Phillyrin: A potential therapeutic agent for osteoarthritis via modulation of NF-κB and Nrf2 signaling pathways

•The treatment of osteoarthritis is mainly based on palliative care.•Before the experiment, network pharmacology and molecular docking were used to predict the pathway and target of phillyrin.•Phillyrin inhibits IL-1β-induced extracellular matrix degradation.•Phillyrin inhibits osteoarthritis by regulating nrf-2/NF-κB.•Phillyrin can be used as a potential treatment for osteoarthritis. Osteoarthritis (OA) is the predominant cause of disability among elderly people worldwide and is characterized by cartilage degeneration and excessive bone formation. Phillyrin, derived from forsythia, is a key extract renowned for its pronounced antibacterial and anti-inflammatory effects. Forsythia, deeply integrated into traditional Oriental medicine, has historically been utilized for its various pharmacological effects, including antibacterial, anti-inflammatory, and hepato-protective properties. Nevertheless, the anti-inflammatory impact of phillyrin on the progression of osteoarthritis remains enigmatic. The objective of this research was to assess the anti-inflammatory and anti-aging properties of phillyrin in mouse chondrocytes induced by IL-1β, as well as to elucidate the fundamental mechanisms underlying the phenomenon at play. Additionally, the investigation extends to observing the impact of phillyrin by establishing a murine osteoarthritic model. The ultimate goal was to identify phillyrin as a potential antiosteoarthritic agent. This investigation employs a multifaceted approach. Initially, key action targets of phillyrin, along with its probable action pathways, were identified by molecular docking and network pharmacological techniques. These findings were subsequently confirmed through both in vivo and in vitro studies. Network pharmacological analysis revealed NFE2L2 (NRF2), NFKB1, TLR4, and SERPING1 as pivotal candidate targets for the treatment of osteoarthritis with phillyrin. Molecular docking revealed hydrogen bond interactions between phillyrin and Arg415, Arg483, Ser508, and Asn387 on the Nrf2 receptor, while electrostatic interactions occurred with residues Arg415 and Arg380. Experiments conducted in vitro indicated that phillyrin preconditioning hindered the IL-1β-induced expression of proinflammatory factors which included TNF-α, COX-2, IL-6, and iNOS. Furthermore, phillyrin counteracts the IL-1β-induced degradation of aggrecan and collagen II within the extracellular matrix (ECM). This protective action is caused by the inhibition of the NF-κB pa