Efficacy of Thunbergia laurifolia crude extracts against carcinogenic liver fluke, Opisthorchis viverrini

The human liver fluke, Opisthorchis viverrini, is a significant risk factor for cholangiocarcinoma (CCA) in Thailand. Praziquantel (PZQ) is the primary treatment for opisthorchiasis but is associated with adverse effects and the potential development of CCA amid chronic infection and reinfection, prompting the search for alternative treatments. Thunbergia laurifolia is widely used for detoxification from lead poisoning and other toxins. The bioactive compounds of T. laurifolia are categorized into sterols, phenolics, carotenoids, glycosides, and unclassified steroids. It is considered an herb that contains a variety of active compounds, which may demonstrate effectiveness in eliminating parasites. This study evaluated the anthelmintic efficacy of crude extracts of Thunbergia laurifolia on newly excysted juveniles (NEJs) and adult stages of O. viverrini.The experiments were involved treating O. viverrini NEJs and adult worms with various concentrations of the crude extracts (NEJs: 5, 10, 20, 40 mg/ml; adult worms: 20, 30, 40 mg/ml), with PZQ and RPMI-1640 medium serving as positive and negative controls, respectively. An assessment of relative motility (RM) and survival index (SI) was conducted, along with a morphological evaluation using scanning electron microscopy (SEM) and biochemical tests to evaluate the generation of reactive oxygen species (ROS) as a response to stress. Results showed that T. laurifolia crude extract reduced RM and SI of the O. viverrini NEJs and adult worms. SEM revealed minimal tegumental damage when compared to the positive control group. Elevated ROS levels were significantly higher, suggesting oxidative stress as a potential mechanism of action. These findings suggest that T. laurifolia possess promising anthelmintic properties against O. viverrini, meriting further research to isolate active compounds and elucidate their mechanisms. Such studies could lead to the development of novel herbal treatments for opisthorchiasis.