Effect of Rhodiola rosea L. Extract on Alzheimer's Disease-like Symptoms in Caenorhabditis elegans.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline, oxidative stress, and amyloid-beta accumulation. Natural products with antioxidant and stress-response-modulating properties are increasingly being investigated as candidate neuroprotective agents. In this study, we evaluated the effects of Rhodiola rosea L. extract, salidroside, and rosavin in Caenorhabditis elegans models of AD. Phenotypic, behavioral, biochemical, and molecular assays were used to assess locomotion, egg laying, chemotaxis, reactive oxygen species (ROS), gene expression, and amyloid-like aggregation. The extract and its related compounds improved locomotor performance, partially rescued reproductive and sensory defects, reduced ROS accumulation, modulated stress-response genes including skn-1/nrf2, daf-2, and sod-1, and decreased thioflavin-S-positive aggregates. Together, these findings support the potential neuroprotective effect of R. rosea extract and its key marker compounds, suggesting the involvement of conserved antioxidant pathways.