ROS-Mediated Enamel Formation Disturbance Characterized by Alternative Cervical Loop Cell Proliferation and Downregulation of RhoA/ROCK in Ameloblasts

Figure 4

H₂O₂-induced oxidative stress exhibited dual effects on cervical loop stem cell proliferation and migration depending on the concentration of ROS. (a) The cell morphology changed under high concentration of H₂O₂ (100 μM and 200 μM). (b, c) The intracellular ROS concentration increased to approximately 2-2.5 times the normal concentration under 10 μM-25 μM H₂O₂. The intracellular ROS concentration increased to approximately 5-7 times the normal one under 50 μM, 100 μM, and 200 μM H₂O₂. (d, e) 10 μM-25 μM H₂O₂ promoted proliferation while 50 μM, 100 μM, and 200 μM H₂O₂ inhibited proliferation. 25 μM H₂O₂ had the most obvious promoting effect. (f) 5 μM and 10 μM H₂O₂ promoted the differentiation and mineralization of incisor cervical loop epithelial stem cells, while 50 μM and 100 μM H₂O₂ had a significant inhibitory effect. Scale bars: (a, f) 200 μm, (b, e) 100 μm, and (a) 200 μm. Data are shown as . , , and .

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