PFKP and depressive disorder: Comparing the glycolytic expression profiles between severe mental illnesses and ketogenic datasets revealed a discordant expression pattern in the schizophrenia–ketosis (Table 2) and major depressive disorder–ketosis comparisons (Table 4), where ENO1 was upregulated in schizophrenia, the rate-limiting enzyme PFKP was upregulated in depression, and both were downregulated in ketosis.