Altered expression of heat shock protein 110 family members in mouse hippocampal neurons following trimethyltin treatment in vivo and in vitro.
The heat shock protein (Hsp) 110 family is composed of HSP105, APG-1, and APG-2. As the response of these proteins to neuronal damage is not yet fully understood, in the present study, we assessed their expression in mouse hippocampal neurons following trimethyltin chloride (TMT) treatment in vivo and in vitro. Although each of these three Hsps had a distinct regional distribution within the hippocampus, a low level of all of them was observed in the granule cell layer of the dentate gyrus in naïve animals. TMT was effective in markedly increasing the level of these Hsps in the granule cell layer, at least 16h to 4days after the treatment. In the dentate granule cell layer on day 2 after TMT treatment, HSP105 was expressed mainly in the perikarya of NeuN-positive cells (intact neurons); whereas APG-1 and APG-2 were predominantly found in NeuN-negative cells (damaged neurons as evidenced by signs of cell shrinkage and condensation of chromatin). Assessments using primary cultures of mouse hippocampal neurons exposed to TMT revealed that whereas HSP105 was observed in intact neurons rather than in damaged neurons, APG-1 and APG-2 were detected in both damaged neurons and intact neurons. Taken together, our data suggest that APG-1 and APG-2 may play different roles from HSP105 in neurons damaged by TMT.
Yoneyama
Masanori
M
Department of Pharmacology, Setsunan University, Hirakata, Osaka 573-0101, Japan.
Iwamoto
Naoko
N
Nagashima
Reiko
R
Sugiyama
Chie
C
Kawada
Koichi
K
Kuramoto
Nobuyuki
N
Shuto
Makoto
M
Ogita
Kiyokazu
K
D000818:Animals; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology; D053938:DNA Fragmentation; D004622:Embryo, Mammalian; D005786:Gene Expression Regulation / Q000187:drug effects*; D050957:HSP110 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D006624:Hippocampus / Q000166:cytology*; D066298:In Vitro Techniques; D037102:Lectins / Q000378:metabolism; D008565:Membrane Proteins; D051379:Mice; D009419:Nerve Tissue Proteins; D009474:Neurons / Q000378:metabolism / Q000528:radiation effects*; D010751:Phosphopyruvate Hydratase / Q000378:metabolism; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism; D013997:Time Factors; D014298:Trimethyltin Compounds / Q000494:pharmacology*
D050957:HSP110 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D037102:Lectins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D010751:Phosphopyruvate Hydratase; D014298:Trimethyltin Compounds; C485680:Hspa4 protein, mouse; C490237:NNAT protein, human; C099678:Hspa4l protein, mouse; C046488:trimethyltin