title: Increased metallothionein I/II expression in patients with temporal lobe epilepsy.
abstract: In the central nervous system, zinc is released along with glutamate during neurotransmission and, in excess, can promote neuronal death. Experimental studies have shown that metallothioneins I/II (MT-I/II), which chelate free zinc, can affect seizures and reduce neuronal death after status epilepticus. Our aim was to evaluate the expression of MT-I/II in the hippocampus of patients with temporal lobe epilepsy (TLE). Hippocampi from patients with pharmacoresistant mesial temporal lobe epilepsy (MTLE) and patients with TLE associated with tumor or dysplasia (TLE-TD) were evaluated for expression of MT-I/II, for the vesicular zinc levels, and for neuronal, astroglial, and microglial populations. Compared to control cases, MTLE group displayed widespread increase in MT-I/II expression, astrogliosis, microgliosis and reduced neuronal population. In TLE-TD, the same changes were observed, except that were mainly confined to fascia dentata. Increased vesicular zinc was observed only in the inner molecular layer of MTLE patients, when compared to control cases. Correlation and linear regression analyses indicated an association between increased MT-I/II and increased astrogliosis in TLE. MT-I/II levels did not correlate with any clinical variables, but MTLE patients with secondary generalized seizures (SGS) had less MT-I/II than MTLE patients without SGS. In conclusion, MT-I/II expression was increased in hippocampi from TLE patients and our data suggest that it is associated with astrogliosis and may be associated with different seizure spread patterns.
authors.affiliation: Department of Neuroscience and Behavior, Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto-São Paulo, Brazil.
authors.forename: José Eduardo
authors.initials: JE
authors.lastname: Peixoto-Santos
authors.forename: Orfa Yineth
authors.initials: OY
authors.lastname: Galvis-Alonso
authors.forename: Tonicarlo Rodrigues
authors.initials: TR
authors.lastname: Velasco
authors.forename: Ludmyla
authors.initials: L
authors.lastname: Kandratavicius
authors.forename: João Alberto
authors.initials: JA
authors.lastname: Assirati
authors.forename: Carlos Gilberto
authors.initials: CG
authors.lastname: Carlotti
authors.forename: Renata Caldo
authors.initials: RC
authors.lastname: Scandiuzzi
authors.forename: Luciano Neder
authors.initials: LN
authors.lastname: Serafini
authors.forename: João Pereira
authors.initials: JP
authors.lastname: Leite
mesh_terms: D000328:Adult; D004833:Epilepsy, Temporal Lobe / Q000378:metabolism*; D005260:Female; D005455:Fluorescent Antibody Technique; D006624:Hippocampus / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D008297:Male; D008668:Metallothionein / Q000378:metabolism*; D008875:Middle Aged
chemical_list: D008668:Metallothionein