Effect of branched-chain amino acids on glutamate metabolism in amyotrophic lateral sclerosis.

Data from the literature about glutamate metabolism remain controversial. To refine such analysis we have studied plasma glutamate and aspartate levels after glutamate loading (60 mg/kg) in 6 fasting controls and ALS patients, before and after at least 2 weeks treatment with branched-chain amino acids. ALS patients showed no difference from age-matched controls in basal plasma glutamate or aspartate levels, but significantly elevated levels of glutamate and aspartate at 30 and 45 min after loading, and an increased area under the curve in plasma for glutamate following oral glutamate loading. Two weeks BCAAs treatment did not affect plasma glutamate metabolism in ALS patients.