Pifithrin-α, p-Nitro, Cyclic

Pifithrin-α, p-Nitro, Cyclic (PFN-α) is cell-permeable and active-form p53 inhibitor. Pifithrin-α, p-Nitro, Cyclic is one order magnitude more active than Pifithrin-α in protecting cortical neurons exposed to Etoposide (ED₅₀=30 nM). Pifithrin-α, p-Nitro, Cyclic behaves as a p53 posttranscriptional activity inhibitor. Pifithrin-α, p-Nitro, Cyclic do not prevent p53 phosphorylation on the S15 residue^[1][2]. In Vitro: Pifithrin-α, p-Nitro, Cyclic (PFN-α) efficiently blocks p53-triggered cell death and p21/WAF1 expression in cortical neurons exposed to etoposide at concentrations one order magnitude lower than that in PFT-α^[1]. In Vivo: Intraocular injection of pifithrin-α slightly increases survival of retinal ganglion cell (RGC) at the concentration of 6 μM but not at 0.06 μM. Pifithrin-α, p-Nitro, Cyclic (PFN-α) is not effective in vivo, even at 6 μM^[1].
Pifithrin-α, p-Nitro, Cyclic shows the half-life (t_1/2) of 6 hours (when incubated in biological conditions)^[1].