Faculty

  • John Wysolmerski

    Acting Section Chief

    Professor of Medicine (Endocrinology)

    Education
    MD, Yale University, 1986; BS, Yale University, 1982

    Dr. Wysolmerski is an endocrinologist involved in patient care, medical education and medical research. He is a Professor of Medicine and serves as Associate Section Chief for Research in the Section of Endocrinology and Metabolism. He also serves as Director of the Yale Physician-Scientist Residency Program in the Internal Medicine Department. He sees adult patients with all endocrine disorders in the hospital and his outpatient clinical practice centers on disorders of mineral and bone metabolism. He treats patients with osteoporosis, osteomalacia, hyperparathyroidism, hypoparathyroidism, osteogenesis imperfecta, hypercalcemia, hypocalcemia and disorders of phosphate metabolism. His research focuses on the biological functions of parathyroid hormone-related protein in the breast and the regulation of calcium and bone metabolism during lactation and in breast cancer.

  • Sampada Chande

    Postdoctoral Fellow

    I am a postdoc associate at Bergwitz lab. I completed my PhD in Biotechnology at the National Environmental Engineering Research Institute (NEERI) in Nagpur, India and started as a postdoc at Yale school of medicine with Dr.Clemens Bergwitz in 2015. I am currently studying endocrine and metabolic regulation of phosphate by developing target gene specific expression plasmids (with epitope tag) and expressing it in various cell lines. The next step would be in vivo studies in the transgenic mice. Aim is to understand regulation of phosphate homeostasis.


  • Associate Research Scientist in Medicine (Endocrinology)

    Education
    PhD, China Agricultural University, 2004; MS, Agriculture University of Hebei, 1997; BS, Agriculture University of Hebei, 1994
  • James Dziura

    Professor of Emergency Medicine; Deputy Director, Yale Center for Analytical Sciences; Deputy Director, Yale Data Coordinating Center

    Education
    PhD, Yale University, 2001; MPH, Yale University, 1998; BS, Bates College, 1993

    Jim is a Professor in the Department of Emergency Medicine at YMS. As a biostatistician at Yale since 2002 he has co-authored over 160 peer-reviewed articles with a diverse group of Yale investigators. Dr. Dziura also serves as the Deputy Director of both the Yale Center for Analytical Sciences (YCAS) and the Yale Data Coordinating Center (YDCC) in the Yale School of Public Health. He has been active in training young investigators, both individually (as a mentor and statistical resource for K-awardees, post-doctoral fellows, residents and Master’s students) and in the classroom (where he has developed a graduate-level course and several workshops on biostatistics in clinical research). His primary research interests are in the coordination of multicenter clinical trials. Over the past ten years he has overseen data coordinating and biostatistical efforts for several trials. Notably, he served as the PI of the data coordinating center for the RUPP Autism Network study of Guanfacine for the treatment of hyperactivity. He is the Director of the Data Coordinating Center for the Autism Biomarkers Consortium for Clinical Trials (ABC-CT), a multicenter longitudinal study developing reproducible experimental biomarkers (e.g. from EEG, eye tracking) for use as stratification factors and outcomes in clinical trials.He is a senior biostatistician (and unblinded statistician for the DSMB) for the Data Coordinating Center of a large pragmatic cluster-randomized trial for the prevention of serious fall injuries (STRIDE) in 6,000 older persons from 86 health care practices.

  • Clare Flannery

    Associate Professor Term; Co-Director, Yale University Reproductive Sciences Biobank (YURS)

    Education
    MD, Trinity College, Dublin Ireland, 2001; BA, Wellesley College, 1995

    Dr. Flannery received her undergraduate degree in Chemistry from Wellesley College in 1995 before obtaining her M.D. degree from Trinity College, Dublin in Ireland in 2001. She completed internship in medicine and surgery at St. James’s Hospital in Dublin Ireland, and then Internal Medicine residency in the Women’s Health Track at Jacobi Hospital, Albert Einstein College of Medicine in the Bronx, NY. She was selected to be Chief Resident in Internal Medicine in 2005-2006. She then went on to the Yale University School of Medicine for her fellowship in Endocrinology & Metabolism. After becoming board certified in Internal Medicine and Endocrinology, she pursued a research fellowship at Yale, and worked in the laboratory of Dr. Gerald Shulman and Dr. Kitt Petersen on the pathophysiology of Type-2 Diabetes Mellitus. Then she focused her research on the effect of diabetes on endometrial pathology, with the mentorship of Dr. Hugh Taylor. She was awarded an NIH mentored career award then NIH R01 funding. She is an Assistant Professor with dual appointments in the Department of Obstetrics, Gynecology, and Reproductive Sciences (Reproductive Endocrinology) as well as Internal Medicine (Endocrinology). Her research involves studies on the link between obesity and endometrial pathology, including endometrial cancer and infertility. She sees patients with diabetes and endocrine disorders, with a specialty interest in diabetes prevention, Polycystic Ovary Syndrome, and transgender hormone therapy.

  • Kevan Herold

    C.N.H. Long Professor of Immunobiology and of Medicine (Endocrinology)

    Education
    MD, Jefferson Medical College, 1979; BS, Pennsylvania State University, 1977

    My background and research are in translational immunology. I am interested in understanding the basis for autoimmune diseases and developing new therapies based on our understanding of disease mechanisms. My focus has largely been in the field of autoimmune Type 1 diabetes. The work encompasses basic laboratory work understanding the regulation of autoreactive T cells to clinical trials that involve novel therapeutics. As part of these studies I have also been very interested in analysis of beta cell function in Type 1 diabetes.

  • Raimund Herzog

    Associate Professor Term

    Education
    MHS, Yale University, 2012; MD, Ulm University, Germany, 1998

    Dr. Raimund Herzog is an Assistant Professor in Endocrinology at Yale School of Medicine. He received his M.D. from University of Ulm, Germany before moving to the US, where he pursued his training in Internal Medicine at Yale School of Medicine. He earned his M.H.S. in the YCCI Junior Faculty Scholars program while further specializing in Endocrinology at Yale. In addition to caring for patients at the Yale Diabetes Center and teaching medical students Dr. Herzog maintains an active translational research program. A physician scientist with a strong interest in neuroscience and diabetes, Dr. Herzog’s laboratory is focused on characterizing and preventing its central nervous complications. He uses state-of-the-art technologies like in vivo NMR spectroscopy and phospho-proteomics to define the impact of diabetes and intensive insulin treatment on brain metabolism and cognition. His work extends from cell culture and animal models all the way to translation of findings to human subjects. It has produced novel insights into the molecular mechanisms underlying brain energy substrate metabolism thereby laying the basis for the development of targeted therapies that will protect the brain from diabetes complications and injury. In a related area Dr. Herzog’s workgroup has engaged in several collaborative projects that apply his understanding of metabolism towards more comprehensive and unbiased metabolomic analysis of peripheral plasma metabolites in an obese and diabetic adolescent cohort. Furthermore he is exploring the role of circulating small molecules and lipids in the context of aging-related cognitive decline in a cohort of elderly subjects. As part of his studies he has established a close working relationship with the Magnetic Resonance Research Center, Keck Mass Spectrometry Center and the Biostatistics Resource at Yale. His studies are funded by several NIH and private foundation awards and have resulted in high impact publications in journals like The Journal of Clinical Investigation, Diabetes and Endocrinology.

  • Janice Jin Hwang

    Assistant Professor of Medicine (Endocrinology)

    Education
    MHS, Yale University, 2017; MD, Harvard Medical School, 2006; AB, Princeton University, 2001

    Dr. Hwang is an endocrinologist as well as an Assistant Professor in the Division of Endocrinology at the Yale School of Medicine. She graduated magna cum laude from Princeton University in 2001 with a major in molecular biology followed by Harvard Medical School in 2006. She completed her residency training in Internal Medicine at the Beth Israel Deaconess Medical Center in Boston, MA and also served as a Chief Medical Resident. Dr. Hwang received her fellowship training in Endocrinology and Metabolism at Massachusetts General Hospital and moved to Yale in 2012 to continue her research training. Her academic interests are at the intersection of metabolism, neuroscience and imaging. Her research focuses on using advanced brain imaging modalities such as functional MRI and magnetic resonance spectroscopy coupled with classic investigative techniques in metabolism to understand the effects of diabetes and obesity on the central nervous system. Her research has been supported by the National Institutes of Health, the Yale Diabetes Research Center, the Endocrine Fellows Foundation, and the American Diabetes Association. She is the recipient of several awards for her research including most recently the Marilyn Fishman Award for Diabetes Research, the Metabolism Junior Investigator award as well as a Yale Center for Clinical Investigation Junior Faculty Scholars Award.

  • Karl Insogna

    Ensign Professor of Medicine (Endocrinology); Director, Yale Bone Center; Ensign Professor of Medicine without Term; Associate Director, Yale Center for X-Linked Hypophosphatemia

    Education
    MD, University of Connecticut, 1976

    Dr. Karl Insogna is a tenured Professor at Yale and an internationally recognized expert in the field of metabolic bone disease. He has published widely on the topic in the field's leading scientific journals, is quoted often in the lay press, and has frequently appeared on radio and television. He is a Fellow of the American Association for the Advancement of Science, and was a member of the National Institutes of Health Consensus Conference, which established new recommendations for the optimal level of calcium intake for all Americans - now adopted nationwide. He is a leading researcher in the causes of bone loss in such diseases as osteoporosis and primary hyperparathyroidism, and is currently conducting studies in, among other areas, the role of diet in the development of osteoporosis.

  • Silvio Inzucchi

    Professor of Medicine (Endocrinology)

    Education
    MD, Harvard University, 1985; BS, Fordham University, 1981

    Dr. Inzucchi received his undergraduate degree from Fordham University in the Bronx, NY and his M.D. degree from Harvard Medical School in Boston, MA. He completed his internship and residency in Internal Medicine and his post-doctoral Fellowship in Endocrinology and Metabolism at Yale-New Haven Hospital, in New Haven, CT. Dr. Inzucchi has authored or co-authored over 250 manuscripts, monographs, textbook chapters, and abstracts, and has lectured at a national and international level on a wide variety of endocrine topics. Dr. Inzucchi has a large academic clinical practice involving a broad spectrum of patients with endocrine diseases. His specific
    clinical interests include diabetes as well as pituitary/adrenal disorders. His current research involves studies on the link between type 2 diabetes, insulin resistance, and cardiovascular complications; management of hyperglycemia in the hospital; and diagnostic criteria for diabetes and related conditions.

  • Ania Jastreboff

    Assistant Professor of Medicine (Endocrinology) and of Pediatrics (Endocrinology); Director, Weight Management & Obesity Prevention; Medical Director, Yale Stress Center

    Education
    PhD, Yale University Graduate School of Arts and Sciences, 2011; MD, University of Maryland at Baltimore, 2002; BA, Bucknell University, 1998

    Dr. Jastreboff is an adult and pediatric endocrinologist at Yale School of Medicine with expertise in obesity medicine and weight management. Additionally, she cares for patients with prediabetes, insulin resistance, metabolic syndrome, type 1 and type 2 diabetes. Dr. Jastreboff is board certified in Internal Medicine, Pediatrics, Endocrinology and Metabolism, Pediatric Endocrinology, and Obesity Medicine.

    She completed her PhD at Yale University's Investigative Medicine Program focused on translational and clinical investigation with a dissertation entitled “Neural Response to Food Cues and Stress in Obese Individuals".

    Dr. Jastreboff is currently supported by NIH/NIDDK K23 award to study insulin’s effect on the brain in obese individuals utilizing fMRI in combination with hyperinsulinemic-euglycemic clamps.

  • Elizabeth Jonas

    Professor of Internal Medicine (Endocrinology) and Neuroscience

    Education
    MD, New York University, 1986; BA, Yale University, 1982

    Elizabeth Jonas received training in Neurology and Internal Medicine. She developed an interest in Neuroscience while studying as a medical student with Dr. Rodolfo Llinas at N.Y.U. and at the Marine Biological Laboratory. With Dr. Llinas she developed an interest in calcium control of synaptic transmission. She pursued this interest as a post-doctoral fellow in the laboratory of Dr. Leonard Kaczmarek, Yale Pharmacology. Dr. Jonas developed a technique for recording from ion channels on intracellular membranes and has used this and other techniques to study mitochondria. Mitochondria are necessary for life and death of neurons and other cells. Regulation of mitochondrial metabolism is also key to energy efficiency in the nervous system. Dr. Jonas is now studying the role of mitochondria and energy efficiency in neurodegenerative disease states and in learning and memory formation in healthy brain. Her lab has recently characterized the molecular identity of the cell death channel known as the mitochondrial permeability transition pore and is now studying how inhibiting gating of the pore may ameliorate stroke, neurodegenerative and developmental brain diseases.

  • Richard Kibbey

    Associate Professor of Medicine

    Education
    MD/PhD, University of Texas Southwestern Medical School, 2000; BS, Trinity University, 1991; BA, Trinity University, 1991

    Dr. Kibbey obtained his undergraduate degrees in music (B.A.) and an honors degree in biochemistry (B.S.) at Trinity University in San Antonio in 1991. He then obtained his combined M.D. and Ph.D. at the University of Texas Southwestern Medical School in 2000. His Ph.D. was in Cellular and Molecular Biophysics and involved determining the NMR structure of peptides from the LDL receptor under his mentors Drs. R.G.W. Anderson and L. Gierasch. Subsequently, he went to Yale University in where he was selected for the ABIM short-track in Categorical Internal Medicine. In 2002 he stayed on for his Endocrinology fellowship at Yale and is now board certified in Internal Medicine and Endocrinology. While in his fellowship he worked in the laboratory of Dr. Gerald Shulman on metabolism in the pathophysiology of Type-2 Diabetes Mellitus. Here he identified mitochondrial GTP as a metabolic signal in the mitochondria sensing flux in the pancreatic beta-cell as a crucial component of the signal to secrete insulin. His laboratory also has developed a novel platform using stable isotopes and mass spectrometry named Mass Isotopomer MultiOrdinate Spectral Analysis (MIMOSA) that measures the flow of metabolism inside and between tissues. He is now an Associate Professor in the Departments of Internal Medicine/Endocrinology and Cellular & Molecular Physiology. He continues to see patients at Yale Health and has an independent NIH-supported laboratory doing research on islet and whole body physiology in order to understand/prevent/treat Type-2 diabetes.

  • Grace Lee

    Assistant Professor of Medicine (Endocrinology)

    Education
    MD, New York University School of Medicine, 2007; BS, University of California at Los Angeles, 2002

    Dr. Lee received her undergraduate B.S. degree from UCLA in Los Angeles, CA and her M.D. degree from New York University School of Medicine in New York, NY. She completed her internship and residency in Internal Medicine as well as her fellowship in Endocrinology and Metabolism at Yale-New Haven Hospital in New Haven, CT. Dr. Lee has a clinical practice that treats patients with metabolic bone disease, thyroid nodules, thyroid cancer, adrenal disease, and pituitary disease.

  • Kasia Lipska

    Assistant Professor of Medicine (Endocrinology)

    Education
    MHS, Yale University School of Medicine, Robert Wood Johnson Clinical Scholars Program, 2011; MD, Harvard Medical School, 2003; BS, Yale University, 1997

    Dr. Lipska is an endocrinologist at the Yale School of Medicine and a Clinical Investigator at the Yale-New Haven Hospital Center for Outcomes Research and Evaluation (CORE). Her research program seeks to better understand the balance of benefits and harms of glucose-lowering therapy in older adults with type 2 diabetes. Her current research projects are primarily focused on severe hypoglycemia. She is investigating trends in admissions for hypoglycemia among the elderly Medicare population; race, sex, and age disparities in these admissions; using qualitative research methods to explore reasons for hypoglycemia admissions; examining key risk factors for hypoglycemia; and developing prediction models for hypoglycemia. Based on these data, she seeks to develop and implement decision support tools to help clinicians and patients make better decisions about their care. Her overall goals are to generate data that patients and clinicians need—data which currently do not exist—so that they can make better, smarter treatment decisions.

    In addition, Dr. Lipska works at CORE on the development of ambulatory care quality measures for the Centers for Medicare & Medicaid Services (CMS). She is currently leading the development of an outcome measure of care quality among people with diabetes mellitus.

    YCCI Scholar 2013

    Project: 11/01/13 - 10/31/15

    Treatment-Related Determinants of SevereHypoglycemia in Type 2 Diabetes

  • My lab is involved in the study of a heredity form of osteomalacia (rickets in children) called X-linked hypophosphatemia (XLH). While XLH is characterized by defective bone mineralization, a paradoxical and severe mineralizing enthesopathy (entheses are tendon and ligament insertion sites) develops in many adult patients. We have made significant progress in understanding the pathogenesis of the enthesopathy of XLH, as reported in our most recent publication (G Liang, LD Katz, KL Insogna, TO Carpenter, CM Macica. A Study of the Enthesopathy of X-linkedHypophosphatemia. Calcified Tissue International, Volume 85 (3) 235-242, 2009). Here, we describe the first comprehensive patient survey of the enthesopathy of XLH, which provided valuable insight into the pathogenesis of the enthesopathy. In this study, we utilized the Hyp mice, the murine model of XLH. Indeed, we have identified the Hyp mouse as the first valid model of enthesopathy by examining those fibrocartilagenous insertion sites most frequently targeted in the XLH patient population studied. The primary histologic feature of the enthesopathy of the Achilles and patellar insertion sites in the Hyp mouse was a dramatic cellular expansion and thickening of mineralized enthesis fibrocartilage. We have thus identified an enthesopathy in Hyp mice that closely phenocopies the human disease. We also provide the first evidence that an expansion of mineralized fibrocartilage may define the enthesopathy and is not due to ectopic osteoblast-driven bone formation, as previously thought. We additionally found that fibrocartilage cells express the fibroblast growth factor receptor FGFR3, as well as the co-receptor, Klotho. This finding suggests that the high circulating levels of FGF-23, characteristic of XLH and Hyp mice, (and an FGFR3 ligand), may be part of the biochemical milieu that underlies the expansion of mineralizing enthesis fibrocartilage. Because the pathology of XLH enthesopathy and of age and use-dependent injuries to tendon and ligament insertion sites all involve excessive mineralization or “hardening” of these sites, our newest data focuses on the molecules that regulate this process. Analysis of enthesis and articular cartilage alkaline phosphatase (ALP) activity, the enzyme that catalyzes the deposition of mineral, revealed significantly higher levels of activity in Hyp mice during periods of both growth and adulthood. This is consistent with the elevated serum ALP activity reported in patients with XLH and in Hyp mice, a finding we have confirmed. Immunohistochemical analysis of ALP protein suggests the presence of two biochemically distinct isoforms of ALP that we refer to as osteoblast ALP and chondrocyte ALP. We propose that because articular cartilage and fibrocartilage are avascular, limited phosphoester substrate availability would favor an enzyme with a low Michaelis constant (Km) for phosphoester substrates. This, along with an increase in ALP activity, may account for the ability of chondrocytes to hypermineralize in a rachitic environment. We are working in collaboration with the Keck facility at Yale to characterize the alkaline phosphatase enzyme we have isolated from the long bones of Hyp mice. Finally, mineralizing fibrocartilage cells and articular cartilage specifically express osteopontin (OPN), a highly phosphorylated osteoblast glycoprotein, the levels of which are regulated by extracellular pyrophosphate (ePPi). It has recently been shown that phosphorylated OPN and ePPi act together to synergistically inhibit mineralization. We found that while OPN levels are highly elevated in osteoblasts of Hyp mice, OPN is absent in the mineralized cartilage of Hyp mice. We speculate that, together with the increase in ALP activity, the loss of OPN from cartilage might underlie the hypermineralization of cartilages by reducing inhibitory constraint of OPN, explaining the paradox of inappropriate mineralization of cartilage tissue in a rachitic environment.

  • Asst Clin Prof Int Med Endocrinology

    Education
    MD, Warsaw University, 1985

    Dr. Urszula Masiukiewicz is an Assistant Clinical Professor of Medicine at Yale School of Medicine and an attending physician at Yale New-Haven Hospital. She obtained her medical degree from Warsaw Medical School, Warsaw, Poland, and completed postgraduate training at the National Institute of Cardiology in Warsaw, Poland and internal medicine residency at the University of Massachusetts-Memorial Medical Center, Worcester, Massachusetts. In 1996 Dr. Masiukiewicz joined Yale University as a fellow in endocrinology and rose to the rank of Assistant Professor. Dr. Masiukiewicz is a Senior Director in Cardiovascular and Metabolic Division at Pfizer, where she has conducted clinical research since 2004. Dr. Masiukiewicz is a part time clinical faculty member at Yale University and has clinical interests in postmenopausal osteoporosis, disorders of calcium metabolism, metabolic bone disease and thyroid disease.

  • Nelli Mnatsakanyan

    Assistant Professor

    Education
    PhD, Yerevan State University, 2003; MS, Yerevan State University, 1999; BS, Yerevan State University, 1999

    My long-term scientific interest is to study the structure-function relationship, regulation and clinical significance of membrane proteins. My early research project in Dr. Joachim Weber's group was focused on investigating the catalytic mechanism and chemo-mechanical coupling in ATP synthase. Later, I pursued structural and functional studies on nicotinic acetylcholine, GABAA and other pentameric ligand-gated ion channels of neurotransmitter receptors. My current research focuses on the role of ATP synthase in mitochondrial permeability transition and its impact on neurodegenerative disorders, aging and cancer. I am using the cryo-electron microscopy and patch-clamp recording techniques to characterize the enigmatic "cell death" channel located in mitochondrial ATP synthase. In-depth structural analysis of ATP synthase will reveal its “open channel” conformation and may lead to structure-based drug design of specific therapeutic compounds for the treatment of degenerative disorders.

  • Rachel Perry

    Assistant Professor

    Education
    PhD, Yale University Graduate School, 2013; BS, Yale University, 2008

    Dr. Rachel Perry is an Assistant Professor in Medicine/Endocrinology and Cellular & Molecular Physiology at the Yale University School of Medicine. Rachel's background is in the use of hyperinsulinemic-euglycemic clamps and stable isotope infusions to assess insulin sensitivity, having earned her B.S. in Biomedical Engineering, Ph.D. (with Distinction) in Cellular & Molecular Physiology, and performed her postdoctoral training in Medicine/Endocrinology, all in the laboratory of Dr. Gerald Shulman. Rachel's CV includes first-author papers in Nature, Cell (2), Science, JCI, Nature Medicine (2), Nature Communications (3), JBC, Cell Metabolism (2), and AJP-Endocrinology. 

    Dr. Perry's laboratory focuses on applying stable isotope tracer methods to understand obesity-associated alterations in metabolic flux pathways that occur with obesity. She and her colleagues have recently identified hyperinsulinemia-induced increases in tumor glucose uptake and oxidation as a critical driver of colon cancer in two mouse models of the disease, and mitochondrial uncoupling as a potential therapeutic strategy against the disease (Wang et al. Cell Reports 2018). Future work from the Perry lab will seek to elucidate potential alterations in tumor immunometabolism that may contribute to tumor progression, and the impact of cancer therapy on substrate preference in immune cells.

  • Kitt Petersen

    Professor of Medicine (Endocrinology)

    Education
    MD, University of Copenhagen, 1985

    Dr. Petersen is Professor of Internal Medicine, Section of Endocrinology, Yale University School of Medicine, Honorary Professor of Medicine and Clinical Physiology at University of Copenhagen, Deputy Director of the Metabolic Imaging and Liver Metabolism Section at the Center for Basic Metabolic Research, Copenhagen University, Denmark.

    Dr. Petersen received her bachelor’s degree from N. Zahle’s Gymnasieskole (majors: math & physics) in Copenhagen (1978) and her MD from the University of Copenhagen (1985), completed clinical training at the university hospitals, Copenhagen followed by the prestigious fellowships: Kandidat- and Seniorstipendiums for research in metabolism at the University of Copenhagen (1986-1991).

    In 1990 Dr. Petersen received further fellowship and postdoctoral training at Yale University in magnetic resonance (MR) spectroscopy and metabolism. At Yale University School of Medicine she became Research Scientist at in 1991, Assistant Professor in 1998, Associate Professor in 2004 and Professor in 2012.

    She has received prestigious awards for her clinical research, including:

    • Henry Christian Award for Excellence in Clinical Research (1997, 1998, 2004)
    • Novartis Young Investigator Award for Excellence in Clinical Research in Diabetes (2002)
    • Glaxo Smith Kline Scholar Award (2003)
    • Distinguished Clinical Scientist Award from the American Diabetes Association (2009)
    • Team Science Award, Association for Clinical and Translational Science (2016)

    Dr. Petersen has published over 140 articles using stable isotopes MR spectroscopy to explore the pathogenesis of NAFLD, type 2 diabetes, insulin resistance in aging, obesity, and low birth weight and the reversal of NAFLD and insulin resistance with caloric restriction or exercise.

  • Robert Sherwin

    C.N.H. Long Professor Emeritus of Internal Medicine (Endocrinology)

    Education
    MD, Albert Einstein College, 1967; BS, Union College, 1963

    Robert S. Sherwin. MD is the C.N.H. Professor of Medicine in the Section of Endocrinology at Yale School of Medicine in New Haven, CT. He graduated from the Albert Einstein College of Medicine in 1967. After his residency in internal medicine at Mount Sinai Hospital (N Y), he served as a research fellow in metabolism and diabetes at the National Institutes of Health. In 1972 Dr Sherwin moved to Yale University School of Medicine where he was a postdoctoral fellow and subsequently was appointed to the faculty in 1974. He currently serves Chief of the Section of Endocrinology as well as the Director of the CTSA-funded Yale Center for Clinical Investigation and the NIDDK-funded Diabetes Research Center at Yale. His special clinical interests include patients with type 1 diabetes, intensified insulin therapy, complicated type 2 diabetes patients, and hypoglycemia associated with diabetes. Dr Sherwin’s research activities span clinical and basic research and are focused on brain glucose sensing mechanisms mediating the activation of counterregulatory responses and the impact of hypoglycemia and insulin on brain function and metabolism as well as the changes in brain function that drive disordered glucose control and eating behavior using brain imaging techniques (fMRI, spectroscopy, and PET) in both diabetes and obesity. Dr. Sherwin has served as President of the American Diabetes Association and as a member of the FDA Advisory Committee for Endocrinologic and Metabolic Drugs. He has served as the Chairman of the Medical Science Advisory Board of the JDRF and on the editorial boards of leading diabetes and endocrine journals. He has published over 400 articles in peer-reviewed journals and is the recipient of numerous scientific awards including the American Diabetes Association’s Banting Award for lifetime scientific achievement, the Novartis Award for long-standing achievement in diabetes, and 2 MERIT Awards from the NIH.

  • Gerald Shulman

    George R. Cowgill Professor of Medicine (Endocrinology) and Professor of Cellular And Molecular Physiology; Investigator, Internal Medicine; Co-Director, Yale Diabetes Research Center, Internal Medicine; Director, Yale Mouse Metabolic Phenotyping Center, Internal Medicine

    Education
    MD, Wayne State University, 1979; PhD, Wayne State University, 1979; BS, University of Michigan, Ann Arbor, MI, 1974

    Dr. Shulman is the George R. Cowgill Professor of Medicine, Cellular & Molecular Physiology and Physiological Chemistry at Yale University, where he serves as Co-Director of the Yale Diabetes Research Center. Dr. Shulman has pioneered the use of magnetic resonance spectroscopy to non-invasively examine intracellular glucose and fat metabolism in humans for the first time. Using this approach he has conducted ground breaking basic and clinical investigative studies on the cellular mechanisms of insulin resistance that have led to several paradigm shifts in our understanding of type 2 diabetes. Dr. Shulman has authored and co-authored over 450 peer-reviewed publications, and he has also trained more than 70 postdoctoral fellows and graduate students, many of whom now direct their own independent laboratories around the world. Dr. Shulman is a Master of the American College of Endocrinologists, Fellow of the American Association for the Advancement of Science and he has been elected to the American Society for Clinical Investigation, the Association of American Physicians, the American Academy of Arts & Sciences, the National Academy of Medicine and the National Academy of Sciences.

  • Ben-Hua Sun

    Associate Research Scientist in Medicine (Endocrinology)

    Education
    MD, Beijing Second Medical College, 1984; MS, Beijing Institute of Orthopaedics & Traumatology, 1982

    Ben-Hua Sun is from Beijing and came to the Insogna lab in 1994 as a postdoctoral fellow before joining the faculty as an Associate Research Scientist in 2000. He currently is the Insogna Laboratory Manager. His principal areas of expertise are whole-animal experimentation and in vitro models of osteoclastogenesis. He plays a major role in work exploring the mechanism by which thrombospondin 1 induces osteoclastogenesis. He also manages the microCT facility, which is part of the Physiology Core of the Yale Core Center for Musculoskeletal Disorders.

  • Daniel F Vatner

    Assistant Professor of Medicine (Endocrinology)

    Education
    MD, University of Chicago Pritzker School of Medicine, 2007; PhD, University of Chicago, 2005; BA, Swarthmore College, 1998

    Attending Physician, Endocrinology Service, VA Connecticut Healthcare System

    Endocrinology Service Phone: (203) 937 3848

    Fax: (203) 937 4784

  • Xian-Man Zhang

    Associate Research Scientist in Medicine (Endocrinology)

    Education
    PhD, Lanzhou University, 1989; MSc, Lanzhou University, 1987

    BIOGRAPHY

    Dr. Zhang has worked as a physical organic chemist/professor for near twenty years in various academia, industrial and national research laboratories. He has authored/co-authored over 70 scientific publications before joined Yale University in 2004. During the past decade, he mainly employed his broad chemistry knowledge and hands-on research experience to develop various practical analytical methods to characterize and quantitate any interesting metabolites in the related plasma/tissue biological samples using different analytical techniques. In the past few years, he and his analytical team has worked on many projects.

    1. Can we develop well-tolerated therapeutic agents to reverse hypertriglyceridemia, insulin resistance, non-alcoholic steatohepatitis and non-alcoholic fatty liver disease?

    A series of 2,4-dinitrophenol derivatives have been synthesized and characterized. Animal studies show that these novel chemicals are non-toxic and safe for in-vivo injections and are efficient mitochondrial protonophore to reverse diabetes and steatohepatitis in rats.

    2. Metformin suppresses gluconeogenesis by inhibiting mitochondrial glycerophosphate dehydrogenase.

    Metformin is considered to be one of the most effective therapeutics for treating type 2 diabetes because it specifically reduces hepatic gluconeogenesis without increasing insulin secretion, inducing weight gain or posing a risk of hypoglycaemia.

    3. Leptin reverses diabetes by suppression of the hypothalamic-pituitary-adrenal axis.

    The antidiabetic effect of leptin has been postulated to occur through suppression of glucagon production, suppression of glucagon responsiveness.

    4. How does inflammation contribute to insulin resistance and fasting hyperglycemia in diet-induced obesity in rodents and humans?

    Using a novel in vivo metabolomics approach, we show that the major insulin suppresses HGP mechanism is through reductions in hepatic acetyl CoA by suppression of lipolysis.

    Selected publications (from over 100 publications):

    1. R. J. Perry, D. Zhang, X.-M. Zhang, J. L. Boyer, and G. I. Shulman, “Controlled-release mitochondrial protonophore reverses diabetes and protonophore reverses diabetes and steatohepatitis in rats”, Science, 2015, 347(6227), pp1253-1256.
    2. Perry, R.J., Camporez, J.-P.G., Kursawe, R., Titchenell, P.M., Zhang, D., Perry, C.J., Jurczak, M.J., Abudukadier, A., Han, M.S., Zhang, X.-M., Ruan, H.-B., Yang, X., Caprio, S., Kaech, S.M., Sul, H.S., Birnbaum, M.J., Davis, R.J., Cline, G.W., Petersen, K.F., Shulman, G.I., “Hepatic acetyl CoA links adipose tissue inflammation to hepatic insulin resistance and type 2 diabetes”, Cell, 2015, 160(4), 745-758.
    3. Perry RJ, Borders CB, Cline GW, Zhang XM, Alves TC, Petersen KF, Rothman DL, Kibbey RG, Shulman GI., “Propionate Increases Hepatic Pyruvate Cycling and Anaplerosis and Alters Mitochondrial Metabolism”, J Biol Chem. 2016, 291(23):12161-70.
    4. A. Madiraju, D. M. Erion, Y. Rahimi, X.-M. Zhang, D. Braddock, R. A. Albright, B. J. Prigaro, J. L. Wood, S. Bhanot, G. W. Cline, V. T. Samuel, R. G. Kibbey, G. I. Shulman, “Metformin suppresses hepatic gluconeogenesis via inhibition of mitochondrial glycerophosphate dehydrogenase and modulation of the hepatocellular redox state”, Nature, 2014, 510(7506), pp542-546.
    5. R. J. Perry, X. M. Zhang, D. Zhang, N. Kumashiro, J. P. Camporez, G. Cline, D. L. Rothman, G. I. Shulman, Mechanism for the anti-diabetic effect of leptin. Nature Medicine, 2014, 20, 759-763.
    6. Mehra, V.C., Jackson, E., Zhang, X.M., Jiang, X.-C., Dobrucki, L.W., Yu, J., Bernatchez, P.,Sinusas, A.J., Shulman, G.I., Sessa, W.C., Yarovinsky, T.O., Bender, J.R. “Ceramide-activated phosphatase mediates fatty acid-induced endothelial VEGF resistance and impaired angiogenesis, American Journal of Pathology, 2014, 184, 1562-1576.
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