Synthesis and structure-activity relationships of oxamyl dipeptide caspase inhibitors developed for the treatment of liver disease.

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.

Orally-administered caspase inhibitor PF-03491390 is retained in the liver for prolonged periods with low systemic exposure, exerting a hepatoprotective effect against alpha-fas-induced liver injury in a mouse model.

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.

NBD-conjugated biosurfactant (MEL-A) shows a new pathway for transfection.

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.

Characterization of biosurfactant-containing liposomes and their efficiency for gene transfection.

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.