AMES, Iowa — Flies have very few redeeming qualities. They’re dirty, loud, and often seem to strategically annoy any human they encounter. Remarkably, these irritating bugs may just help modern science discover the fountain of youth when it comes to heart health.
Researchers at Iowa State University believe they may have uncovered a way to reverse the aging process in fruit flies’ heart muscles. This discovery could conceivably lead to the development of new treatments for older people dealing with heart disease.
The study investigated the genetic mechanism that causes fruit flies’ cardiac muscles to grow weak and deteriorate over time. During the course of research, scientists were actually able to restore a large portion of cardiac function in middle-aged flies. Believe it or not, older flies usually deal with heart problems that mirror the cardiac difficulties seen in human aging.
The study’s authors’ approach began by examining the flies’ autophagy, or cellular “cleanup process” that vanquishes and recycles weakened proteins and organelles. Autophagy naturally slows down with age, which consequently leads to weakened muscles that aren’t able to recover.
Next, they looked into a key genetic pathway seen in virtually all living things that balances a being’s growth with its nutrient intake. This pathway, called mechanistic target of rapamycin (mTOR), is also related to autophagy and the overall aging process. One of the two complexes that underlie the mTOR pathway, mTORC2, tends to decrease with age as autophagy slows down. However, the research team discovered that by boosting mTORC2, they were able to reverse the aging process and strengthen the heart muscles of older fruit flies.
“Boosting the complex almost fully restored heart function,” comments Hua Bai, an assistant professor of genetics, development and cell biology at Iowa State University, in a university release.
While this discovery may seem trivial within the context of flies, it could have major implications when it comes to the treatment of heart disease in human patients. Humans’ and flies’ generally age in the same way, and by middle age, heart muscles in both flies and humans are much weaker than they were in the past.
“The fly model can be useful for developing drug target discoveries that could have a big impact on human health,” Bai comments.
Researchers analyzed thousands of video recordings of fruit flies’ cardiac muscles at different ages. These observations showed that boosting mTORC2 could improve a five to six week old fly’s heart function to where it was when the fly was only one to two weeks old. Obviously flies have much shorter lifespans than humans, so that would equate to improving a middle aged adult’s heart function to its strength during young adulthood.
The study is published in Autophagy.