Gene expression profiling predicts liver responses to a herbal remedy after partial hepatectomy in mice

The aim of this study was to demonstrate that regenerating liver responses to a herbal remedy could be presented by gene expression profiling. Compositions of the ingredients in the remedy containing Scutellaria baicalensis Georgi and Bupleurum scorzonerifolfium Wild (S/B remedy) were analyzed and quantified by high performance liquid chromatography. By using a 70% partial hepatectomy in BALB/c mice as an in vivo model, the effects of high dose (50 mg/kg) and low dose (1 mg/kg) S/B remedy were evaluated by cDNA microarray, followed by RT-PCR and real-time PCR confirmation. Factors affecting proliferative activities of mouse hepatocytes were measured by DNA flow cytometry, BrdU incorporation assay and serum interleukin-6 (IL-6) level. Based on global gene expression profiles, the results showed that the low dose S/B remedy down-regulated expression of immediate early genes and cell cycle-related genes, whereas the high dose had opposite effects. The gene expression was further verified by real-time RT-PCR. Proliferative activities, in terms of synthetic phase fractions and G2/M phase fractions, in vehicle, low dose, and high dose groups were 18.45+/-2.56%, 14.65+/-1.06%; 9.27+/-0.85%, 7.80+/-0.11%; and 18.90+/-2.17%, 22.95+/-0.25%, respectively. The serum IL-6 level was also dose-dependent in both low and high dose S/B remedy-treated mice. We conclude that in vivo gene expression profiling correlates with liver responses to a herbal remedy, which provides a new direction for pharmaceutical studies on human diseases.