The elastin component of elastic fibres is degraded to soluble fragments by MMP2 (Murphy et al. 1991), MMP7 (Quantin et al. 1989, Murphy et al. 1991), MMP9 (Murphy et al. 1991, Katsuda et al. 1994) and MMP12 (macrophage elastase) (Shapiro et al. 1993, Taddese et al. 2008), and to a limited extent by MMP3 and 10 (Murphy et al. 1991). In addition, elastin is a substrate for neutrophil elastase (Reilly & Travis 1980).
Eighty-nine tropoelastin cleavage sites were identified for MMP-12, whereas MMP-7 and MMP-9 were found to cleave at only 58 and 63 sites, respectively (Heinz et al. 2010).