Infusion of high concentration of lactate in perfused liver, simulating in vivo hyperlactatemia, prevents the reduction of gluconeogenesis in Walker-256 tumor-bearing rats

Gluconeogenesis is reduced from alanine, lactate and pyruvate, but maintained from glycerol, in liver perfusion of rats with early and late sepsis

Sepsis induces several metabolic abnormalities, including hypoglycaemia in the most advanced stage of the disease, a risk factor for complications and death. Although hypoglycaemia can be caused by inhibition of hepatic gluconeogenesis, decreased and increased gluconeogenesis were reported in sepsis. Furthermore, gluconeogenesis from glycerol was not yet evaluated in this disease. The main purpose of this study was to investigate the gluconeogenesis from alanine, lactate, pyruvate and glycerol in rats with early (8 hours) and late (18 hours) sepsis. Parameters related to the characterization of sepsis were also evaluated. Sepsis was induced by cecal ligation and puncture and gluconeogenesis was assessed in liver perfusion. Rats with early and late sepsis showed increased lactataemia, depletion of liver glycogen and peripheral insulin resistance, characterizing the establishment of sepsis. Rats with early and late sepsis showed decreased gluconeogenesis from alanine, lactate and pyruvate. Interestingly, gluconeogenesis from glycerol, a precursor that enters in the pathway at a later step, subsequent to the entry of alanine, lactate and pyruvate, was maintained in rats with early and late sepsis. In conclusion, gluconeogenesis is decreased from alanine, lactate and pyruvate, but maintained from glycerol, in liver perfusion of rats with early and late sepsis. SIGNIFICANCE OF THE STUDY: The maintenance of gluconeogenesis from glycerol, but not from alanine, lactate and pyruvate, together with the liver glycogen depletion, points the glycerol as an important precursor for the maintenance of glycaemic homeostasis in sepsis. The findings open the possibility of further investigation on the administration of glycerol in the treatment of hypoglycaemia associated with more advanced sepsis.