title: Oral administration of alpha-ketoisovaleric acid or valine in humans: blood kinetics and biochemical effects.
abstract: alpha-Ketoisovaleric acid levels increase from 10.6 +/- 0.8 to 121 +/- 20 mumol/L, and valine levels increase from 175 +/- 14 to 940 +/- 50 mumol/L after oral administration of an isomolar (62.5 mg/kg) bolus of alpha-ketoisovaleric acid or valine to healthy human subjects. alpha-Ketoisovaleric acid levels have a different time course relative to valine. alpha-Ketoisovaleric acid and valine affect various other amino and keto acids, and some of these effects are qualitatively different. alpha-Ketoisovaleric acid enhances alpha-ketoisocaproic acid and alpha-keto-beta-methyl-n-valeric acid, but diminishes the corresponding amino acids, and causes an early decline of ornithine along with a late augmentation of plasma arginine. Valine does the opposite. The data suggest that in humans, overall capacity for alpha-ketoisovaleric acid decarboxylation appears greater than the capacity for valine transamination, and that all branched-chain amino acids and branched-chain keto acids seem to be interconvertible by reversible transaminations.
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000596:Amino Acids / Q000097:blood; D000597:Amino Acids, Branched-Chain / Q000097:blood; D001774:Blood Chemical Analysis; D001786:Blood Glucose / Q000378:metabolism; D001806:Blood Urea Nitrogen; D005260:Female; D005934:Glucagon / Q000097:blood; D045782:Hemiterpenes; D006801:Humans; D007328:Insulin / Q000097:blood; D007651:Keto Acids / Q000097:blood / Q000494:pharmacology*; D007700:Kinetics; D008297:Male; D014508:Urea / Q000097:blood; D014633:Valine / Q000097:blood / Q000494:pharmacology*
chemical_list: D000596:Amino Acids; D000597:Amino Acids, Branched-Chain; D001786:Blood Glucose; D045782:Hemiterpenes; D007328:Insulin; D007651:Keto Acids; C001505:alpha-ketoisovalerate; D014508:Urea; D005934:Glucagon; D014633:Valine