ABSTRACT
MicroRNAs(miRNA) are small non-coding RNAs that regulate the expression of protein coding genes by repressing translation of protein coding mRNA or enhancing mRNA degradation. Its functions have attracted more and more attention from the public. In recent years, the cross-border regulation of miRNA has become a new research direction, and provides a new perspective for people to comprehensively understand the functions of miRNA. Plant miRNA is usually methylated and not easy to degrade. According to our previous researches, there were abundant small RNAs in the decoction of dried liquorice, which provides a new way to study the mechanism of action of licorice. In this study, small RNAs extracted from Glycyrrhiza uralensis decoction and synthesized miRNA mimics were used to treat peripheral blood mononuclear cells(PBMC) isolated from healthy volunteers. The gene expression of toll-like receptors(TLRs), some transcription factors, signal molecules and cytokines were analyzed by RT-PCR. The results showed that glycyrrhiza miRNA could significantly regulate PBMC by inhibiting the expression of genes involved in T cell differentiation, inflammation and apoptosis. The study brought new ideas to us in comprehensively studying the mechanism of licorice and developing the traditional Chinese medicine.