Tribulus terrestris Ameliorates Oxidative Stress-Induced ARPE-19 Cell Injury through the PI3K/Akt-Nrf2 Signaling Pathway

Figure 3

Effects of EE-TT on the protein expression levels of Bcl-2, Bax, caspase-3, and caspase-9 in H₂O₂-treated ARPE-19 cells. ARPE-19 cells were pretreated with or without 1 mM H₂O₂ for 24 h, followed by a 24 h exposure to ethanol extracts of Tribulus terrestris (EE-TT) (100 or 200 μg/mL). (a) The cell lysates of control (nontreatment), H₂O₂-treated alone, or H₂O₂ plus EE-TT-treated samples were analyzed by Western blot assay with the antibodies of Bcl-2, Bax, cleaved caspase-3, cleaved caspase-9, and β-actin, respectively. Quantification data of these protein expression levels were measured and normalized to β-actin expression levels. The fold changes vs. control sample (nontreatment) were presented in the bar graph from (b–e), respectively. Data are shown as , , , vs. the nontreatment control sample; ^#, ^##, ^### vs. the sample with H₂O₂ treatment alone, .

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