title: Use of a low-density microarray for studying gene expression patterns induced by hepatotoxicants on primary cultures of rat hepatocytes.
abstract: In the field of gene expression analysis, DNA microarray technology is having a major impact on many different areas including toxicology. For instance, a number of studies have shown that transcription profiling can generate the information needed to assign a compound to a mode-of-action class. In this study, we investigated whether compounds inducing similar toxicological endpoints produce similar changes in gene expression. In vitro primary rat hepatocytes were exposed to 11 different hepatotoxicants: acetaminophen, amiodarone, clofibrate, erythromycin estolate, isoniazid, alpha-naphtylylisothiocyanate, beta-naphtoflavone, 4-pentenoic acid, phenobarbital, tetracycline, and zileuton. These molecules were selected on the basis of their variety of hepatocellular effects observed such as necrosis, cholestasis, steatosis, and induction of CYP P450 enzymes. We used a low-density DNA microarray containing 59 genes chosen as relevant toxic and metabolic markers. The in vitro gene expression data generated in this study were generally in good agreement with the literature, which mainly concerns in vivo data. Furthermore, gene expression profiles observed in this study have been confirmed for several genes by real-time PCR assays. All the tested drugs generated a specific gene expression profile. Our results show that even with a relatively limited gene set, gene expression profiling allows a certain degree of classification of compounds with similar hepatocellular toxicities such as cholestasis, necrosis. The clustering analysis revealed that the compounds known to cause steatosis were linked, suggesting that they functionally regulate similar genes and possibly act through the same mechanisms of action. On the other hand, the drugs inducing necrosis and cholestasis were pooled in the same cluster. The drugs arbitrarily classified as the CYP450 inducers formed individual clusters. In conclusion, this study suggests that low-density microarrays could be useful in toxicological studies.
authors.affiliation: Eppendorf Array Technology (EAT), 20, Rue du Séminaire, 5000 Namur, Belgium. delongueville.f@eppendorf.be
authors.forename: Francoise
authors.initials: F
authors.lastname: de Longueville
authors.forename: Franck A
authors.initials: FA
authors.lastname: Atienzar
authors.forename: Laurence
authors.initials: L
authors.lastname: Marcq
authors.forename: Simon
authors.initials: S
authors.lastname: Dufrane
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Evrard
authors.forename: Lydia
authors.initials: L
authors.lastname: Wouters
authors.forename: Florence
authors.initials: F
authors.lastname: Leroux
authors.forename: Vincent
authors.initials: V
authors.lastname: Bertholet
authors.forename: Brigitte
authors.initials: B
authors.lastname: Gerin
authors.forename: Rhys
authors.initials: R
authors.lastname: Whomsley
authors.forename: Thierry
authors.initials: T
authors.lastname: Arnould
authors.forename: José
authors.initials: J
authors.lastname: Remacle
authors.forename: Mickael
authors.initials: M
authors.lastname: Canning
mesh_terms: D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D004790:Enzyme Induction / Q000187:drug effects; D005562:Formazans / Q000378:metabolism; D020869:Gene Expression Profiling; D022781:Hepatocytes / Q000187:drug effects* / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013778:Tetrazolium Salts / Q000378:metabolism; D015262:Xenobiotics / Q000145:classification / Q000633:toxicity*
chemical_list: D005562:Formazans; D012333:RNA, Messenger; D013778:Tetrazolium Salts; D015262:Xenobiotics; C079782:MTT formazan; D003577:Cytochrome P-450 Enzyme System