Regulation of BCRP expression and sulfasalazine pharmacokinetics by the nuclear receptor REV-ERBα

BCRP (breast cancer resistance protein) is a crucial efflux transporter involved in the regulation of the pharmacokinetics and pharmacodynamics of a wide range of drugs. Herein, we aimed to investigate a potential role for the nuclear receptor REV-ERBα in the regulation of BCRP expression and sulfasalazine (a BCRP probe substrate) pharmacokinetics.Regulation of BCRP expression by REV-ERBα was assessed using Rev-erbα^-/- mice and AML12 and CT26 cells. Pharmacokinetic analysis was performed with Rev-erbα^-/- and wild-type mice after sulfasalazine administration.We found that the expression levels of BCRP mRNA and protein were downregulated in the liver and small intestine of Rev-erbα-dificient mice. In line with this, Rev-erbα ablation increased the systemic exposures of oral sulfasalazine.Positive regulation of BCRP expression and function by REV-ERBα was furtherly confirmed in AML12 and CT26 cells. Moreover, indirect regulation of Bcrp expression by REV-ERBα was potentially mediated by a negative transcription factor DEC2, which is a downstream target of REV-ERBα.In conclusion, REV-ERBα positively regulates BCRP expression in mice, thereby affecting sulfasalazine pharmacokinetics.