The goal of this program is understand the role of mitochondrial dysfunction on insulin resistance and other related metabolic disorders in humans. The program involves collaborative interactions between members of several departments, and is organized into three projects supported by three core facilities. Expertise in the fields of clinical physiology, biochemistry, human genetics, cell & molecular biology and nuclear magnetic resonance spectroscopy (MRS) will focus on the role of mitochondrial dysfunction in human disease. We will address the following questions: (1) Is mitochondrial dysfunction responsible for fat accumulation in muscle/liver and insulin resistance in young lean normorglycemic offspring of parents with type 2 diabetes (IR offspring), (2) What genes are responsible for reduced mitochondrial activity/content in IR offspring and families with hypertension and hyperlipidemia which appears to be due to a novel homoplasmic mutation in a mitochondrial tRNA/ile. (3) is brain mitochonddal metabolism affected in these patients as well as in insulin resistant elderly subjects? These questions will be addressed by collaborative interactions between the Principal Investigators of these 3 projects, which are as follows: (Project 1) - Dr. Shulman will address the role of mitochondrial dysfunction in the pathogenesis of insulin resistance in IR offspring. This project builds on preliminary data by his group demonstrating that these individuals have increased intramyocellular lipid content, which can be attributed to reduced mitochondrial activity. This project will further explore mitochondrial function in liver and muscle of these individuals using 13C/31p/1H MRS in combination with direct examination of muscle tissue by cellular and molecular approaches to directly quantify mitochondrial content, insulin signaling and protein phosphorylation using a novel LC/MSIMS approach, (Project 2) - Dr. Lifton will examine nuclear and mitochondrial DNA in muscle biopsy samples obtained from IR offspring and insulin sensitive control subjects that have been characterized in Project #1 in order to identify genes responsible for reduced mitochondrial function/content and insulin resistance. This project will examine the hypothesis that alterations in genes regulating mitochonddal biogenesis are responsible for insulin resistance. This project will also further characterize patients with hypertension and hyperlipidemia which preliminary data by his group suggests is caused by a novel homoplasmic mutation in a mitochondrial tRNA/ ile. (Project 3) - Dr, Rothman will employ novel C/31P MRS techniques to examine brain mitochondrial function in: 1) healthy elderly volunteers who have recently been shown to be insulin resistant due to mitochondrial dysfunction, 2) patients with the novel mitochondrial tRNA/ ile mutation associated with hypertension and hypedipidemia identified in Project 2, and 3) insulin resistant offspring of parents with type 2 diabetes identified in Project 1. These three projects will be supported by an Administrative Core (Core A) to coordinate the project as a whole, a Clinical Core (Core B) and a MRS/MRI Core (Core C). The program is coordinated by frequent meetings of the program faculty and research workers bdnging together these diverse approaches to address a common goal.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Program Projects (P01)
Project #
5P01DK068229-05
Application #
7493559
Study Section
Special Emphasis Panel (ZDK1-GRB-4 (M4))
Program Officer
Laughlin, Maren R
Project Start
2004-09-15
Project End
2010-08-31
Budget Start
2008-09-01
Budget End
2010-08-31
Support Year
5
Fiscal Year
2008
Total Cost
$1,410,977
Indirect Cost
Name
Yale University
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
043207562
City
New Haven
State
CT
Country
United States
Zip Code
06520
Madiraju, Anila K; Qiu, Yang; Perry, Rachel J et al. (2018) Metformin inhibits gluconeogenesis via a redox-dependent mechanism in vivo. Nat Med 24:1384-1394
Lee, Hui-Young; Gattu, Arijeet K; Camporez, João-Paulo G et al. (2014) Muscle-specific activation of Ca(2+)/calmodulin-dependent protein kinase IV increases whole-body insulin action in mice. Diabetologia 57:1232-41
Jornayvaz, François R; Shulman, Gerald I (2012) Diacylglycerol activation of protein kinase C? and hepatic insulin resistance. Cell Metab 15:574-84
Samuel, Varman T; Shulman, Gerald I (2012) Mechanisms for insulin resistance: common threads and missing links. Cell 148:852-71
Samuel, Varman T; Petersen, Kitt Falk; Shulman, Gerald I (2010) Lipid-induced insulin resistance: unravelling the mechanism. Lancet 375:2267-77
Petersen, Kitt Falk; Dufour, Sylvie; Hariri, Ali et al. (2010) Apolipoprotein C3 gene variants in nonalcoholic fatty liver disease. N Engl J Med 362:1082-9
Boumezbeur, Fawzi; Mason, Graeme F; de Graaf, Robin A et al. (2010) Altered brain mitochondrial metabolism in healthy aging as assessed by in vivo magnetic resonance spectroscopy. J Cereb Blood Flow Metab 30:211-21
Boumezbeur, Fawzi; Petersen, Kitt F; Cline, Gary W et al. (2010) The contribution of blood lactate to brain energy metabolism in humans measured by dynamic 13C nuclear magnetic resonance spectroscopy. J Neurosci 30:13983-91
Mitchell, Catherine S; Savage, David B; Dufour, Sylvie et al. (2010) Resistance to thyroid hormone is associated with raised energy expenditure, muscle mitochondrial uncoupling, and hyperphagia. J Clin Invest 120:1345-54
Befroy, Douglas E; Falk Petersen, Kitt; Rothman, Douglas L et al. (2009) Assessment of in vivo mitochondrial metabolism by magnetic resonance spectroscopy. Methods Enzymol 457:373-93

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