Effect of sHN and its derivatives on neuronal cell death by FAD genes. A, Effect of sHN and its derivatives on neuronal cell death induced by FAD-linked mutant APPs (A617G-APP and L648P-APP). F11 cells were transfected with or without either A617G-APP cDNA or L648P-APP cDNA and were treated with various concentrations of sHN (0, 10 pm, 100 pm, 1 nm, 10 nm, 100 nm, 1 μm, 10 μm, and 100 μm from left to right), sHNG (0, 10 pm, 100 pm, 1 nm, 10 nm, 100 nm, 1 μm, 10 μm, and 100 μm from left toright), and sHNA (0, 10 nm, 100 nm, 1 μm, 10 μm, and 100 μm from left to right). Seventy-two hours after transfection, cell mortality was similarly measured. As controls, cell mortality without transfection (no T) or with pcDNA transfection (vec) was measured in each experiment. B, Effect of sHN and its derivatives on neuronal cell death induced by FAD-linked mutant PS1s (A246E-PS1, L286V-PS1, C410Y-PS1, and H163R-PS1). Left, F11 cells were transfected with or without each mutant PS1 cDNA in pcDNA (pcDNA mutant PS1) and were treated with or without (1) 10 nm sHN (2), 10 μm sHN (3), 10 nm sHNG (4), or 10 μm sHNA (5). Seventy-two hours after transfection, cell mortality was similarly measured. As controls, cell mortality without transfection (no T) or with pcDNA transfection (vec) was measured in each experiment.Right, PS1 expression in the experiments shown in theleft panel. Seventy-two hours after transfection performed in the experiments shown in theleft panel, cell lysates were submitted to immunoblot analysis with anti-PS1 antibody [no T, no transfection; vec, pcDNA transfection instead of PS1 cDNAs; 1–5 correspond to those in the left panel (1, PS1 mutant transfection alone;2, PS1 mutant transfection in the presence of 10 nm sHN; 3, PS1 mutant transfection in the presence of 10 μm sHN; 4, PS1 mutant transfection in the presence of 10 nm sHNG; and5, PS1 mutant transfection in the presence of 10 μm sHNA)]. The top bands (∼50 kDa) correspond to the holoprotein of endogenous or mutant PS1s, and thebottom bands (∼30 kDa) correspond to the N-terminal fragments of the cognate PS1s. ** and * indicate significant and not significant versus relevant FAD gene transfection, respectively.