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Medlock Receives Grant from American Heart Association

AU/UGA Medical Partnership faculty member Amy Medlock recently received grant funding for a study addressing questions related to intercellular heme trafficking. The work is being funded by the American Heart Association Greater Southeastern Affilliate Grant-In-Aid program.  Heme is an important component of hemoglobin and is involved in oxygen transport and tissue delivery. In addition, heme is involved in many other critical processes including drug metabolism and energy production and has recently been shown to be a key regulator of metabolism, circadian rhythm and development.

The primary aim of the newly-funded work is to determine if heme can be transported between cells and utilized. While the current dogma in the field is that all heme that is moved between cells is sent to the liver for degradation, little evidence exists to support this idea. Several recent publications have led the Medlock laboratory to question this long-standing dogma. These studies suggest that heme transporters exist on the surface of many cell types and function in heme import and export and may be important in controlling the amount of free heme outside of cells.

To address the movement of heme between cells for utilization, the Medlock laboratory will use zebrafish as a model organism. By observing the growth and development of zebrafish which can only make heme in certain cells or zebrafish with a decreased amount of cell surface heme importer or exporter, a clear picture of the importance heme trafficking for utilization in people will emerge. A better understanding of if and how heme is transported between cells for utilization may translate to treatments that will protect cells from damage that occurs following a stroke as well as provide alternative treatments for anemias.

The AHA Greater Southeastern Affilliate Grant-In-Aid program reviewed 180 applications and funded 26 of these. The review panel stated “[Dr. Amy Medlock] is poised to test the dogma that every cell synthesizes heme, and the application has the potential to move the field forward in understanding how heme is synthesized and potentially transported between cell types.”