Thioredoxin-Interacting Protein Controls Cardiac Hypertrophy Through Regulation of Thioredoxin Activity

Publisher Website
Google Scholar
Abstract
Background— Although cellular redox balance plays an important role in mechanically induced cardiac hypertrophy, the mechanisms of regulation are incompletely defined. Because thioredoxin is a major intracellular antioxidant and can also regulate redox-dependent transcription, we explored the role of thioredoxin activity in mechanically overloaded cardiomyocytes in vitro and in vivo. Methods and Results— Overexpression of thioredoxin induced protein synthesis in cardiomyocytes (127±5% of controls, P P P P P P P Conclusions— Thus, even though thioredoxin is an antioxidant, activation of thioredoxin participates in the development of pressure-overload cardiac hypertrophy, demonstrating the dual function of thioredoxin as both an antioxidant and a signaling protein. These results also support the emerging concept that the thioredoxin inhibitor Txnip is a critical regulator of biomechanical signaling.