Research Paper Volume 13, Issue 13 pp 17097—17117

Inhibition of heat shock proteins increases autophagosome formation, and reduces the expression of APP, Tau, SOD1 G93A and TDP-43

GRP78, HSP90 and HSP70 play important roles in maintaining the stability of Tau and APP. (A) HCT116 ATG16L1 T300 cells were transfected with an empty vector plasmid (CMV) or with plasmids to express GRP78, HSP70 or HSP90, and were co-transfected to express either Tau or APP. Twenty-four h after transfection cells were treated with vehicle control, AR12 (2 μM), neratinib (50 nM) or the drugs in combination for 24h. Cells were fixed in place and the expression of Tau and APP determined (n = 3 +/-SD). # p B) HCT116 ATG16L1 T300 cells were transfected with a scrambled control siRNA (siSCR) or with siRNA molecules to knock down expression of GRP78, HSP70 or HSP90, as indicated in the panel. In parallel, cells were transfected to express either Tau or APP. Twenty-four h after transfection, cells were fixed in place and the expression of Tau and APP determined (n = 3 +/-SD). Vehicle control transfected with a scrambled siRNA is defined at 100%. * p

Figure 6. GRP78, HSP90 and HSP70 play important roles in maintaining the stability of Tau and APP. (A) HCT116 ATG16L1 T300 cells were transfected with an empty vector plasmid (CMV) or with plasmids to express GRP78, HSP70 or HSP90, and were co-transfected to express either Tau or APP. Twenty-four h after transfection cells were treated with vehicle control, AR12 (2 μM), neratinib (50 nM) or the drugs in combination for 24h. Cells were fixed in place and the expression of Tau and APP determined (n = 3 +/-SD). # p < 0.05 greater than corresponding value in CMV transfected cells; * p < 0.05 less than corresponding value in corresponding vehicle control cells; ** p < 0.05 less than corresponding AR12 value. (B) HCT116 ATG16L1 T300 cells were transfected with a scrambled control siRNA (siSCR) or with siRNA molecules to knock down expression of GRP78, HSP70 or HSP90, as indicated in the panel. In parallel, cells were transfected to express either Tau or APP. Twenty-four h after transfection, cells were fixed in place and the expression of Tau and APP determined (n = 3 +/-SD). Vehicle control transfected with a scrambled siRNA is defined at 100%. * p < 0.05 less than corresponding value in vehicle control cells; ** p < 0.05 less than corresponding AR12 value; p < 0.05 less than corresponding value in siSCR cells; † p < 0.05 greater than corresponding value in siSCR cells.