The Efficacy of Pantothenic Acid As a Modifier of Body Composition in a Porcine Model of Obesity Development
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Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1-1-2004 The efficacy of pantothenic acid as a modifier of body composition in a porcine model of obesity development Carey Ann Baldwin Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Recommended Citation Baldwin, Carey Ann, "The efficacy of pantothenic acid as a modifier of body composition in a porcine model of obesity development" (2004). Retrospective Theses and Dissertations. 20349. https://lib.dr.iastate.edu/rtd/20349 This Thesis 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]. The efficacy of pantothenic acid as a modifier of body composition in a porcine model of obesity development by Carey Ann Baldwin A thesis submitted to the graduate faculty in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Major: Animal Nutrition Program of Study Committee: Tim Stahly, Major Professor Paul Flakoll Chad Stahl Iowa State University Ames, Iowa 2004 Copyright© Carey Ann Baldwin, 2004. All rights reserved. 11 Graduate College Iowa State University This is to certify that the master's thesis of Carey Ann Baldwin has met the thesis requirements of Iowa State University Signatures have been redacted for privacy 111 TABLE OF CONTENTS ACKNOWLEDGEMENTS Vl ABSTRACT Vll CHAPTER 1. GENERAL INTRODUCTION 1 Introduction 1 Thesis Organization 2 Literature Cited 2 CHAPTER 2. LITERATURE REVIEW 5 Body Composition and Tissue Accretion 5 Adipose Tissue Accretion 5 Depot Differences in Adipose Tissue Accretion 6 Energy Expenditure and Substrate Oxidation 7 Maintenance Requirements 9 Feed Restriction 10 Muscle Metabolism 11 Endocrine Function of Adipose Tissue 11 Other Factors Affecting Tissue Accretion 12 Glucose-Fatty Acid Cycle 12 Direct Fat Deposition 13 Lipogenesis 14 Fatty Acyl Synthase 14 De Novo Lipogenesis 15 Acetyl-CoA Carboxylase 15 Lipolysis 16 Peroxisomal Fatty Acid Beta-Oxidation 16 Acyl-CoA Oxidase 17 Species Differences in Fat Metabolism 17 lV Obesity 18 Obesity Characteristics 18 Obesity Complication - Insulin Resistance 19 Animal Models of Obesity 20 Dietary Fat 22 Dietary Carbohydrate 23 Pantothenic Acid 24 Pantothenic Acid Sources 24 Pantothenic Acid Requirements 25 Pantothenic Acid Deficiency 26 Pantothenic Acid Toxicity 27 Methods of Predicting Pantothenic Acid Levels 27 Pantothenic Acid in the Body 27 The Metabolic Role of Pantothenic Acid 28 The Role of Pantothenic Acid in Body Composition 30 Body Composition Measures 31 Dual-Energy X-Ray Absorptiometry 32 Proximate Analysis (Chemical Composition) 32 Subcutaneous Backfat Measures 33 Real-Time Polymerase Chain Reaction 33 Summary/Objectives 36 Literature Cited 37 CHAPTER 3. DUAL-ENERGY X-RAY ABSORPTIOMETRY FOR DETERMINATION OF BODY COMPOSITION IN PORCINE MODEL OF OBESITY DEVELOPMENT Abstract 49 Introduction 49 Materials and Methods 50 Results and Discussion 54 v Literature Cited 59 CHAPTER 4. EFFICACY OF P ANTOTHENIC ACID AS A MODIFIER OF BODY COMPOSITION IN A PORCINE MODEL OF OBESITY DEVELOPMENT Abstract 64 Introduction 64 Materials and Methods 65 Results and Discussion 69 Literature Cited 73 CHAPTERS. GENERALSUMMARY 91 VI ACKNOWLEDGEMENTS I would first like to recognize my Major Professor, Dr. Tim Stahly, for the opportunities, guidance and support he has provided throughout my graduate education at Iowa State University. I would also like to thank my committee members, Dr. Chad Stahl and Dr. Paul Flakoll, for their input and contributions to this thesis. In addition, I would like to thank the farm crew (Dan Johnson, Robert Tripp, Harlan Moody and John Simonson) for their humor and assistance with numerous diet mixings. I thank Kyle Dunn, Arlie Penner, Dongyan Wang, Sherri Swanton, and Brody Laabs for help with data collection and analysis. I could not have moved those pigs without your help. I would also like to thank Leslie Lincoln, Monica Perez-Garcia, Martha Jeffrey, and Laura Hittmeier for helping me to analyze laboratory samples. We have learned a lot along the way. I thank the Iowa State University Meats Laboratory for pig processing, Reid Landes for assistance with statistical analysis, and Kathy Hanson for DEXA analysis. Your contributions made the work a lot easier. For their friendship, assistance, and knowledge in countless areas, I thank Rich Clayton and Dr. Trevor Lutz. I am also very appreciative to the other members of the Molecular and Animal Nutrition Group for their support and numerous contributions to my graduate education. I give credit to Dr. Rodney Johnson and fellow Illini in the Laboratory oflntegrative Biology for inspiring me to pursue a graduate education. It is, however, the constant love and support of my husband, parents, family and friends that has allowed me to succeed in the · pursuit of my dreams. Your patience, interest and encouragement have kept me going. vu ABSTRACT The accuracy and precision of body composition measurement by Dual-Energy X-ray Absorptiometry (DEXA) and the efficacy ofpantothenic acid (PA) as a modifier of body composition in a pig model of obesity development were determined. Heavy weight barrows at six months of age were adjusted to a high fat basal diet with a calorie mix representative of that typically consumed by adults in the US (34 % of calories from fat) that provided daily dietary caloric intakes equivalent to 1.8 times their estimated body maintenance (110 kcal ME/ BW kg ·75 I day) needs based on the weekly mean BW of each animal. The basal diet provided PA in an amount that met or exceeded the current estimated needs of pigs and humans. This diet was expected to cause an obese state over a period of 144 d. At slaughter, the weights and tissue contents (fat, lean and bone mineral) of two body depots (carcass and internal organs) were evaluated by gravimetric, DEXA, and chemical measures. Subcutaneous carcass fat and longissimus muscle area measurements were also performed. The precision and accuracy of the DEXA estimates of the weight and tissue content of the two body depots were evaluated in thirty-three pigs (133-265 kg). DEXA scanning accurately estimated the carcass depot weight (+2 %) relative to that determined by gravimetric weighing. DEXA underestimated the fat tissue contents of the two depots (-19 and -26 %) and overestimated the lean tissue contents (13 and 27 %) relative to those estimated from chemical analysis of the fat and protein contents of the depots. However, DEXA precisely detected changes in carcass and organ depot weights (R2= .99, .99, respectively) and less precisely predicted changes in the depot's chemically determined fat (R2 = .95, .73) and protein content (R2= .88, .84). Specifically, for each 1 kg change in carcass and organ depot weights, DEXA predicted the changes with a 95 % confidence (2 SE of estimate) within± .008 and .026 kg, respectively. For each 1 kg change in the carcass and organ depot's chemically determined fat content, DEXA predicted the change within± .092 and .338 kg, respectively. The efficacy of supplemental PA (0, 80, 800, 8000 ppm) as a modifier of body composition was determined on pigs (17/treatment) that were randomly allotted to dietary Vlll treatment by body weight and date on test (block). Pigs with an initial BW and fat content of 154 kg and 27 %, respectively, accrued 73 kg ofBW of which 48 % was body fat in the obesity development model. BW gains, BW gain/feed ratios, feed intake, and subcutaneous backfat depths were not altered by PA additions. Whole body fat tissue content responded quadratically to increasing PA additions. Body fat percentage was reduced by .9 percentage units by the 80 ppm added PA and increased by 1.6 and 1.1 percentage units by the 800 and 8000 ppm added PA. Hepatic acetyl-CoA carboxylase, acyl-CoA oxidase, and fatty acid synthetase mRNA expression did not differ between the 0 and 8000 ppm supplemented PA diets. Based on these data, DEXA precisely predicts weight and tissue content in different body depots, and PA is not an efficient modifier of body composition in a porcine model of obesity development induced by a high fat dietary regimen. 1 CHAPTER!. GENERAL INTRODUCTION Introduction Obesity is becoming a worldwide epidemic, affecting both children and adults. The WHO (2003) states that more than one billion adults are overweight with at least 300 million of them being obese. In the U.S., 30.6% of adults were reported as obese in 2000-2001, with 16.5% of children being overweight (CSREES, 2004). The increasing incidence of the disease seems to be due in great part to more sedentary lifestyles coupled with consumption of more energy and nutrient-dense diets. Although some people may be more genetically prone to obesity, environmental factors seem to assist in its development, for its occurrence tends to be greater in urban areas and in individuals previously experiencing sub-optimal levels of nutrition (WHO, 1997; Frisancho, 2003; Jang et al., 2003). Obesity poses a major risk for chronic diseases such as type 2 diabetes, cardiovascular disease, hypertension, stroke and certain forms of cancer (WHO, 2003). Worldwide attention has shifted towards research in obesity prevention and therapy as health care costs skyrocket. Pantothenic acid is involved as a cofactor in lipid, carbohydrate, and protein metabolism. It has been shown to provide protective effects against radioactive and oxidative damage (Slyshenkov et al., 2004), to have a therapeutic role in wound healing (Weimann and Hermann, 1999), to stimulate blastocyst development and be beneficial to fetus survivability (McKieman and Bavister, 2000). Pantothenic acid and its derivatives have gained recently gained attention for their roles in lipid metabolism.