Characterization of the neuroprotective potential of derivatives of the iron chelating drug deferiprone.

There is growing evidence for alterations in iron homeostasis during aging that are exacerbated in neurodegenerative diseases such as Alzheimer's disease. However, since essentially all neurodegenerative diseases are multi-factorial in the sense that there are a large number of mechanisms that can be identified as contributing to nerve cell death, iron chelators that have additional activities might be the most useful for the treatment of age-related CNS diseases. We have described a series of cell culture-based assays that define molecular toxicity pathways relevant to neurodegenerative diseases and have used these assays to identify potential therapeutic compounds for the treatment of these diseases. Deferiprone is a blood brain barrier permeable, low molecular weight iron chelator that has been used for many years to treat systemic iron disease. In this study, we describe the use of our cell culture-based screening assays to identify deferiprone derivatives with the greatest therapeutic potential for the treatment of CNS diseases. We show that several derivatives are much more potent than deferiprone at reducing oxidative stress and preventing nerve cell death induced by multiple, age-related insults. In addition, we show that both deferiprone and the derivatives modulate several distinct signaling pathways associated with neuroprotection. All of the compounds were able to both inhibit the activation of p38 MAP kinase and JNK kinase and prevent the loss of PI3 kinase activity in response to a toxic stress. These results strongly suggest that these compounds have significant potential for the treatment of CNS diseases.