Skin delivery of hydrophilic molecules from liposomes and polysaccharide-coated liposomes.

OBJECTIVES: Liposomes are commonly used in cosmetic formulations to increase the bioavailability of active ingredients. We have previously shown that polysaccharide coating of liposomes improves their resistance to surfactants and electrolytes. In the current study, we have assessed the impact of coating on the skin penetration enhancer properties of liposomes. METHODS: The physicochemical properties of coated liposomes (Ionosomes™) were evaluated before and after encapsulation of two different hydrophilic molecules (caffeine and a hexapeptide), and compared to those observed with non-coated liposomes. Moreover, in vitro permeation experiments were performed using Franz™-modified diffusion cells, with normal human skin as membranes. RESULTS: Results showed that both coated and non-coated liposomes significantly improved the bioavailability of hydrophilic active molecules in skin, compared to reference solutions. Although liposome coating slightly reduced entrapment efficiency, the delivery of active molecules was not adversely affected by the process. In conclusion, polysaccharide coating of liposomes allows for better protection of their integrity without compromising the skin bioavailability of the active molecules that they convoy.

Cytotoxic activity of methanol extracts from Basidiomycete mushrooms on murine cancer cell lines.

Crude methanol extracts of 58 mushroom species were screened for their cytotoxic activities against two murine cancer cell lines, L1210 and 3LL, using the tetrazolium assay. A majority of extracts (74%) exhibited IC50 > 100 microg/ml against both cell lines. A most marked activity against one of the cell lines was noted for nine species (14% of the tested species). While Amanitales and Russulales tested were not found active, Polyporales and Boletales gave better results. Four species exhibited a significant cytotoxic activity (IC50 < or = 20 microg/ml) against at least one of the two murine cancer cell lines (Ganoderma lucidum, Meripilus giganteus, Suillus granulatus, S. luteus). The last one had never been investigated for its cytotoxic compounds before.

Cytotoxic activity of some lichen extracts on murine and human cancer cell lines.

Eight lichens were extracted successively with n-hexane, diethyl ether and methanol using a Soxhlet process. The cytotoxic activity of the 24 lichen extracts was evaluated in vitro using two murine (the L1210: lymphocytic leukaemia, and the 3LL: Lewis lung carcinoma) and four human (the K-562: chronic myelogenous leukaemia, the U251: glioblastoma, the DU145: prostate carcinoma, and the MCF7: breast adenocarcinoma) cancer cell lines and non-cancerous cells, the Vero cell line (African green monkey kidney cell line). The MTT assay revealed significant cytotoxicity (IC50 < or = 20 microg/ml) on one of the tested cancer cell lines for at least one extract of each lichen species. Some extracts of Cladonia convoluta, Cladonia rangiformis, Parmelia caperata, Platismatia glauca and Ramalina cuspidata demonstrated interesting activities particularly on human cancer cell lines as good selectivity indices were recorded (SI > 3).

Antiviral and cytotoxic activities of some Indonesian plants.

Ten methanolic extracts from eight Indonesian medicinal plants were phytochemically screened and evaluated for antiviral (HSV-1 and Poliovirus) and cytotoxic activities on murine and human cancer lines (3LL, L1210, K562, U251, DU145, MCF-7). Besides Melastoma malabathricum (Melastomataceae), the Indonesian Loranthaceae species among which Elytranthe tubaeflora, E. maingayi, E. globosa and Scurrula ferruginea exhibited attractive antiviral and cytotoxic activities. Piper aduncum (Piperaceae) was found active on Poliovirus. S. ferruginea was selected for further studies because of its activity on the U251 glioblastoma cells.