Meanwhile, applying a 10% strain at 0.5 Hz for 24 h on LI90 cell lines that mimics mechanical stretch induced by increasing portal blood flow, causes increased MMP-1 and decreased MMP-2 and tissue inhibitor of metalloproteinases-1 (TIMP-1) and TIMP-2 production, suggesting that HSCs are activated by mechanical stretch at the early phase of portal hypertension and that the matrix stiffness has changed (Goto et al., 2004). Here, TIMP1 is linked to portal hypertension.