P09-53 Toxicity and Protective Effects of Plant Extracts from the Choco Biogeographic Region (Colombia) Against Amyloid-β-Induced Toxicity in Caenorhabditis elegans

The Chocó biogeographic region is one of the most biodiverse areas on the planet, with an extraordinary variety of plant species traditionally used to treat numerous diseases, including those affecting the nervous system. However, many of these species and their compounds have not been thoroughly evaluated in terms of toxicological safety and biological activity. To assess the biological activity of hydroalcoholic extracts obtained from plant species of the Chocó department (Colombia), using the C. elegans biological model, specifically the N2 strain and a transgenic model that expresses the β-amyloid peptide in the muscle of the worms. L4 larvae of the wild-type N2 strain were exposed to five extract concentrations (50–2500 μg/mL) to evaluate lethality and impact on locomotion. Three extracts showing low toxicity and minimal effects on locomotion, and with ethnobotanical and scientific reports for neurological symptom management, were selected for the neuroprotection model. L1 larvae of the CL4176 strain [smg-1 (myo-3/β-amyloid 1–42/letUTR)+pRF4] were incubated for 48 hours at 15°C with each extract at a concentration of 500 μg/mL, and DMSO was used as a negative control. Subsequently, worms were washed and transferred to fresh plates at 25°C (the temperature at which the β-amyloid peptide is expressed), and their movement was monitored every 24 hours until complete paralysis occurred in the control group (DMSO). Of the ten extracts evaluated, only the extract of Satureja brownei (Poleo) showed lethality above 95% at concentrations of 1000 μg/mL and higher. The remaining extracts showed low lethality, below 10%. The extracts of Petiveria alliacea , Mimosa pudica , and Tagetes patula not only exhibited low lethality but also demonstrated a significant reduction in paralysis after 72 hours compared to the control, particularly the extract of Mimosa pudica (DM-P-HT), which maintained a higher proportion of mobile worms (p<0.05). The results suggest that the evaluated extracts may exert a protective effect against β-amyloid-induced toxicity in Caenorhabditis elegans , reducing paralysis in an experimental model of Alzheimer's disease. These preliminary findings support the neuroprotective potential of the extracts and justify further investigation in more complex models of neurodegeneration. Funding: Minciencias (Call 934/2023, Contract No.112721- 420-2023, National post-doctoral scholarships).