Marek Ma, M.D.
Instructor A, Emergency Medicine
Dr. Ma's laboratory is interested in understanding the role of calpains in axonal injury by using a rat optic nerve stretch model that simulates the mechanics of DAI in humans. Calpains are a family of Ca2+-dependent cytosolic proteases involved in cytoskeletal remodeling, cell-cycle regulation, signal transduction, cell differentiation, embryonic development, vesicular trafficking, and apoptosis and necrosis. There are two ubiquitous isoforms, µ-calpain and m-calpain, which differ in the Ca2+ concentration required for activity. Calpain activity has been detected within 15 minutes of DAI in animal models. A causal role for pathologic calpain activity after axonal injury is supported by calpain inhibitor studies, which demonstrate an attenuated disruption of axonal transport. The lab seeks to better understand the downstream consequences of early calpain activation after traumatic axonal injury.
Hospital of the University of Pennsylvania's Department of Emergency Medicine
Email address: MaMarek@uphs.upenn.edu