ATF3 mediates inhibitory effects of ethanol on hepatic gluconeogenesis

作者:Tsai Wen Wei; Matsumura Shigenobu; Liu Weiyi; Phillips Naomi G; Sonntag Tim; Hao Ergeng; Lee Soon; Hai Tsonwin; Montminy Marc*
来源:Proceedings of the National Academy of Sciences, 2015, 112(9): 2699-2704.
DOI:10.1073/pnas.1424641112

摘要

Increases in circulating glucagon during fasting maintain glucose balance by stimulating hepatic gluconeogenesis. Acute ethanol intoxication promotes fasting hypoglycemia through an increase in hepatic NADH, which inhibits hepatic gluconeogenesis by reducing the conversion of lactate to pyruvate. Here we show that acute ethanol exposure also lowers fasting blood glucose concentrations by inhibiting the CREB-mediated activation of the gluconeogenic program in response to glucagon. Ethanol exposure blocked the recruitment of CREB and its coactivator CRTC2 to gluconeogenic promoters by up-regulating ATF3, a transcriptional repressor that also binds to cAMP-responsive elements and thereby down-regulates gluconeogenic genes. Targeted disruption of ATF3 decreased the effects of ethanol in fasted mice and in cultured hepatocytes. These results illustrate how the induction of transcription factors with overlapping specificity can lead to cross-coupling between stress and hormone-sensitive pathways.

  • 出版日期2015-3-3