Antihelminthic effect of thymoquinone against biliary amphistome, Gigantocotyleexplanatum

Recent research on the emergence of parasitic resistance to commonly prescribed anthelmintics has sparked a greater interest in finding novel therapeutic molecules, including those derived from plants. The use of medicinal plants and their derivatives has been viewed as an alternative source of anti-parasitic compounds and as being safe in comparison to synthetic medications due to the absence of adverse effects, ease of accessibility, and little to no expense. Consequently, in the current study, thymoquinone (TQ), an active component of Nigella sativa (Black cumin), has been tested to see their effect on the activity of some important parameters of Gigantocotyle explanatum worms, including Gamma-glutamyl Transpeptidase (GGT), glutathione (GSH), Glutathione-S-Transferase (GST), Superoxide dismutase (NO). Additionally, various other survival indicators are also used, such as assays for motility, tegument damage, and DNA fragmentation. G. explanatum adult flukes were in vitro treated to thymoquinone at various concentrations for 3 h at 37 °C. Even though all of the worms were still alive after 3 h of exposure, there was a substantial (p < 0.05) reduction in worm motility at a concentration of 90 M. There were pronounced tegumental disturbances, a loss of surface annulations, and erosion in the papillae posterior region and around the acetabulum. A significant (p < 0.05) decrease in glutathione-S-transferase and superoxide dismutase activity and reduced glutathione (GSH) level was observed. A significant inhibition of Gamma-glutamyl Transpeptidase (GGT) in thymoquinone treated worms was also evident. Thymoquinone and GGT also displayed a high interaction during in silico molecular docking, suggesting that this combination may be more effective at inhibiting the antioxidant enzymes of G. explanatum. The present findings suggest that thymoquinone would reduce the worm capacity for detoxification, while GGT inhibition would have a major impact on their ability to transport amino acids across the tegument. Thymoquinone thus seemed to be a promising anthelmintic compound for future investigations.