ABSTRACT
The P4 region of a series of oxamyl dipeptide caspase inhibitors was optimized by the combination of anti-apoptotic activity in the Jurkat/Fas (JFas) cellular assay and membrane permeability in the PAMPA assay. Two highly potent anti-apoptotic agents with moderate membrane permeability, 29 and 36, showed strong in vivo efficacy in a murine model of alpha-Fas-induced liver injury.
Subject(s)
Caspase Inhibitors , Cysteine Proteinase Inhibitors/chemical synthesis , Liver Diseases/drug therapy , Animals , Apoptosis/drug effects , Cell Membrane Permeability/drug effects , Cysteine Proteinase Inhibitors/pharmacology , Humans , Jurkat Cells , Mice , Structure-Activity Relationship , fas ReceptorABSTRACT
In a mouse model of alpha-Fas-induced acute liver injury, the orally-administered caspase inhibitor PF-03491390 (formerly named IDN-6556) was retained in the liver for prolonged periods with a low systemic exposure. Reductions in the elevated plasma levels of alanine aminotransferase (ALT) revealed that the retention of PF-03491390 in the liver exerted a hepatoprotective effect, even when pre-administered to mice 4 h before alpha-Fas insult. Prolonged retention of PF-03491390 in the liver after oral administration has the benefit of low systemic exposure, making this a beneficial agent for the treatment of liver diseases.
Subject(s)
Caspase Inhibitors , Enzyme Inhibitors/pharmacology , Liver Diseases/drug therapy , Pentanoic Acids/pharmacology , Administration, Oral , Alanine Transaminase/blood , Alanine Transaminase/drug effects , Animals , Antibodies, Monoclonal/toxicity , Antibodies, Monoclonal, Murine-Derived , Apoptosis/drug effects , Chemical and Drug Induced Liver Injury , Disease Models, Animal , Drug Administration Schedule , Drug Delivery Systems , Enzyme Inhibitors/administration & dosage , Enzyme Inhibitors/pharmacokinetics , Liver/metabolism , Male , Mice , Mice, Inbred BALB C , Pentanoic Acids/administration & dosage , Pentanoic Acids/pharmacokinetics , Tissue DistributionABSTRACT
Gene transfection is a fundamental technology for molecular and cell biology, and also clinical gene therapy. A variety of non-viral vectors have been investigated for gene transfection, but their gene delivery had remained an inefficient process. Recently, we found that a biosurfactant, mannosylerythritol lipid (MEL)-A, dramatically increased the efficiency in transfection of plasmid DNA mediated by cationic liposomes. However, its mechanism has not been understood yet. Here we examined the mechanism of the transfection mediated by cationic liposomes with NBD-conjugated MEL-A. We found that MEL-A first gradually distributed on the intracellular membranes through the plasma membranes of target cells, while the cationic liposomes with MEL-A fused to the plasma membranes in 20-35 min. Thereafter, the oligonucleotide released from the vesicles was immediately transferred to the nucleus. The present results showed a new role of non-viral vectors in transfection.
Subject(s)
Cell Membrane/metabolism , DNA/metabolism , Glycolipids/chemistry , Nitrobenzenes/chemistry , Oligonucleotides/metabolism , Oxadiazoles/chemistry , Surface-Active Agents/chemistry , Transfection/methods , Active Transport, Cell Nucleus , Androstadienes/pharmacology , Animals , Cations , Cell Membrane/drug effects , Cell Nucleus/metabolism , DNA/chemistry , Endocytosis , Fluorescein-5-isothiocyanate/metabolism , Fluorescent Dyes/metabolism , Genes, Reporter , Intracellular Membranes/metabolism , Lipids/chemistry , Liposomes , Luciferases/genetics , Membrane Fusion , Mice , Models, Molecular , Molecular Conformation , NIH 3T3 Cells , Oligonucleotides/chemistry , Time Factors , WortmanninABSTRACT
Recently we showed significance of biosurfactants in the field of non-viral vectors for gene transfection. There, a biosurfactant, mannosylerythritol lipid A (MEL-A), especially increased the efficiency of gene transfection mediated with cationic liposomes. However, the molecular mechanism has not been well-understood yet. Here, through the examination of the ability of cationic liposomes containing an MEL (MEL-A, MEL-B or MEL-C) for important transfectional processes of the DNA capsulation and the membrane fusion with anionic liposomes, we found that MEL-A-containing liposomes increased both processes, but that MEL-B and MEL-C-containing liposomes just increased either of them. The results indicated that these kinds of the physicochemical properties in MEL-A-containing liposomes are able to increase the efficiency of liposome-mediated gene transfection.
