Optimizing separation efficiency of 2-DE procedures for visualization of different superoxide dismutase forms in a cellular model of amyotrophic lateral sclerosis

Neurodegenerative diseases such as Alzheimer disease (AD) and Parkinson disease (PD)
have been associated with increased production of reactive oxygen species. In AD and PD
patients, superoxide dismutase (SOD1) was also indicated as a major target of oxidative
damage. In particular, in brain tissue of these patients, different SOD1 isoforms have been
identified, although their functional role still remains to be elucidated. In the light of the
possibility that different SOD1 entities could be expressed also in other neurodegenerative
disorders, as a sort of unifying event with AD and PD, we have investigated amyotrophic
lateral sclerosis (ALS) using human neuroblastoma SH-SY5Y cells with mutated SOD1
gene H46R as cellular model. 2-DE using a narrow-range IPG 4–7 strips in the first dimension
and linear 15% SDS-PAGE in the second allowed to separate different SOD1
spots. MALDI-TOF MS and CapLC-MS/MS have been used for their complete identification.
This is the first report in which the presence of SOD1 (iso)forms in a cellular model of
ALS has been evidenced.