Application of Zymographic Methods to Study Matrix Enzymes Following Traumatic Brain Injury

Assays for proteolytic activity are often used to confirm a functional role for enzymes involved with CNS pathobiology. In studies focused on matrix metalloproteinases (MMPs), specifically those investigating the role of gelatinases (MMP-2, MMP-9), gelatin zymography is used to assess relative changes in enzyme activity. The advantages of this method lie in its gel separation of pro and active enzyme and the option for generation of semiquantitative data. Gelatin zymography is applied with success in studies of traumatic brain injury (TBI), but may require modifications for best results. In this chapter, we first present an overview of different zymographic approaches taken to assess the role of gelatinases in various forms of TBI and related CNS pathologies. Next, we focus on the specific method developed in our laboratory to optimize zymographic signal from injured CNS tissue. Finally, we include points of technique modification which have worked well for us, emphasizing tissue dissection, extraction method, and gel incubation period. This information is presented to offer support for those seeking to apply gelatin zymography with samples from injured brain tissue, where pathology can vary considerably. Individual models and experimental design may require further zymographic modifications for optimization of MMP detection.