PHGDH and amyotrophic lateral sclerosis: The activity of total malate dehydrogenase (MDH) increased in the ALS I and ALS I SWIM groups (7.018 ± 0.21 and 5.982 ± 0.19 μmol/min/mg of protein, respectively) vs. the ALS 0 group (4.300 ± 0.09 μmol/min/mg of protein) (p = 0.0001) and corresponding WT group of mice (p = 0.0001).