Inokosterone Is A Potential Drug Target of Estrogen Receptor 1 in Rheumatoid Arthritis Patients: Analysis from Active Ingredient of Cyathula Officinalis

Objective: To elucidate the active compounds and the molecular mechanism of Cyathula Offificinalis as a drug treatment for rheumatoid arthritis (RA). Methods: The target genes of active ingredients from Cyathula Offificinalis were obtained from bioinformatics analysis tool for the molecular mechanism of traditional Chinese medicine. The protein-protein interaction between the target genes were analyzed using STRING and Genemania. The transcriptome of RA patients compared to healthy people (GSE121894) were analyzed using R program package Limma. The relative expression of the target genes was obtained from the RNA-seq datasets. The molecular docking analyses were processed based on the molecular model of estrogen receptor 1 (ESR1) binding with estradiol (PDB ID: 1A52). The binding details were analyzed by SYBYL. Results: Inokosterone, ecdysterone, and cyaterone were the 3 active ingredients from Cyathula Officinalis that bind to target genes. Of all the significantly changed genes from RA patients, ESR1, ADORA1, and ANXA1 were signifificantly increased in mRNA samples of RA patients. Conclusion: ESR1, the transcription factor that binds inokosterone in the molecular binding analysis, is the target protein of Cyathula Offificinalis.