Mechanistic Elucidation of green seaweed compounds in orthodontic relapse management via RANKL/TNF-α-mediated ROS/Keap1/Nrf2 signaling: In silico and Ex Vivo studies

Orthodontic relapse, the return to a pre-treatment position after orthodontic correction, is driven by the RANKL/
TNF-α-mediated ROS/Keap1/Nrf2 signaling axis. This mechanism triggers aseptic inflammation and oxidative
stress, influencing bone resorption and formation. Antioxidants can mitigate oxidative stress, potentially
improving post-orthodontic outcomes. This study explores the efficacy of antioxidant compounds derived from
green seaweed/algae in managing orthodontic relapse. Green seaweed/algae extracts were prepared via sonication, and bioactive compounds were identified using ultra-performance liquid chromatography-electrospray
ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) analysis. Compounds underwent bioactivity prediction, toxicity assessment, and drug-likeness evaluation, revealing significant therapeutic potential. Network
pharmacology and molecular docking identified key proteins associated with orthodontic relapse, including IL1β, STAT3, ESR1, MAPK1, JAK2, and HMOX1. Molecular docking simulations indicated favorable binding energies for green seaweed compounds, particularly the alkaloids adenosine (ΔG − 6.9 to − 7.3 kcal/mol) and
lycopodine (ΔG − 6.3 to − 8.5 kcal/mol), against targeted proteins, matching or outperforming standard drugs
such as s-ibuprofen (ΔG − 6.7 kcal/mol). In vitro assays confirmed the antioxidant activity of these compounds,
with EC50 dose of 52.2–54.2 μg/mL for ABTS radical scavenging capacities. Protein expression analysis in tibialfemoral bone marrow cells further demonstrated the potential of green seaweed/algae compounds to suppress
osteoclastogenesis by modulating the RANKL/TNF-α-mediated ROS/Keap1/Nrf2 pathway. This research highlights the promise of green seaweed-derived antioxidants in reducing oxidative stress and managing orthodontic
relapse, providing a foundation for future therapeutic developments.