Review · PMID 41742019

The Tβ4-Ac-SDKP Axis in Kidney Disease: Renoprotective Efficacy Review — VialBase Research

Tβ4 and its metabolite Ac-SDKP act as dynamic mediators of renal injury and repair

Last updated · 2026 · Various · Renal Review
Key findings
  • Tβ4 and its metabolite Ac-SDKP act as dynamic mediators of renal injury and repair
  • Ac-SDKP inhibits TGF-β1/Smad signaling, reducing fibrosis
  • Cytoprotective, anti-inflammatory, and antifibrotic actions demonstrated across models of acute and chronic kidney injury
  • Tβ4 is encoded by the X-linked TMSB4X gene and is the predominant β-thymosin in mammalian cells

Summary

Comprehensive review synthesizing current evidence on the Thymosin β4 (Tβ4) and its N-terminal metabolite N-acetyl-Ser-Asp-Lys-Pro (Ac-SDKP) axis in kidney disease. Maps intracellular and extracellular mechanisms, relevant signaling pathways, and cell-type-specific expression across glomerular and tubular compartments. Critically evaluates renoprotective efficacy including cytoprotection, anti-inflammatory, and antifibrotic actions across models of acute and chronic kidney injury.

Key Findings

  • Tβ4 was once considered mainly an actin-sequestering molecule but now emerges as a multifunctional regulator of cellular homeostasis
  • Ac-SDKP (derived from Tβ4 N-terminal cleavage) is itself a potent antifibrotic agent acting via TGF-β1/Smad pathway inhibition
  • Demonstrated renoprotective effects in both acute kidney injury (AKI) and chronic kidney disease (CKD) models
  • Spatial expression mapping shows differential expression across glomerular and tubular compartments

Relevance to TB-500

Expands the therapeutic narrative for TB-500/Tβ4 beyond musculoskeletal healing into renal protection. The Tβ4-Ac-SDKP axis represents a distinct mechanism (antifibrotic) from the more commonly discussed wound healing and angiogenesis pathways. Suggests potential applications in kidney disease, adding to TB-500’s profile as a systemic healing peptide.

Citation

PMID: 41742019

See Also