Dual anthelmintic and hepatoprotective potential of Populus tremula bark polysaccharide complex in vitro

Opisthorchiasis, caused by the liver fluke Opisthorchis felineus, remains a significant public health problem in Western Siberia and other parts of Eurasia. The present study investigated the anthelmintic and hepatoprotective properties of a polysaccharide complex (PC) extracted from Populus tremula bark. Anthelmintic activity was assessed in vitro against O. felineus worms using motility scores, MTS viability assay, and propidium iodide (PI) staining. Hepatoprotective potential was evaluated in HepG2 cells using lipopolysaccharide/interferon-g (LPS/IFN-g) induced inflammation and free fatty acid (FFA) induced lipotoxicity models; reactive oxygen species (ROS), reduced glutathione (GSH), and intracellular lipid content were measured fluorimetrically. Antioxidant activity was further characterised by DPPH radical scavenging and ferrous ion chelating assays. PC significantly reduced worm motility and viability (calculated motility index decreased by approximately 45%, from 3.80 to 2.10), and induced focal tegumental PI accumulation, consistent with surface damage. In the LPS/IFN-g model, PC at 125 µg/mL decreased ROS by 14% (p=0.001) and partially restored GSH content by 25% (p=0.016). In FFA treated cells, the same concentration attenuated ROS by 15.5% (p=0.001) and reduced lipid accumulation by 22.8% (p=0.008). PC did not affect HepG2 viability. The complex demonstrated modest DPPH radicalscavenging activity (33.6% at 200 µg/mL) and a pronounced Fe2+ chelating capacity (24.70±2.63 mg EDTA equivalents/g). These first initial in vitro findings identify P. tremula bark PC as a candidate dualaction agent for treating of opisthorchiasis, combining direct anthelmintic activity with multi-targeted hepatoprotective effects that warrant confirmation in further mechanistic and in vivo studies.