title: Phenylalanine ammonia-lyase immobilized in microcapsules for the depletion of phenylalanine in plasma in phenylketonuric rat model.
abstract: Microencapsulation of the enzyme phenylalanine ammonia-lyase was developed for in vivo depletion of systemic phenylalanine in phenylketonuric rats. Compared to normal rats, systemic phenylalanine blood levels in phenylketonuric rats was increased by 15-20-fold. Daily oral administration of 1 unit of phenylalanine ammonia-lyase-loaded artificial cells to phenylketonuric rats lowered the systemic phenylalanine level to 58% +/- 18% (mean + S.D.) in 7 days (P less than 0.010), while 5 units lowered the systemic phenylalanine level to 25% +/- 8%. 5 units of the immobilized enzyme lowered the systemic phenylalanine level to normal levels within 6 days. Phenylketonuric treated rats showed no signs of abnormal behavior and weight loss compared to phenylketonuric non-treated rats. The immobilized enzyme within artificial cells is therefore protected against low gastrointestinal pH and proteolytic enzymes.
mesh_terms: D000642:Ammonia-Lyases / Q000627:therapeutic use*; D000818:Animals; D002214:Capsules; D004800:Enzymes, Immobilized / Q000627:therapeutic use*; D008297:Male; D010649:Phenylalanine / Q000097:blood*; D010650:Phenylalanine Ammonia-Lyase / Q000097:blood / Q000627:therapeutic use*; D010661:Phenylketonurias / Q000097:blood / Q000188:drug therapy*; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D002214:Capsules; D004800:Enzymes, Immobilized; D010649:Phenylalanine; D000642:Ammonia-Lyases; D010650:Phenylalanine Ammonia-Lyase