Comprehensive analysis of <i>Salvia uliginosa</i> extract: HPLC-MS, GC-MS and evaluation of antioxidant and neuroprotective effects

Alzheimer's disease (AD) poses an increasing threat to human health, with limited treatment options emphasising the need for low-toxicity, and widely accessible natural drugs. <i>Salvia uliginosa</i>, a traditional Brazilian medicinal, was analysed using HPLC-MS and GC-MS to identify chemical components. The study investigated the neuroprotective effects and mechanisms of <i>S.uliginosa</i> extract (SUPE) in <i>C.elegans</i> AD model. Results showed that SUPE significantly delayed <i>β</i>-amyloid (A<i>β</i>)-induced paralysis and deposition, reduced A<i>β</i> neurotoxicity, and extended nematode lifespan. SUPE also enhanced resistance to hydrogen peroxide and heat stress, decreased reactive oxygen species and malondialdehyde accumulation, and increased superoxide dismutase and catalase activity. Transcriptomic profiling revealed 1,370 differentially expressed genes, primarily enriched in longevity-regulating pathways and sterol biosynthesis pathways. RNA interference experiments confirmed that SUPE upregulates <i>hsp-16.2</i> and downregulates <i>srlf-36</i> gene expression. These findings underscore <i>S. uliginosa</i> as a promising natural source for anti-AD therapeutics and provide new insights into its potential clinical applications.