Search

The global diffusion of benign prostatic hyperplasia (BPH) demands the search for safe and effective treatment alternatives to the drugs commonly used, which exert both side and adverse effects. Among plant-based products, the extracts of Epilobium angustifolium L. (EAEs) could improve BPH symptoms thanks to the presence of ellagitannins and their anti-inflammatory metabolites, urolithins. This study focused its attention on a commercial EAE, standardized to contain ≥ 15 % oenothein B, to determine a) the metabolic profile and the chemical degradation induced by digestion, b) in vivo bioavailability after acute and prolonged treatments of CD1 mice, and c) in vitro antioxidant activity. Utilizing RP-HPLC-PDA-ESI-MSn analysis, 20 different compounds were identified. Polyphenols suffered from degradation after both orogastric and duodenal digestion processes, suggesting that gastro-resistant coating agents are required to preserve the bioactive components occurring in the EAE phytocomplex from orogastric digestion. In vivo data underlined the presence of urolithins only after the prolonged treatment, confirming that the gut fermentation process requires at least 24 h to produce urolithins. Finally, an increase of Superoxide Dismutase-1 (SOD-1), which represents one of the fundamental endogenous antioxidant defenses, was determined in an EAE pretreated LNCap cell model system, confirming EAE antioxidant activity.

Oligosaccharides aberrantly expressed on tumor cells influence processes such as cell adhesion and modulation of the cell’s microenvironment resulting in an increased malignancy. Schmidt’s imidate strategy offers an effective method to synthesize libraries of various oligosaccharide mimetics. With the aim to perturb interactions of tumor cells with extracellular matrix proteins and host cells, molecules with 3,4-bis(hydroxymethyl)furan as core structure were synthesized and screened in biological assays for their abilities to interfere in cell adhesion and other steps of the metastatic cascade, such as tumor-induced angiogenesis.The most active compound, (4-{[(β-D-galactopyranosyl)oxy]methyl}furan-3-yl)methyl hydrogen sulfate (GSF), inhibited the activation of matrix-metalloproteinase-2 (MMP-2) as well as migration of the human melanoma cells of the lines WM-115 and WM-266-4 in a two-dimensional migration assay. GSF inhibited completely the adhesion of WM-115 cells to the extracellular matrix (ECM) proteins, fibrinogen and fibronectin.In an in vitro angiogenesis assay with human endothelial cells, GSF very effectively inhibited endothelial tubule formation and sprouting of blood vessels, as well as the adhesion of endothelial cells to ECM proteins. GSF was not cytotoxic at biologically active concentrations; neither were 3,4-bis{[(β-D-galactopyranosyl)oxy]methyl}furan (BGF) nor methyl β-D-galactopyranoside nor 3,4-bis(hydroxymethyl)furan, which were used as controls, eliciting comparable biological activity. In silico modeling experiments, in which binding of GSF to the extracellular domain of the integrin αvβ3 was determined, revealed specific docking of GSF to the same binding site as the natural peptidic ligands of this integrin. The sulfate in the molecule coordinated with one manganese ion in the binding site.These studies show that this chemically easily accessible molecule GSF, synthesized in three steps from 3,4-bis(hydroxymethyl)furan and benzoylated galactose imidate, is nontoxic and antagonizes cell physiological processes in vitro that are important for the dissemination and growth of tumor cells in vivo.

Density functional theory (DFT) computations at the B3LYP/Lanl2DZ level were used to elucidate the oxygen atom transfer (OAT) and coupled electron proton transfer (CEPT) reaction steps involved in the biomimetic catalytic cycle performed by polymer-supported Mo VIO2(NN')(2) complexes [NN'=phenyl-(pyrrolato-2-ylmethylene)-amine] with water as oxygen source, trimethyl-phosphane as oxygen acceptor and one-electron oxidising agents. The DFT method employed has been validated against experimental data [X-ray crystal structures of a NN' ligand and a Mo VIO2(NN')2 complex as well as kinetic data]. The rate-limiting step in the forward-OAT from [Mo VIO2] to PMe3 is the attack of PMe3 at an oxo ligand with DeltaG not equal (298 K)=64.6 kJ mol(-1). Dissociation of the product OPMe3 is facile with DeltaG( not equal) (298 K)=26.3 kJ mol(-1) giving a mono-oxo [Mo IVO] complex which fills its coordination sphere with a further PMe3 substrate with DeltaG not equal (298 K)=39.2 kJ mol(-1). One-electron oxidation to a Mo(V) phosphane complex precedes the coordination of water/hydroxide. Additionally, the comproportionation of [Mo VIO(2)] and [Mo IVO] to dinuclear oxo-bridged [O=MoV-O-MoV=O] species has been calculated as the thermodynamic sink in this system and the back-OAT from dmso to mono-oxo [Mo IVO] to give [Mo VIO2] has been shown to involve an equilibrium between stereoisomeric [Mo VIO2] complexes with an activation barrier of DeltaG not equal (298 K)=113.1 kJ mol(-1).