Spectrum-effect relationship combined with bioactivity evaluation to discover the main antidepressant active components of Baihe Dihuang decoction

The study utilized spectral correlation analyses combined with bioactivity evaluation to examine the effective components of antidepressants in the Baihe Dihuang decoction. Firstly, the chemical fingerprints for different extraction parts in the Baihe Dihuang decoction were achieved using HPLC and UHPLC-MS technology. Then, in order to evaluate the antidepressant effect of Baihe Dihuang decoction, the animal experimental protocol has been reviewed and approved by Laboratory Animal Ethics Committee of Hunan University of Chinese Medicine (No. LLBH-202104270001), in compliance with the Institutional Animal Care Guidelines. We recorded the distance of autonomous movement of mice in open field experiment, the immobility time of tail suspension test, and the forced swimming. Additionally, we measured the content of neurotransmitters. Finally, Pearson analysis, grey correlation analysis, and orthogonal partial least squares regression analysis were utilized to establish the correlation between antidepressant efficacy indicators and fingerprinting. The spectrum-effect relationship results were confirmed through the in vitro activity verification. This study demonstrated that regaloside A, B, C, catalpol, and Isoacteoside might be the main antidepressant components in Baihe Dihuang decoction. Furthermore, it was found that using diverse mathematical models and bioactivity evaluation could enhance the accuracy of the spectral correlation analyses results.