DIET-INDUCED DYSLIPIDEMIA DRIVES STORE-OPERATED Ca2+ ENTRY, Ca2+ DYSREGULATION, NON-ALCOHOLIC STEATOHEPATITIS, AND CORONARY ATHEROGENESIS IN METABOLIC SYNDROME

DIET-INDUCED DYSLIPIDEMIA DRIVES STOREOPERATED Ca2+ ENTRY, Ca2+ DYSREGULATION, NONALCOHOLIC STEATOHEPATITIS, AND CORONARY ATHEROGENESIS IN METABOLIC SYNDROME Zachary Paul Neeb Submitted to the faculty of the University Graduate School in partial fulfillment of the requirements for the degree Doctor of Philosophy in the Department of Cellular and Integrative Physiology, Indiana University February 2010 Accepted by the Faculty of Indiana University, in partial fulfillment of the requirements for the degree of Doctor of Philosophy Michael Sturek, PhD, Chair Jeffrey A Breall, PhD Doctoral Committee Robert V Considine, PhD December 16, 2009 Alexander Obukhov, MD Johnathan D Tune, PhD ii Dedication To the family that raised me, Mom, Dad, Mamaw, and Drew, to the family I married, Dave, Joyce, Grandma, Granny, and Lindsey, and to my family, Jessica and Paul, I loved you then, I love you now, and I will always love you There are no words to describe my gratitude iii Acknowledgements My advisor, Michael Sturek, PhD, for his wisdom, guidance, and support; my committee Johnathan D Tune, PhD, Alexander Obukhov, PhD, Robert V Considine, PhD, and Jeffrey A Breall, MD, PhD, for greatly improving and influencing my thesis; Jason M Edwards, MD, PhD, and Ian N Bratz, PhD, for changing my outlook on life and contributing to the science; Mouhamad Alloosh, MD, James Wenzel, Reverend, James Byrd, and Xin Long, PhD, for their immense contributions; and the Cellular and Integrative Physiology Department, for providing an excellent environment and opportunity iv ABSTRACT Zachary Paul Neeb DIET-INDUCED DYSLIPIDEMIA DRIVES STORE-OPERATED Ca2+ ENTRY, Ca2+ DYSREGULATION, NON-ALCOHOLIC STEATOHEPATITIS, AND CORONARY ATHEROGENESIS IN METABOLIC SYNDROME Risk of coronary artery disease (CAD), the leading cause of death, greatly increases in metabolic syndrome Metabolic syndrome (MetS; obesity, insulin resistance, glucose intolerance, dyslipidemia, and hypertension) is increasing in prevalence with sedentary lifestyles and poor nutrition Non-alcoholic steatohepatitis (NASH; i.e MetS liver) is progressive and decreases life expectancy, with CAD as the leading cause of death Pathogenic Ca2+ regulation transforms coronary artery smooth muscle from a healthy, quiescent state to a diseased, proliferative phenotype thus majorly contributing to the development of CAD In particular, store-operated Ca2+ entry (SOCE) in vascular smooth muscle is associated with atherosclerosis Genetic predisposition may render individuals more susceptible to Ca2+ dysregulation, CAD, NASH, and MetS However, the metabolic and cellular mechanisms underlying these disease states are poorly understood Accordingly, the goal of this dissertation was to investigate the role of dyslipidemia within MetS in the development of Ca2+ dysregulation, CAD, and NASH The overarching hypothesis was that dyslipidemia within MetS would be necessary for induction of NASH and increased SOCE that would primarily mediate development of CAD To test this hypothesis we utilized the Ossabaw miniature swine model of MetS Swine were fed one of five diets for different lengths of time to induce varying severity of MetS Lean swine were fed normal maintenance chow diet F/MetS swine were fed high v Fructose (20% kcal) diet that induced normolipidemic MetS TMetS were fed excess high Trans-fat/cholesterol atherogenic diet that induced mildly dyslipidemic MetS and CAD XMetS were TMetS swine with eXercise DMetS (TMetS + high fructose) were moderately dyslipidemic and developed MetS and extensive CAD sDMetS (Short-term DMetS) developed MetS with mild dyslipidemia, but no CAD MMetS (Mixed-sourcefat/cholesterol/fructose) were severely dyslipidemic, exhibited NASH, and developed severe CAD Dyslipidemia in MetS predicted NASH severity (all groups < DMetS