Model For Differentiating Myocardial Infarction Type, And Approaches For Compound Identification Given Mass Spectrometry Data., Patrick J. Trainor

Electronic Theses and Dissertations

Metabolomics, the study of small molecules in biological systems, has enjoyed great success in enabling researchers to examine disease-associated metabolic dysregulation and has been utilized for the discovery biomarkers of disease and phenotypic states. In spite of recent technological advances in the analytical platforms utilized in metabolomics and the proliferation of tools for the analysis of metabolomics data, significant challenges in metabolomics data analyses remain. In this dissertation, we present three of these challenges and Bayesian methodological solutions for each. In the first part we develop a new methodology to serve a basis for making higher order inferences in metabolomics, …

Deciphering The Role Of Human Arylamine N-Acetyltransferase 1 (Nat1) In Breast Cancer Cell Metabolism Using A Systems Biology Approach., Samantha Marie Carlisle

Electronic Theses and Dissertations

Background: Human arylamine N-acetyltransferase 1 (NAT1) is a phase II xenobiotic metabolizing enzyme found in almost all tissues. NAT1 can additionally hydrolyze acetyl-coenzyme A (acetyl-CoA) in the absence of an arylamine substrate. NAT1 expression varies inter-individually and is elevated in several cancers including estrogen receptor positive (ER+) breast cancers. Additionally, multiple studies have shown the knockdown of NAT1, by both small molecule inhibition and siRNA methods, in breast cancer cells leads to decreased invasive ability and proliferation and decreased anchorage-independent colony formation. However, the exact mechanism by which NAT1 expression affects cancer risk and progression remains unclear. Additionally, consequences …

Defining Electron Bifurcation In The Electron-Transferring Flavoprotein Family, Amaya M. Garcia Costas, Saroj Poudel, Anne-Frances Miller, Gerrit J. Schut, Rhesa N. Ledbetter, Kathryn R. Fixen, Lance C. Seefeldt, Michael W. W. Adams, Caroline S. Harwood, Eric S. Boyd, John W. Peters

Chemistry Faculty Publications

Electron bifurcation is the coupling of exergonic and endergonic redox reactions to simultaneously generate (or utilize) low- and high-potential electrons. It is the third recognized form of energy conservation in biology and was recently described for select electron-transferring flavoproteins (Etfs). Etfs are flavin-containing heterodimers best known for donating electrons derived from fatty acid and amino acid oxidation to an electron transfer respiratory chain via Etf-quinone oxidoreductase. Canonical examples contain a flavin adenine dinucleotide (FAD) that is involved in electron transfer, as well as a non-redox-active AMP. However, Etfs demonstrated to bifurcate electrons contain a second FAD in place of the …

Mitochondrial Reactive Oxygen Species In Lipotoxic Hearts Induces Post-Translational Modifications Of Akap121, Drp1 And Opa1 That Promote Mitochondrial Fission, Kensuke Tsushima, Heiko Bugger, Adam R. Wende, Jamie Soto, Gregory A. Jenson, Austin R. Tor, Rose Mcglauflin, Helena C. Kenny, Yuan Zhang, Rhonda Souvenir, Xiao X. Hu, Crystal L. Sloan, Renata O. Pereira, Vitor A. Lira, Kenneth W. Spitzer, Terry L. Sharp, Kooresh I. Shoghi, Genevieve C. Sparagna, Eva A. Rog-Zielinska, Peter Kohl, Oleh Khalimonchuk, Jean E. Schaffer, E. Dale Abel

Department of Biochemistry: Faculty Publications

Rationale: Cardiac lipotoxicity, characterized by increased uptake, oxidation and accumulation of lipid intermediates, contributes to cardiac dysfunction in obesity and diabetes. However, mechanisms linking lipid overload and mitochondrial dysfunction are incompletely understood.

Objective: To elucidate the mechanisms for mitochondrial adaptations to lipid overload in postnatal hearts in vivo.

Methods and Results: Using a transgenic mouse model of cardiac lipotoxicity overexpressing long-chain acyl-CoA synthetase 1 in cardiomyocytes, we show that modestly increased myocardial fatty acid uptake leads to mitochondrial structural remodeling with significant reduction in minimum diameter. This is associated with increased palmitoyl-carnitine oxidation and increased reactive oxygen species (ROS) generation …

Exploring Cancer Metabolism Using Stable Isotope-Resolved Metabolomics (Sirm), Ronald C. Bruntz, Andrew N. Lane, Richard M. Higashi, Teresa W. -M. Fan

Center for Environmental and Systems Biochemistry Faculty Publications

Metabolic reprogramming is a hallmark of cancer. The changes in metabolism are adaptive to permit proliferation, survival, and eventually metastasis in a harsh environment. Stable isotope-resolved metabolomics (SIRM) is an approach that uses advanced approaches of NMR and mass spectrometry to analyze the fate of individual atoms from stable isotope-enriched precursors to products to deduce metabolic pathways and networks. The approach can be applied to a wide range of biological systems, including human subjects. This review focuses on the applications of SIRM to cancer metabolism and its use in understanding drug actions.

Novel Interconnections In Lipid Metabolism Revealed By Overexpression Of Sphingomyelin Synthase-1, Gergana M. Deevska, Patrick P. Dotson Ii, Alexander A. Karakashian, Giorgis Isaac, Mark Wrona, Samuel B. Kelly, Alfred H. Merrill Jr., Mariana N. Nikolova‑Karakashian

Physiology Faculty Publications

This study investigates the consequences of elevating sphingomyelin synthase 1 (SMS1) activity, which generates the main mammalian sphingolipid, sphingomyelin. HepG2 cells stably transfected with SMS1 (HepG2-SMS1) exhibit elevated enzyme activity in vitro and increased sphingomyelin content (mainly C22:0- and C24:0-sphingomyelin) but lower hexosylceramide (Hex-Cer) levels. HepG2-SMS1 cells have fewer triacylglycerols than controls but similar diacylglycerol acyltransferase activity, triacylglycerol secretion, and mitochondrial function. Treatment with 1 mm palmitate increases de novo ceramide synthesis in both cell lines to a similar degree, causing accumulation of C16:0-ceramide (and some C18:0-, C20:0-, and C22:0-ceramides) as well as C16:0- and C18:0-Hex-Cers. In these experiments, the …

Loss Of Exogenous Androgen Dependence By Prostate Tumor Cells Is Associated With Elevated Glucuronidation Potential, Brenna M. Zimmer, Michelle E. Howell, Qin Wei, Linlin Ma, Trevor Romsdahl, Eileen G. Loughman, Jennifer E. Markham, Javier Seravalli, Joseph J. Barycki, Melanie A. Simpson

Department of Biochemistry: Faculty Publications

Prostate epithelial cells control the potency and availability of androgen hormones in part by inactivation and elimination. UDP-glucose dehydrogenase (UGDH) catalyzes the NAD⁺-dependent oxidation of UDP-glucose to UDP-glucuronate, an essential precursor for androgen inactivation by the prostate glucuronidation enzymes UGT2B15 and UGT2B17. UGDH expression is androgen stimulated, which increases the production of UDP-glucuronate, and fuels UGT-catalyzed glucuronidation. In this study, we compared the glucuronidation potential and its impact on androgen-mediated gene expression in an isogenic LNCaP model for androgen dependent versus castration resistant prostate cancer. Despite significantly lower androgen-glucuronide output, LNCaP 81 castration resistant tumor cells expressed higher …

Zn(Ii), Cu(Ii), Sn(Ii), And Ni(Ii) And Other Metal Cations Do Not Prevent The Aggregation Of Hiapp, Charles Hoying

Honors Thesis

The Zn(II) metal ion has been shown to interact with Islet Amyloid Polypeptide (IAPP), a protein implicated in the progression of Type II Diabetes Mellitus, in such a way as to prevent the protein from aggregating into toxic fibers. We set out to find whether other metal ions might similarly prevent IAPP aggregation. Using Thioflavin T (ThT) spectroscopic assays, which measure fluorescence of ThT upon binding to aggregated IAPP, we observed a decrease in aggregation when incubated with Zn(II), Cu(II), Ni(II), and Sn(II). Atomic Force Microscopy (AFM), which can visualize fibril formation, revealed that the metals were not inhibiting IAPP …

Mitochondrial Function Assessed By 31p Mrs And Bold Mri In Non-Obese Type 2 Diabetic Rats, Yuchi Liu, Xunbai Mei, Jielei Li, Nicola Lai, Xin Yu

Electrical & Computer Engineering Faculty Publications

The study aims to characterize age-associated changes in skeletal muscle bioenergetics by evaluating the response to ischemia-reperfusion in the skeletal muscle of the Goto-Kakizaki (GK) rats, a rat model of non-obese type 2 diabetes (T2D). ³¹P magnetic resonance spectroscopy (MRS) and blood oxygen level-dependent (BOLD) MRI was performed on the hindlimb of young (12 weeks) and adult (20 weeks) GK and Wistar (control) rats. ³¹P-MRS and BOLD-MRI data were acquired continuously during an ischemia and reperfusion protocol to quantify changes in phosphate metabolites and muscle oxygenation. The time constant of phosphocreatine recovery, an index of mitochondrial oxidative capacity, …

Characterization Of Ghrelin O-Acyltransferase Active Site, Leslie Patton

Renée Crown University Honors Thesis Projects - All

Ghrelin, first discovered in 1999, is a 28-amino acid peptide hormone involved in the regulation of appetite, insulin secretion and sensitivity, and many neurological effects such as learning, memory, and depression.^1-6 Ghrelin has been identified to have a unique posttranslational octanoylation carried out by the enzyme ghrelin O-acyltransferase (GOAT). This distinctive modification is a point of interest in studying GOAT whereby blocking the acylation of the ghrelin could potentially halt the activity of the peptide hormone and provide a means of treating obesity, diabetes, and other diseases affected by ghrelin levels. The duration of my project involved working …

Liver Perilipin 5 Expression Worsens Hepatosteatosis But Not Insulin Resistance In High Fat-Fed Mice, Michelle B. Trevino, David Mazur-Hart, Yui Machida, Timothy King, Joseph Nadler, Elena V. Galkina, Arjun Poddar, Sucharita Dutta, Yumi Imai

Mathematics & Statistics Faculty Publications

Perilipin 5 (PLIN5) is a lipid droplet (LD) protein highly expressed in oxidative tissues, including the fasted liver. However, its expression also increases in nonalcoholic fatty liver. To determine whether PLIN5 regulates metabolic phenotypes of hepatosteatosis under nutritional excess, liver targeted overexpression of PLIN5 was achieved using adenoviral vector (Ad-PLIN5) in male C57BL/6J mice fed high-fat diet. Mice treated with adenovirus expressing green fluorescent protein (GFP) (Ad-GFP) served as control. Ad-PLIN5 livers increased LD in the liver section, and liquid chromatography with tandem mass spectrometry revealed increases in lipid classes associated with LD, including triacylglycerol, cholesterol ester, and phospholipid classes, …

The Role Of Sirtuin 1 And Ceramide In T10C12 Conjugated Linoleic Acid Induced Delipidation In 3t3-L1 Adipocytes, Wei Wang

Department of Animal Science: Dissertations, Theses, and Student Research

Project 1: Trans-10, cis-12 conjugated linoleic acid (t10c12 CLA) reduces triglyceride (TG) levels in adipocytes through multiple pathways, with AMP-activated protein kinase (AMPK) generally facilitating, and peroxisome proliferator-activated receptor γ (PPARγ) generally opposing these reductions. Sirtuin 1 (SIRT1), a histone/protein deacetylase that affects energy homeostasis, often functions coordinately with AMPK, and is capable of binding to PPARγ, thereby inhibiting its activity. This study investigated the role of SIRT1 in the response of 3T3-L1 adipocytes to t10c12 CLA by testing the following hypotheses: 1) SIRT1 is functionally required for robust TG reduction; …

Metabolic Reprogramming Induced By Ketone Bodies Diminishes Pancreatic Cancer Cachexia, Surendra K. Shukla, Teklab Gebregiworgis, Vinee Purohit, Nina V. Chaika, Venugopal Gunda, Prakash Radhakrishnan, Kamiya Mehla, Iraklis I. Pipinos, Robert Powers, Fang Yu, Pankaj K. Singh

Robert Powers Publications

Background: Aberrant energy metabolism is a hallmark of cancer. To fulfill the increased energy requirements, tumor cells secrete cytokines/factors inducing muscle and fat degradation in cancer patients, a condition known as cancer cachexia. It accounts for nearly 20% of all cancer-related deaths. However, the mechanistic basis of cancer cachexia and therapies targeting cancer cachexia thus far remain elusive. A ketogenic diet, a high-fat and low-carbohydrate diet that elevates circulating levels of ketone bodies (i.e., acetoacetate, β-hydroxybutyrate, and acetone), serves as an alternative energy source. It has also been proposed that a ketogenic diet leads to systemic metabolic changes. Keeping in …

Biochemical Assay Optimization And Computational Screening Efforts To Identify Potential Luxs Inhibitors, Keeshia Q. Wang

Master's Theses

Quorum sensing (QS) is a process of coordination of bacterial gene expression in response to cell population. System two QS is regulated by the small signaling molecule autoinducer-2 (AI-2) and is implicated in the infectious behaviors of various bacterial species. AI-2 is biosynthesized from S-ribosylhomocysteine (SRH) by the enzyme LuxS and induces interspecies cell-to-cell communication. Inhibition of LuxS would therefore inhibit interspecies QS. Herein, a search for novel molecular species that will competitively bind with SRH in the LuxS binding site is performed in silico. Computational screening results are then validated in vitro using an optimized LuxS inhibition …

Investigating Therapeutic Options For Lafora Disease Using Structural Biology And Translational Methods, Amanda R. Sherwood

Theses and Dissertations--Molecular and Cellular Biochemistry

Lafora disease (LD) is a rare yet invariably fatal form of epilepsy characterized by progressive degeneration of the central nervous and motor systems and accumulation of insoluble glucans within cells. LD results from mutation of either the phosphatase laforin, an enzyme that dephosphorylates cellular glycogen, or the E3 ubiquitin ligase malin, the binding partner of laforin. Currently, there are no therapeutic options for LD, or reported methods by which the specific activity of glucan phosphatases such as laforin can be easily measured. To facilitate our translational studies, we developed an assay with which the glucan phosphatase activity of laforin as …

Regulation Of Protein Degradation In The Heart By Amp-Activated Protein Kinase, 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 …

Map Kinases Couple Hindbrain-Derived Catecholamine Signals To Hypothalamic Adrenocortical Control Mechanisms During Glycemia-Related Challenges, Arshad Khan, Kimberly Kaminski, Graciela Sanchez-Watts, Todd Ponzio, J. Kuzmiski, Jaideep Bains, Alan Watts

Selected Works Temporary Series

No abstract provided.

Map Kinases Couple Hindbrain-Derived Catecholamine Signals To Hypothalamic Adrenocortical Control Mechanisms During Glycemia-Related Challenges, Khan, Kimberly Kaminski, Graciela Sanchez-Watts, Todd Ponzio, J. Kuzmiski, Jaideep Bains, Alan Watts

Departmental Papers (Biology)

No abstract provided.

Nerve, Muscle, Blood, Toil, Tears, And Sweat: England’S Pioneering Biophysicist, Soldier, And Statesman, Arshad Khan

Selected Works Temporary Series

No abstract provided.

Nerve, Muscle, Blood, Toil, Tears, And Sweat: England’S Pioneering Biophysicist, Soldier, And Statesman, Khan

Departmental Papers (Biology)

No abstract provided.

Gender Bias Of Cardiovascular Risk In Caucasian Type Ii Diabetics: A Haemostatic Explanation?, William Quirke

Theses

People with type II diabetes are disproportionately affected by cardiovascular disease compared to those without diabetes. The relative risk of cardiovascular disease caused by type II diabetes is higher in females than in males. This risk has not been fully explained by traditional risk factors and attention has turned to the possible role of haemostatic abnormalities in explaining the excess cardiovascular morbidity and mortality among diabetic females. We examined specific parameters of the coagulation (factor VII, factor VIII, von Willebrand factor, fibrinogen) and fibrinolytic (plasminogen activator inhibitor- 1, thrombin-activatable fibrinolysis inhibitor) system in 113 Irish Caucasian type II diabetics to …

A Role For The Forebrain In Mediating Time-Of-Day Differences In Glucocorticoid Counterregulatory Responses To Hypoglycemia In Rats, Lori Gorton, Arshad Khan, Maryann Bohland, Graciela Sanchez-Watts, Casey Donovan, Alan Watts

Selected Works Temporary Series

No abstract provided.

A Role For The Forebrain In Mediating Time-Of-Day Differences In Glucocorticoid Counterregulatory Responses To Hypoglycemia In Rats, Gorton, Arshad Khan, Maryann Bohland, Graciela Sanchez-Watts, Casey Donovan, Alan Watts

Departmental Papers (Biology)

No abstract provided.