SB 239063 (SB239063) is a potent and selective p38 MAPKα/β inhibitor with IC50 of 44 nM, showing no activity against the γ- and δ-kinase isoforms.

p38α:44 nM, p38β:44 nM

SB 239063 potently inhibits IL-1 and TNF-α production in LPS-stimulated human peripheral blood monocytes with IC50 of 120 and 350 nM, respectively. [1] In oxygen-glucose-deprived hippocampal slice cultures, SB239063 strikingly reduces the levels of the pro-inflammatory cytokine IL-1beta, causes cell death after oxygen-glucose deprivation and significantly diminishes microglia activation. [2] In human corneal endothelial cell, SB 239063 inhibits TGF-β(2) and FGF-2-induced cell migration. [4]

In both guinea pigs and mice, SB 239063 (10 mg/kg, p.o.) reduces antigen-induced airway eosinophilia. [1] In air- and ozone-exposed C57/BL6 and MKP-1(-/-) mice, SB239063 inhibits bronchial contraction. [3]