The Fly Diet

It's well known that a woman's diet can affect her baby. But ongoing research by Daniela Drummond-Barbosa, PhD, suggests that diet might determine whether she can produce one in the first place.

For the past decade, Drummond-Barbosa, an associate professor of Biochemistry and Molecular Biology, has explored how diet regulates ovarian cells in Drosophila melanogaster, the common fruit fly. By manipulating Drosophila's genes, Drummond-Barbosa and her colleagues have identified several nutrient-sensitive pathways that influence the ovarian stem cells that make egg production possible. (Adult humans appear to lack ovarian stem cells, but our embryonic germ cells play a similar role in utero, eventually developing into eggs.) They've also demonstrated that the same pathways affect the ovarian microenvironment. That microenvironment, or "niche," sustains the stem cells, as well as their daughter cells (specific cell types they produce through division, which go on to form eggs). For example, Drummond-Barbosa discovered that insulin levels-increased by carbohydrate intake-influence the rate at which ovarian stem cells proliferate, while diet-related changes to the ovarian niche affect the numbers that are maintained.

But in a complex living organism, many different organs and tissues will respond to the nutrients they encounter, and any of those responses could conceivably affect the ovaries and their contents. As a result, Drummond-Barbosa recently decided to explore how diet-driven signals from fat cells, which play an important role in regulating appetite, metabolism and insulin sensitivity throughout the body, might influence ovarian stem cells and their environment. In a series of as-yet-unpublished experiments, Drummond-Barbosa and postdoctoral fellow Alissa Armstrong, PhD, found that the presence of diet-related substances such as insulin and amino acids causes fat cells to release biochemical signals that trigger "really specific effects" in ovarian stem cells, their niches and their daughter cells.

If further research reveals that the relationships between fat cells and ovarian stem cells in Drosophila also apply to human embryonic germ cells, Drummond-Barbosa's work could shed new light on how diet affects the early stages of ovarian cell development in people-and, hence, their ability to produce offspring. Additionally, clarifying how fat cells and stem cells interact could help explain the link between obesity and various diseases, including cancer.