Proteomic analysis of human cerebral cortex in epileptic patients

Abstract

Abbreviations: 2-DE, 2-dimensional electrophoresis; ESI-Q-TOF, electrospray ionization quadupole time of flight; GPDH, Glycerol phosphate dehydrogenase; GPX, glutathione peroxidase; MALDI-TOF, matrix-assisted laser desorption/ionization-time-of flight; SOD, superoxide dismutase A bstractEpilepsy affects m ore than 0.5% of the w orld population and is know n to be associated w ith a large genetic com ponent eliciting an electrical hyperexcitability in the central nervous system . However, its pathogenic m echanism s rem ain poorly understood. In order to gain greater m olecular incite in the pathogenesis in epilepsy, we analyzed proteom es of hum an cerebral cortices. Q uantitative proteom e analysis w as used to com pare signals corresponding to individual proteins betw een epileptic cerebral cortices from patients w ith temporal lobe epilepsy and age-m atched non-epileptic subjects. To m inim ize individual variations, gender and age of the patients w ere m atched. Changes of several spots w ere consistent am ong 6 pairs of epileptic patients and nonepileptic subjects. O ne of the spots w as identified as the m itochondrial type Mn-superoxide dism utase (M n-SOD) confirm ed by W estern blot analysis w ith M n-SO D antibody and enzym e activity assay. Such results w ere agreeable w ith chem ical and physical param eters given by the 2-dim ensional electrophoresis (2-DE) gel. M n-SO D w as consistently dow n-regulated in epileptic cerebral cortices com pared w ith those of nonepileptic subjects. Our results dem onstrate a clear link betw een pathogenesis of epilepsy and SO D. Additionally, w e identified four proteins that w ere consistently over-expressed in all epileptic tem poral neocortices specim ens and the other four proteins that w ere found to be expressed less than non-epileptic control subjects. These proteom ic data provide cellular m arkers in the understanding mechanism of the epilepsy pathogenesis.

Age-related decline in expression of calnexin

“…Over the years, many theories of aging have been proposed in the field of aging research, but none of these theories are clearly testified yet. Therefore, it has been recently suggested that proteomics could offer great potential for molecular studies of biological aging and medicine (Dierick et al, 2002;Seong et al, 2002;Schoneich, 2003;Eun et al, 2004). As shown in Figure 3, no difference in calnexin level with aging was detected by Western blotting.…”

Nicotinamide N-methyltransferase protein expression in renal cell cancer

“…Proteomic technologies and DNA microarray are providing the tools needed to discover and identify biomarkers associated with diverse diseases and biological processes (Hanash, 2003;Eun et al, 2004;Yao et al, 2005). NNMT was one of the potential tumor biomarkers identified recently by those technologies, in which NNMT in both mRNA and protein levels was found over-expressed in a wide range of tumors.…”

Generalization of seizures parallels the formation of “dark” neurons in the hippocampus and pontine reticular formation after focal–cortical application of 4-aminopyridine (4-AP) in the rat

“…During electrographic seizures and sustained depolarization, the elevated intracellular Ca ++ can result in both pathological and protective changes in the cellular protein composition of neurons or glial cells. These changes in the cellular proteom are under intense investigation in epilepsy research (Eun et al, 2004;Greene et al, 2007;Jiang et al, 2007;Junker et al, 2005;Ryu et al, 2007;Yang et al, 2006). Some of the available results emphasize the role of cytoskeletal impairment and cytoskeletal rearrangement in epilepsy (Greene et al, 2007;Ryu et al, 2007;Yang et al, 2006).…”