IREB2 and Parkinson disease: Our previous study showed that IRP2 expression is decreased in 1-Methyl-4-phenylpyridinium [MPP(+)]-induced cellular model of PD (Zhang et al., 2009), whereas IRP2 expression is increased in 6-hydroxydopamine (6- OHDA)-treated PD model (Jiang et al., 2010).