Back in the 1930s, scientists noticed that water fleas and rats fed restricted diets while young went on to live longer. The same effect has since turned up in fruit flies and mice. What we did not know was how a meal eaten in infancy could affect health weeks, months, or even years later.
A recent Nature study might have found the answer. A team led by Fumiaki Obata, a biologist at the RIKEN Center for Biosystems Dynamics Research in Kobe, Japan, found a protein that carries a record into adulthood of what fruit flies ate as larvae, influencing how long they live. Lab fruit flies are fed a mix of yeast and sugar, with yeast being their main source of protein.
This low-protein diet was introduced roughly halfway through the larval period. Once the flies emerged from their pupae as adults, they went back on standard food. In Obata’s experiment, the protein-restricted flies, males and females alike, outlived their well-fed siblings.
The flies were paler and lighter, weighing sometimes 28 percent less. The females also laid fewer eggs. Reproduction and lifespan are always in a tradeoff relationship,” Obata says.
They have fewer eggs and they are slightly smaller. But they have a lifespan extension.” This typical tradeoff wasn’t the whole story, though. When the team added amino acids, the building blocks of proteins, back into the low-yeast larval food, the lifespan boost disappeared.
Somehow, the adult flies’ bodies were remembering how much protein they had eaten as larvae. Obata and his colleagues called this a nutritional memory and set out to find where exactly in the body that memory was kept.
Extract — continue reading at the source.
