Glucose feeds the TCA cycle via circulating lactate.

ABSTRACT: Mammalian tissues are fuelled by circulating nutrients, including glucose, amino acids, and various intermediary metabolites. Under aerobic conditions, glucose is generally assumed to be burned fully by tissues via the tricarboxylic acid cycle (TCA cycle) to carbon dioxide. Alternatively, glucose can be catabolized anaerobically via glycolysis to lactate, which is itself also a potential nutrient for tissues and tumours. The quantitative relevance of circulating lactate or other metabolic intermediates as fuels remains unclear. Here we systematically examine the fluxes of circulating metabolites in mice, and find that lactate can be a primary source of carbon for the TCA cycle and thus of energy. Intravenous infusions of ¹³C-labelled nutrients reveal that, on a molar basis, the

SUBMITTER: Hui S 

PROVIDER: S-EPMC5898814 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature