Lipid Accumulation in Blastocystis Increases Cell Damage in Co-Cultured Cells

is an intestinal protozoan that is often neglected, despite causing abdominal pain and diarrhea. Previous research has demonstrated that lipids can be synthesized by or can accumulate in growth medium, but their function and mechanisms in the pathogenesis of remain unclear. Our study found that lipid-rich ST7-B can increase inflammation and disrupt Caco-2 cells more than the same parasite without the lipovenoes supplement. Additionally, the cysteine protease of , a virulence factor, is upregulated and has higher activity in lipid-rich . In order to better understand the effects of lipids on pathogenesis, we treated lipid-lowering pravastatin during ST7-B culturing with a lipovenoes supplement, which decreased the lipid levels of the and reduced the -induced inflammation and cell disruption of Caco-2 cells. We also analyzed the fatty acid composition and possible synthesis pathway in ST7-B, finding significantly higher ratios of arachidonic acid, oleic acid, and palmitic acid than in the other lipid components in lipid-rich ST7-B. These results suggest that lipids play a significant role in the pathogenesis of and provide important information on the molecular mechanisms of and potential treatments for infection.