Cationized albumin

Because of the presence of anionic sites on the endothelium and on the glycocalyx layer, anionic macromolecules show a significantly slower rate of extravasation compared with neutral and cationic macromolecules. Kern and Swanson [39] found a threefold increase in the permeability of the pulmonary vascular system to cationic albumin, compared with native albumin of the same molecular weight and hydrodynamic radius. 

Thole M, Nobmann S, Huwyler J, Bartmann A, Fricker G (2002) Uptake of cationized albumin-coupled liposomes by cultured porcine brain... 

Initial studies of brain delivery based on the chimeric peptide strategy used the absorptive-mediated uptake of cationized albumin which was chemically coupled to the opioid peptide P-endorphin [80] or its metabohcaUy stabilized analogue [D-Ala ]P-endorphin. Tracer experiments in which the chimeric peptide was labelled in the endorphin moiety provided evidence of internalization by isolated brain capillaries and transport into brain tissue in vivo [81]. 

It has been reported that the plasmid vector is unable to translocate to the nucleus unless complexed in the cytoplasm with nuclear proteins possessing NLS. NLS are short karyophilic peptides on proteins that bind to specific transporter molecules in the cytoplasm, mediating their passage through the pore complexes to the nucleus. Examples of these peptides will be given later in this section. DNA can also be presented to cells in culture as a complex with polycations such as polylysine, or basic proteins such as protamine, total histones or specific histone fractions (110), cationized albumin, and others. These molecules increase the transfection efficiency. In addition histone HI is identified as transfection-enhancing protein in cell culture (111). 

Cationized proteins + Cationized albumin AMT Blood to brain [49]... 

Kumagai AK, Eisenberg IB, Pardridge WM (1987) Absoiptive-mediated endocytosis of cationized albumin and a beta-endoiphin-cationized albumin clrimeiic peptide by isolated brain capillaries. Model system of blood-brain barrier transport. J Biol Chem 262 15214—15219. 

Vorbrodt AW, Trowbridge RS (1991) Ultrastructural study of transcellular transport of native and cationized albumin in cultured sheep brain microvascular endothelium. 1 Neurocytol 20 998-1006. 

Lu W, Sun Q, Wan J, et al. Cationic albumin-conjugated pegylated nanoparticles allow gene delivery into brain tumors via intravenous administration. Cancer Res 2006 66 11878-11887. 

Ritz S, Eisele K, Dom J et al (2010) Cationized albumin-biocoatings for the immobilization of lipid vesicles. Biointerphases 5 PA78-FA87. doi 10.1116/1.3494039... 

However a quaternary ammonium palmitoyl glycol chitosan nanomedicine with a particle size of 150 nm, on intravenous delivery, is able to enhance the brain activity of the anaesthetic propofol by ten-fold (Fig. 11.10). Although a reduced particle size is integral to the activity of this nanomedicine, as a particle size in excess of 400 nm does not yield the bioavailability gains seen with the smaller particle size, its mechanism of action is not entirely clear. Cationic albumin particles, for example have been reported to cross the blood brain barrier and it may be that these chitosan amphiphiles, by virtue of their cationic nature, are also capable of transporting materials across the blood brain barrier. 

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