Developmental Exposure to 2,2’,4, 4’ –Tetrabromodiphenyl Ether Induces Long-Lasting Changes in Liver Metabolism in Male Mice. Mus musculus

Polybrominated diphenyl ethers (PBDEs) were used as flame-retardant additives in a wide range of polymers starting in 1965 and were recently withdrawn from commerce in North America and Europe. Generations that were exposed perinatally to the highest environmental doses of PBDE have now reached 5-20 years of age and in the U.S. account for 1/5 of the total population. Emerging data indicates long-term impairment of metabolic health by PBDE exposure in humans and laboratory animals. We hypothesize that exposure to PBDE during sensitive developmental windows may result in long-lasting changes in liver metabolism. In this study pregnant CD-1 mice were exposed to 0.2 mg/kg 2,2’,4,4’-tetrabromodiphenyl ether (BDE-47) from gestation day 8 till postnatal day 21 and liver RNA-seq was performed on the last day of dam exposure and on postnatal week 20 in male offspring. Several groups of metabolic genes, including ribosomal and mitochondrial genes were significantly upregulated at both time-points. Genes regulated via mechanistic target of rapamycin (mTOR pathway), the gatekeeper of metabolic homeostasis, were whether up- or down- regulated at both time-points. Thus, perinatal exposure to environmentally relevant doses of BDE-47 in laboratory mice results in long-lasting changes in liver metabolism. Our evidence suggests involvement of the mTOR pathway in the observed metabolic programming of liver. Overall design: RNA-seq analysis of liver genes in control and exposed male mice (n = 4-5/exposure) on postanatal day 21 and postnatal week 20 following perinatal exposure to BDE-47