Thymosin b4 is a major actin sequestering peptide found in most mammalian cells. It is involved in cell migration, differentiation, proliferation and survival. In addition to its role in cell migration, it is also important in blood vessel formation.
Its functions in the cell are still not well understood. However, some reports suggest that TB4 may play a critical role in the development of cardiovascular organs. The peptide has also been shown to promote wound healing, particularly in corneal wounds.
Tb4 is produced locally by a subset of neurons, and it is widely distributed in mammalian tissues. Some studies have suggested that it is also released by damaged or dying cells.
In addition to its potential role in cell growth and migration, TB4 is also believed to have a protective effect on the brain. Studies have demonstrated that Tb4 increases cardiac function in chronic myocardial ischemia in pigs.
Thymosin b4 is also considered to be a potent regulator of actin polymerization in living cells. In particular, it inhibits the TGF-b pathway. Moreover, thymosin b4 inhibits apoptosis in a UUO rat model of ischemic acute kidney injury.
In addition, it has been shown to alleviate tubular cell apoptosis. Consequently, it has been suggested that TB4 could be a novel reparative factor in renal fibrosis.
Additionally, thymic peptides may represent a new class of potent wound healing agents. This is due to the fact that thymic peptides are a form of angiogenic factor, which can enhance wound repair.