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Albany, NY – In today's Academic Minute, Dr. Alex Shingleton of Michigan State University reveals how the body protects its most important features during times of malnourishment.
Alex Shingleton is an assistant professor of zoology at Michigan State University where his research seeks to understand how the environment influences body and organ size. Shingleton works primarily with the fruit fly Drosophila and his work has been published in numerous scientific journals. He holds a Ph.D. from the University of Cambridge.
Dr. Alexander Shingleton - Malnutrition and Physical Development
People that have been malnourished during childhood typically end up as smaller adults, with shorter arms and legs, and smaller hearts and lungs. However, some key organs are able to protect themselves from the effects of a poor diet and grow to almost their full size. One important example is our brain, which is more or less the same size in both well-fed and poorly-fed individuals.
Researchers in my lab have been trying to answer a simple questions; why are some organs, like our brain, less sensitive to changes in nutrition than others? Rather than using humans or mammals to answer this question, we have been using fruit flies, which grow rapidly and are easier, and cheap, to maintain in the lab.
In fruit flies it is the male genitalia that are relatively insensitive to changes in nutrition, and we found that this is because of a very simple mechanism: In most organs, malnutrition causes them to apply a biochemical brake on their growth, similar to you applying a brake to your car to slow it down. This brake is a protein called FOXO, which is activated when an organ senses that it is being starved. The genitals do not, however, apply this brake - for the simple reason that they do not really have the brake. They only produce very small quantities of FOXO and so are able to keep growing even when nutrition is low.
Excitingly, FOXO is the same biochemical brake used by humans to suppress growth when they are malnourished, and we predict that differences in the production of FOXO in different organs controls their individual response to changes in diet. More generally, our research has shown how organs and tissues can control their sensitivity to environmental changes such as diet. Our environment has a huge impact on our development and physiology and many diseases result when our response to environmental change is either too extreme or too subtle. Understanding how we can modify this response is an important step in developing treatments to prevent or treat these diseases.