Figure 3.
Guanides/biguanides non-competitively inhibit rat and human mGPD activity. (a) Guanides/biguanides inhibit rat mGPD activity by 30–50% in rat mitochondrial lysate. Data shown is the average of 3 experiments. (b) Metformin (50 μM) inhibited mitochondrial respiration from glycerol-3-phosphate. (c) Metformin inhibited recombinant human mGPD non-competitively as determined by Michaelis-Menten and Eadie-Hofstee plots of the kinetic data. Data shown is representative of 2 experiments. Data are mean ± SEM, (n=5 technical replicates for mGPD activity in lysate; nontreat n=12, metformin n=12 technical replicates for oxygen consumption). * P<0.05, **P<0.01, ***P<0.001 by unpaired t-test.