月季花活性成分槲皮素抗烟曲霉的宿主-病原体通路互作机制研究OA

Objective To investigate the multi-target mechanism of quercetin,the main active component of Rosa chinensis(R.chinensis),against Aspergillus fumigatus(A.fumigatus)from the host-pathogen interaction perspective.Methods Firstly,the active components of R.chinensis and host targets related to A.fumigatus infection were screened using TCMSP,GeneCards,and OMIM databases.Virulence and drug resistance-related targets of A.fumigatus were obtained from NCBI and UniProt databases.Cross-species homology mapping was performed using the KEGG Orthology sys-tem,and a Host-Pathogen Pathway Interaction Network(HPPIN)was constructed using Cytoscape 3.10.3.Core targets were identified through topological analysis(degree centrality and betweenness centrality).Secondly,molecular docking of quercetin with the core targets was conducted using AutoDock Vina 1.5.7,with a binding energy threshold of≤-5.0 kcal/mol.The optimal complex was selected for a 100 ns molecular dynamics simulation using GROMACS 2020.6(AMBER99SB force field)to analyze binding stability via root-mean-square deviation(RMSD),root-mean-square fluctuation(RMSF),and hydrogen bond numbers.Finally,following the CLSI M38-A3 protocol,the minimum inhibitory concentration(MIC)of quercetin against the standard A.fumigatus strain Af293 was determined using the broth microdilution method.Phenotypic rescue experiments using a mixture of N-acetylcysteine and purine were performed to validate the predicted interference with oxidative stress and purine metabolism pathways,and hyphal morphological chan-ges were observed under an inverted microscope.Results The HPPIN identified 12 key tar-gets.Quercetin exhibited binding energies of-7.6 kcal/mol with KRas and-7.8 kcal/mol with SA-ICAR synthetase,forming stable complexes(RMSD<0.2 nm).The MIC of quercetin against A.fumigatus was 256 μg/mL,resulting in complete inhibition of hyphal growth.This inhibitory effect was reversed by N-acetylcysteine,confirming the role of oxidative stress.Concurrently,com-bination with high-concentration purine led to complete germination failure,indicating disruption of purine metabolism.Conclusion Quercetin synergistically inhibits A.fumigatus through dual mecha-nisms of"starvation"and"intoxication."