Unraveling the Mechanism of Zhibaidihuang Decoction against IgA Nephropathy Using Network Pharmacology and Molecular Docking Analyses

Zhibaidihuang Decoction (ZBDHD) is a traditional Chinese medicine with immense potential to treat IgA nephropathy. However, its core ingredients and representative mechanism remain unclear. In this study, we uncovered the key component and underlying mechanisms of ZBDHD for IgA nephropathy by applying network pharmacology and molecular docking approaches. This was done by first identifying the active ingredients and, subsequently, their corresponding gene targets in ZBDHD with the help of the Traditional Chinese Medicine Systems Pharmacology and analysis platform (TCMSP) database, thereby constructing the drug-compound-target network. The IgA nephropathy-associated genes were then identified using GeneCards, Drugbank, and OMIM databases. The overlapped targets were later obtained to establish Protein-Protein Interaction (PPI) networks, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Finally, we performed molecular docking among active compounds and hub genes, and thereby verified the key compound of ZBDHD. The drug-compound-gene network consisted of 289 nodes and 1,113 edges. The top four active ingredients were beta-sitosterol, kaempferol, quercetin and stigmasterol. The top five hub genes in the PPI network were AKT1, ILB1, IL-6, TNF, and TP53. Molecular docking results could demonstrate that there was high affinity among active compounds and the core targets, while quercetin may possibly be the key compound of ZBDHD. We first identified the positive compound and the candidate molecular mechanisms of ZBDHD in an IgA nephropathy treatment and discovered that quercetin might be the core compound of ZBDHD in the treatment of IgA nephropathy.