Linda J. Wykes

Associate Professor
William Dawson Scholar

Tel.: 514-398-7843
Fax: 514-398-7739
linda [dot] wykes [at] mcgill [dot] ca (Email)

Degrees

• BSc, Nutrition and Food Science, University of Toronto
• MSc, Nutritional Sciences, University of Toronto
• PhD, Nutritional Sciences, University of Toronto

Professional Memberships

• American Society for Nutritional Sciences
• American Society for Clinical Nutrition
• Canadian Society for Nutritional Sciences
• Canadian Society for Mass Spectrometry
• Montreal Stable Isotope Research Group
• Sigma Xi

Current Research

THEME 1 — MALNUTRITION AND METABOLIC STRESS

The overall goal of this theme is to investigate how adaptations to protein and/or energy malnutrition compromise the ability to respond to infective or inflammatory stress, and vice versa how metabolic stresses exacerbate malnutrition, growth retardation and muscle wasting. This negative spiral of malnutrition and infection has tremendous impact on many clinical conditions and in populations throughout the world. Adaptations to malnutrition are very difficult to study in humans because of the ethical imperative to treat once either malnutrition or an infection is diagnosed, because malnutrition is multifactorial in nature rarely restricted to deficiency of a single nutrient, and because an underlying pathology or subclinical infection is almost invariably present along with malnutrition. Therefore the mechanistic studies in animal models can provide a strong foundation for clinical studies to test new therapeutic approaches. These are the first stable isotope studies ever conducted in piglets.

1. Piglet Model of Inflammatory Bowel Disease
2. Effect of Chronic Protein Deficiency on Protein Synthesis
3. Adaptations to Protein Deficiency Compromise the Response to Systemic Inflammation
4. Interaction of Protein Energy Malnutrition and Gastrointestinal Inflammation
5. Strategies to Improve Nutrient Utilization and Minimize Catabolic Stress After Surgery (collaboration with Franco Carli, McGill)
6. Malnutrition and Parasitic Gastrointestinal Nematode Infection (collaboration with Kristine Koski and Marilyn Scott, McGill)

THEME 2 — ROLE OF AMINO ACIDS IN FETAL AND NEONATAL GROWTH AND DEVELOPMENT

1. Impact of Piglet Model of Total Parenteral Nutrition
2. Arginine in Total Parenteral Nutrition (collaboration with Louis Beaumier, McGill)
3. Intrauterine Growth Retardation (collaboration with Kristine Koski, McGill)

THEME 3 AMINO ACID METABOLISM: AMOUNT AND ROUTE OF ADMINISTRATION (ENTERAL VS PARENTERAL) OF AMINO ACIDS AFFECT AMINO ACID METABOLISM AND GUT PHYSIOLOGY

1. Role of the Intestine in Handling Dietary Amino Acids
2. Sulphur Amino Acid Metabolism (collaboration with John Hoffer, McGill)
3. Amino Acid Requirements by Indicator Amino Acid Oxidation (collaboration with Paul Pencharz, Hospital for Sick Children and Ron Ball, University of Alberta

THEME 4 - MATHEMATICAL MODELLING AND KINETIC METHOD DEVELOPMENT

This theme is a diverse application of some of stable isotope studies involving analysis of the pattern among mass isotopomers either of tracers or metabolites. I have used amino acid labelling pattern to study intermediary metabolism, dispensable amino acid synthesis, and the pattern of label incorporation into a protein to measure its rate of synthesis. These models were developed in piglets for application in humans.

1. Intermediary Metabolism
2. Tracer Protocols and Questions
3. Cholesterol Synthesis by Mass Isotopomer Distribution Analysis (MIDA).

Publications

To view a list of Dr. Wykes' publications, click here.