A recent study has reportedly identified an alternative hormonal receptor that mediates bisphenol A (BPA), raising questions about the purported link between BPA exposure, diabetes and obesity. Marie Tohmé, et al., “Estrogen-related receptor γ is an in vivo receptor of bisphenol A,” The Journal of the Federation of American Societies for Experimental Biology, April 2014. Researchers with the Institute of Functional Genomics of Lyon (ENS de Lyon) and Deakin University apparently used a zebrafish model to demonstrate that “the in vivo action of [BPA] was mediated by the orphan nuclear receptor, ERRy (estrogen-related receptor),” which previous studies have implicated in metabolism regulation, insulin secretion, newborn obesity, and inner ear development.
“We found that the way the BPA binds to and activates ERRy is 1000 times better than with the estrogen receptor. This means that ERRy is 1000 times more potent; a tiny amount of BPA will result in a huge activation of ERRy but only a mild activation of estrogen receptors,” explained one study author in an April 29, 2014, Deakin University Press release. “As the current guidelines are based on the activation of estrogen receptors, we need to rethink the tolerable daily intake as BPA will induce effects at a lower dose than currently acknowledged. In Europe this is already happening with the intake soon to be dropped to 5 micrograms per kilo per day.” See ENS de Lyon Press Release, April 22, 2014.