Table 1.

Hepatoprotective effects of silymarin-derived flavonolignans

	Antiviral (IC50)	Antiviral (IC50)	Antiviral (IC50)	Anti-Inflammatory (IC50)	Antioxidant (percent inhibition)	Immunomodulatory (percent inhibition)
Compound	HCV Protein*	HCV RNA†	RdRp*	NFkB*	ROS (%)	T-cell proliferation (%)
Silymarin	60	89.6	300	80	99.2	86.2
Silibinin	80	41	800	80	99.5	60.6
Silybin A	50	31.7	>800	40	68.7	71.4
Silybin B	80	24.5	600	40	74.0	47.5
Isosilybin A	40	14.6	>1,500	80	95.3	61.6
Isosilybin B‡	>40	53.9	>1,500	40	91.0	100
Silychristin	100	60	800	>80	78.9	30.3
Isosilychristin	>100	245	>1,500	>80	80.4	11
Silydianin	>100	>100	∼1,000	>80	52.1	2.8
Taxifolin	40	6.8	>1,500	40	96.3	0

IC50 data are expressed as concentrations in micromolars, both estimated* and actual^†. Antioxidant data reflect the percent inhibition of JFH-1-induced oxidative stress for flavonolignan treated infected cells versus DMSO solvent controls. For immunomodulatory function, data are expressed as percent-inhibition of CD3 induced proliferation at a compound concentration of 40 μM.

^‡Note that isosilybin B was toxic above 10 μM, so the concentrations for the reported activities are largely because of toxicity rather than a specific hepatoprotective function.