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Topical drug application is less prone to severe systemic side-effects than systemic application. Starting with the liposomes, various types of nanosized and microsized drug carriers have been developed to increase the notoriously low penetration of active agents into the skin, which limits not only the topical therapy of skin disease but also transdermal therapy. Today, liposome- and microsponge-based preparations are approved for dermatomycosis, acne and actinic keratosis. Under investigation are drug carriers such as lipid nanoparticles, polymeric particles, dendrimers, and dendritic-core multi-shell nanotransporters. According to the rapidly increasing research in this field, both in academia and industry, a breakthrough appears likely, once stability problems (nanoparticles) and safety concerns (dendrimers) are overcome. Technical approaches and results of in vitro, ex vivo and in vivo testing are described, taking into account pharmacokinetic, efficacy and safety aspects. [ABSTRACT FROM AUTHOR]

One of the strategies to reduce the side effects of platinum anticancer drugs is encapsulation of the drug in a lipid formulation. Nanocapsules represent a novel lipid-based drug delivery system, with high encapsulation efficiencies of cisplatin and carboplatin. The encapsulation in nanocapsules, dramatically improves the in vitro cytotoxicity of the platinum drugs towards carcinoma cell lines. The nanocapsule technology may generally be applicable to platinum drugs with limited water solubility and low lipophilicity, and improve the therapeutic index and profile of these drugs. [ABSTRACT FROM AUTHOR]

The antioxidant activities of brown algal phlorotannins were evaluated using the inhibition of phospholipid peroxidation in the liposome system, and by determining radical scavenging activities against the superoxide anion and 1,1-diphenyl-2-picrylhydrazyl (DPPH). Oligomers of phloroglucinol (1,3,5-trihydroxybenzene), eckol (a trimer), phlorofucofuroeckol A (a pentamer), dieckol and 8,8'-bieckol (hexamers), isolated from the Laminarian brown algae Eisenia bicyclis, Ecklonia cava and Ecklonia kurome, showed potent inhibition of phospholipid peroxidation at 1 μM in the liposome system. The phlorotannins had significant radical scavenging activities against the superoxide anion (50% effective concentration values: 6.5–8.4 μM) and DPPH (50% effective concentration values: 12–26 μM), and were more effective compared to ascorbic acid and α-tocopherol. For the purpose of using phlorotannins as functional food ingredients, the antioxidant activity of a complex of crude phlorotannins and soybean protein was examined. The complex had a pronounced DPPH-radical scavenging activity. These results suggest that phlorotannins are potent anti-inflammatory substances, and that the Laminariaceous brown algae, which are abundant in phlorotannins, may be useful as a new functional foodstuff or supplement with anti-inflammatory activity. [ABSTRACT FROM AUTHOR]

The blood brain barrier (BBB) is one of the most challenging barriers for drug delivery in the body. It significantly restricts the entry of low molecular weight compounds and biomacromolecules to the brain from the periphery. Inefficient delivery of the drugs, DNA and proteins to the brain is a major bottleneck in development of more efficacious and safe modalities for diagnostics and treatment of neurological diseases, especially at early stages of the disease when the BBB remains intact. The low permeability of the BBB is attributed, in large part, to the brain microvessel endothelial cells (BMVEC), which form tight extracellular junctions and have low pinocytic activity (Mayhan, 2001; Pardridge, 2005a). Some relatively lipophilic and low molecular weight substances can transport across the BMVEC by passive diffusion. However, a large number of lipophilic compounds are rapidly effluxed from the brain into the blood by extremely effective drug efflux systems expressed in the BBB (Begley, 1996; Fromm, 2000; Tamai and Tsuji, 2000; Loscher and Potschka, 2005a). These efflux systems include P-glycoprotein (Pgp), Multidrug Resistance Proteins (MRPs), breast cancer resistance protein (BCRP), and the multi-specific organic anion transporter (MOAT). There is also an enzymatic barrier to drug transport in the BMVEC. Activity of many enzymes that participate in the metabolism and inactivation of endogenous compounds, such as ν-glutamyl transpeptidase, alkaline phosphatase, and aromatic acid decarboxylase is elevated in cerebral microvessels (Minn et al., 1991; Abbott and Romero, 1996). These features of the BBB require discovery of new modalities allowing for effective drug delivery to the central nervous system (CNS), which is of great need and importance for treatment of neurodegenerative disorders. [ABSTRACT FROM AUTHOR]