Spatial hepatocyte plasticity of gluconeogenic gene expression and gluconeogenic activity during the metabolic transitions between fed, fasted and starvation states [RNA-Seq]

Single cell analyses of hepatocytes across the liver lobule demonstrated that gluconeogenic gene expression (Pck1 and G6pc) is relatively low in the fed state and gradually increase first in the periportal hepatocytes during the initial fasting period. As the time of fasting progresses, pericentral hepatocyte gluconeogenic gene expression increases and following entry into the starvation state the pericentral hepatocytes are not significantly different than the periportal hepatocytes. Similarly, pyruvate-dependent gluconeogenic activity is approximately 10-fold higher in the periportal hepatocytes during the initial fasting states but with only 1.5-fold different between the pericentral and periportal hepatocytes in the starvation state. In parallel, starvation induced a reduction of canonical beta-catenin signaling and redistribution of pericentral and periportal glutamine synthetase and glutaminase resulting in an enhanced pericentral glutamine-dependent gluconeogenesis. These data demonstrate that hepatocyte gluconeogenic gene expression and gluconeogenic activity are highly spatially and temporally plastic across the liver lobule and underscore the critical importance of using well-defined feeding and fasting times to define the basis of hepatic insulin resistance and glucose production.