Abstract: The present invention relates to topical compositions containing a dispersion of composite particles. Each of such composite particles contains one or more core particles encapsulated or entrapped in a polymeric shell. At least some of the core particles are formed of a material capable of causing generation of reactive oxygen species (ROS). Each of the composite particles further contains: (1) a first antioxidant co-encapsulated or co-entrapped with the core particles inside the polymeric shell for quenching or scavenging ROS generated in the vicinity of the core particles, and (2) a second antioxidant coated over the polymeric shell for preventing or reducing oxidative damage to the skin, such as lipid peroxidation. The particle dispersion of the present invention therefore can be readily formulated into topical sunscreen compositions with organic sunscreen agents susceptible to oxidative decomposition or degradation to provide improved protection against skin damage caused by exposure to UV light.

Abstract: Compositions and methods for enhancing repair of damaged DNA in skin cells. Topical compositions comprising at least one agent that upregulates circadian gene expression in skin cells and at least one non-circadian agent that delays mitosis in skin cells. Preferably, such compositions comprise one or more keratinocyte clock and per1 gene activators, along with SIRT1 or one or more sirt1 activators. More preferably, the sirt1 activator is a synergistic combination of specific peptidic sirt1 activators and resveratrol. Preferably, such compositions are easy to use, efficacious, cosmetically acceptable, chemically, thermodynamically and light stable, safe for topical use, have little or no side effects, and commercially feasible in a personal care marketplace.

Abstract: A skin care composition comprising at least one keratinocyte CLOCK or PER1 gene activator and at least one DNA repair enzyme; a method for inhibiting damage to human keratinocytes due to environmental aggressors by applying a composition comprising at least one keratinocyte CLOCK or PER1 gene activator and at least one DNA repair enzyme; and a method for repairing DNA damage in human keratinocytes.

Abstract: Polyampholytes including fibronectin and aggrecan are made to aggregate and form fibrillar lattice networks environment free of cells, extraneous proteins and other materials which may be present in an extracellular matrix. A composition having sufficient charge density is utilized to cause aggregation and self-assembly of such polyampholytes and to provide an assay for determining the effects of environmental agents on such aggregation and self-assembly.

Abstract: Polyampholytes including fibronectin and aggrecan are made to aggregate and form fibrillar lattice networks environment free of cells, extraneous proteins and other materials which may be present in an extracellular matrix. A composition having sufficient charge density is utilized to cause aggregation and self-assembly of such polyampholytes and to provide an assay for determining the effects of environmental agents on such aggregation and self-assembly.