Inhibitory activity and mechanism of oleuropein against Trichophyton mentagrophytes

Abstract:

[Background] Trichophyton mentagrophytes is a common superficial skin pathogen, and dermatophytosis caused by this pathogen has a high incidence, posing a threat to human health. [Objective] To investigate the inhibitory activity and mechanism of oleuropein against T. mentagrophytes. [Methods] We determined the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). RNA-Seq was performed for T. mentagrophytes treated with oleuropein and the obtained sequences were subjected to quality evaluation and information annotation. DESeq2 was used to identify the differentially expressed genes (DEGs), which were then subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. RT-qPCR was conducted to validate the results. [Results] The MIC and MBC of oleuropein against T. mentagrophytes were 400 μg/mL and 800 μg/mL, respectively. A total of 534 DEGs were identified between the treatment group and the control group, including 401 genes with upregulated expression and 133 genes with downregulated expression. The sequence has been submitted to Sequence read archive (SRA) of the NCBI, with the accession number PRJNA1091040. These DEGs were mainly enriched in pathways related to oxidative phosphorylation, amino acid metabolism, and glyoxylate and dicarboxylate metabolism, with significant expression (P<0.05). The RT-qPCR results were consistent with the results from transcriptomics, demonstrating the reliability of RNA-Seq findings. [Conclusion] We investigated the mechanism underlying the inhibitory effect of oleuropein on T. mentagrophytes, providing a theoretical basis for deciphering the antifungal mechanism of oleuropein.