Biomedical Base
Harvard Clinical Nutrition Research Center
Biomedical Base
Obesity
Following are the primary investigators of this theme and a brief discussion of their work.
Alison Field
Dr. Field is a new Investigator in the HCNRC renewal. She bridges the Department of Nutrition/Epidemiology at the HSPH and the Adolescent Division at Children’s Hospital. Her research focuses on the modifiable causes, correlates, consequences, and course of overweight and disordered eating among children, adolescents, and adult women. At present, her research bases are the approximately 15,000 adolescents and young adults in the National Longitudinal Study of Adolescent Health, 116,000 adult women in the Nurses’ Health Study II and 16,800 of their children who comprise the Growing Up Today Study. As part of a career development award from NIH, she assessed the consequences and correlates of weight cycling among women in the Nurses’ Health Study II and I plan to study predictors of weight loss maintenance among these women. However, the majority of her research is focused on children and adolescents. She is a co-founder of the Growing Up Today Study, which was established in 1996 to assess the predictors of dietary intake, activity, and weight gain during a four year period. Her research within the study is primarily related to the epidemiology of weight gain, weight concerns, weight control practices, and bulimic behaviors. She is the principal investigator on the NIH grant to continue following the Growing Up Today Study cohort from 2002 to 2007 to investigate determinants of binge eating, purging (i.e., use of vomiting or laxatives) and eating disorders of at least subsyndromal severity. In addition, she is the principal investigator of a NIH grant to study the prospective relationship between weight control behaviors and weight change among the multiethnic adolescents and young adults in the National Longitudinal Study of Adolescent Health.
Biographical sketch forthcoming.
Elizabeth Goodman
Dr. Goodman joins the HCNRC renewal as a new Investigator and brings a new perspective to the obesity research group. She is a pediatrician with sub-specialty training in adolescent medicine and is a Professor of Child and Adolescent Health and Director of Child and Adolescent Health Research at the Heller School for Social Policy and Management, Brandeis University , and a Lecturer in Pediatrics at Harvard Medical School. Dr. Goodman is also Professor and Associate Chair of the Health, Science, Society, and Policy Program at Brandeis University, an NIH-supported interdisciplinary program for students interested in studying not only the biology of disease, but the complex interplay of the social, economic, and political determinants of health. She received her general pediatric and sub-specialty training at Children’s Hospital, Boston; she was also a Robert Wood Johnson Clinical Scholar at UCSF and fellow at the Joint Program in Society and Health at New England Medical Center and the Harvard School of Public Health. Prior to her tenure at Brandeis, she was a member of the faculty at Harvard Medical School and the University of Cincinnati College of Medicine. Her research focuses on social stratification and its effect on adolescent health, particularly in relation to the development of obesity and other cardiovascular risks. She is a William T. Grant Scholar and Network Associate of the MacArthur Network on Socioeconomic Status and Health.
Gokhan Hotamisligil
Dr. Hotamisligil continues as an Investigator in the HCNRC renewal. During the last funding period, he was given an endowed chair and became Chairman of a newly established department, the Department of Genetics and Complex Diseases at the Harvard School of Public Health. He remains a Professor in the Department of Nutrition at the Harvard School of Public Health. The research program in Dr. Hotamisligil’s group revolves around three related areas, all of which deal with systemic metabolic equilibrium and the diseases that emerge from its abnormalities. 1) Adipocyte differentiation/development; 2) Stress, inflammation in type 2 diabetes; and 3) Molecular mechanisms of metabolic syndrome. Work in this area is currently focused on the identification of pathways regulated by these proteins to gain novel insights into how lipid-mediated biology is controlled at the cellular level. Also of interest is the possibility of identifying common components of nutrient and pathogen sensing pathways and characterizing novel signaling networks that are established between adipocytes, macrophages and other metabolically critical sites.
Lee Kaplan
Dr. Kaplan continues as an Investigator in the HCNRC. He also remains on the Executive Committee of the Center. For the last six years, he has headed the Weight Reduction Program at MGH and has established a new, comprehensive basic and clinical research program in obesity. His laboratory is pursuing a wide variety of basic and clinical studies related to body weight regulation, pathogenesis of obesity and its complications, and obesity treatments. 1) A major effort is focused on the mechanisms of weight loss after gastrointestinal weight loss surgery (GIWLS) and clinical outcomes from these procedures. Research programs related to GIWLS are grouped into three major areas: (1) mechanisms of action; (2) clinical outcomes; (3) patient-specific predictors of outcome. These are complemented by a newly established clinical trials program. 2) Mechanistic studies in animal models. The rat is a particularly valuable model for studying obesity, since it is highly amenable to behavioral and pharmacological manipulation, and there is a wealth of information about diverse physiological processes. They have recently developed new rat models of Roux-en-Y gastric bypass (RYGB) and adjustable gastric banding (AGB) that reproduce the clinical features of these operations in humans. Use of this model will permit dissection of the physiologic response to RYGB not possible in humans or even rats. In addition, technical success in establishing the mouse model has facilitated ongoing studies of the effects of RYGB in immature rats as a means of exploring the developmental contributions to obesity and weight regulation in this animal model. 3) Mechanistic studies in humans. In parallel studies, we are exploring the alterations in GI neuroendocrine signaling after RYGB. These changes include a modest decrease in hunger, a moderate increase in the frequency and eating-inhibitory effect of satiety, and, most significantly, a dramatic decrease in reward-based (non-hunger-related) eating. These studies complement the mechanistic studies in animal models described above.
Dr. Blackburn continues as an Investigator in the HCNRC renewal. As Associate Director of the Division of Nutrition and Director of the Center for the Study of Nutritional Medicine, he has been active in the HCNRC’s enrichment and clinical research activities. His research activities include: 1) an investigation of the insulin resistant response to weight loss surgery. There is a clear need for better understanding of the effects of GIWLS on contributors to food intake and the physiological and molecular mechanisms of these effects. It is also important to determine the degree to which GIWLS alters other components of the body’s weight regulatory system, including energy expenditure and nutrient handling (or partitioning. Limitation of the compensatory decrease in energy expenditure associated with weight loss may be an important component of the effectiveness of GIWLS. The magnitude of this effect, how many (and in which) patients it occurs, and its mechanisms are all important areas for study. 2) The metabolic effects of omentectomy. This proposal is for a prospective pilot study evaluating whether visceral fat reduction achieved through omentectomy can improve glucose tolerance and insulin sensitivity in obese individuals with type II diabetes. Laparoscopic omentectomy will be performed on viscerally obese patients with both body mass index (BMI) 30-40 kg/m2 and type II diabetes mellitus, with the hypothesis that omentectomy leads to significant improvement in glucose tolerance and insulin sensitivity. 3) A randomized trial of dietary fat reduction in postmenopausal women with primary breast cancer (WINS) Despite preclinical and observational studies suggesting benefit, dietary fat influence on breast cancer outcomes has been controversial. Dr. Blackburn’s group is conducting a randomized trial to test whether an intensive dietary intervention to reduce dietary fat intake was more effective than a control condition in postmenopausal women with primary resected breast cancer receiving conventional cancer management.
David Ludwig
Dr. Ludwig joins the HCNRC renewal as a new Investigator, having been an Associate Investigator during the previous research period. He completed a M.D./Ph.D. from Stanford before doing a pediatric residency and endocrine fellowship at Children’s Hospital of Boston. After doing research in Dr. Jeff Flier’s laboratory at the BIDMC, he was appointed Director of the Optimal Weight for Life (OWL) Program at Children’s Hospital. During the last several years he has shown in clinical studies that a diet with a high glycemic index is more likely to result in overweight during adolescent leading to obesity in adulthood. He has reported that a high carbohydrate diet is less likely to result in weight reduction than a higher fat diet at the same caloric level. He has trained several young investigators, including Dr. Cara Ebbeling, who received a P/F award last year. His work has also resulted in a prediction of a shorter life span for overweight adults due to multiple health complications (diabetes, hypertension, CVS and CVD disease).
Carine Lenders
Dr. Lenders joins the HCNRC renewal as a new Investigator, having been an Associate Investigator and P/F awardee in the previous application. She was recruited to the Department of Pediatrics at Boston University School of Medicine to head the Division of Pediatric Nutrition and develop a multidisciplinary program that targets underserved children and adolescents who are overweight or obese, particularly of minority background. As a result of the P/F award in 2000 to study glutamine metabolism in obese adolescents, Dr. Lenders has used data derived from the Nurse's Health Study and Grow Up Study Database at the Channing Laboratory and from a multicenter drug weight loss study as the basis for an application to the NIDDK and as a thesis for her doctoral degree (Sc.D.) in Nutritional Epidemiology at HSPH. She has extensive foundation support for interventions aiming at prevention and treatment of obesity and associated complications among inner city children.
Susan Roberts
Dr. Roberts continues as an Investigator in the HCNRC renewal. She is an international expert on energy regulation and obesity. Her lab at the USDA Center on Nutrition and Aging investigating the effects of different dietary compositions on voluntary energy intake and the ability to consume weight both when diets are provided and when dietary prescriptions are recommended. The underlying mechanisms for why different diets allow for different rates of weight loss (mediated by differences in hunger, satiety, palatability, energy expenditure, etc, and underlying metabolic mechanisms) are being explored. In addition, Dr Roberts’ lab studies the energy dysregulation of old age, specifically quantifying loss of energy intake and energy expenditure mechanisms, and their practical implications.
Stavroula Osganian
Dr. Osganian joins the HCNRC renewal as a new Investigator and as consultant in clinical research activities at CH. She trained in pediatrics at Boston Floating Hospital but quickly became interested in pediatric public health. After obtaining an MPH from the University of Massachusetts, she finished a ScD at the HPSH in 2000 and joined the faculty at HMS and Children’s Hospital in 2001. She currently heads the Clinical Research Program at CH and plans research in major problems in pediatric public health, including obesity through the GCRC at CH. Her primary interest is in finding ways to prevent excessive weight gain leading to obesity in adolescents through community and school-based intervention. Dr. Osganian collaborates with Drs. Ludwig, Grand, Duggan and Peterson.