Inhibitory effect of thiols on the degradation of albumin by human spleen cathepsin D.
The degradation of native albumin by human spleen cathepsin D was inhibited by GSH, cysteine and cysteamine. The thiols existing physiologically also inhibited reduced-carboxymethylated albumin, indicating that these thiols react preferentially with the enzyme itself rather than the substrate. The inhibitions of native albumin proteolysis were dose-dependent. These effects of thiols which have not been observed in other animal cathepsin D, suggest an essential function for cathepsin D in the human spleen.
Department of Applied Biological Science, Nihon University, College of Agriculture and Veterinary Medicine, Kanagawa, Japan.
K
K
Ikeda
T
T
Koseki
H
H
Suzuki
S
S
Nakagawa
D000418:Albumins / Q000378:metabolism*; D002402:Cathepsin D / Q000378:metabolism*; D003543:Cysteamine / Q000378:metabolism / Q000494:pharmacology; D003545:Cysteine / Q000378:metabolism / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005978:Glutathione / Q000378:metabolism / Q000494:pharmacology; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D013154:Spleen / Q000201:enzymology*; D013379:Substrate Specificity; D013438:Sulfhydryl Compounds / Q000494:pharmacology*
D000418:Albumins; D006454:Hemoglobins; D013438:Sulfhydryl Compounds; D003543:Cysteamine; D002402:Cathepsin D; D005978:Glutathione; D003545:Cysteine