Spatial hepatocyte plasticity of gluconeogenic gene expression and gluconeogenic activity during the metabolic transitions between fed, fasted and starvation states [targeted scRNA-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. Mice were trained for 3 days by removing food at 5PM and feeding at 9:00 the next day (16h fasting overnight and 8h feeding daytime). On the day of experiment, mice were provided food with drinking water that contained 20% of sucrose. The fed (0h) mice were sacrificed at 13:00 equal to 4h of feeding (0h). For fasted mice, the food and sucrose water were taken out at 13:00, then sacrificed at 21:00 for fast 8h (8h), 5:00 the next day for fast16h (16h), 13:00 the next day for fast 24h (24h), and 19:00 the next day for fast 30h (30h).