Cationic nanoparticles disrupt cellular signaling in a cholesterol dependent manner

Cationic beta-lactoglobulin nanoparticles as a bioavailability enhancer: Effect of surface properties and size on the transport and delivery in vitro

BLG (beta-lactoglobulin) and CBLG (cationic BLG developed by our lab) were evaluated as potential nutraceutical/drug carriers. The cationic corona conferred CBLG with superior integrity and drug retention under gastrointestinal conditions, at most 40-fold higher mucoadhesion, up to 30-fold greater transepithelial permeation and, at most 285% higher cellular uptake, compared to BLG. Furthermore, the more hydrophilic CBLG species exhibited better mucoadhesion, while the more hydrophobic one exhibited higher cellular uptake. Intriguingly, protein molecules were more cytotoxic and exhibited up to 175% higher tight junction-opening capacity than did protein nanoparticles, whereas the nanoparticles displayed up to 770% higher mucoadhesion, greater transepithelial permeation and elevated cellular uptake. Finally, all these surface properties and performances were significantly altered as CBLG bound to serum proteins. Possible mechanisms underlying these findings are discussed in detail. This research sheds some light on the development of protein-based nanoencapsulants and their performance upon oral administration.

Egg yolks inhibit activation of NF-κB and expression of its target genes in adipocytes after partial delipidation

How composition of egg yolk (EY) influences NF-κB, a key transcription pathway in inflammation, remains unclear. We performed partial delipidation of EY that removed 20-30% of cholesterol and triglycerides. The resulting polar and nonpolar fractions were termed EY-P and EY-NP. NF-κB activation in response to EY from different suppliers and their fractions was examined in 3T3-L1 adipocytes using a NF-κB response element reporter assay and by analyzing expression of 248 inflammatory genes. Although EY-P and EY contained similar level of vitamins, carotenoids, and fatty acids, only delipidated EY-P fraction suppressed NF-κB via down-regulation of toll like receptor-2 and up-regulation of inhibitory toll interacting protein (Tollip) and lymphocyte antigen 96 (Ly96). Our data suggest that anti-inflammatory activity of lutein and retinol were blunted by nonpolar lipids in EY, likely via crosstalk between SREBP and NF-κB pathways in adipocytes. Thus, moderate delipidation may improve the beneficial properties of regular eggs.