Activation of Delta-Opioid Receptor Protects ARPE19 Cells against Oxygen-Glucose Deprivation/Reoxygenation-Induced Necroptosis and Apoptosis by Inhibiting the Release of TNF-α

Figure 5

The DOR agonist TAN-67 suppresses TNF-α levels and the expression of necroptotic and apoptotic proteins in ARPE19 cells induced by OGD24/R36. (a) TNF-α levels in cell lysates from each group were measured by ELISA (n = 5 per group). (b–c) The level of DOR expression was examined by Western blotting, and the density values were normalized to the levels of β-actin (n = 3 per group). (d–k) Western blot showing the activation or total abundance of p-RIP1 (RIP1), p-RIP3 (RIP3), p-MLKL (MLKL), and cleaved Caspase-3 (Caspase-3) as indicated (n = 3 per group). P-RIP1, phosphorylated RIP1; p-RIP3, phosphorylated RIP3; p-MLKL, phosphorylated MLKL. Data are presented as means ± SEM, and group differences were analyzed by one-way ANOVA with Dunnett’s post hoc test. ^##, ^### compared with the control group; , , , compared with the OGD24/R36 group.

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