Harpagophytum procumbens Inhibits Iron Overload-Induced Oxidative Stress through Activation of Nrf2 Signaling in a Rat Model of Lumbar Spinal Stenosis

Figure 1

Harpagophytum procumbens (HP) attenuates FeSO₄-induced neurotoxicity in primary spinal cord neurons. (a) Schematic illustration of the experimental protocol of primary spinal cord neurons with HP posttreatment. (b and c) CCK-8 results of spinal cord neurons treated with various concentrations of HP for 24 h, without and with exposure to 50 μM FeSO₄. (d) Quantification of the number of live and dead cells for the neurotoxicity assay. (e) Cell viability was imaged with confocal microscopy using a live/dead imaging assay kit (live cells, green; dead cells, red). White  μm. (f) The percentage of PI-positive neurons from live cell imaging over a 48 h period, with images taken every 30 min. (g) Flow cytometric quantification of necrotic cells (Annexin V-negative/PI-positive), challenged with 50 μM FeSO₄. (h) Representative flow cytometric dot plots showing Annexin V (-axis) and PI (-axis) analysis for cell death type in spinal cord neurons. Data are expressed as the . Significant differences are indicated as ^#### vs. the blank group, , , , and vs. the FeSO₄ group, according to one-way analysis of variance with Tukey’s post hoc test.

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