Fig. 5. Urolithin A (UA) attenuated H₂O₂-induced SK-N-MC cell death by modulating the p38 MAPK signaling pathway. (A) The cells pretreated with UA for 6 h, and then treated with 300 µM H₂O₂ for 18 h.

The protein levels of phosphorylated p38, total p38, and GAPDH were determined by Western blotting and normalized to the levels of GAPDH. (B) The cells were pretreated with SB206580 (p38 MAPK inhibitor) for 1 h, treated 5 µM UA for 6 h, and then treated with 300 µM H₂O₂ for 18 h. The cell viability was measured using the CCK-8 assay. The results are expressed as mean ± SD. Different letters indicate a significant difference according to analysis of variance (P < 0.05).