The effect of amyloid β (A β ) on phosphorylated p62 levels. (a) SH-SY5Y neuroblastoma cells were treated with Aβ40 or Aβ42, Baf or Epo. After 24 h, cells were harvested, lysed and analysed by immunoblotting. Epo increases the levels of total p62 and P-S349, whereas the P-S403 level is undetectable. In a sample treated with Baf, lipidated LC3 (LC3-II) is induced in a time-dependent manner, but signals for P-S349 and P-S403 are undetectable due to the low level of total p62. (b) A proteasomal activity assay confirms that Epo inhibits trypsin-like, chymotrypsin-like and caspase-like activities of the proteasome. Baf mildly inhibits these activities. However, Aβ40 and Aβ42 have no effect on proteasome activity and autophagic flux.