Figure 11

IETD-fmk inhibits microglial activation induced by neuromelanin. Phase contrast micrograph of BV2 cultures under different treatments. (A) Control cells, showing the round morphology characterizing resting microglial cells in culture. (B) The caspase-8 inhibitor IETD-fmk showed no effect on resting cells. (C) Lipopolysaccharide, used as a positive control, induced clear changes in the cells morphology (white arrowheads), which lost their resting round shape. (D) IETD-fmk reduced the activation induced by lipopolysaccharide in the BV2 cells. (E) Neuromelanin (black deposits marked by black arrows) induced a clear activation of BV2 cells, in a similar way to the proinflammogen lipopolysaccharide. (F) Inhibition of caspase-8 prevented the activation of BV2 cells induced by neuromelanin. Round resting cells in close contact with neuromelanin can be seen (white arrows). Scale bar, 50 μm. LPS, lipopolysaccharide; NM, neuromelanin.