Anandamide Protects HT22 Cells Exposed to Hydrogen Peroxide by Inhibiting CB1 Receptor-Mediated Type 2 NADPH Oxidase

Figure 4

AEA protected HT22 cells exposed to H₂O₂ via CB1. (a) CB1 antagonist AM251 reversed AEA-induced protection on cell metabolic activity (𝑛=8). (b) AM251 reversed AEA-induced protection on LDH release (𝑛=6). (c) AM251 reversed AEA-induced reduction of cleaved caspase-3 expression (𝑛=4). (d)–(h) Apoptotic rates assessed by flow cytometry. (d) Control cells cultured in drug-free medium. (e) Cells exposed to 200 μM H₂O₂ for 3 h. (f) Cells exposed to 10 μM AEA plus 200 μM H₂O₂ for 3 h. (g) Cells exposed to 10 μM AEA plus 10 μM AM251 in the presence of 200 μM H₂O₂ for 3 h. (h) Cells exposed to CB1 antagonist AM251 of 10 μM plus 200 μM H₂O₂ for 3 h. (i) Statistical results of (c)–(g). Results are expressed as means ± SD (𝑛=4). ^∗𝑃<0.05 versus the control (no H₂O₂, no AEA, and no AM251), ^#𝑃<0.05 versus the cells exposed to H₂O₂ alone, and ^∧𝑃<0.05 versus the cells exposed to AEA plus H₂O₂.

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