Neuroprotective actions of deferiprone in cultured cortical neurones and SHSY‐5Y cells

Abstract

Alzheimer's disease (AD) is a common neurodegenerative disorder, but the initiating molecular processes contributing to neuronal death are not well understood. AD is associated with elevated soluble and aggregated forms of amyloid beta (Abeta) and with oxidative stress. Furthermore, there is increasing evidence for a detrimental role of iron in the pathogenic process. In this context, iron chelation by compounds such as 3-hydroxypyridin-4-one, deferiprone (Ferriprox) may have potential neuroprotective effects. We have evaluated the possible neuroprotective actions of deferiprone against a range of AD-relevant insults including ferric iron, H(2)O(2) and Abeta in primary mouse cortical neurones. We have investigated the possible neuroprotective actions of deferiprone (1, 3, 10, 30 or 100 microM) in primary neuronal cultures following exposure to ferric iron [ferric nitrilotriacetate (FeNTA); 3 and 10 microM], H(2)O(2) (100 microM) or Abeta1-40 (3, 10 and 20 microM). Cultures were treated with deferiprone or vehicle either immediately or up to 6 h after the insult in a 24-well plate format. In order to elucidate a possible neuroprotective action of deferiprone against Parkinson's disease relevant insults another group of experiments were performed in the human neuroblastoma catecholaminergic SHSY-5Y cell line. SHSY-5Y cells were treated with MPP(+) iodide, the active metabolite of the dopaminergic neurotoxin MPTP and the neuroprotective actions of deferiprone evaluated. Cytotoxicity was assessed at 24 h by lactate dehydrogenase release, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium-bromide turnover (FeNTA and hydrogen peroxide) and morphometric analysis of cell viability by Hoechst 33324/propidium iodide (FeNTA, Abeta and MPP(+)) or 6-carboxyfluorescein diacetate and annexin V-Cy3 (Abeta). The present study demonstrates that deferiprone protects against FeNTA, hydrogen peroxide, MPP(+) and Abeta1-40-induced neuronal cell death in vitro, which is consistent with previous in vitro and in vivo studies that have demonstrated similar protection with other iron chelators.

Iron accumulation confers neurotoxicity to a vulnerable population of nigral neurons: implications for Parkinson’s disease

“…We used two methods of targeting iron, CP supplementation therapy, which promotes cellular iron export, and DFP, which binds free iron. CP [4] and DFP [24] have been shown previously to rescue MPTP neurotoxicity and, as expected, lessened MPTP-induced neuronal loss in WT and CP KO mice (Recovered to ~4100 neurons in each case; Figure  3b). Rescue of iron elevation was evident in CP KO mice for both CP and DFP (Figure  3a), but the bulk iron levels in WT MPTP nigra were unchanged by either treatment.To test for drug specificity, we measured liver iron content in the same mice.…”

Inhibition of Prolyl Hydroxylase Protects against 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced Neurotoxicity

“…8B, *, p Ͻ 0.05 between control/control and DHB/control; #, p Ͻ 0.05 between control/MPP ϩ and DHB/MPP ϩ ). Although iron chelators have been shown to be protective against MPP ϩ neurotoxicity (24,40), it was determined that PHD inhibition by DHB was also able to attenuate cell death associated with a toxic concentration of MPP ϩ (Fig. 8C, *, p Ͻ 0.005 between control/control and control/MPP ϩ ; ∧, p Ͻ 0.001 between control/ MPP ϩ and DHB/MPP ϩ ), results that parallel those observed in vivo (Fig.…”

AMPA Receptor Activation Promotes Non-Amyloidogenic Amyloid Precursor Protein Processing and Suppresses Neuronal Amyloid-β Production

“…Primary cortical neurons cultured for 10 DIV were treated with AMPA (50 µM) for 20 min to 24 h. AMPA-induced cytotoxicity was evaluated by release of the cytosolic enzyme LDH into the culture medium using the CytoTox 96 non-radioactive cytotoxicity assay according to the manufacturer's instructions (Promega, Madison, WI), as described previously [24]. Absorbance was measured at 490 nm using a VersaMax microplate reader.…”