The regulation of Niemann-Pick C1-Like 1 (NPC1L1) gene expression in opposite direction by and related outer membrane vesicles in Caco-2 cell line.

PURPOSE

The intestine has substantial role in cholesterol homeostasis due to the presence of various cholesterol transporters and gut microbiota. spp. are important members of gut microbiota that employ outer membrane vesicles (OMVs) to interact with host. In this regard, we evaluated the effect of and related OMVs on the gene expression of important cholesterol transporters, Niemann-Pick C1-Like 1 (), ATP-binding cassette (), and liver X receptors (s) in Caco-2 cells.

METHODS

OMVs were isolated from overnight brain heart infusion (BHI) broth of bacterial standard strains using deoxycholate and assessed by Scanning electron microscopy (SEM). The relative change in genes expression was assessed by Quantitative reverse transcription PCR (RT-qPCR) based on SYBR Green and 2 method in Caco-2 cells that were treated with bacteria and OMVs. Data were statistically analyzed with GraphPad Prism software. Finally, pathway enrichment based on the studied genes was performed using Cytoscape plugin ClueGO.

RESULTS

( = 0.002) and ( = 0.001) significantly reduced gene expression in Caco-2 cells. Interestingly, transcripts were significantly increased by both OMVs( = 0.04) ( = 0.01). Also, was significantly down regulated by ( = 0.02) ClueGO analysis on the studied genes demonstrated several functional groups which involve in lipid and cholesterol metabolism.

CONCLUSION

The opposite effect of , and related OMVs on the gene expression was observed in Caco-2 cells. Interestingly, these effects partially were in line with the alternation of s expression. However, based on pathway enrichment analysis, further molecular investigations are required to elaborate in details the specific association between spp. and OMVs with regulation of cholesterol signaling pathways including cholesterol transport, lipid storage, lipid homeostasis and cholesterol homeostasis.