Contact
Biography
Professor John Brameld
Professor of Nutritional Biochemistry
John's research interests fall into three main areas: molecular nutrition, development of body composition and regulation of energy balance. Current research projects include:
- Effects of vitamin D on cell growth, metabolism and gene expression.
- Regulation of tissue (muscle, fat and liver) growth and metabolism, combining metabolomics, transcriptomics and systems biology.
- Novel regulators of energy expenditure and appetite.
- Alternative protein sources and gut digestibility, including in vitro digestion models
Expertise Summary
Skeletal muscle; adipose tissue; liver; hypothalamus; metabolism; growth; energy expenditure; appetite.
Gene expression; microarrays; transcriptomics.
In vitro and in vivo studies.
Teaching Summary
I am the module convenor for the 2nd year undergraduate module, BIOS2036 (Nutrition, metabolism & disease), and the MSc modules BIOS4069/ 4089 (Fundamentals of Nutrition) and BIOS4068 (Nutrition… read more
Research Summary
My Research interests are predominantly the study of interactions between hormones and nutrients in the regulation of growth, development and metabolism, particularly of liver, skeletal muscle and… read more
I am the module convenor for the 2nd year undergraduate module, BIOS2036 (Nutrition, metabolism & disease), and the MSc modules BIOS4069/ 4089 (Fundamentals of Nutrition) and BIOS4068 (Nutrition & metabolism).
I teach on the following modules throughout the 3 years of the undergraduate BSc degree courses:
- BIOS1062 - Fundamentals in Food Science and Nutrition
- BIOS1067 - Sustainable Agriculture, Food and Nutrition
- BIOS2036 - Nutrition, Metabolism & Disease
- BIOS2038 - Nutritional Regulation, Physiology and Endocrinology
- BIOS2034 - Principles of Animal Nutrition
- BIOS3029 - Animal Nutrition
- BIOS3030 - Molecular Nutrition
I also teach on the following MSc Nutritional Sciences/ Animal Nutrition modules:
- BIOS4069/ BIOS4087 Fundamentals of Nutrition
- BIOS4068 Nutrition and Metabolism
- BIOS4067/ BIOS4088 Molecular Nutrition
Current Research
My Research interests are predominantly the study of interactions between hormones and nutrients in the regulation of growth, development and metabolism, particularly of liver, skeletal muscle and adipose tissue. I previously spent some time in the pharmaceutical industry and this has influenced the direction of my studies, which fall into 3 broad areas:
1) Molecular Nutrition.
These are all cell culture-based studies investigating the mechanisms by which specific nutrients influence gene expression.
- Past studies investigated the effects of glucose and amino acids on expression of genes of the growth hormone-insulin like growth factor (GH-IGF) axis. We demonstrated interactions between various hormones (insulin, thyroid hormones, glucocorticoids and growth hormone) and specific nutrients (glucose and individual amino acids) in the regulation of expression of growth hormone receptor (GHR) and IGF-I mRNA using cultured pig hepatocytes.
- Other studies in this area include i) effects of fatty acids on expression of key fat metabolism genes (e.g. stearoyl coA desaturase, SCD); ii) effects of plant-derived polyphenols (e.g. flavonoids) on vascular endothelial cell growth and gene expression, including microarray analyses; and iii) effects of fatty acids and oxidants/antioxidants on proliferation and differentiation of cultured muscle cells.
- More recent studies are investigating the effects of nuclear hormones/vitamins (e.g. vitamin A and D) on gene expression in different cell types, as well as effects on differentiation of muscle cells, including the conversion (so called trans-differentiation) to other cell types (e.g. adipose and bone).
2) Development of body composition.
The GH-IGF axis plays a key role in regulating the growth and differentiation of virtually all cell types, but particularly skeletal muscle and adipose tissue. The effects of nutrients on the GH-IGF axis may be particularly important during fetal life when skeletal muscle (myoblast/myofibre) and fat cell (preadipocyte/adipocyte) determination, proliferation and/or differentiation takes place.
- Previous studies investigated the effects of maternal nutrition on muscle and fat cell growth and development, and the long-term consequences for growth, development and metabolism of the offspring.
- Of particular interest has been the effect of maternal nutrition on body composition, muscle fibre number and fibre type composition of the offspring, combining molecular and histochemical methodologies in a variety of animal model systems.
- This was extended to investigate the regulation of skeletal muscle fibre type transitions during postnatal development, using a combined transcriptomic and metabolomic approach. This work has been in collaboration with a major pharmaceutical company.
3) Energy balance and efficiency.
The regulation of energy balance (intake vs expenditure) and nutrient partitioning is important both in terms of body composition and efficiency of growth in farmed animals, but also humans developing obesity and associated co-morbidities (insulin resistance, hypertension, etc).
- In vitro studies include the effects of hormones and nutrients (e.g. glucose and polyphenols) on fat breakdown (lipolysis) using cultured fat explants from pigs, rats and humans.
- In vivo studies investigate the regulation of appetite and whole body energy expenditure (oxygen consumption) using closed- and open-circuit calorimeters (e.g. CLAMS), including the effects of hypothalamic neuropeptides such as TRH, AgRP and VGF, as well as dietary polyphenols and plant extracts. The role of skeletal muscle characteristics (e.g. fibre number and type) in whole body energy expenditure is of particular interest, including the peripheral and central effects of nuclear hormone receptors and associated ligands (e.g. thyroid hormone, vitamin A and D and PPARs).
4) Alternative protein sources and gut digestibility
As part of the Future Protein Platform, we have been evaluating the nutritional value and digestibility of various plant (e.g. Winged Bean and Bambara Groundnut), single cell proteins (e.g. methanogenic bacteria) and insects (e.g. mealworms, crickets and black soldier fly larvae).
- Nutritional value includes protein, energy and fat contents, amino acid and fatty acid profiles and mineral contents, as well as levels of anti-nutritional factors (ANFs), such as phytate, tannins, polyphenols and digestive enzyme. inhibitors.
- The INFOGEST in vitro digestion model is used to evaluate protein and amino acid digestibilities, including comparisons with in vivo measurements