RESUMO
We have investigated the interaction of liposomes with the continuous cell lines P388D1 and L-132 and mouse peritoneal macrophages. To distinguish the liposomes from other vesicular structures, we have used liposomes with incorporated protein G and gold. A heterogeneous mixture of multilamellar liposomes 30 nm up to 1000 nm in size has been employed. Samples were examined at different time intervals. We found differences in the uptake of liposomes with regard to size and rate. Cells of a P388D1 monolayer took up liposomes by endocytosis very early after addition of liposomes and the number of lysosomes in their cytoplasm increased. In L-132 cells, first a fusion occurred between liposomes and the cell cytoplasmic protrusions, in the cytoplasm of which the mitochondria had multiplied. Peritoneal macrophages phagocytosed mainly large multilamellar liposomes and the membranous system of Golgi apparatus was the most prominent structure in the cytoplasm. Phagocytosis in P388D1 and L-132 cells was noted sporadically as late as 24 h after addition of liposomes to the cells.
Assuntos
Lipossomos/metabolismo , Macrófagos Peritoneais/metabolismo , Microscopia Eletrônica/métodos , Animais , Linhagem Celular , Citoplasma/metabolismo , Ouro/metabolismo , Complexo de Golgi/ultraestrutura , Humanos , Pulmão/citologia , Pulmão/embriologia , Macrófagos Peritoneais/ultraestrutura , Camundongos , Camundongos Endogâmicos BALB C , Proteínas do Tecido Nervoso/metabolismo , Fagocitose , Fatores de Tempo , Vacúolos/metabolismoRESUMO
To verify the penetration of liposomes through skin, we have used liposomes with encapsulated protein G-gold conjugate in a gel vehicle. Skin samples were examined 2, 4, 24, 48, and 72 h after liposome application. Our findings show that the penetration of liposomes through skin depends mainly on their size. Liposomes up to 600 nm in diameter penetrate through skin rather easily, whereas liposomes 1000 nm and more in diameter remain interiorized in the stratum corneum. The main penetration of liposomes proceeds along the hair sheaths as indicated by larger amounts of free liposomes in the corium of guinea pigs.
Assuntos
Lipossomos/metabolismo , Lipossomos/farmacocinética , Pele/efeitos dos fármacos , Pele/ultraestrutura , Animais , Endocitose , Ouro/metabolismo , Cobaias , Folículo Piloso/metabolismo , Humanos , Queratinócitos/metabolismo , Macrófagos/metabolismo , Microscopia Eletrônica/métodos , Coelhos , Pele/metabolismo , Fatores de Tempo , Vitamina A/farmacologiaRESUMO
The antiphlogistic Ibuprofen incorporated in liposomes caused a decrease of the inflammatory edema induced by Carrageenan in the distal part of the rat's hind leg after both the intramuscular and percutaneous administration. The antiphlogistic effect of free Ibuprofen in the cream was weaker. Intramuscular administration of empty liposomes slowed down in the initial stages the development of inflammation and slightly diminished the size of edema.