Inhibitory effects of caspase inhibitors on the activity of matrix metalloproteinase-2

• Published in: Biochemical pharmacology 2013-08, Vol.86 (4), p.469-475
• Main Authors: Castro, M.M., Fuah, J., Ali, M., Sung, M., Schulz, J., Kondo, M.Y., Fan, X., Holt, A., Schulz, R.
• Format: Article
• Language: English
• Subjects: Animals; Animals, Newborn; apoptosis; cardiomyocytes; Caspase 3 - metabolism; Caspase inhibitors; Caspase Inhibitors - pharmacology; caspase-3; Caspases; Cell Hypoxia; Cells, Cultured; fluorescence; gelatinase A; heart; Humans; Hydroxamic Acids - pharmacology; Hypoxia-reoxygenation; ischemia; Matrix Metalloproteinase 2 - metabolism; Matrix Metalloproteinase Inhibitors - pharmacology; Matrix metalloproteinase-2; Myocytes, Cardiac - drug effects; Myocytes, Cardiac - enzymology; Oligopeptides - pharmacology; pharmacology; Phenyl Ethers - pharmacology; protective effect; proteinase inhibitors; proteolysis; Rats; Rats, Sprague-Dawley; Sulfones - pharmacology; Troponin I; Troponin I - metabolism; Western blotting
• ISSN: 0006-2952; 1873-2968
• DOI: 10.1016/j.bcp.2013.06.003

In addition to their known inhibitory effects on caspases, some caspase inhibitors also block MMP activity. This may contribute to their attenuation of troponin I (TnI) proteolysis during ischemia-reperfusion (I/R) injury of the heart. Matrix metalloproteinase (MMP)-2, a zinc-dependent endopeptidase, plays a detrimental role in several diseases including ischemia and reperfusion (I/R) injury of the heart. Caspases are a group of cysteine-dependent, aspartate-directed proteases which regulate cellular apoptosis. Interestingly, protective effects of caspase inhibitors independent of apoptosis have been shown in I/R injury of the heart. The cardioprotective actions of both these classes of protease inhibitors led us to hypothesize that caspase inhibitors may also reduce MMP-2 activity. Five known caspase inhibitors (Z-IE(OMe)TD(OMe)-fmk, Ac-DEVD-CHO, Ac-LEHD-cmk, Z-VAD-fmk and Ac-YVAD-cmk) were tested for their possible inhibitory effects on MMP-2 activity in comparison to the MMP inhibitors ONO-4817 and ARP-100 (which themselves were unable to inhibit caspase-3 activity). MMP-2 activity was assessed by an in vitro troponin I (TnI) proteolysis assay and a quantitative kinetic fluorescence assay using a fluorogenic peptide substrate (OmniMMP). TnI proteolysis was also measured by western blot in neonatal cardiomyocytes subjected to hypoxia-reoxygenation injury. Using human recombinant MMP-2 and TnI as its substrate, the caspase inhibitors, in comparison with ONO-4817, significantly inhibited MMP-2-mediated TnI degradation in a concentration-dependent manner. The kinetic assay using OmniMMP revealed that these caspase inhibitors blocked MMP-2 activity in a concentration-dependent manner with similar IC50 values. TnI degradation in neonatal cardiomyocytes was enhanced following hypoxia-reoxygenation and this was blocked by ARP-100 and Ac-LEHD-cmk. Inhibition of MMP-2 activity is an additional pharmacological action which contributes to the protective effects of some caspase inhibitors.