Bibliographic
Alzheimer’s disease neuropathology is characterized by β-amyloid plaques and neurofibrillary tangles. Inhibition of β-amyloid accumulation may be essential for effective therapy in Alzheimer’s disease. In this study we have treated transgenic mice carrying the Swedish mutation of human amyloid precursor protein [Tg(Hu.APP695.K670N-M671L)2576], which develop brain β-amyloid deposits, with nicotine in drinking fluid (200 lg/mL) from 9–14.5 months of age (5.5 months). A significant reduction in amyloid β peptide 1–42 positive plaques by more than 80% (p < 0.03) was observed in the brains of nicotine treated compared to sucrose treated transgenic mice. In addition, there was a selective reduction in extractable amyloid β peptides in nicotine treated mice; cortical insoluble 1–40 and 1–42 peptide levels were lower by 48 and 60%, respectively (p < 0.005), whilst there was no significant change in soluble 1–40 or 1–42 levels. The expression of glial fibrillary acidic protein was not affected by nicotine treatment. These results indicate that nicotine may effectively reduce amyloid β peptide aggregation in brain and that nicotinic drug treatment may be a novel protective therapy in Alzheimer’s disease.