Electrospun PLLA nanofiber scaffolds and their use in combination with BMP-2 for reconstruction of bone defects.

Introduction: Adequate migration and differentiation of mesenchymal stem cells is essential for regeneration of large bone defects. To achieve this, modern graft materials are becoming increasingly important. Among them, electrospun nanofiber scaffolds are a promising approach, because of their high physical porosity and potential to mimic the extracellular matrix (ECM).

Synthesis and biological testing of novel pyridoisothiazolones as histone acetyltransferase inhibitors.

We present a combination of database screening, synthesis and in vitro testing to identify novel histone acetyltransferase (HAT) inhibitors. The National Cancer Institute compound collection (NCI) and several commercial databases were filtered by similarity-based virtual screening to find new HAT inhibitors. Employing the recombinant HAT p300/CBP-associated factor (PCAF) and two different histone substrates for screening, pyridoisothiazolones were identified as inhibitors of human PCAF.

Pyridylalanine-containing hydroxamic acids as selective HDAC6 inhibitors.

We synthesized hydroxamic acids with a pyridylalanine substructure and identified them as selective inhibitors of human recombinant HDAC6. The in vitro selectivity was up to 25-fold for HDAC6 over HDAC1 and was confirmed by Western blotting to assess tubulin versus histone acetylation in cancer cells. Docking studies with an HDAC6 homology model suggested that the hydrophobic cap group of the inhibitors interacts with aromatic residues that form a sub-pocket near the entrance of the substrate binding channel.

Phenylalanine-containing hydroxamic acids as selective inhibitors of class IIb histone deacetylases (HDACs).

We synthesized biarylalanine-containing hydroxamic acids and tested them on immunoprecipitated HDAC1 and HDAC6 and show a subtype selectivity for HDAC6 that was confirmed in cells by Western blot (tubulin vs histones). We obtained an X-ray structure with a HDAC6-selective inhibitor with the bacterial deacetylase HDAH. Docking studies were carried out using HDAC1 and HDAC6 protein models.