Lipid and Cholesterol Homeostasis after Arsenic Exposure and Antibiotic Treatment in Mice: Potential Role of the Microbiota

BACKGROUND: Arsenic-induced liver X receptor/retinoid X receptor (LXR/RXR) signaling inhibition is a potential mechanism underlying the cardiovascular effects caused by arsenic. The gut microbiota can influence arsenic toxic effects. OBJECTIVE: We aimed to explore whether gut microbiota play a role in arsenic-induced LXR/RXR signaling inhibition and the subsequent lipid and cholesterol dysbiosis. METHODS: arsenic for 2 wk. Hepatic mRNAs were extracted and sequenced. The expression levels of genes associated with LXR/RXR signaling were quantified by quantitative real-time polymerase chain reaction (qPCR), and serum and hepatic cholesterol levels were measured. Liquid chromatography-mass spectrometry (LC-MS)-based lipidomics were used to examine serum and hepatic lipids. RESULTS: arsenic, while arsenic exposure did not significantly affect the serum lipids in AB-treated mice. Liver lipid patterns were also differentially perturbed in a microbiota-dependent manner. CONCLUSIONS: Our results suggest that in mice, the gut microbiota may be a critical factor regulating arsenic-induced LXR/RXR signaling perturbation, suggesting that modulation of the gut microbiota might be an intervention strategy to reduce the toxic effects of arsenic on lipid and cholesterol homeostasis. https://doi.org/10.1289/EHP4415.