An Applied Physicist and proteomics expert at the University of Colorado Denver, Dr. Karen Jonscher's overarching goal is to apply her unique skill set, and an innate ability to synergize information from varied fields, toward creative hypothesis development and the independent pursuit of an innovative and productive applied biomedical research career. Her long-term objective is to apply quantitative analytical and bioinformatic approaches to understand the role of mitochondrial dysfunction and oxidative stress in obesity- related disease. Her short-term focus, and the subject of the proposed research, is to investigate molecular mechanisms whereby exposure to maternal over-nutrition programs future changes in kidney mitochondrial dysfunction, resulting in early-onset nephropathy. This K25 award will provide Dr. Jonscher with the support necessary to accomplish the following goals: 1) attain the educational background required to firmly anchor her ideas in the underlying biology and nutritional biochemistry of the systems she is investigating, 2) obtain exposure to molecular and cellular biology approaches that are important for the proposed work and her future independent research, 3) learn to implement cutting-edge metabolomic techniques in her research, 4) become expert at state-of-the-art advanced microscopy techniques used to investigate protein signaling and lipid metabolism, 5) build new skills for mentoring success and academic leadership and 6) develop a research program that will allow her to successfully compete as an independent biomedical investigator. To achieve these goals, Dr. Jonscher has capitalized on the outstanding educational resources available at the University of Colorado Denver Downtown and Anschutz Medical Campuses, as well as those provided by the Colorado Clinical and Translational Science Institute (NIH UL1 TR000154), the Nutrition and Obesity Research Center (P30 DK048520), the Division of Endocrinology, Diabetes and Metabolism, the Advanced Light Microscopy Core Facility and the Metabolic Core Lab in the design of her career development and training plan. Importantly, she has assembled a world-renowned mentoring team comprised of primary mentor Dr. Jed Friedman, whose lab investigates metabolic and genetic causes and consequences of maternal obesity and gestational diabetes mellitus (GDM) on the early developmental origins of obesity;co- mentor Dr. Moshe Levi, an expert in renal pathophysiology and advanced microscopy, studying regulation of phosphate and lipid metabolism in the pathogenesis of obesity, diabetes mellitus and age-related renal and vascular disease;advisor Dr. Jane Reusch, a clinical endocrinologist focused on understanding how diabetes, hyperglycemia and oxidative stress modulate activity of the cAMP Response Element Binding Protein in vascular disease;advisor Dr. Robert Rucker, an expert nutritional biochemist interested in elucidating the mechanism of action of pyrroloquinoline quinone (PQQ) in cells and mitochondria;advisor Dr. Manisha Patel, whose expertise lies in the study of oxidative stress and mitochondrial dysfunction in neurological disease, and advisor Dr. Sean Colgan, an expert epithelial cell biologist focused on the mechanistic role of hypoxia in disease. Each team member will assist with specific aspects of the research plan, offering help with protocols and method development, troubleshooting, and data interpretation. These senior-level academicians will help guide Dr. Jonscher's career path, provide advice on leading a laboratory and successfully mentoring students, and enable her to establish new collaborations and networks within the broader scientific community that will facilitate her transition to independence. The emergence of adult metabolic disease epidemics in young children is an enormous public health concern and is the focus of Dr. Jonscher's research goals. Global factors that may play a key role in this etiology include maternal diet and metabolism;mitochondrial dysfunction and oxidative stress are potentially important molecular drivers. However, early cellular origins and tissue-specific dysfunction related to maternal over-nutrition, particularly in the kidney, remain to be identified and disease biomarkers are not well established. Dr. Jonscher's compelling and novel preliminary data show altered lipid accumulation, collagen deposition and protein hyperacetylation in kidneys from juvenile offspring exposed to maternal obesity, suggesting a role for acetylation in regulating the metabolic response to high lipid loads. She proposes to characterize quantitative histological, biochemical and cellular markers of early-onset kidney disease (Aim 1) and correlate them with functionally important proteomic and metabolomic changes (Aim 2) using a high-fat diet mouse model of developmental programming. Endpoints of Aims 1 and 2 will be reassessed following intervention using the anti-oxidant pyrroloquinoline quinone (PQQ) to rescue the phenotype (Aim 3). These will be the first studies to 1) quantify alterations in renal lipid metabolism inducd by maternal obesity, 2) determine functional consequences of protein hyperacetylation in kidney metabolism following maternal lipid exposure, 3) identify a potential role for SIRT3 in regulating mitochondrial response to maternal over-nutrition, and 4) administer a potent anti-oxidant during pregnancy and lactation to rescue developmentally programmed "lipotoxicity." Results from these studies will provide novel protein and metabolite targets for Dr. Jonscher's future independent investigations and fresh insights into mechanisms by which metabolic disease may be propagated.
Alarmingly, 60 million children are expected to be overweight or obese by 2020 and incidence of childhood cardiovascular disease and diabetes is also on the rise. Maternal obesity has been related to this disturbing trend, however the underlying molecular mechanisms are not well understood. Our studies will investigate how kidney function is compromised in offspring of obese mothers and whether it can be restored by anti-oxidant treatment during pregnancy and lactation. Results from our studies may lead to new interventions to slow the progression of the diabesity epidemic.