Abstract
Background: Sinopodophyllum hexandrum (S. hexandrum) is a typical Chinese herbal medicine with numerous components and remarkable pharmacological activities. However, the specific phytochemicals responsible for its anti-proliferative, anti-inflammatory and anti-viral effects remain unexplored.Methods: The integrated analytical strategy combining bio-affinity ultrafiltration with multiple drug targets was developed to rapidly screen and identify bioactive ligands from S. hexandrum. The in vitro anti-proliferative and COX-2 inhibitory assays of bioactive ligands screened were further verified by sulforhodamine B (SRB) cell proliferation and cytotoxicity detection and COX-2 inhibitor screening kits, respectively. Molecular docking analysis was also implemented by the AutoDockTools 1.5.6 software.Results: 10, 7, 9 and 9 phytochemicals were screened out and identified as the potential Topo I, Topo II, COX-2 and ACE2 ligands, respectively. Hereinto, podophyllotoxin and quercetin with higher EF values displayed strong inhibitory effects on A549 and HT-29 cells comparable with etoposide and 5-FU. Furthermore, compared with indomethacin at 0.73 ± 0.07 mM, podophyllotoxin and kaempferol with higher EF values exerted stronger inhibitory effects with IC50 values at 0.36 ± 0.02 mM and 10.49 ± 0.61 mM, respectively. Additionally, the optimal binding sites and mode of action between bioactive ligands and multiple drug targets were determined by molecular docking. Wherein, isorhamnetin showed a stronger affinity to ACE2 with the binding energy of -5.72 kcal/mol and the IC50 value at 63.95 mM, lower than MLN-4760 (-4.27 kcal/mol and 738.62 mM). Conclusions: The integrative strategy combining multiple drug targets and bio-affinity ultrafiltration LC-MS in the present study showed very promising potential for the quick screening and identifying bioactive ligands in S. hexandrum for Topo I, Topo II, COX-2 and ACE2, and some bioactive compounds screened out from this work were verified with other in vitro assays, and even better than those positive drugs of interest. Based on these findings, we then first constructed an interacting network among multi-components and multi-targets. In this way, we showcased a quick and reliable experimental strategy for uncovering the underlying mechanism of the empirical traditional applications of S. hexandrum which could also provide valuable information for better understanding the therapeutic targets and therapeutic ligands of other herbal medicines.
Potential multiple bioactive components from Sinopodophyllum hexandrum explored by affinity ultrafiltration with four drug targets