Calpeptin

Biological Activity

Calpeptin is a potent, cell-permeable inhibitor of the Ca²⁺-dependent protease, calpain. Prevents collagen- and thrombin-induced platelet aggregation, probably by blocking calpain induced phospholipase C and thromboxane synthase activation. Potent cathepsin L inhibitor. Recently shown to preferentially inhibit a subset of protein-tyrosine phosphatases. Also inhibits SARS-CoV-2 M^pro in vitro (IC₅₀ = 10.7 μM) and inhibits viral replication.

Technical Data

The technical data provided above is for guidance only. For batch specific data refer to the Certificate of Analysis.
Tocris products are intended for laboratory research use only, unless stated otherwise.

Background References

1. Site-specific phosphorylation protects glycogen synthase kinase-3β from calpain-mediated truncation of its N and C termini.
   Ma S, Liu S, Huang Q, Xie B, Lai B, Wang C, Song B, Li M
   J. Biol. Chem., 2012;287(27):22521-32.
2. Cathepsins limit macrophage necroptosis through cleavage of Rip1 kinase.
   McComb S, Shutinoski B, Thurston S, Cessford E, Kumar K, Sad S
   J Immunol, 2014;192(12):5671-8.
3. Distinct regulatory functions of calpain 1 and 2 during neural stem cell self-renewal and differentiation.
   Santos DM, Xavier JM, Morgado AL, Sola S, Rodrigues CM
   PLoS ONE, 2012;7(3):e33468.
4. Platelet surface-associated activation and secretion-mediated inhibition of coagulation factor XII.
   Zakharova N, Artemenko E, Podoplelova N, Sveshnikova A, Demina I, Ataullakhanov F, Panteleev M
   PLoS ONE, 2015;10(2):e0116665.
5. High-throughput genotoxicity assay identifies antioxidants as inducers of DNA damage response and cell death.
   Fox JT, Sakamuru S, Huang R
   Proc. Natl. Acad. Sci. U.S.A., 2012;109(14):5423-8.
6. Cell-penetrating inhibitors of calpain.
   Mehdi
   TiBS, 1991;16:150
7. Inhibitory effect of di-and tripeptidyl aldehydes on calpains and cathepsins.
   Sasaki et al.
   J.Enzyme Inhib., 1990;3:195
8. Evidence for a calpeptin-sensitive protein-tyrosine phosphatase upstream of the small GTPase Rho.
   Schoenwaelder and Burridge
   J.Biol.Chem., 1999;274:14359
9. Synthesis of a new cell penetrating calpain inhibitor (calpeptin).
   Tsujinaka et al.
   Biochem.Biophys.Res.Commun., 1988;153:1201
10. Boceprevir, GC-376, and calpain inhibitors II, XII inhibit SARS-CoV-2 viral replication by targeting the viral main protease.
    Ma et al.
    Cell Res., 2020;

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