Molecular Motions and Interactions in Aqueous Solutions of Thymosin-β4 , Stabilin C-Terminal Domain (CTD) and Their 1:1 Complex Studied by 1 H NMR Spectroscopy

Thymosin β4: A Multi-Faceted Tissue Repair Stimulating Protein in Heart Injury

Thymosin Beta-4 (Tβ4) is known as a major pleiotropic actin-sequestering protein that is involved in tumorigenesis. Tβ4 is a water-soluble protein that has different promising clinical applications in the remodeling and ulcerated tissues repair following myocardial infarction, stroke, plasticity and neurovascular remodeling of the Peripheral Nervous System (PNS) and the Central Nervous System (CNS). On the other hand, similar effects have been observed for Tβ4 in other kinds of tissues, including cardiac muscle tissue. In recent reports, as it activates resident epicardial progenitor cells and modulates inflammatory-caused injuries, Tβ4 has been suggested as a promoter of the survival of cardiomyocytes. Furthermore, Tβ4 may act in skeletal muscle and different organs in association/synergism with numerous other tissue repair stimulating factors, including melatonin and C-fiber-derived peptides. For these reasons, the present review highlights the promising role of Tβ4 in cardiac healing.

WT and A53T α-Synuclein Systems: Melting Diagram and Its New Interpretation

The potential barriers governing the motions of α-synuclein (αS) variants' hydration water, especially energetics of them, is in the focus of the work. The thermodynamical approach yielded essential information about distributions and heights of the potential barriers. The proteins' structural disorder was measured by ratios of heterogeneous water-binding interfaces. They showed the αS monomers, oligomers and amyloids to possess secondary structural elements, although monomers are intrinsically disordered. Despite their disordered nature, monomers have 33% secondary structure, and therefore they are more compact than a random coil. At the lowest potential barriers with mobile hydration water, monomers are already functional, a monolayer of mobile hydration water is surrounding them. Monomers realize all possible hydrogen bonds with the solvent water. αS oligomers and amyloids have half of the mobile hydration water amount than monomers because aggregation involves less mobile hydration. The solvent-accessible surface of the oligomers is ordered or homogenous in its interactions with water to 66%. As a contrast, αS amyloids are disordered or heterogeneous to 75% of their solvent accessible surface and both wild type and A53T amyloids show identical, low-level hydration. Mobile water molecules in the first hydration shell of amyloids are the weakest bound compared to other forms.