CYP2 Activator

Pregnenolone 16α-carbonitrile is an orally active prototypical and effective rodent-PXR activator. Pregnenolone 16α-carbonitrile, a synthetic steroid, induces cytochrome P450 3A expression. Pregnenolone 16α-carbonitrile exhibits increased resistance to subsequent stressful insults.

Phillyrin is isolated from Forsythia suspensa Vahl (Oleaceae), has antibacterial and anti-inflammatory activities. Phillyrin has potential inductive effects on rat CYP1A2 and CYP2D1 activities, without affecting CYP2C11 and CYP3A1/2 activities. Phillyrin has anti-influenza A virus activities.

Fipronil is a broad-spectrum insecticide effective against Lepidoptera species as well as thrips, locusts, ants, cockroaches, fleas and ticks. Fipronil selectively inhibits GABA receptor with IC₅₀s of 30 nM and 1600 nM for cockroach and rat GABA receptors, respectively. Glutamate-gated chloride channels (GluCls), which are present in cockroaches but not in mammals, are sensitive to the blocking effect of Fipronil. Fipronil also induces apoptosis in HepG2 cells and promotes the expression of CYP1A1 and CYP3A4 mRNA in human hepatocytes.