Increased concentration of fructose 2,6‐bisphosphate in livers of genetically obese mice

Regulatory Role of Fructose-2,6-Bisphosphate in Pancreatic Islet Glucose Metabolism Remains Unsettled

“…The fructose-2,6-P 2 content of islet tissue sampled during the second phase of glucose-stimulated insulin secretion is very low, about 10% of that reported in liver tissue from fed rats (compare Table 1 with refs. [27][28][29]. In fact, fructose-2,6-P 2 levels in freshly isolated islet tissue from fed rats were comparable to levels reported in livers from fasted rats (<1 |xM) and observed herein in studies of liver tissue.…”

Gluconeogenesis and Related Aspects of Glycolysis

“…Its concentration in the liver of a well-fed rat is in the range of 10-20 ftM, and reaches very low values during prolonged fa sting and diabetes (172, 230--232), but remains elevated in the liver of fasted genetically obese mice (233). In hepatocytes fr om fed rats incubated in the presence of 20-mM glyceraldehyde, fr uctose, lactate, glycerol, pyruvate, or alanine, the concentration of fructose 2,6-bisphosphate was only 10%-50% that in the control (231).…”

Role of fructose 2,6-bisphosphate in the control of glycolysis in mammalian tissues

“…An increase in liver Fru-2,6-P2 is not only obtained after a glucose load in normal animals. It is also observed even during fasting in livers of genetically obese mice and rats [110][111][112]. This high glycolysis may contribute to obesity by keeping lipogenesis active even in the fasted state.…”