Metabolomics by In Vivo NMR

In vivo NMR of metabolites has built upon classical metabolic pathways to revolutionize our understanding of metabolism. In this book in vivo studies of metabolic fluxes in human muscle, heart and liver have utilized Metabolic Control Analysis (MCA) to relate metabolism to higher–level physiological functions. These novel approaches have located the genetic defect of Type II diabetes in recruitment of the muscle glucose transporter during glycogen synthesis, and have evaluated effects of diet and exercise upon this crucial step.

Flux control in muscle serves to guide interpretations of glucose consumption in the heart, and in yeast suddenly faced with more glucose than they need to oxidize. NMR studies show how reverse flows, so called "futile cycling" play an important role for yeast in these transient conditions. Isotopomer analysis of labelling data show how in vivo pathway fluxes can be obtained from body fluids in ways capable of high throughput.

In contrast to unproven hopes of going from metabolites directly to organismic function, this book moves by in vivo NMR from the molecules of metabolism to the conditions set by systemic physiology. This book will appeal to all readers looking for information on the following topics:

Up to date methodology and applications of in vivo NMR spectroscopy; Basic description of Metabolic Control Analysis, integrated with in vivo 13C and 31P NMR spectroscopy; Modern usage of stable isotope labeling, detected by NMR; in humans and animals Experiments illustrating these new methods exploring the metabolism in muscle, liver and heart; Yeast giving broad illustrations of alternate glucose pathways; Studies of yeast spores showing the energetic role of trehalose; Isotopomer analysis is presented clearly so as to determine fluxes from 13C and 2H labeling.

This book will appeal to the medical, biochemical and physiological communities, particularly those members who wish to understand the metabolic basis of human functions in modern quantitative terms, and the methods of in vivo NMR and Metabolic Control Analysis which have provided these insights.

Contributors xi

Foreword xiii
Sir George K. Radda, Medical Research Council, UK

Section A: Background

1 Introduction 1
Robert G. Shulman

2 In Vivo NMR Spectroscopy Techniques; Direct Detection; MRS; Kinetics and Labels; Fluxes; Concentrations 7
Robin de Graaf

3 Metabolic Control Analysis for the NMR Spectroscopist 31
David A. Fell

Section B: 13C and 31P NMR Studies of the Regulation of Glucose Metabolism

4 MRS Studies of the Role of the Muscle Glycogen Synthesis Pathway in the Pathophysiology of Type 2 Diabetes 45
Gerald I. Shulman and Douglas L. Rothman

5 Phosphorylation of Allosteric Enzymes can serve Homeostasis rather than Control Flux: the Example of Glycogen Synthase 59
James R.A. Schafer, David A. Fell, Douglas Rothman and Robert G. Shulman

6 Regulation of Glycogen Metabolism in Muscle during Exercise 73
Thomas B. Price

7 13C NMR Studies of Heart Glycogen Metabolism 87
Maren R. Laughlin, Douglas L. Rothman and Robert G. Shulman

8 Bioenergetics Implication of Metabolic Fluctuation during Muscle Contraction 103
Thomas Jue

9 Lactate, Glycogen and Fatigue 125
Robert G. Shulman and Douglas L. Rothman

10 Futile Cycling in Yeast: How to Control Gluttony in the Midst of Plenty 137
Jan den Hollander and Robert G. Shulman

11 Trehalose Energetics in Yeast Spores 149
Robert G. Shulman and Jan den Hollander

12 Metabolic Networks in the Liver by 2H and 13C NMR 159
A. Dean Sherry and Craig R. Malloy

13 Summarized Reflections on Metabolism 175
Robert G. Shulman and James R. A. Schafer

Index 185

Editors: Robert G. Shulman and Douglas L. Rothman, Yale University School of Medicine, New Haven, Connecticut, USA