Highlights

A novel series of chalcone derivatives were synthesized as Nrf2 activators.

Compound 20a increases antioxidant enzyme expression by nuclear translocation of Nrf2.

20a suppresses reactive oxygen species against oxidative stress in microglia.

20a increases expression level and activity of superoxide dismutase in vitro and in vivo.

20a restores scopolamine-induced memory impairment in mice.

Abstract

Alzheimer’s disease is a common neurodegenerative disease characterized by progressive degeneration and neuronal cell death, resulting in neural network dysfunction. As the underlying mechanisms, oxidative damage and neuroinflammation have been reported to contribute to the onset and deterioration of Alzheimer’s disease. The nuclear factor E2-related factor 2-antioxidant responsive element signaling pathway is a pivotal cellular defense mechanism against oxidative stress. Nrf2, a transcription factor, regulates the cellular redox balance and is primarily involved in anti-inflammatory responses. In this study, we synthesized novel chalcone derivatives and found a highly potent Nrf2 activator, compound 20a. Compound 20a confirmed to activate Nrf2 and induce expression of the Nrf2-dependent enzymes HO-1 and GCLC at both mRNA and protein levels. It also suppressed the production of nitric oxide and downregulated inflammatory mediators in BV-2 microglial cells. We found that compound 20a effectively increased the expression level and the activity of superoxide dismutase in both BV-2 microglial cells and brain hippocampus region of the scopolamine-induced mouse model. In addition, compound 20a effectively recovered the learning and memory impairment in a scopolamine-induced mouse model.