Cellagen Technology
p38 MAPK inhibitor
SB203580 is a pyridinylimidazole-based inhibitor of p38-MAPK at an IC50 of 0.3-0.5 uM. [1] It also inhibits PKB phosphorylation at an IC50 of 3-5 uM and blocks the key cell cycle event of retinoblastoma protein phosphorylation in IL-2-stimulated T-cells. SB203580 was found to inhibit the activation of p70S6K, but at a location downstream of PI3K. [1]
Independent studies indicate at concentrations of 10 uM, SB203580 activates phosphorylation of ERK1/2 and JNK, which in turn may activate gene transcription regulated by NF-kB. [2] Similarly, SB203580 was shown to stimulate the phosphorylation and activation of cPLA2, CAMKIIa and arachidonic acid release. [3]
In an L1210 mouse leukemic cell line resistant to vincristine, SB203580 is believed to play a role in the reversal of Pgp-mediated multidrug resistance. [4]



Cellagen Technology
p38 MAPK inhibitor


SB203580 is a pyridinylimidazole-based inhibitor of p38-MAPK at an IC50 of 0.3-0.5 uM. [1] It also inhibits PKB phosphorylation at an IC50 of 3-5 uM and blocks the key cell cycle event of retinoblastoma protein phosphorylation in IL-2-stimulated T-cells. SB203580 was found to inhibit the activation of p70S6K, but at a location downstream of PI3K. [1]
Independent studies indicate at concentrations of 10 uM, SB203580 activates phosphorylation of ERK1/2 and JNK, which in turn may activate gene transcription regulated by NF-kB. [2] Similarly, SB203580 was shown to stimulate the phosphorylation and activation of cPLA2, CAMKIIa and arachidonic acid release. [3]
In an L1210 mouse leukemic cell line resistant to vincristine, SB203580 is believed to play a role in the reversal of Pgp-mediated multidrug resistance. [4]