ABSTRACT
ObjectiveTo explore the potential anti-tuberculosis mechanism of Kanglao granule through network pharmacology. MethodThe active components of Kanglao granule were retrieved from related databases and the potential targets of the components from SwissTargetPrediction. Targets of the tuberculosis were screened from GeneCards and National Center for Biotechnology Information （NCBI）， and the anti-tuberculosis targets of the prescription were further identified. STRING and Cytoscape 3.8.0 were employed to construct the Chinese medicinal-disease target-signaling pathway network and screen core targets. Then gene ontology （GO） term enrichment and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway enrichment were performed. Finally， AutoDock Vina was used for molecular docking between the active components of the prescription and key proteins and Western blotting for verifying the interaction between them. ResultA total of 29 important chemical components in the prescription were screened out， including β-sitosterol， sesamin， and kaempferol. A total of 28 key anti-tuberculosis targets were retrieved， such as protein kinase B1 （Akt1）， epidermal growth factor receptor （EGFR）， hypoxia inducible factor-1A （HIF-1A）， proto-oncogene tyrosine-protein kinase （SRC）， and matrix metalloproteinase-9 （MMP-9）. Bioinformatics analysis showed the 28 targets were involved in 41 GO terms such as oxygen metabolism， nucleic acid transcription， and metabolic enzyme pathway， and 28 key KEGG pathways， including Mycobacterium tuberculosis signaling pathway and phosphatidylinositol 3 kinase/protein kinase B pathway. Molecular docking results showed that Akt1 had the strongest binding affinity to sesamin. In vitro experiment indicated that sesamin inhibited the growth of M. tuberculosis by suppressing the phosphorylation of Akt1. ConclusionKanglao granule improved the sterilization level and immune response through multi-component， multi-target， and multi-pathway interactions， thereby achieving therapeutic effect on tuberculosis. Akt1 is one of the important targets involved in the treatment of tuberculosis.
ABSTRACT
MicroRNAs (miRNAs) are small noncoding RNAs that control diverse cellular and developmental events through repression of large sets of target mRNAs. miRNAs expressions were mainly regulated at two levels: transcriptional and post-transcriptional. Transcriptional regulation of miRNA-encoding genes produce specific expression patterns of individual miRNA. However, the mechanism of post-transcriptional regulation of miRNAs remains largely unknown. The present study was aimed to clarify whether HuR, an evolutionary conserved AU-rich binding protein, could regulate miRNAs expressions. By means of a computational screen for AUUUA motifs within pri-miRNAs, we found that the downstream of hsa-let-7c but not hsa-miR-21 was enriched of AUUUA motifs. Then we transfected HuR and mutant HuR lacking RNA recognition motif 3 (RRM3) respectively into HEK293T cells. And HuR protein and miRNAs expressions were detected by Western blot and real-time PCR, respectively. The results showed that the overexpression of HuR promoted mature hsa-let-7c expression but not hsa-miR-21 expression. Furthermore, overexpression of HuR deletion mutant lacking RRM3 did not promote hsa-let-7c expression. These results suggest that RRM3 is crucial for HuR mediating mature hsa-let-7c expression. Collectively, these findings proposed a novel role of HuR in biogenesis of miRNAs, possibly by way of post-transcriptional regulation of miRNAs.