The difference physiological reactions to candy eating, for different age groups, comes down to genetics, according to new research. Specifically a gene termed Foxo may be responsible. This association comes from studies on fruit flies.
The study has pinpointed a mechanism that enables fruit flies to adapt to changes introduced into their diet when they are young. This same adaptive mechanism seems to become mis-regulated as the flies become older. The effect of this is to disrupt metabolic homeostasis (the internal balance within the body).
To show this, researchers looked at the regulation of Foxo genes in the intestines of fruit flies. The gene is found within the flies and in people fruit flies are commonly studied in order to provide answers about human genetics. This is because the fruit flies are easy to maintain; they also have many offspring; and they grow rapidly. In addition, fruit flies share with humans several “master,” or homeotic, genes. By studying the formation of genes in a fly, this provides useful information about what may be happening in people.
The Foxo gene is expressed throughout the body, found in muscle, the liver and pancreas. In particular it regulates aspects of metabolism in response to insulin signaling. In younger animals, when they are exposed to dietary changes, insulin signaling becomes repressed and the Foxo gene is turned on.
However, as animals age, Foxo stops responding to insulin signalling. This causes disruption of lipid metabolism. This can cause age-related loss of metabolic balance and with it a range of inflammatory diseases.
The research has been published in the journal Cell Reports. The paper is titled “Misregulation of an adaptive metabolic response contributes to the age-related disruption of lipid homeostasis in Drosophila.”
