Neutral endopeptidase-24.11 (NEP, EC 184.108.40.206) is a cell surface Zn metallopeptidase that hydrolyzes bioactive regulatory peptides. Using a spectrofluorimetric procedure, we assessed NEP activity in plasma membranes of normal human skin and lung fibroblasts. We found a considerable increase in NEP activity during fetal-to-adult transition. Adult skin fibroblasts from an old donor exhibited significantly higher levels of NEP activity than cells from young donors. Interestingly, however, the NEP activity of fibroblasts from a centenarian donor was similar to that of cells from young donors. Increased levels of NEP activity were also found in in vitro aged lung fibroblasts. Finally, adrenocorticotropin hormone (ACTH (1-24)), a regulatory peptide that can be cleaved by NEP, provoked an increase in enzymic activity in fetal and young adult donor fibroblasts and a decrease in this activity in fibroblasts from adult and old donors. This finding Suggests that ageing may affect NEP activity. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.
Neutral endopeptidase-24.11 (NEP) activity in human fibroblasts during development and ageing / D., Kletsas; E., Caselgrandi; D., Barbieri; D., Stathakos; C., Franceschi; Ottaviani, Enzo. - In: MECHANISMS OF AGEING AND DEVELOPMENT. - ISSN 0047-6374. - STAMPA. - 102:(1998), pp. 15-23.