Glutamine: an anaplerotic precursor

A Metabolomics-driven Elucidation of the Anti-obesity Mechanisms of Xanthohumol

“…In XN-treated myocytes, metabolomics revealed a transient increase in several uncharacterized di-and tripeptides as well as the majority of amino acids, indicative of protein degradation and amino acid mobilization for entry into the TCA cycle. Free glutamine is present in muscle at high concentrations and is a major amino acid feeding the TCA cycle (55,56). Glutamine is first converted to glutamate, which can then produce the TCA cycle intermediate oxoglutarate.…”

Glutamine and glutamate as vital metabolites

“…The rate of TCA cycle flux and so oxidative metabolism is limited by the concentration of the TCA cycle intermediates. The dramatic decline in intramuscular glutamate at the start of exercise with the concomitant increase in intramuscular alanine suggests that glutamate is an important anaplerotic precursor (73,74).…”

Candidate mechanisms accounting for effects of physical activity on breast carcinogenesis

“…In contracting skeletal muscle, aerobic metabolism involves glycolytic conversion of glucose via pyruvate into acetyl-CoA and its complete oxidation through the mitochondrion-localized tricarboxylic acid (TCA) cycle and oxidative phosphorylation to CO 2 and H 2 O which generates 38 ATP molecules per molecule of glucose. Duration exercise, TCA cycle flux increases to meet requirements for ATP and can entail a 60 to 100 fold increase in the concentration of TCA cycle intermediates in part through anapleurotic mechanisms involving various glycolytic products and amino acids, prominent among which are pyruvate, glutamine, and alanine (50;51). Catapleurosis also occurs during exercise affecting circulating levels of pyruvate, alanine, as well as glucose and glutamine (52).…”