Curculigoside, a traditional Chinese medicine monomer, ameliorates oxidative stress in Alzheimer's disease mouse model via suppressing ferroptosis

Alzheimer's disease (AD) is a neurodegenerative disorder where oxidative stress, induced by ferroptosis, has been linked to neuronal damage and cognitive deficits. The objective of this study is to investigate if the potential therapeutic agent, Curculigoside (CUR), could ameliorate AD by inhibiting ferroptosis. The potential therapeutic targets, such as GPX4 and SLC7A11, were identified using weighted gene co-expression network analysis (WGCNA). Concurrently, CUR was also screened against these potential targets using various analytical methods. For the in vivo studies, intragastric administration of CUR significantly ameliorated cognitive impairment in AD model mice induced by scopolamine and okadaic acid (OA). In vitro, CUR protected neuronal cells by altering the levels of ferroptosis-related specific markers in OA and scopolamine-induced neurotoxicity. The administration of CUR through intragastric route significantly reduced the levels of AD-promoting factors (such as Aβ1-42 , p-tau) and ferroptosis-promoting factors in the hippocampus and cortex of AD mice. Furthermore, CUR up-regulated the expression of GPX4 and decreased the expression of SLC7A11 in the ferroptosis signaling pathway, thereby increasing the ratio of glutathione (GSH)/oxidized glutathione (GSSG) in vivo and vitro. In conclusion, the cumulative results suggest that the natural compound CUR may serve as a promising therapeutic agent to ameliorate AD by inhibiting ferroptosis.