Figure 8.

UO126 reduces EM evidence of AVs in MPP⁺-treated cells. SH-SY5Y cells were treated with buffer (A), MPP⁺ (B), or MPP⁺ in the presence of the MEK inhibitor UO126 (C) for 24 hours. Mitochondria (arrowheads) are readily identified in both control (A) and MPP⁺/UO126-treated (C) cells, but AVs (arrows) are most prominent in cells treated with MPP⁺ alone (B). Although AVs in MPP⁺-treated cells displayed multiple membrane layers and/or heterogeneous contents (B, arrows), cells cotreated with MPP⁺ and UO126 contained occasional round, uniformly dense structures (C, asterisks) the significance of which is unclear but could represent highly condensed AVs or early lysosomes. C: Cotreatment with UO126 reduced AV-like structures but did not prevent MPP⁺-induced mitochondrial swelling. Scale bar = 1 μm.