The glutathione cycle shapes synaptic glutamate activity bioRxiv Disrupting Mitochondrial Pyruvate Uptake Directs Glutamine into the TCA Cycle away from Glutathione Synthesis and Impairs Hepatocellular Tumorigenesis: Cell Reports Role of glutamine, as free or dipeptide form, on muscle recovery from resistance training: a review study Nutrire Springer Nature Link It turns out that T cells utilize quite a bit of glutamine to a) replenish TCA cycle intermediates ('anaplerosis') as well as to b) exchange for other amino acids.