Background: During liver injury, quiescent hepatic stellate cells (qHSCs) are activated by various cytokines and transdifferentiated into myofibroblast-like activated HSCs (aHSCs), which produce collagen, a major source of liver fibrosis. Therefore, the reversion of aHSC is regarded as a therapeutic target for liver fibrosis. Several epidemiological reports have revealed that intake of caffeine decreases the risk of liver fibrosis. In this study, therefore, we investigated the effect of caffeine on the reversion of aHSCs isolated from mice. We used aHSC activated by culturing in DMEM supplemented with 10% FBS for 7 days.
Results: Caffeine (0.1-10 mM) decreased the positive area of α-smooth muscle actin (α-SMA) in a concentration-dependent manner. Caffeine decreased the expression of COL1a1, an index of aHSC, and increased this of MMP-9, an index of qHSC. CGS-15943, an adenosine receptor inhibitor, had no significant effect on the area of α-SMA and the expression of COL1a1 and MMP-9.
Conclusion: Caffeine caused the reversion of aHSC in a concentration-dependent manner independently of adenosine receptor.