Dexamethasone is an anti-inflammatory glucocorticoid that induces the production of phospholipase A2 inhibitory protein (lipocortin). Dexamethasone also inhibits induction of nitric oxide synthase (IC50=5 nM). Dexamethasone has been shown to cause reduction in cyclin A and Cdk2 activity, inhibition of G1/S transition in osteoblasts and inhibition of phosphorylation of Rb protein. Dexamethasone has been observed to induce apoptosis in human thymocytes and eosinophils. Conversely, Dexamethasone has also been observed to inhibit apoptosis in neutrophils.