SR-9011

SR-9011 is a synthetic small molecule that acts as a potent agonist of REV-ERB nuclear receptors, specifically REV-ERBa and REV-ERBb. These receptors function as transcriptional repressors that sit at the intersection of circadian rhythm regulation and metabolic homeostasis. By pharmacologically activating REV-ERB, SR-9011 directly modulates the molecular clock machinery and simultaneously engages metabolic pathways governing energy expenditure, lipid oxidation, gluconeogenesis, adipogenesis, and inflammatory responses. It is classified as a research compound and has no approved clinical use.

The biological role of REV-ERBa is to act as a heme-sensing transcriptional repressor, binding to response elements in the promoters of core circadian clock genes (including Bmal1 and Clock) and metabolic target genes. When SR-9011 activates REV-ERBa, it reinforces the repressor function of these receptors, shifting circadian gene expression in ways that alter the timing and magnitude of metabolic activity. Published preclinical research in the journal Nature (2012) showed that pharmacological REV-ERB activation with SR-9011 increased metabolic rate, reduced fat mass, decreased plasma triglycerides and cholesterol, and improved glucose tolerance in diet-induced obese mice.

The endurance and exercise-related interest in SR-9011 stems from its effects on skeletal muscle energy metabolism. Animal studies have shown that REV-ERB activation increases oxidative capacity in muscle cells, promoting mitochondrial biogenesis and fatty acid oxidation pathways that parallel those engaged during aerobic exercise. Administration of SR-9011 in preclinical models produced measurable improvements in running endurance, consistent with enhanced mitochondrial function and substrate utilization. However, all human pharmacokinetic and efficacy data are absent, as no human clinical trials have been conducted.

SR-9011 also exhibits anti-inflammatory properties mediated through REV-ERBa's role in macrophage function. Research published in 2020 demonstrated that SR-9011 suppressed pro-inflammatory cytokine production in microglia, the resident immune cells of the central nervous system. This neuroinflammatory modulation adds another dimension to the compound's research interest, particularly in the context of neurodegenerative disease models. SR-9011 has a short estimated half-life of approximately 4 hours in preclinical models, which has significant implications for dosing strategy in any future human application.