Thymosin beta-4 (Tβ4) (Tβ4)

Thymosin beta-4 (Tβ4) is a 43-amino acid, highly conserved acidic peptide that serves as the primary G-actin sequestering molecule in most mammalian cells [1]. By maintaining a pool of unpolymerized actin, it plays a fundamental role in cytoskeletal dynamics, which are essential for cell motility, phagocytosis, and tissue morphogenesis [2]. Beyond its intracellular functions, Tβ4 is released into the extracellular environment following tissue injury, where it acts as a potent regenerative factor [3]. It promotes wound healing by stimulating the migration of epithelial cells, enhancing angiogenesis, and reducing inflammation through the inhibition of NF-κB signaling [3][4]. In clinical settings, Tβ4-derived peptides like Timbetasin are being evaluated for their ability to treat ocular surface diseases and promote cardiac repair after myocardial infarction [5]. While its regenerative properties are therapeutically promising, its role in enhancing cell migration and blood vessel growth necessitates careful monitoring regarding potential oncogenic risks [2].

Other names

TMSB4XThymosin β4Tbeta4Hematopoietic system regulatory peptideSeraspenide

Thymosin beta-4 acts as a G-actin sequestering peptide, regulating cytoskeletal dynamics by preventing actin polymerization [1][2]. It also functions as an extracellular signaling molecule that activates the PI3K/Akt pathway to promote cell migration and survival, while inhibiting NF-κB to reduce the production of pro-inflammatory cytokines [3][4]. Additionally, it promotes angiogenesis by increasing the expression of vascular endothelial growth factor (VEGF) [4].