Abstract
Epigallocatechin gallate (EGCG), a major type of green tea polyphenol, has been reported to cause hepatotoxicity when used in excess. Micro-RNAs (miRNAs) are small non-coding RNA molecules that functions as negative regulators of gene expression. They play an important role in the regulation of genes involved in the cellular and molecular responses to toxicants. To examine miRNA regulatory effect on global gene expression in EGCG-treated HepG2 cells, we performed pair-wise correlation coefficient analysis on expression levels of 22 miRNA and 27,419 mRNA, and observed negative correlations (r< −0.7) between miRNA and mRNA. We identified a total of 234 negative correlated miRNA-mRNA pairs. Gene Ontology analysis on the miRNA-correlated genes revealed significant enrichment in the several biological processes related to organic acid metabolic process, carboxylic acid metabolic process and cellular protein catabolic process. Connectivity map analysis also revealed that the expression signatures of EGCG were very similar to those of polyphenol gossypol which is hepatotoxic to animal and human.
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Ahn, JI., Jeong, K.J., Ko, MJ. et al. Changes of miRNA and mRNA expression in HepG2 cells treated by epigallocatechin gallate. Mol. Cell. Toxicol. 6, 169–177 (2010). https://doi.org/10.1007/s13273-010-0024-3
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DOI: https://doi.org/10.1007/s13273-010-0024-3