Specific Developmental Profiles of Lysosomal and Brush Border Enzymuria in the Human
| Autor: | Jean-Jacques Helwig, J. Geisert, Willard D, C. Hirt, G. Hamel, Thierry Massfelder, Messer J, B. Schnitzler, C. Koehl, Umberto Simeoni |
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| Rok vydání: | 1994 |
| Předmět: |
Male
β n acetylhexosaminidase Aging medicine.medical_specialty Adolescent Brush border Urinary system Physiology CD13 Antigens Biology Aminopeptidases Lysosome Internal medicine Acetylglucosaminidase Membrane alanyl aminopeptidase medicine Humans Child Microvilli Infant Newborn Infant gamma-Glutamyltransferase Enzymes medicine.anatomical_structure Endocrinology Child Preschool Creatinine Recien nacido Pediatrics Perinatology and Child Health Female Alanine aminopeptidase Proximal tubule Lysosomes beta 2-Microglobulin Infant Premature Developmental Biology |
| Zdroj: | Europe PubMed Central |
| ISSN: | 1661-7819 1661-7800 |
| Popis: | Various enzymatic urinary activities have been proposed to assess renal proximal tubule damage in children, including neonates. Nevertheless comprehensive knowledge on the developmental aspects of physiological enzymuria is limited, particularly with regard to lysosomal and brush border enzymuria. Urinary activities of two lysosomal enzymes, N-acetyl-β-D-glucosaminidase (NAG) and β-galactosidase (GAL), and of two brush border enzymes, alanine aminopeptidase (AAG) and γ-glutamyltransferase (GGT) were comparatively investigated in normal prematures (n = 28), term neonates (n = 52), infants aged less than 2 years (n = 19) and children (n = 33), and compared to urinary excretion of β2-microglobulin (B2M). Enzymatic activities were assayed using either spectrophotometrical (NAG, AAP, GGT) fluorimetrical (GAL) or radioimmunological (B2M) methods, and were related to urinary creatinine excretion. Developmental profiles of both the studied lysosomal enzymes and of B2M were similarly characterized with significantly decreasing values from prematures (NAG 9.29 ± 1.44, GAL 2.26 ± 0.26 IU/mmol creatinine, indicated as mean ± SEM) to term neonates (6,94 ± 0.58 and 1.76 ± 0.15 IU/ mmol creatinine, respectively) and older infants and children. Lysosomal enzymatic urinary activities correlated linearly with a coefficient of r = 0.75, (p < 0.05), while correlations between each lysosomal enzymatic activity and B2M urinary excretion were weaker. Profiles of both the studied brush border enzymes were characterized with lower activities in prematures (AAP 4.45 ± 0.44, GGT 5.52 ± 0.49 IU/mmol creatinine) than in term neonates (5.62 ± 0.92 and 9.1 ± 1.73 IU/mmol creatinine, respectively) or even in infants with respect to GGT (AAP 4.06 ± 0.72 and GGT 11.54 ± 1.71 IU/mmol creatinine), with a consecutive decrease of activities in older infants or children. It is concluded that lysosomal and brush border enzymuria follow different developmental profiles in the normal human. Studies involving enzymuria as a marker of tubular lesion should include the measurements of at least one lysosomal and one brush border enzymatic activity, and should be interpreted with reference to the respective, specific developmental profiles. |
| Databáze: | OpenAIRE |
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