Safflower Yellow Alleviates Cognitive Impairment in Mice by Modulating Cholinergic System Function, Oxidative Stress, and CREB/BDNF/TrkB Signaling Pathway.

Ethnopharmacological relevance: Carthamus tinctorius L. (Safflower) was believed to have multiple benefits, including antioxidant effects, enhanced learning and memory, and improving neuronal injury. Safflower Yellow(SY) are the main active ingredients of Safflower, displays strong pharmacological potential treatment of Alzheimer's disease(AD). However, its effect on memory impairments remains insufficiently investigated.

Aim of the study: The study aims to investigate the effects of SY on cognitive functions in memory impairments model and to explore the mechanism of its action.

Materials and methods: We utilized the Morris Water Maze, Step-Through Test, Step-Down Test to assess the potential of SY in ameliorating learning and memory dysfunction caused by SCOP, NaNO₂ and ethanol in mice. Bioinformatic analysis and molecular biological approaches were used to study the related mechanisms of SY on anti-memory impairments.

Results: The results of the Morris Water Test suggested that SY could shorten the escape latency and the time of the first crossing platform in the mice with memory acquisition and memory consolidation impairments, and increase the platform crossing times. The results of the Step-Though test and Step-Down test showed that the escape latency in the mice was prolonged and the number of errors was reduced after SY treatment. ELISA experiments indicated that SY decreased the AChE activities, increased the ChAT activities, and modulated oxidative stress markers (SOD, MDA, and GSH-PX) in scopolamine-induced mice. Western Blot and Nissl staining showed that SY could activated BDNF/TrkB/CREB signaling pathway and reduced neuronal damage.

Conclusion: The findings present that SY can restore the function of the cholinergic system, inhibit oxidative stress, regulate the expression of upstream and downstream proteins in the CREB/BDNF/TrkB pathway, and alleviate brain tissue damage to improve memory impairment in mice.