Azelnidipine is a calcium blocker that attenuates liver fibrosis and may increase antioxidant defence

BACKGROUND AND PURPOSE Oxidative stress plays a critical role in liver fibrogenesis. Reactive oxygen species (ROS) stimulate hepatic stellate cells (HSCs), and ROS-mediated increases in calcium influx further increase ROS production. Azelnidipine is a calcium blocker that has been shown to have antioxidant effects in endothelial cells and cardiomyocytes. Therefore, we evaluated the anti-fibrotic and antioxidative effects of azelnidipine on liver fibrosis. EXPERIMENTAL APPROACH We used TGF-beta 1-activated LX-2 cells (a human HSC line) and mouse models of fibrosis induced by treatment with either carbon tetrachloride (CCl4) or thioacetamide (TAA). KEY RESULTS Azelnidipine inhibited TGF-beta 1 and angiotensin II (Ang II)-activated alpha 1(I) collagen mRNA expression in HSCs. Furthermore, TGF-beta 1- and Ang II-induced oxidative stress and TGF-beta 1-induced p38 and JNK phosphorylation were reduced in HSCs treated with azelnidipine. Azelnidipine significantly decreased inflammatory cell infiltration, pro-fibrotic gene expressions, HSC activation, lipid peroxidation, oxidative DNA damage and fibrosis in the livers of CCl4- or TAA-treated mice. Finally, azelnidipine prevented a decrease in the expression of some antioxidant enzymes and accelerated regression of liver fibrosis in CCl4-treated mice. CONCLUSIONS AND IMPLICATIONS Azelnidipine inhibited TGF-beta 1- and Ang II-induced HSC activation in vitro and attenuated CCl4- and TAA-induced liver fibrosis, and it accelerated regression of CCl4-induced liver fibrosis in mice. The anti-fibrotic mechanism of azelnidipine against CCl4-induced liver fibrosis in mice may have been due an increased level of antioxidant defence. As azelnidipine is widely used in clinical practice without serious adverse effects, it may provide an effective new strategy for anti-fibrotic therapy.