For the longest time we have been educated with the idea that food consists of substances that service the purpose of supply of structural building blocks (e.g. proteins), fuels (e.g. fats and carbohydrates), or protective mechanisms against deficiency disease (e.g. vitamins and minerals). Also we may have learned that hormones are a limited group of powerful molecules, produced and secreted by glands, transported through blood circulation, functioning as messenger molecules through receptors. Structure-wise, the main groups here: the peptide hormones (e.g. insulin) and the steroid hormones (e.g. cortisol or testosterone).
Recent developments in molecular and genomic biochemistry lead us to the insight that food components act as hormones as well! And we are not talking about the hormonal contamination as in meat and many other foods.
The discovery of new transcription factors and nuclear receptor proteins also opened the door for looking at the possible influences on these proteins.
A few examples: for almost all receptors (keyholes on the cell membrane) one was able to find a hormone or neurotransmitter that specifically matched this receptor like a key fits the keyhole. But e.g for the receptor with the beautiful name peroxisome proliferator-activated receptor (PPAR) no specific hormone was found, so it was called an orphan receptor. Later it became clear that the PPAR could be activated by diet, and predominantly by free fatty acids as normal components of our daily nutrition.
But there are more examples: working in the world of sports and exercise we are interested in muscle growth and development. Most of us have heard of the hormonal influence on muscle growth like the effects of testosterone, growth hormone, insulin or cortisol. But other, probably even more important factors are myostatin, a protein that limits the growth of muscle tissue and mTOR and again a beautiful name here: Mammalian Target Of Rapamycin, which plays a dominant role in muscle growth.
A mutation or defect in the myostatin-gene can lead to exceptional muscle growth in dogs, cows and humans and one is looking for ways to block the effects of myostatin through pharmacological agents or through genetic manipulation.
mTOR is a direct target for our food again: the availability of amino acids, especially leucine, increases the activity of mTOR and increases protein synthesis.
Finally one started to unravel the directs effects of nutrients on the inner mechanisms of our cells, showing that nutrients work through the same basic principles and mechanism like hormones.
In the near future more research will show which specific food components trigger these specific metabolic and genomic effects.
This may lead to isolated, concentrated and combined nutrient packages, called nutraceuticals, which will have a great impact on health, functioning and performances. Natural food components might in some cases become alternatives for synthetic drugs.
Literature:
Bland, J.S: Genetic Nutritioneering; Keats Publishing, 1999.
Bucci, L: Nutrients as Ergogenic Aids for Sports and Exercise; CRC Press, 1993.
Wildman, R.C.(Ed.): Handbook of Nutraceuticals and Functional Foods, CRC Press, 2001.
Ryan, K.K; Seely, R.J: Food as a Hormone; Science; Vol.339, 2013, pg.918.
Liu, B; Qian, S.B: Translational regulation in nutrigenomics; Adv. Nutr.Vol.2, 2011, pg 511-519.
Brigelius-Flohé, R; Joost, H.G.(Eds.): Nutritional Genomics; Wiley, VCH, 2006.
Zempleni, J; Krishnamurti, K: (Eds.): Nutrients and Cell Signalling; Taylor & Francis , 2005.
Moustaid-Moussa, N: Berdanier, C.(Eds.): Nutrient-Gene Interactions in Health and Disease; CRC Press, 2001.
Mine, Y; Miyashita, K; Shahidi, F.(Eds.): Nutrigenomics and Proteomics in Health and Disease. Food Factors and Gene Interactions; Wiley-Blackwell, 2009.
