Simvastatin exerts antifibrotic effect and potentiates the antischistosomal effects of praziquantel in a murine model: Role of IL10

Tetrylpyamethrazine alleviates hepatic fibrosis induced by experimental mansonic schistosomiasis

Hepatic fibrosis resulting from human mansonic schistosomiasis significantly impairs liver function and contributes substantially to morbidity associated with helminth infections. This pathological state develops following the deposition of helminth eggs within hepatic tissues, triggering a granulomatous inflammatory reaction. Schistosomiasis, a neglected tropical disease affecting approximately 240 million individuals globally, represents a major public health challenge. Although praziquantel (PZQ) is recommended by the World Health Organization (WHO) as the primary treatment for helminth infections, additional therapies are required to address the associated liver fibrosis. This study investigated the efficacy of tetramethylpyrazine (TMP), a natural compound known for its anti-inflammatory, antifibrotic, and hepatoprotective properties in various experimental models, in mitigating hepatic fibrosis induced by mansonic schistosomiasis. Our in vivo experiments demonstrated that TMP treatment significantly reduced hepatic granuloma size, as evidenced by histological analysis. Furthermore, our in vitro studies showed that TMP increased levels of the anti-inflammatory cytokine IL-10 while decreasing levels of the profibrotic cytokine IL-13 in a concentration-dependent manner. Immunofluorescence analysis also revealed that TMP effectively inhibited collagen deposition. Collectively, these findings suggest that TMP exhibits potential as an anti-inflammatory and antifibrotic agent for hepatic fibrosis resulting from Schistosoma mansoni infection.

The Activity of Plant Crude Extracts against Schistosoma mansoni

Background

Schistosoma mansoni remains a significant health problem in low-income countries. Praziquantel (PZQ) is the only drug available to treat schistosomiasis, and PZQ resistance is a potential threat towards control of the disease although PZQ is currently effective against all species of schistosomes. Moreover, PZQ is less efficacious against larval stages. In response to these challenges, multiple in vivo/in vitro studies evaluated the anti-S. mansoni activity of crude plant extracts in a bid for novel drug(s). However, these studies appear fragmented and patchy. This systematic review explored the extent of such studies in the past 11 years (2010-2020).

Methods

A systematic web search analysis and review of the literature on crude plant extracts tested against S. mansoni was done. Data from 17 articles meeting eligibility criteria were extracted and analyzed. Forty-three plant species have been tested by the 17 studies. The leaves, barks, stems, flowers, rhizomes, and roots of the plants as well as the whole plant part were used for the experiments.

Conclusion

Nearly all of the plants significantly reduced schistosome egg output, killed adult worms, and improved liver histology and function. Further studies are required to assess the therapeutic potential of more promising plant species.

Investigating the antifibrotic effect of the antiparasitic drug Praziquantel in in vitro and in vivo preclinical models

Tissue fibrosis underlies the majority of human mortality to date with close to half of all reported deaths having a fibrotic etiology. The progression of fibrosis is very complex and reputed irreversible once established. Although some preventive options are being reported, therapeutic options are still scarce and in very high demand, given the rise of diseases linked to fibroproliferative disorders. Our work explored four platforms, complementarily, in order to screen preventive and therapeutic potentials of the antiparasitic drug Praziquantel as a possible antifibrotic. We applied the mouse CCl₄-driven liver fibrosis model, the mouse chronic schistosomiasis liver fibrosis model, as well as novel 2D and 3D human cell-based co-culture of human hepatocytes, KCs (Kupffer cells), LECs (Liver Endothelial Cells), HSCs (Hepatic Stellate Cells) and/or myofibroblasts to mimic in vivo fibrotic responses and dynamics. Praziquantel showed some effect on fibrosis marker when preventively administered before severe establishment of fibrosis. However, it failed to potently reverse already established fibrosis. Together, we provided a novel sophisticated multi-assay screening platform to test preventive and therapeutic antifibrotic candidates. We further demonstrated a direct preventive potential of Praziquantel against the onset of fibrosis and the confirmation of its lack of therapeutic potential in reversing already established fibrosis.

Effects of supramolecular complexation of praziquantel with disodium glycyrrhizinate on the liver fluke Opisthorchis felineus: An in vitro and in vivo study

Millions of people worldwide have a chronic infection with the liver fluke Opisthorchis felineus, which causes opisthorchiasis in humans and animals. The only known effective drug for this disease is praziquantel (PrzQ); however, its efficacy is below 100%, and it has some adverse effects. In this study, a water-soluble complex of PrzQ with a disodium salt of glycyrrhizic acid (disodium glycyrrhizinate; Na₂GA) in a 1:10 ratio (PrzQ:GA) allowed the PrzQ dose to be decreased 11-fold for effective killing of O. felineus. An in vitro experiment showed a sufficient anthelmintic efficiency of PrzQ:GA against both adult and juvenile O. felineus individuals. A Syrian golden hamster model of opisthorchiasis revealed a considerable anthelmintic effect at all tested PrzQ:GA doses (50, 100, 200, 400, and 1100 mg/kg) with the best performance at 400 and 1100 mg/kg. Further comparison of the effects of PrzQ (400 mg/kg) and PrzQ:GA (400 mg/kg) regarding the state of the host indicated significant advantages of the latter. Histological examination showed that PrzQ:GA was better at decreasing the O. felineus-induced inflammatory infiltration (as compared with PrzQ alone) as well as interfered with the development of epithelial dysplasia and metaplasia in large bile ducts and cholangiofibrosis. Both PrzQ and PrzQ:GA decreased the number of myeloid (CFU-GM) and erythroid (BFU-E + CFU-E) colonies induced by O. felineus infection. The drugs had no negative effect on the animal behavior in an open field test 2-4 h after administration. Thus, PrzQ:GA proved to be a good anthelmintic agent having no evident adverse effects on the host, thereby suggesting that further preclinical and clinical trials would be warranted.