Fig. 3

MFN1 and MFN2 expression in grade III disc NPCs. (a) Immunofluorescence showing MFN1 (red), actin (phalloidin, green), and nuclei (DAPI, blue) under different conditions: TNF-α (−), TNF-α (+, 10 ng mL⁻¹), TNF-α + Vit E(50 µM), and TNF-α + SPN(25 µg mL⁻¹). Antioxidant treatments reduced MFN1 expression, with Vit E showing greater efficacy. (b) Immunofluorescence staining for MFN2 (red), actin (green), and nuclei (blue) under the same conditions. Similar to MFN1, antioxidants decreased MFN2 expression, with Vit E being more effective. Control, TNF-α-induced inflammation, anti-inflammation by Vit E, and anti-inflammation by SPN groups were compared. MFN, Quantification of MFN1 and MFN2 fluorescence intensity normalised to DAPI-positive cell count. Data represent mean ± SD of three independent experiments performed in triplicate (n = 9), All images were captured in a single confocal session with identical laser and exposure settings. Scale bars = 50 µm. : mitofusin, TNF-α: tumor necrosis factor-α, Vit E: vitamin E, SPN: saponin, NPC: nucleus pulposus cell.