title: ADAM10 is the major sheddase responsible for the release of membrane-associated meprin A.
abstract: Meprin A, composed of α and β subunits, is a membrane-bound metalloproteinase in renal proximal tubules. Meprin A plays an important role in tubular epithelial cell injury during acute kidney injury (AKI). The present study demonstrated that during ischemia-reperfusion-induced AKI, meprin A was shed from proximal tubule membranes, as evident from its redistribution toward the basolateral side, proteolytic processing in the membranes, and excretion in the urine. To identify the proteolytic enzyme responsible for shedding of meprin A, we generated stable HEK cell lines expressing meprin β alone and both meprin α and meprin β for the expression of meprin A. Phorbol 12-myristate 13-acetate and ionomycin stimulated ectodomain shedding of meprin β and meprin A. Among the inhibitors of various proteases, the broad spectrum inhibitor of the ADAM family of proteases, tumor necrosis factor-α protease inhibitor (TAPI-1), was most effective in preventing constitutive, phorbol 12-myristate 13-acetate-, and ionomycin-stimulated shedding of meprin β and meprin A in the medium of both transfectants. The use of differential inhibitors for ADAM10 and ADAM17 indicated that ADAM10 inhibition is sufficient to block shedding. In agreement with these results, small interfering RNA to ADAM10 but not to ADAM9 or ADAM17 inhibited meprin β and meprin A shedding. Furthermore, overexpression of ADAM10 resulted in enhanced shedding of meprin β from both transfectants. Our studies demonstrate that ADAM10 is the major ADAM metalloproteinase responsible for the constitutive and stimulated shedding of meprin β and meprin A. These studies further suggest that inhibiting ADAM 10 activity could be of therapeutic benefit in AKI.
authors.affiliation: From the Central Arkansas Veterans Healthcare System and.
authors.forename: Christian
authors.initials: C
authors.lastname: Herzog
authors.forename: Randy S
authors.initials: RS
authors.lastname: Haun
authors.forename: Andreas
authors.initials: A
authors.lastname: Ludwig
authors.forename: Sudhir V
authors.initials: SV
authors.lastname: Shah
authors.forename: Gur P
authors.initials: GP
authors.lastname: Kaushal
mesh_terms: D051722:ADAM Proteins / Q000235:genetics / Q000378:metabolism*; D000072197:ADAM10 Protein; D000072198:ADAM17 Protein; D058186:Acute Kidney Injury / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D053829:Amyloid Precursor Protein Secretases / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D061207:Calcium Ionophores / Q000494:pharmacology; D002273:Carcinogens / Q000494:pharmacology; D002462:Cell Membrane / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D057809:HEK293 Cells; D006801:Humans; D015759:Ionomycin / Q000494:pharmacology; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008666:Metalloendopeptidases / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D061207:Calcium Ionophores; D002273:Carcinogens; D008565:Membrane Proteins; D015759:Ionomycin; D053829:Amyloid Precursor Protein Secretases; D051722:ADAM Proteins; C098339:ADAM9 protein, human; C498316:Adam9 protein, mouse; D008666:Metalloendopeptidases; C053833:meprin A; D000072197:ADAM10 Protein; C491236:ADAM10 protein, human; C491234:Adam10 protein, mouse; D000072198:ADAM17 Protein; C000606462:ADAM17 protein, human; C000606463:Adam17 protein, mouse; D013755:Tetradecanoylphorbol Acetate
keywords: ADAM ADAMTS; ADAM10; ADAM17; Kidney; Meprin; Metalloprotease; Mouse; Shedding; siRNA