Inhibitory effect of a brain derived peptide preparation on the Ca++-dependent protease, calpain.

TitleInhibitory effect of a brain derived peptide preparation on the Ca++-dependent protease, calpain.
Publication TypeJournal Article
Year of Publication2000
AuthorsWronski, R., P. Tompa, B. Hutter-Paier, K. Crailsheim, P. Friedrich, and M. Windisch
JournalJ Neural Transm
Date Published2000
KeywordsAmino Acids, Animals, Binding Sites, Calcium, Calpain, Enzyme Activation, Nerve Degeneration, Neuroprotective Agents, Swine

Overactivated calpain might be a key factor in destruction of cytoskeletal proteins involved in the pathophysiology of ischemia and disorders like Alzheimer's disease. Therapeutic effects imply the possible interference of Cerebrolysin (Ebewe Arzneimittel, Austria) with these molecular events. In this work several in vitro methods have been applied to investigate the interaction between Cerebrolysin and calpain [Enzyme Commission (EC) number:]. A conventional caseinolytic assay beside two flourimetric assays using a synthetic peptide substrate and a fluorescence labelled cytoskeletal protein [microtubule-associated protein 2 labelled with 5-([4,6-dichlorotriazin-2-yl]amino) fluorescein (MAP2-DTAF)] respectively for a highly sensitive fluorimetric calpain activity assay were applied for kinetic analysis. The caseinolytic assay showed that the drug inhibits both mu- and m-calpain and to a significantly lower extent also trypsin [Enzyme Commission (EC) number:] and papain [Enzyme commission (EC) number:]. Dialysis experiments revealed Cerebrolysin mediated calpain inhibition to be reversible. Kinetic analysis exhibited a non-competitive, or tight-binding competitive, mode of inhibition. This latter mode, substantiated by serial dilution experiments, and the likely existence of calpastatin in a brain derivative suggests the occurrence of calpastatin fragments or calpastatin-like fragments in Cerebrolysin. The clearly competitive inhibition of trypsin by the drug indicates distinct mechanisms and active components against different proteases.

Alternate JournalJ Neural Transm
PubMed ID10847556