Figure 6. Glabridin suppresses bile acid uptake by depleting cell-surface NTCP.

(A) Glabridin inhibits taurocholate uptake. iNTCP cells were treated with glabridin (10, 25, and 50 μM) for three or 20 hours. After incubation with [³H]-taurocholate (TCA) for 15 minutes, cells were washed and intracellular radioactivity was quantified. Cyclosporin A (CsA, 10 μM) was used as a positive control in this assay. ^*P < 0.05, ^**P < 0.01, two-tailed unpaired t-test. (B) Glabridin counteracts bile acids to promote innate immune signaling. Primary human hepatocytes were sequentially treated with IFN-β (100 U/ml), TCA, and glabridin (50 μM), as shown in left panel. The expression of representative ISGs, including Mx1 and BST2, was quantified using qPCR. ns, not significant; ^**P < 0.01, two-tailed unpaired t-test.