Tocopherol Inhibits BMSC Ferroptosis Through the Mapk/Nrf2 Signalling Pathway to Delay the Progression of Osteonecrosis of the Femoral Head

Osteonecrosis of the femoral head (ONFH) is a serious bone health issue, with oxidative stress considered a key factor. Research showed that oxidative stress accelerates the progression of ONFH by inducing ferroptosis in BMSCs, involving lipid peroxidation of polyunsaturated fatty acid phospholipids and membrane structural damage. As a potent antioxidant, tocopherol can terminate the propagation of lipid peroxidation radicals and limit ROS damage to cell membranes, potentially helping to inhibit ferroptosis. However, there is currently no research proving whether tocopherol can effectively delay the progression of ONFH. mIHC analysis of the expression changes of CD73, CD105, GPX4, and MAPK in osteonecrotic tissue. CCK-8 assays demonstrated that tocopherol significantly reduced cell death induced by TBHP, with necroptosis inhibitor (Nec-1), apoptosis inhibitor (Z-VAD), and ferroptosis inhibitor (Fer-1) used to exclude other forms of cell death. Detection of malondialdehyde (MDA). WB analysis showed that tocopherol treatment affectd ferroptosis-related markers and MAPK expression changes. MRI and Micro-CT analyses revealed microstructural changes in the osteonecrotic regions. This study used mIHC analysis to examine osteonecrotic regions in patients with hormonal, alcoholic, and idiopathic femoral head necrosis, revealing decreased CD73, CD105, GPX4 expression and increased MAPK expression (Figure 1 A-B). CCK-8 assays showed that tocopherol significantly improved cell survival under TBHP-induced stress, unlike necroptosis inhibitor (Nec-1) and apoptosis inhibitor (Z-VAD) (Figure 2 A-B). Tocopherol treatment reduced malondialdehyde (MDA) levels. Western blot analysis indicated that tocopherol upregulated GPX4 and SLC7A11, inhibits PTGS2 expression, and decreased phosphorylation levels of p-P38, p-ERK, and p-JNK MRI and Micro-CT analyses suggested that tocopherol treatment partially repaired femoral head necrosis, reducing necrotic volume. Quantitative analysis showed significant reductions in BV, BV/TV, Tb.N, and Tb.Th in necrotic regions compared to control rats, while Tb.Sp and ON.V increased (Figure 3 A-B). Overall, tocopherol effectively protectd cells through its antioxidant properties and modulation of key signaling pathways, providing a new potential strategy for treating femoral head necrosis. Oxidative stress is closely related to ferroptosis and represents an important area of research in ONFH. This study confirmed ferroptosis in ONFH at both the tissue and cellular levels and evaluated the therapeutic potential of tocopherol. Pre-treatment of BMSCs with tocopherol significantly reduced ferroptosis. Tocopherol treatment significantly improved osteonecrosis of the femoral head in a mouse model, suggesting that targeting ferroptosis may represent a novel therapeutic strategy. However, the efficacy of tocopherol in humans still requires further validation. For any figures or tables, please contact the authors directly.