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The identification of putative circulating miRNA biomarkers of Thioacetamide-induced hepatotoxicity.

ABSTRACT: The Thioacetamide-treated rat was first identified as a model of hepatotoxicity by Gupta in 1956 and is now well-established, not least because the histopathogical output closely mimics that seen in humans with chronic liver disease. Acute treatment of rats with Thioacetamide causes pronounced necrosis and inflammation. Animals received intraperitoneal (ip) doses of vehicle-only (0.9% (v/v) saline) (n=3), or 100 mg/kg Thioacetamide (n=3) and were sacrificed after 24 hours. Blood was withdrawn via the descending vena cava and immediately transferred into potassium/EDTA tubes. Following centrifugation (16,100g, 4°C, 5 min) the plasma was collected and stored at -80°C. miRNA microarray profiling of RNA extracted from the plasma of rats treated with Thioacetamide revealed that a subset of miRNAs were differentially expressed following treatment. These miRNAs appeared to mediate pathways involved in hepatic fibrosis and stellate cell activation, suggesting that they might function as predictive biomarkers following compound-induced hepatotoxicity. The changes correlated well with increases in ALT levels, which are the current gold standard method for determining the extent of liver injury. Furthermore, it is hypothesised that particular aetiologies of liver damage might cause differing expression profiles of miRNAs, thus certain miRNAs could be implemented in a panel-type expression study to distinguish between different types of hepatic injury.

ORGANISM(S): Rattus norvegicus

PROVIDER: GSE55885 | GEO | 2014/03/14

SECONDARY ACCESSION(S): PRJNA241250

REPOSITORIES: GEO

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The identification of putative circulating miRNA biomarkers of Thioacetamide-induced hepatotoxicity.

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