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The Effects of Dietary Selenium Intake and Lipopolysaccharide

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The Effects of Dietary Selenium Intake and Lipopolysaccharide THE EFFECTS OF DIETARY SELENIUM INTAKE AND LIPOPOLYSACCHARIDE STIMULATION ON SELECTED IMMUNE AND INFLAMMATORY MARKERS IN C57BL/6 MICE By HANA NEKATEBEB BEKELE Bachelor of Science in Medicine Addis Ababa University Addis Ababa, Ethiopia 1983 Master of Science in Community Health University of Heidelberg Heidelberg, Germany 1995 Submitted to the Faculty of the Graduate College of the Oklahoma State University in partial fulfillment of the requirements for the Degree of DOCTOR OF PHILOSOPHY May, 2012 THE EFFECTS OF DIETARY SELENIUM INTAKE AND LIPOPOLYSACCHARIDE STIMULATION ON SELECTED IMMUNE AND INFLAMMATORY MARKERS IN C57BL/6 MICE Dissertation Approved: Dr. Barbara J. Stoecker Dissertation Adviser Dr. Brenda J. Smith Dr. Edralin A. Lucas Dr. Katye M. Perry Outside Committee Member Dr. Sheryl A. Tucker Dean of the Graduate College i TABLE OF CONTENTS Chapter Page I. INTRODUCTION ......................................................................................................1 Overall Objective .....................................................................................................8 Specific Objectives ..................................................................................................8 Hypothesis................................................................................................................8 Significance of the Problem .....................................................................................9 Significance of the Study .........................................................................................9 Organization of the Dissertation ............................................................................10 II. REVIEW OF LITERATURE..................................................................................11 Metabolism of Selenium ........................................................................................12 Physiological Functions of Selenium.....................................................................18 Effect of Selenium on Immune Response ............................................................25 Requirements for Selenium....................................................................................30 Dietary Sources of Selenium .................................................................................32 Selenium Toxicity ..................................................................................................33 Health Consequences of Selenium Deficiency ......................................................34 Interaction of Selenium with Other Nutrients ........................................................36 Methods of Assessment .........................................................................................36 III. METHODOLOGY ................................................................................................42 Experimental Design and Animals ........................................................................42 Necropsy ................................................................................................................44 Laboratory Analysis ...............................................................................................45 ii Chapter Page IV. The Effect of Dietary Selenium Intake and Low Grade Inflammation on Selected Immune Cell Populations in C57BL/6 Mice .........................................................50 Abstract ..................................................................................................................50 Introduction ............................................................................................................51 Methods..................................................................................................................55 Results ....................................................................................................................58 Discussion ..............................................................................................................59 V. The Effect of Dietary Selenium and Low Grade Inflammation on Plasma Glutathione Peroxidase, Selenium and Antioxidant Capacity in C57BL/6 Mice 69 Abstract ..................................................................................................................69 Introduction ............................................................................................................70 Methods..................................................................................................................73 Results ....................................................................................................................75 Discussion ..............................................................................................................76 VI. Summary and Conclusion ......................................................................................83 Summary ................................................................................................................83 Conclusion .............................................................................................................85 Research Needs ......................................................................................................86 REFERENCES ............................................................................................................87 APPENDICES ...........................................................................................................109 iii LIST OF TABLES Table Page 2.1: Selenium Intake for Healthy US and Canadian Populations .............................31 2.2: Recommended Nutrient Intake of Selenium ......................................................32 4.1: Composition of Diets by Selenium Concentration (g/kg diet) ..........................62 4.2: Body and Thymus Weight of Mice Fed Supplemental Selenium with and without LPS .......................................................................................................63 4.3: Plasma Selenium of Mice Fed Supplemental Selenium with and without without LPS .....................................................................................................64 4.4: Total White Blood Cells and Differential Counts of Mice Fed Supplemental Selenium with or without LPS ...........................................................................65 4.5: Number of Th-cells, T-cells and B-cells in Bone Marrow of Mice Fed Supplemental Selenium with and without LPS ................................................66 4.6: Number of Bone Marrow Early blasst, Lymphocytes, Granulocytes and Monocytes in Mice Fed Supplemental Se with and without LPS ....................67 4.7: Plasma levels of Pro-Inflammatory Cytokines and IgG2a in Mice Fed Dietary Selenium with and without LPS ...........................................................68 5.1: Composition of Diets by Selenium Concentration (g/kg diet) ..........................78 5.2: Plasma GSH-Px Activity in Mice Fed Graded Supplemental Selenium with and without LPS .......................................................................................................79 iv 5.3: Plasma Se Concentration in Mice Fed Supplemental Selenium with and without LPS ........................................................................................................................80 5.4: Total Antioxidant Capacity in Mice Fed Supplemental Selenium with and with out LPS...................................................................................................................81 5.5: Plasma Albumin, Alkaline Phosphatase and Alanine Transaminase Level in Mice Fed Supplemental Selenium with and without LPS ...............................82 v LIST OF APPENDICES Appendix Page A. Oklahoma State University Institutional Animal Care and Use Approval Form ...............................................................................................................109 vi LIST OF FIGURES Figure Page 1.1: Overview of the Immune System ........................................................................3 2.1: Differences in Metabolic Pathways for Selenite and Selenate ..........................14 2.2: Metabolic Pathways for Selenium .....................................................................15 2.3: The Effects of Selenium on the Production of Ecosanoids ...............................26 3.1: Flowchart of Randomization .............................................................................43 vii ABREVATIONS AAS Atomic absorption spectrophotometry ALB Albumin ALP Alkaline phosphatase ALT Aminotransaminase CRP C - reactive protein Cys Cysteine DCs Dendritic cells DI-1 Deiodinase-1 DI-2 Deiodinase-2 DI-3 Deiodinase-3 FACS Fluorescence activated cell sorter FNB Food and Nutrition Board GSH Glutathione GSH-Px Glutathione peroxidase HDL High density lipoprotein H2O2 Hydrogen peroxide ICP-MS Inductively coupled plasma mass spectrophotometry IFNγ Interferon gamma Ig Immunoglobulin IKβα Inhibitory kappa beta alpha IL-12 Interleukin-12 viii INAA Instrumental neutron activation analysis LDL Low density lipoprotein LPS Lipopolysaccharide MAPK Mitogen activated protein kinase Met Methionine NBF Neutral buffered formalin NF-ĸβ Nuclear factor kappa beta NHANES National health and nutrition examination survey NKC Natural killer cells NOAEL No observed adverse effect level NO Nitric oxide ONOO Peroxynitrite PBS Phosphate buffered saline PLGSH-Px Phospholipid glutathione peroxidase RDA Recommended
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