Interestingly, in cultured glutamatergic cerebellar neurons, it has been shown that the endogenous neurotransmitter glutamate generated from glutamine via PAG can enter the TCA cycle via AAT [55].Our data show an increased production of endogenous [U-13C] glutamate synthesised from [U-13C] glutamine consistent with an increased PAG expression in the FTD neurons. The gene discussed is SERPINA1; the disease is frontotemporal dementia.