Figure 6.

Small molecules prevent proteasome dysfunction by intracellular α-synuclein. SH-SY5Y cells were transfected with GFP-CL1 alone or both GFP-CL1 and α-synuclein. Compounds (final 40 μM) were added 2 h after transfection. Cells were harvested after a 72-h incubation and analyzed by immunoblotting (A) and confocal microscopy (B). Immunoblot analyses of Tris-soluble (lower panels) and SDS-soluble fractions (upper panels) were performed using anti-GFP (upper panels) or anti-Syn102 (lower panels) antibodies. The decreased GFP-CL1 level in transfected cells treated with compound B or C, as compared with that of transfected cells treated with vehicle alone (DMSO), indicated that compound B or C, but not compound A, rescued cells from proteasome impairment by expression of α-synuclein.