Fig. 5

27-OHC inhibits proteasomal function and reduces HSP70 levels. 27-OHC and the proteasomal inhibitor MG132 significantly decrease Caspase-Like Proteasomal Activity (a), Chymotrypsin-Like Proteasomal Activity (b), and Trypsin-Like Proteasomal Activity (c). Representative western blot (d) and optical density (e) of α-syn. Western blots are expressed as fold change over β-Actin. 27-OHC and MG132 significantly increase the amount of α-syn protein. Representative western blot (f) and optical density (g) of HSP70 showing that while 27-OHC reduces HSP70 levels, treatment with MG132 dramatically increases HSP70 protein levels. Data are expressed as individual values with mean ± SEM and includes determinations made in one experiment with (n = 3) for the proteasomal assays and two separate experiments including (n = 3) and three technical replicates for the western blots. *p < 0.05, **p < 0.01, ***p < 0.001 versus control. ^†p < 0.05, ^†††p < 0.001 MG132 versus 27-OHC