Identification of LPS-inducible genes down-regulated by ubiquinone in human THP-1 cells

Coenzyme Q10 (CoQ10) is an obligatory element in the respiratory chain and functions as a potent antioxidant of lipid membranes. More recently, anti-inflammatory effects as well as an impact of CoQ10 on gene expression have been observed. To reveal putative effects of Q10 on LPS-induced gene expression, whole genome expression analysis was performed in the monocytic cell line THP-1. 1129 probe sets have been identified to be significantly up-regulated (p < 0.05) in LPS-treated cells when compared to controls. Text mining analysis of the top 50 LPS up-regulated genes revealed a functional connection in the NFB pathway and confirmed our applied in vitro stimulation model. Moreover, 33 LPS-sensitive genes have been identified to be significantly down-regulated by Q10-treatment between a factor of 1.32 and 1.85. GeneOntology (GO) analysis revealed for the Q10-sensitve genes a primary involvement in protein metabolism, cell proliferation and transcriptional processes. Three genes were either related to NFB transcription factor activity, cytokinesis or modulation of oxidative stress. In conclusion, our data provide evidence that Q10 down-regulates LPS-inducible genes in the monocytic cell line THP-1. Thus, the previously described effects of Q10 on the reduction of pro-inflammatory mediators might be due to its impact on gene expression.

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Schmelzer C, Döring F