Do you like to have a sugary or cheesy diet? Surely you can answer this question as fast as a bullet shot!
Which one is a better choice for good health? Well, your forehead wrinkles say that you are thinking about the answer. Isn’t it?
A similar thought process intrigued scientists Brenda K. Richards and Jacob Simon from Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA.
This group of scientists wanted to understand the intrinsic processes of food choice. They also attempted to investigate how to ensure that those choices are healthy.
Information from this kind of research would help fight global epidemics like obesity, diabetes, and cardiovascular diseases.
The choice of carbohydrate- versus fat-rich foods is a complex feature that depends on genetic and environmental factors. During the 2000s, Brenda K. Richards’ group attempted to find specific genes responsible for such choice preference using a mouse model.
Why Did The Scientists Choose Mice For Experimenting?
Mice are excellent models for genetic mapping and follow-up studies. The reason is:
Mice and humans share approximately 70 % of
the same protein-coding genes
Like humans, mice prefer to eat more carbohydrates than fat when selecting food choices. In previous experiments, the same group of scientists discovered a specific region on mouse chromosome 17 named Mnic1 (macronutrient intake-carbohydrate). They experimentally confirmed that this region contains a gene or genes responsible for carbohydrate preference.
Why Did They Choose Saliva As The Sample?
Saliva has a primary role in food processing in the mouth. It starts the process of digestion. Saliva may also modulate taste stimuli by solubilizing and transporting taste molecules. Thus, saliva can influence diet choice by affecting the perception of texture or flavour.
Saliva contains electrolytes and more than 1000 different proteins that might influence food intake or food choice. On the other hand, the secretion or binding activities of salivary proteins may get modified by diet composition.
Because of the implications of these relationships for oral health, nutrition, and commercial applications, it was important to understand the interaction of genetic and dietary factors in the expression of salivary proteins.
How Did They Plan Their Experiment?
Brenda K. Richards’ research group planned the study with two groups of mice – a) a Control group or wild-type and b) a genetically modified group.
Experimental diet mixes were given. The mice were assessed by a choice between fat-protein and carbohydrate-protein diet mixtures.
They planned to study the following:
- Effects of diet and genotype on salivary hyaluronic acid levels
- Effects of diet and genotype on gene expression in salivary glands
To identify potential candidate genes for carbohydrate-rich or fat-rich food choices, they examined known genes located within the Mnic1 region.
What Were The Findings And Conclusion?
The study revealed interesting facts! Many genes that were present in the Mnic1 region were also being expressed in the salivary glands as follows:
- Dcpp2 (demilune cell and parotid protein 2)
- Prrt1 (proline-rich transmembrane protein 1), and
- Has1 (hyaluronan synthase 1)
Mnic1 region contains genes that influence
The results indicated a positive correlation between salivary hyaluronic acid (HA) levels and proportional fat intake, regardless of genotype.
In summary, this study demonstrated that the expression levels of salivary proteins Dcpp2, Prrt1 Has1 and salivary HA may be good indicators to determine food choice preferences.
What Is The Importance Of Such Studies In The Present Day?
This type of information extended to humans might give valuable insights into high-fat or carbohydrate-rich food preferences. Simple salivary tests can be validated and performed commercially for individuals with a higher risk of obesity, diabetes and cardiovascular diseases. It will help initiate lifestyle modification programs among these risk groups and reduce the disease burden.