The mRNA and protein levels of amyloid precursor protein, amyloid-β40 and amyloid-β42 were evaluated by quantitative real-time polymerase chain reaction, western blot assays and enzyme-linked immunosorbent assays. swAPP695-HEK293 cells were transfected with miR-15b-5p mimic, or treated with 1 μM curcumin 24 hours before miR-15b-5p inhibitor transfection.