Antioxidant and Neuroprotective Activities of Gastrodia elata Blume Aqueous Extract in Caenorhabditis elegans

Gastrodia elata Blume (GE) is recognized as a plant with both nutritional and medicinal properties, reported to exhibit neuroprotective and antioxidant effects, which contribute to its widespread use in various fields. However, the mechanisms underlying these effects remain insufficiently understood. In this study, we utilized ultrasound-assisted extraction to isolate water-soluble substances from GE and conducted in vitro antioxidant assays to evaluate the capacity of Gastrodia elata water extract (GWE) to scavenge DPPH and ABTS free radicals. Further investigation into the antioxidant and neuroprotective potential of GWE was conducted through in vivo studies using Caenorhabditis elegans ( C. elegans ). It was observed that GWE at concentrations of 50, 100, and 200 μg/mL enhanced locomotion and antistress capabilities while significantly reducing levels of H 2 O 2 , O 2 − , lipofuscin, and reactive oxygen species (ROS). Concurrently, glutathione levels were significantly elevated. GWE supplementation stimulated the activity of serotonergic, dopaminergic, and GABAergic neurons, thereby improving locomotor abilities, including body bends, head thrashing, foraging behavior, and chemotaxis. Notably, significant increases in the relative concentrations of gamma-aminobutyric acid (GABA) and serotonin were also observed. Further research demonstrated that GWE treatment elevated the mRNA levels of genes associated with GABA and serotonin in the treated nematodes, specifically the unc-25 , unc-46 , unc-49 , unc-47 , tph-1 , mod-1 , mod-5 , cat-4 , cat-1 , and exp-1 genes. Additionally, GWE treatment significantly enhanced the expression of the daf-16 , sod-3 , skn-1 , hsf-1 , and hsp-16.2 genes. GWE also promoted the translocation of DAF-16 into the nucleus, upregulated the expression of SOD-3::GFP, and downregulated the expression of gst-4 and GST-4::GFP. Spearman’s correlation analysis revealed a significant positive association between the daf-16 , hsp-16.2 , cat-1 , unc-46 , unc-47 , and mod-1 genes and the levels of serotonin, GABA, and locomotor behaviors. This study enhances our understanding of the mechanisms through which GWE exhibits neuroprotective and antioxidant properties, thereby elucidating the health benefits of GE for living organisms.