title: Erythrocyte L-aspartyl-L-phenylalanine hydrolase activity and plasma phenylalanine and aspartate concentrations in children consuming diets high in aspartame.
abstract: A deficit of alpha-aspartyl-phenylalanine (alpha-Asp-Phe) hydrolase activity has been suggested as a cause of possible adverse effects of aspartame ingestion. Twenty-five normal preschool children and 23 school-age children described by their parents as sensitive to sugar were fed diets high in sucrose, aspartame, or saccharin for three successive 3-wk periods. Blood samples were obtained at baseline (fasting) and within the last 3 d of each dietary period (postprandial). alpha-Asp-Phe concentrations were below detection limits (0.5 mumol/L) in all plasma samples and Phe and Asp concentrations remained within normal limits, alpha-Asp-Phe hydrolase activities in baseline hemolysate samples did not differ between groups. One subject had a plasma alpha-Asp-Phe hydrolase activity > 2 SD below the mean. Despite this low activity, this subject did not show consistent cognitive or behavioral anomalies that could be linked to low hydrolase activity.
mesh_terms: D000375:Aging / Q000097:blood; D000704:Analysis of Variance; D001218:Aspartame / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D001224:Aspartic Acid / Q000097:blood*; D002648:Child; D002652:Child Behavior / Q000187:drug effects; D002675:Child, Preschool; D003071:Cognition / Q000187:drug effects; D004032:Diet; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004912:Erythrocytes / Q000201:enzymology*; D006801:Humans; D006867:Hydrolases / Q000097:blood*; D010649:Phenylalanine / Q000097:blood*; D013549:Sweetening Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*
chemical_list: D013549:Sweetening Agents; D001224:Aspartic Acid; D010649:Phenylalanine; D006867:Hydrolases; D001218:Aspartame