Steroidal and triterpenoidal fungal metabolites as ligands of liver X receptors.

Cholesterol homeostasis is tightly controlled process that involves a variety of regulators including liver X receptors (LXR). Agonists of LXR are expected to increase cholesterol efflux, lower LDL, and raise HDL levels. Screening of a natural product library of microbial extracts using a LXR-scintillation proximity assay (SPA) binding assay and bioassay-guided fractionation of a number of fungal extracts led to the isolation of five ergostane and a cycloartane derivative.

Anthrabenzoxocinones from Streptomyces sp. as liver X receptor ligands and antibacterial agents.

Liver X receptors (LXR) are nuclear hormone receptors that play a critical role in cholesterol homeostasis. They regulate the expression of the ABCA1 gene, which mediates the efflux of cholesterol out of cells. LXR agonists are expected to increase cholesterol efflux, lower LDL, and raise HDL levels.

Diterpenoid, steroid, and triterpenoid agonists of liver X receptors from diversified terrestrial plants and marine sources.

It has been demonstrated that liver X receptors (LXR) play a significant role in cholesterol homeostasis. Agonists of LXR are expected to increase cellular cholesterol efflux, lower LDL, and raise HDL levels. Screening of a natural product library of plant extracts using a LXR-SPA binding assay and bioassay-guided fractionation of a number of plant and marine gorgonian extracts led to the isolation of a number of active compounds.

Guttiferone I, a new prenylated benzophenone from Garcinia humilis as a liver X receptor ligand.

Liver X receptors (LXR) have been implicated in cholesterol homeostasis. Agonists of LXR are expected to increase cholesterol efflux, lower LDL, and raise HDL levels. Screening of a natural product library of plant extracts using a LXR-SPA binding assay and bioassay-guided fractionation of the bark and stem extract of Garcinia humilis led to the discovery of a new polyisoprenylated benzophenone named guttiferone I (1).

Hinnuliquinone, a C2-symmetric dimeric non-peptide fungal metabolite inhibitor of HIV-1 protease.

HIV-1 protease is one of several key enzymes required for the replication and maturation of HIV-1 virus. An almost two-decade research effort by academic and pharmaceutical institutions resulted in the successful commercialization of seven drugs that are potent inhibitors of HIV-1 protease activity and which, if used correctly, are highly effective in managing viral load. However, identification of clinical viral isolates that are resistant to these drugs indicates that this is a significant problem and that new classes of inhibitors are continually needed.