Targeting REV-ERBα for therapeutic purposes: promises and challenges

REV-ERB (NR1D1) is a circadian clock component that functions as a transcriptional repressor. Due to its role in direct modulation of metabolic genes, REV-ERB is regarded as an integrator of cell metabolism with circadian clock. Accordingly, REV-ERB is first proposed as a drug target for treating sleep disorders and metabolic syndromes (e.g., dyslipidaemia, hyperglycaemia and obesity). Recent years of studies uncover a rather broad role of REV-ERB in pathological conditions including local inflammatory diseases, heart failure and cancers. Moreover, REV-ERB is involved in regulation of circadian drug metabolism that has implications in chronopharmacology. In the meantime, recent years have witnessed discovery of an array of new REV-ERB ligands most of which have pharmacological activities in vivo. In this article, we review the regulatory role of REV-ERB in various types of diseases and discuss the underlying mechanisms. We also describe the newly discovered ligands and the old ones together with their targeting potential. Despite well-established pharmacological effects of REV-ERB ligands in animals (preclinical studies), no progress has been made regarding their translation to clinical trials. This implies certain challenges associated with drug development of REV-ERB ligands. In particular, we discuss the potential challenges related to drug safety (or adverse effects) and bioavailability. For new drug development, it is advocated that REV-ERB should be targeted to treat local diseases and a targeting drug should be locally distributed, avoiding the adverse effects on other tissues.