Luteolin ameliorates necroptosis in Glucocorticoid-induced osteonecrosis of the femoral head via RIPK1/RIPK3/MLKL pathway based on network pharmacology analysis.

Glucocorticoid-induced osteonecrosis of the femoral head (GIONFH) is deeply relevant to damage and dysfunction of bone microvascular endothelial cells (BMECs). Recently, necroptosis, a newly programmed cell death with necrotic appearance, has garnered increasing attention. Luteolin, a flavonoid compound derived from Rhizoma Drynariae, has numerous pharmacological properties. However, the effect of Luteolin on BMECs in GIONFH through the necroptosis pathway has not been extensively investigated. Based on network pharmacology analysis, 23 genes were identified as potential targets for the therapeutic effect of Luteolin in GIONFH via the necroptosis pathway, with RIPK1, RIPK3, and MLKL being the hub genes. Immunofluorescence staining results revealed high expression of vWF and CD31 in BMECs. In vitro experiments showed that incubation with dexamethasone led to reduced proliferation, migration, angiogenesis ability, and increased necroptosis of BMECs. However, pretreatment with Luteolin attenuated this effect. Based on molecular docking analysis, Luteolin exhibited strong binding affinity with MLKL, RIPK1, and RIPK3. Western blotting was utilized to detect the expression of p-MLKL, MLKL, p-RIPK3, RIPK3, p-RIPK1, and RIPK1. Intervention with dexamethasone resulted in a significant increase in the p-RIPK1/RIPK1 ratio, but the effects of dexamethasone were effectively counteracted by Luteolin. Similar findings were observed for the p-RIPK3/RIPK3 ratio and the p-MLKL/MLKL ratio, as anticipated. Therefore, this study demonstrates that Luteolin can reduce dexamethasone-induced necroptosis in BMECs via the RIPK1/RIPK3/MLKL pathway. These findings provide new insights into the mechanisms underlying the therapeutic effects of Luteolin in GIONFH treatment. Additionally, inhibiting necroptosis could be a promising novel approach for GIONFH therapy.