Ro 31-8220 (mesylate)

Ro 31-8220 mesylate is a potent PKC inhibitor, with IC₅₀s of 5, 24, 14, 27, 24 and 23 nM for PKCα, PKCβI, PKCβII, PKCγ, PKCε and rat brain PKC, respectively. Ro 31-8220 also significantly inhibits MAPKAP-K1b, MSK1, S6K1 and GSK3β (IC₅₀s, 3, 8, 15, and 38 nM, respectively), with no effect on MKK3, MKK4, MKK6 and MKK7. Ro 31-8220 mesylate can also inhibit the expression of MKP-1, induce the expression of c-Jun, and activate JNK, and these effects possess pharmacological properties independent of PKC^{[1][2][3][4][5]}. IC50 & Target:IC50: 5 nM (PKCα), 24 nM (PKCβI), 14 nM (PKCβII), 27 nM (PKCγ), 24 nM (PKCε), 23 nM (Rat brain PKC)^[1], 3 nM (MAPKAP-K1b), 8 nM (MSK1), 15 nM (S6K1), 38 nM (GSK3β)^[2] In Vitro:Ro 31-8220 mesylate is a potent PKC inhibitor, with IC₅₀s of 5, 24, 14, 27, 24 and 23 nM for PKCα, PKCβI, PKCβII, PKCγ, PKCε and rat brain PKC, respectively^[1]. Ro 31-8220 also significantly inhibits MAPKAP-K1b, MSK1, S6K1 and GSK3β (IC₅₀s, 3, 8, 15, and 38 nM, respectively), with no effect on MKK3, MKK4, MKK6 and MKK7. Moreover, Ro 31-8220 directly suppresses voltage-dependent Na⁺ channels^[2]. Ro 31-8220 (1 μM) is neuroprotective against paraoxon-induced neuronal cell death in cerebellar granule neurons, blocks paraoxon-induced caspase-3 activity, and reduces the paraoxon-induced increase in phospho-PKC pan levels^[3]. In Vivo:Ro 31-8220 (6 mg/kg/d, s.c.) is well tolerated, and has half-life of 5.7 hours in mice. Ro 31-8220-treated MLP ^/ mice show a dramatic rescue in fractional shortening after treatment for 6 weeks, but the WT mice shows no change^[4].