Cardioprotective Potential of Exogenous Ubiquitin.

Ischemic heart disease (IHD) accounts for the majority of heart disease-related deaths worldwide. Ubiquitin (UB), found in all eukaryotic cells, is a highly conserved low molecular weight (~8.5 kDa) protein. A well-known intracellular function of UB is to regulate protein turnover via the UB-proteasome system. UB is a normal constituent of plasma, and elevated levels of UB are observed in the serum of patients under a variety of pathological conditions. Recent studies provide evidence for cardioprotective potential of exogenous UB in the remodeling process of the heart in IHD, including effects on cardiac myocyte apoptosis, inflammatory response, and reorganization of the vasculature and extracellular matrix. This review summarizes functions of UB with an emphasis on the role of exogenous UB in myocardial remodeling in IHD.