Potential health effects of brewers' spent grain as a functional food ingredient assessed by markers of oxidative stress and inflammation following gastro-intestinal digestion and in a cell model of the small intestine

Brewer's spent grains (BSG) are a by-product of the beer-brewing industry, often employed as animal feeding stuffs. With BSG being rich not only in proteins, lipids, and dietary fiber but also in certain phytochemicals, it constitutes a potentially valuable food source that could be employed as a functional food, e.g. against chronic inflammatory diseases. Several types of bread were prepared with various amounts of BSG as flour replacement (0, 10, 20, 40, 60, 80 and 100%), either employing wet BSG or dried BSG after pressing. Total phenolics, flavonoids, insoluble dietary fiber, as well as antioxidant capacity (FRAP, ABTS) were measured in the bread, before and after simulated gastro-intestinal digestion. Furthermore, we investigated digested BSG and bread-containing BSG for their capability to alter oxidative stress (Nrf2, malondialdehyde) and inflammation (IL-6, IL-8, NO, and PGE2) in a Caco-2 cell culture model of the small intestine. Incorporation of BSG significantly and dose-dependently enhanced the amount of dietary fiber in the product, as well as total phenolics, flavonoids, and antioxidant capacity, by over 10-fold, 3-fold, 4-fold and 5-fold, respectively, when replacing all of the flour with BSG. This pattern remained after in vitro digestion. However, digesta failed to show significant antioxidant or anti-inflammatory effects on the biomarkers observed in the cell model. Consuming 150 g of such a BSG-bread (wet based) would supply the proposed RDA of 25 g d^-1 dietary fiber and could be a healthy product valorizing BSG.

Core cross-linked micelles of polyphosphoester containing amphiphilic block copolymers as drug nanocarriers

Poly(ethylene oxide)-b-polyphosphoester bearing unsaturations are promising materials for drug delivery applications.

In vitro investigations of smart drug delivery systems based on redox-sensitive cross-linked micelles

Redox-sensitive micelles are designed by using block copolymers of different architectures composed of a hydrophilic block of poly(ethylene oxide), and hydrophobic blocks of poly(ϵ-caprolactone) and poly(α-azide-ϵ-caprolactone). Stability of these micelles is insured in diluted media by cross-linking their core via the addition of a bifunctional cross-linker, while redox sensitivity is provided to these micelles by inserting a disulfide bridge in the cross-linker. The potential of these responsive micelles to be used as nanocarriers is studied in terms of cytotoxicity and cellular internalization. The release profiles are also investigated by varying the environment reductive strength.

Smart nanocarriers for pH-triggered targeting and release of hydrophobic drugs

The use of hybrid pH-sensitive micelles based mainly on the (PEO)(129)(P2VP)(43)(PCL)(17) ABC miktoarm star copolymer as potential triggered drug delivery systems was investigated. Co-micellization of this star copolymer with a second copolymer labeled by a targeting ligand, i.e. biotin, on the pH sensitive block (poly-2-vinylpyridine) is considered here in order to impart possible active targeting of the tumor cells. Two architectures were studied for these labeled copolymers, i.e. a miktoarm star or a linear ABC terpolymer, and the respective hybrid micelles are compared in terms of cytotoxicity (cells viability) and cellular uptake (using fluorescent dye loaded micelles). Finally, the triggered drug release in the cytosol of tumor cells was investigated by studying, on the one hand, the lysosomal integrity after internalization and, on the other hand, the release profile in function of the pH.