Biomarkers for aristolochic acid nephrotoxicity

Aristolochic acid (AA) is a major ingredient in several Chinese herbs that exhibits a wide range of pharmacological effects. Recently, clinical reports and experimental studies have demonstrated that AA causes renal toxicities, acute renal failure and interstitial fibrosis.However, the molecular mechanism underlying AA nephrotoxicity is not yet fully understood. Embryonic stem cells (ESCs) are pluripotent cells isolated from early embryos, which have highly undifferentiated potential and are capable of differentiating into all kinds of body tissues and organs. It has been reported that ESCs are sensitive to drug stimulation, and thus may serve as important tools for in vitro assessment of drug toxicity. We aimed to identify accurate biomarkers of AA-induced renal toxicity on ESCs. Genomics analysis was performed to screen the changes in gene expression levels of ESCs following treatment with AA, in order to determine the potential biological processes in which AA induces renal toxicity. MTT assay was performed to determine the cytotoxicity of aristolochic acid in ESCs. Differentially expressed genes (DEGs) were identified using the DNA-Chip Analyzer following microarray analysis. Gene Ontology analysis was performed to determine representative categories of biological processes. Cellular component and molecular function were assessed to further understand the gene functions. DEGs were subjected to Kyoto Encyclopedia of Genes and Genomes analysis to determine representative pathways, and the network was constructed using Cytoscape 3.2 software. PERP, cation transport regulator-like 1 (Chac1), Adrb2 and Wnt6 were selected for reverse transcription-quantitative (RT-q)PCR analysis