Alzheimer's disease (AD) is an age-related neurodegenerative disease that is characterized by irreversible memory loss and cognitive decline. The deposition of amyloid-β (Aβ), especially aggregation-prone Aβ42, is considered to be an early event preceding neurodegeneration in AD. Sirtuins (SIRT1-7 in mammals) are nicotinamide adenine dinucleotide-dependent lysine deacetylases/deacylases, and several sirtuins play important roles in AD. However, the involvement of SIRT7 in AD pathogenesis is not known. Here, we demonstrate that SIRT7 mRNA expression is increased in the cortex, entorhinal cortex, and prefrontal cortex of AD patients. We also found that Aβ42 treatment rapidly increased NADPH oxidase 4 (NOX4) expression at the post-transcriptional level, and induced reactive oxygen species (ROS) production and apoptosis in neuronal SH-SY5Y cells. In contrast, SIRT7 knockdown inhibited Aβ42-induced ROS production and apoptosis by suppressing the upregulation of NOX4. Collectively, these findings suggest that the inhibition of SIRT7 may play a beneficial role in AD pathogenesis through the regulation of ROS production.
Keywords: Alzheimer’s disease; NADPH oxidase; SIRT7; amyloid-β; apoptosis; reactive oxygen species.