title: Morphological and gene expression analysis in mouse primary cultured hepatocytes exposed to streptozotocin.
abstract: Streptozotocin (SZ) is known to exert toxic effects not only on pancreatic islet beta cells but also on other organs including the liver. For analyzing direct effects of SZ on hepatocytes, we performed morphological analysis and DNA microarray analysis on mouse primary cultured hepatocytes. Hepatocytes were taken from non-treated Crj:CD-1(ICR) mice. The primary cultured hepatocytes were treated with SZ at concentrations of 0, 1, 3, 10, 30 and 100 mM. After the treatment for about 6 or 24h, cell survival assay using tetrazolium salt (WST-1), light microscopic/electron microscopic analysis and gene expression analysis were performed. For the gene expression analysis, target (labeled cRNA) prepared from total RNA of the hepatocytes was hybridized to the GeneChip Murine Genome U74A V.2 (Affymetrix). The signal intensity calculation and scaling were performed using Microarray Suite Software Ver 5.0. IC50 of the cell survival assay was around 62 mM at 6 h exposure and 7 mM at 24 h exposure. Marked chromatin margination was observed in nuclei of the hepatocytes treated with SZ at concentrations of 3 or 10mM. Gene expression analysis revealed similar expression changes to those of in vivo, i.e. up-regulation in cell proliferation/ apoptosis related genes, and down-regulation of lipid metabolism related genes. These results potently supported the hypothesis that many of the hepatic alteration including histopathological and gene expression changes are induced by direct effect of SZ rather than by the secondary effect of the hyperglycemia or hypoinsulinemia.
authors.affiliation: Exploratory Toxicology and DMPK Research Laboratory, Tanabe Seiyaku Co Ltd, 2-2-50, Kawagishi, Toda, Saitama 335, Japan. e-kume@tanabe.co.jp
authors.forename: Eisuke
authors.initials: E
authors.lastname: Kume
authors.forename: Chinami
authors.initials: C
authors.lastname: Aruga
authors.forename: Kaori
authors.initials: K
authors.lastname: Takahashi
authors.forename: Satoko
authors.initials: S
authors.lastname: Miwa
authors.forename: Eriha
authors.initials: E
authors.lastname: Dekura
authors.forename: Masahito
authors.initials: M
authors.lastname: Itoh
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Ishizuka
authors.forename: Hisako
authors.initials: H
authors.lastname: Fujimura
authors.forename: Wataru
authors.initials: W
authors.lastname: Toriumi
authors.forename: Kunio
authors.initials: K
authors.lastname: Doi
mesh_terms: D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000633:toxicity*; D017209:Apoptosis / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D015870:Gene Expression / Q000187:drug effects; D020869:Gene Expression Profiling; D022781:Hepatocytes / Q000187:drug effects* / Q000473:pathology* / Q000648:ultrastructure; D008297:Male; D051379:Mice; D046529:Microscopy, Electron, Transmission; D020411:Oligonucleotide Array Sequence Analysis; D013311:Streptozocin / Q000633:toxicity*
chemical_list: D000903:Antibiotics, Antineoplastic; D013311:Streptozocin