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11-Cis Retinoids: Methods of Analysis and Handling, and Regeneration in Excised Bovine Eyes Gary Marshall Landers Iowa State University

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11-Cis Retinoids: Methods of Analysis and Handling, and Regeneration in Excised Bovine Eyes Gary Marshall Landers Iowa State University Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1987 11-Cis retinoids: methods of analysis and handling, and regeneration in excised bovine eyes Gary Marshall Landers Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Biochemistry Commons Recommended Citation Landers, Gary Marshall, "11-Cis retinoids: methods of analysis and handling, and regeneration in excised bovine eyes " (1987). Retrospective Theses and Dissertations. 8671. https://lib.dr.iastate.edu/rtd/8671 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. INFORMATION TO USERS The most advanced technology has been used to photo­ graph and reproduce this manuscript from the microfilm master. UMI films the original text directly from the copy submitted. Thus, some dissertation copies are in typewriter face, while others may be from a computer printer. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyrighted material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are re­ produced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Each oversize page is available as one exposure on a standard 35 mm slide or as a 17" x 23" black and white photographic print for an additional charge. Photographs included in the original manuscript have been reproduced xerographically in this copy. 35 mm slides or 6" X 9" black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. IHUMIAccessing the World's Information since 1938 300 North Zeeb Road, Ann Arbor, Ml 48106-1346 USA Order Number 8805101 11-Cis retinoids—methods of analysis and handling, and regeneration in excised bovine eyes Landers, Gary Marshall, Ph.D. Iowa State University, 1987 UMI SOON.ZeebRd Ann Arbor, MI 48106 PLEASE NOTE: In all cases this material has been filmed in the best possible way from the available copy. Problems encountered with this document have been identified here with a check mark V . 1. Glossy photographs or pages 2. 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Other 11-Cfs retinoids - methods of analysis and handling, and regeneration in excised bovine eyes by Gary Marshall Landers A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY Department: Biochemistry and Biophysics Major: Biochemistry Signature was redacted for privacy. In CMarge of Major Work Signature was redacted for privacy. For the Major D^^rtment Signature was redacted for privacy. For the Graduate College Iowa State University Ames, Iowa 1987 i i TABLE OF CONTENTS Page ABBREVIATIONS USED v GENERAL INTRODUCTION 1 Explanation of Dissertation Format 1 Literature Review 3 General vitamin A metabolism 3 Vitamin A in vision 5 The central events of vision 8 Regeneration of 11-CJ3 retinal and completion of the visual cycle 9 Problems in the analysis of retinoid isomers 17 SECTION I. STATISTICAL SOLVENT OPTIMIZATION FOR THE SEPARATION OF GEOMETRIC ISOMERS OF RETINOL BY HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY 20 ABSTRACT 22 INTRODUCTION 23 MATERIALS AND METHODS 26 RESULTS 30 DISCUSSION 37 ACKNOWLEDGEMENTS 39 REFERENCES 40 ii i SECTION II. ABSENCE OF ISOMERIZATION OF RETINYL PALMITATE, RETINOL, AND RETINAL IN CHLORINATED AND NONCHLORINATED SOLVENTS UNDER GOLD LIGHT 42 ABSTRACT 44 INTRODUCTION 45 MATERIALS AND METHODS 47 Solvents 47 Illumination 47 HPLC Methods 48 Purification and Identification of Retinyl Palmitate Isomers 49 NMR of Retinyl Palmitate Isomers 50 General Procedure 50 Testing of the Effects of Déuteration, Acidity, and Free-Radical Scavengers 51 RESULTS AND DISCUSSION 53 CONCLUSIONS 71 ACKNOWLEDGEMENTS 74 REFERENCES 75 SECTION III. RAPID, SIMULTANEOUS DETERMINATION OF ISOMERS OF RETINAL, RETINAL OXIME AND RETINOL BY HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY 76 ABSTRACT 78 INTRODUCTION 79 MATERIALS AND METHODS 81 Laboratory Lighting 81 HPLC Methods and Equipment 81 HPLC Solvents 82 Preparation of Retinoid Standards 82 i V Extraction of Retinas 84 RESULTS ' 86 DISCUSSION 97 ACKNOWLEDGEMENTS 101 REFERENCES 102 SECTION IV. ISOMERIZATION OF ALL-TRANS RETINOIDS TO THE 11-CIS CONFIGURATION IN OCULAR TISSUES 106 ABSTRACT 108 INTRODUCTION 109 MATERIALS AND METHODS 111 Laboratory Lighting 111 Solvents and Reagents 111 Collection and Incubation of Tissues 112 Homogenization and Extraction 113 HPLC Methods 115 Analysis of retinal oxime and retinol isomers 115 Analysis of retinyl ester isomers 115 Data Analysis 116 RESULTS 117 DISCUSSION 137 ACKNOWLEDGEMENTS 141 REFERENCES 142 OVERALL SUMMARY 145 ADDITIONAL REFERENCES 148 ACKNOWLEDGEMENTS 158 V ABBREVIATIONS USED E molar extinction coefficient (M~^cra"^) yg microgram(s) yl microliter(s) wM micromolar urn micrometer(s) BHT butylated hydroxytoluene C Centigrade cm centimeter(s) CRABP cellular retinoic-acid binding protein CRALBP cellular retinal-binding protein CRBP cellular retinol-binding protein ^i\in absorptivity of a 1% solution g gravity g gram(s) 1 liter(s) h hour(s) HPLC high-performance liquid chromatography M molar (moles/liter) MHz Megahertz min minute(s) ml milliliter mM miUimolar nm nanometer vi nirole nanomole O.D. optical density P probability pmole picomole r correlation coefficient RAL retinal RE retinyl ester(s) RO retinal oxime ROL retinol ROS rod outer segment RPE retinal pigment epithelium S.D. sample standard deviation t Student's t-statistic tj. chromatographic retention time UV ultraviolet VIS visible W watt(s) 1 GENERAL INTRODUCTION Explanation of Dissertation Format The body of this alternate format dissertation consists of four related manuscripts which have been published in refereed Journals, have been submitted to a refereed Journal, or will soon be submitted. Each of these manuscripts was written by Mr. Landers, with guidance and editorial input from Dr. Olson. They are preceded by a general introduction and literature review, and followed by a general summary. Sections I, II and III concern methodology for the analysis and handling of geometric isomers of retinoids, while Section IV details the application of the techniques and principles of the first three sections to the study of the visual cycle in bovine ocular tissues. Section I, "Statistical solvent optimization for the separation of geometric isomers of retinol by high-performance liquid chromatography" details a systematic study of the effects of various solvents on the resolution of isomers of retinol on normal-phase silica columns. Although the HPLC method developed in this study has since been abandoned in favor of a newer and more powerful technique (details of which are presented in Section III) many of the principles outlined and broad trends reported in this paper have been used to develop the present analytical methodology. This manuscript was published in the Journal of Chromatography, 291:51-57, 1984. 2 Section II, "Lack of isomerization of retinyl palmitate, retinol, and retinal in chlorinated and nonchlorinated solvents under gold light" was written in response to a published report of isomerization of retinyl palmitate in chlorinated solvents by light from gold fluorescent lamps. These lamps emit very little light of wavelengths less than 500 nm, and thus should not photoisomerize retinoids, which have absorption maxima in the 300-400 nm range. Because we use both chlorinated solvents and gold fluorescent lamps extensively in our laboratory, we felt compelled to carefully reinvestigate the effect ourselves. The result was a confirmation of the wisdom of using gold fluorescent lamps to prevent artifactual isomerization of retinoids, regardless of the solvent used. In addition, some interesting findings about solvent effects on the photoisomerization of various retinoids were made, and these facts have been utilized in preparing certain isomers of retinyl palmitate for use in subsequent studies. This manuscript was published in the Journal of the Association of Official Analytical Chemists, 69:50-55, 1986. Section III, "Rapid, simultaneous determination of isomers of retinaldehyde, retinal oxime and retinol by high-performance liquid chromatography" reports a new chromatographic method for simultaneously analyzing all the physiologically important isomers of retinol and retinaldehyde in extracts of ocular
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